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Wikipedia

Biofuel

Biofuel is a fuel that is produced over a short time span from biomass, rather than by the very slow natural processes involved in the formation of fossil fuels such as oil. Biofuel can be produced from plants or from agricultural, domestic or industrial biowaste.[1] Biofuels are mostly used for transportation, but can also be used for heating and electricity.[2]: 173 [3] Biofuels (and bioenergy in general) are regarded as a renewable energy source.[4]: 11  The use of biofuel has been subject to criticism regarding the "food vs fuel" debate, varied assessments of their sustainability, and possible deforestation and biodiversity loss as a result of biofuel production.

A sample of biodiesel

In general, biofuels emit fewer greenhouse gas emissions when burned in an engine and are generally considered carbon-neutral fuels as the carbon emitted has been captured from the atmosphere by the crops used in production.[5] However, life-cycle assessments of biofuels have shown large emissions associated with the potential land-use change required to produce additional biofuel feedstocks.[6][7] The outcomes of lifecycle assessments (LCAs) for biofuels are highly situational and dependent on many factors including the type of feedstock, production routes, data variations, and methodological choices. This could be added to emphasize the complexity and variability in assessing the environmental impacts of biofuels.[8] Estimates about the climate impact from biofuels vary widely based on the methodology and exact situation examined.[6] Therefore, the climate change mitigation potential of biofuel varies considerably: in some scenarios emission levels are comparable to fossil fuels, and in other scenarios the biofuel emissions result in negative emissions.

Global demand for biofuels is predicted to increase by 56% over 2022-2027.[9] By 2027 worldwide biofuel production is expected to supply 5.4% of the world's fuels for transport including 1% of aviation fuel.[10] Demand for aviation biofuel is forecast to increase.[11][12]

The two most common types of biofuel are bioethanol and biodiesel. Brazil is the largest producer of bioethanol, while the EU is the largest producer of biodiesel. The energy content in the global production of bioethanol and biodiesel is 2.2 and 1.8 EJ per year, respectively.[13]

Bioethanol is an alcohol made by fermentation, mostly from carbohydrates produced in sugar or starch crops such as maize, sugarcane, or sweet sorghum. Cellulosic biomass, derived from non-food sources, such as trees and grasses, is also being developed as a feedstock for ethanol production. Ethanol can be used as a fuel for vehicles in its pure form (E100), but it is usually used as a gasoline additive to increase octane ratings and improve vehicle emissions.

Biodiesel is produced from oils or fats using transesterification. It can be used as a fuel for vehicles in its pure form (B100), but it is usually used as a diesel additive to reduce levels of particulates, carbon monoxide, and hydrocarbons from diesel-powered vehicles.[14]

Terminology edit

 
Types and generation of biofuels

The term biofuel is used in different ways. One definition is "Biofuels are biobased products, in solid, liquid, or gaseous forms. They are produced from crops or natural products, such as wood, or agricultural residues, such as molasses and bagasse."[2]: 173 

Other publications reserve the term biofuel for liquid or gaseous fuels, used for transportation.[3]

The IPCC Sixth Assessment Report defines biofuel as "A fuel, generally in liquid form, produced from biomass. Biofuels include bioethanol from sugarcane, sugar beet or maize, and biodiesel from canola or soybeans.".[15]: 1795  It goes on to define biomass in this context as "organic material excluding the material that is fossilised or embedded in geological formations".[15]: 1795  This means that coal or other fossil fuels is not a form of biomass in this context.

Conventional biofuels (first generation) edit

First-generation biofuels (also denoted as "conventional biofuels") are made from food crops grown on arable land.[16][17]: 447  The crop's sugar, starch, or oil content is converted into biodiesel or ethanol, using transesterification, or yeast fermentation.[18]

Advanced biofuels edit

To avoid a "food versus fuel" dilemma, second-generation biofuels and third-generation biofuels (also called advanced biofuels or sustainable biofuels or drop-in biofuels) are made from feedstocks which do not directly compete with food or feed crop such as waste products and energy crops.[19] A wide range of waste feedstocks such as those derived from agriculture and forestry activities like rice straw, rice husk, wood chips, and sawdust can be used to produce advanced biofuels through biochemical and thermochemical processes.[17]: 448 

The feedstock used to make the fuels either grow on arable land but are byproducts of the main crop, or they are grown on marginal land. Second-generation feedstocks also include straw, bagasse, perennial grasses, jatropha, waste vegetable oil, municipal solid waste and so forth.[20]

Types edit

Liquid edit

Ethanol edit

Biologically produced alcohols, most commonly ethanol, and less commonly propanol and butanol, are produced by the action of microorganisms and enzymes through the fermentation of sugars or starches (easiest to produce) or cellulose (more difficult to produce).The IEA estimates that ethanol production used 20% of sugar supplies and 13% of corn supplies in 2021.[21]

Ethanol fuel is the most common biofuel worldwide, particularly in Brazil. Alcohol fuels are produced by fermentation of sugars derived from wheat, corn, sugar beets, sugar cane, molasses and any sugar or starch from which alcoholic beverages such as whiskey, can be made (such as potato and fruit waste, etc.). Production methods used are enzyme digestion (to release sugars from stored starches), fermentation of the sugars, distillation and drying. The distillation process requires significant energy input to generate heat. Heat is sometimes generated with unsustainable natural gas fossil fuel, but cellulosic biomass such as bagasse is the most common fuel in Brazil, while pellets, wood chips and also waste heat are more common in Europe. Corn-to-ethanol and other food stocks has led to the development of cellulosic ethanol.[22]

Other bioalcohols edit

Methanol is currently produced from natural gas, a non-renewable fossil fuel. In the future it is hoped to be produced from biomass as biomethanol. This is technically feasible, but the production is currently being postponed for concerns that the economic viability is still pending.[23] The methanol economy is an alternative to the hydrogen economy to be contrasted with today's hydrogen production from natural gas.

Butanol (C
4
H
9
OH
) is formed by ABE fermentation (acetone, butanol, ethanol) and experimental modifications of the process show potentially high net energy gains with biobutanol as the only liquid product. Biobutanol is often claimed to provide a direct replacement for gasoline, because it will produce more energy than ethanol and allegedly can be burned "straight" in existing gasoline engines (without modification to the engine or car),[24] is less corrosive and less water-soluble than ethanol, and could be distributed via existing infrastructures. Escherichia coli strains have also been successfully engineered to produce butanol by modifying their amino acid metabolism.[25] One drawback to butanol production in E. coli remains the high cost of nutrient rich media, however, recent work has demonstrated E. coli can produce butanol with minimal nutritional supplementation.[26] Biobutanol is sometimes called biogasoline, which is incorrect as it is chemically different, being an alcohol and not a hydrocarbon like gasoline.

Biodiesel edit

 
Biofuel pumps, 2010

Biodiesel is the most common biofuel in Europe. It is produced from oils or fats using transesterification and is a liquid similar in composition to fossil/mineral diesel. Chemically, it consists mostly of fatty acid methyl (or ethyl) esters (FAMEs).[27] Feedstocks for biodiesel include animal fats, vegetable oils, soy, rapeseed, jatropha, mahua, mustard, flax, sunflower, palm oil, hemp, field pennycress, Pongamia pinnata and algae. Pure biodiesel (B100, also known as "neat" biodiesel) currently reduces emissions with up to 60% compared to diesel Second generation B100.[28] As of 2020, researchers at Australia's CSIRO have been studying safflower oil as an engine lubricant, and researchers at Montana State University's Advanced Fuels Center in the US have been studying the oil's performance in a large diesel engine, with results described as a "breakthrough".[29]

 
Targray Biofuels Division railcar transporting Biodiesel.

Biodiesel can be used in any diesel engine and modified equipment when mixed with mineral diesel. It can also be used in its pure form (B100) in diesel engines, but some maintenance and performance problems may occur during wintertime utilization, since the fuel becomes somewhat more viscous at lower temperatures, depending on the feedstock used.[30]

Electronically controlled 'common rail' and 'Unit Injector' type systems from the late 1990s onwards can only use biodiesel blended with conventional diesel fuel. These engines have finely metered and atomized multiple-stage injection systems that are very sensitive to the viscosity of the fuel. Many current-generation diesel engines are designed to run on B100 without altering the engine itself, although this depends on the fuel rail design. Since biodiesel is an effective solvent and cleans residues deposited by mineral diesel, engine filters may need to be replaced more often, as the biofuel dissolves old deposits in the fuel tank and pipes. It also effectively cleans the engine combustion chamber of carbon deposits, helping to maintain efficiency.

Biodiesel is an oxygenated fuel, meaning it contains a reduced amount of carbon and higher hydrogen and oxygen content than fossil diesel. This improves the combustion of biodiesel and reduces the particulate emissions from unburnt carbon. However, using pure biodiesel may increase NOx-emissions[31] Biodiesel is also safe to handle and transport because it is non-toxic and biodegradable, and has a high flash point of about 300 °F (148 °C) compared to petroleum diesel fuel, which has a flash point of 125 °F (52 °C).[32]

In many European countries, a 5% biodiesel blend is widely used and is available at thousands of gas stations.[33][34] In France, biodiesel is incorporated at a rate of 8% in the fuel used by all French diesel vehicles.[35] Avril Group produces under the brand Diester, a fifth of 11 million tons of biodiesel consumed annually by the European Union.[36] It is the leading European producer of biodiesel.[35]

Green diesel edit

Green diesel can be produced combination of biochemical and thermochemical processes. Conventional green diesel is produced through hydroprocessing biological oil feedstocks, such as vegetable oils and animal fats.[37][38] Recently, it is produced using series of thermochemical processes such as pyrolysis and hydroprocessing. In the thermochemical route, syngas produced from gasification, bio-oil produced from pyrolysis or biocrude produced from hydrothermal liquefaction is upgraded to green diesel using hydroprocessing.[39][40][41] Hydroprocessing is the process of using hydrogen to reform a molecular structure. For example, hydrocracking which is a widely used hydroprocessing technique in refineries is used at elevated temperatures and pressure in the presence of a catalyst to break down larger molecules, such as those found in vegetable oils, into shorter hydrocarbon chains used in diesel engines.[42] Green diesel may also be called renewable diesel, drop-in biodiesel, hydrotreated vegetable oil (HVO fuel)[42] or hydrogen-derived renewable diesel.[38] Unlike biodiesel, green diesel has exactly the same chemical properties as petroleum-based diesel.[42][43] It does not require new engines, pipelines or infrastructure to distribute and use, but has not been produced at a cost that is competitive with petroleum.[38] Gasoline versions are also being developed.[44] Green diesel is being developed in Louisiana and Singapore by ConocoPhillips, Neste Oil, Valero, Dynamic Fuels, and Honeywell UOP[38][45] as well as Preem in Gothenburg, Sweden, creating what is known as Evolution Diesel.[46]

Straight vegetable oil edit

 
A biofuel truck in 2009[47]

Straight unmodified edible vegetable oil is generally not used as fuel, but lower-quality oil has been used for this purpose. Used vegetable oil is increasingly being processed into biodiesel, or (more rarely) cleaned of water and particulates and then used as a fuel. The IEA estimates that biodiesel production used 17% of global vegetable oil supplies in 2021.[21]

Oils and fats reacted with 10 pounds of a short-chain alcohol (usually methanol) in the presence of a catalyst (usually sodium hydroxide [NaOH] can be hydrogenated to give a diesel substitute.[48] The resulting product is a straight-chain hydrocarbon with a high cetane number, low in aromatics and sulfur and does not contain oxygen. Hydrogenated oils can be blended with diesel in all proportions. They have several advantages over biodiesel, including good performance at low temperatures, no storage stability problems and no susceptibility to microbial attack.[49]

Biogasoline edit

Biogasoline can be produced biologically and themochemically. Using biologicalical methods, a study led by Professor Lee Sang-yup at the Korea Advanced Institute of Science and Technology (KAIST) and published in the international science journal Nature used modified E. coli fed with glucose found in plants or other non-food crops to produce biogasoline with the produced enzymes. The enzymes converted the sugar into fatty acids and then turned these into hydrocarbons that were chemically and structurally identical to those found in commercial gasoline fuel.[50] The thermochemical approach of producing biogasoline are similar to those used to produced biodiesel.[39][40][41] Biogasoline may also be called drop-in gasoline or renewable gasoline.

Bioethers edit

 
Neat ethanol on the left (A), gasoline on the right (G) at a filling station in Brazil in 2008

Bioethers (also referred to as fuel ethers or oxygenated fuels) are cost-effective compounds that act as octane rating enhancers. "Bioethers are produced by the reaction of reactive iso-olefins, such as iso-butylene, with bioethanol."[51][attribution needed] Bioethers are created from wheat or sugar beets, and also be produced from the waste glycerol that results from the production of biodiesel.[52] They also enhance engine performance, while significantly reducing engine wear and toxic exhaust emissions. By greatly reducing the amount of ground-level ozone emissions, they contribute to improved air quality.[53][54]

In transportation fuel there are six ether additives: dimethyl ether (DME), diethyl ether (DEE), methyl tert-butyl ether (MTBE), ethyl tert-butyl ether (ETBE), tert-amyl methyl ether (TAME), and tert-amyl ethyl ether (TAEE).[55]

The European Fuel Oxygenates Association identifies MTBE and ETBE as the most commonly used ethers in fuel to replace lead. Ethers were introduced in Europe in the 1970s to replace the highly toxic compound.[56] Although Europeans still use bioether additives, the U.S. Energy Policy Act of 2005 lifted a requirement for reformulated gasoline to include an oxygenate, leading to less MTBE being added to fuel.[57] Although bioethers are likely to replace ethers produced from petroleum in the UK, it is highly unlikely they will become a fuel in and of itself due to the low energy density.[58]

Aviation biofuel edit

 
Refueling an Airbus A320 with biofuel in 2011

An aviation biofuel (also known as bio-jet fuel[59] or bio-aviation fuel (BAF);[60]) is a biofuel used to power aircraft and is a sustainable aviation fuel (SAF). The International Air Transport Association (IATA) considers it a key element in reducing the environmental impact of aviation.[61] Aviation biofuel is used to decarbonize medium and long-haul air travel. These types of travel generate the most emissions, and could extend the life of older aircraft types by lowering their carbon footprint. Synthetic paraffinic kerosene (SPK) refers to any non-petroleum-based fuel designed to replace kerosene jet fuel, which is often, but not always, made from biomass.

Biofuels are biomass-derived fuels from plants, animals, or waste; depending on which type of biomass is used, they could lower CO2 emissions by 20–98% compared to conventional jet fuel.[62] The first test flight using blended biofuel was in 2008,and in 2011, blended fuels with 50% biofuels were allowed on commercial flights. In 2023 SAF production was 600 million liters, representing 0.2% of global jet fuel use.[63]

Aviation biofuel can be produced from plant or animal sources such as Jatropha, algae, tallows, waste oils, palm oil, Babassu, and Camelina (bio-SPK); from solid biomass using pyrolysis processed with a Fischer–Tropsch process (FT-SPK); with an alcohol-to-jet (ATJ) process from waste fermentation; or from synthetic biology through a solar reactor. Small piston engines can be modified to burn ethanol.

Sustainable biofuels are an alternative to electrofuels.[64] Sustainable aviation fuel is certified as being sustainable by a third-party organisation.

Gaseous edit

Biogas and biomethane edit

 
Biogas plant in 2007

Biogas is a mixture composed primarily of methane and carbon dioxide produced by the process of anaerobic digestion of organic material by micro-organisms. Other trace components of this mixture includes water vapor, hydrogen sulfide, siloxanes, hydrocarbons, ammonia, oxygen, carbon monoxide, and nitrogen.[65][66] It can be produced either from biodegradable waste materials or by the use of energy crops fed into anaerobic digesters to supplement gas yields. The solid byproduct, digestate, can be used as a biofuel or a fertilizer. When CO2 and other impurities are removed from biogas, it is called biomethane. The CO2 can also be combined with hydrogen in methanation to form more methane.

Biogas can be recovered from mechanical biological treatment waste processing systems. Landfill gas, a less clean form of biogas, is produced in landfills through naturally occurring anaerobic digestion. If it escapes into the atmosphere, it acts as a greenhouse gas.

In Sweden "waste-to-energy" power plants capture methane biogas from garbage and use it power transport systems.[67] Farmers can produce biogas from cattle manure via anaerobic digesters.[68]

Syngas edit

Syngas, a mixture of carbon monoxide, hydrogen and various hydrocarbons, is produced by partial combustion of biomass (combustion with an amount of oxygen that is not sufficient to convert the biomass completely to carbon dioxide and water).[49] Before partial combustion the biomass is dried and sometimes pyrolysed. Syngas is more efficient than direct combustion of the original biofuel; more of the energy contained in the fuel is extracted.

Syngas may be burned directly in internal combustion engines, turbines or high-temperature fuel cells.[69] The wood gas generator, a wood-fueled gasification reactor, can be connected to an internal combustion engine.

Syngas can be used to produce methanol, dimethyl ether and hydrogen, or converted via the Fischer–Tropsch process to produce a diesel substitute, or a mixture of alcohols that can be blended into gasoline. Gasification normally relies on temperatures greater than 700 °C.

Lower-temperature gasification is desirable when co-producing biochar, but results in syngas polluted with tar.

Solid edit

The term "biofuels" is also used for solid fuels that are made from biomass, even though this is less common.[3]

Research into other types edit

Algae-based biofuels edit

Algae can be produced in ponds or tanks on land, and out at sea.[70][71] Algal fuels have high yields,[72] a high ignition point,[73] can be grown with minimal impact on fresh water resources,[74][75][76] can be produced using saline water and wastewater, and are biodegradable and relatively harmless to the environment if spilled.[77][78] However, production requires large amounts of energy and fertilizer, the produced fuel degrades faster than other biofuels, and it does not flow well in cold temperatures.[70][79]

By 2017, due to economic considerations, most efforts to produce fuel from algae have been abandoned or changed to other applications.[80]

Third and fourth-generation biofuels also include biofuels that are produced by bioengineered organisms i.e. algae and cyanobacteria.[81] Algae and cyanobacteria will use water, carbon dioxide, and solar energy to produce biofuels.[81] This method of biofuel production is still at the research level. The biofuels that are secreted by the bioengineered organisms are expected to have higher photon-to-fuel conversion efficiency, compared to older generations of biofuels.[81] One of the advantages of this class of biofuels is that the cultivation of the organisms that produce the biofuels does not require the use of arable land.[82] The disadvantages include the cost of cultivating the biofuel-producing organisms being very high.[82]

Electrofuels and solar fuels edit

Electrofuels[citation needed] and solar fuels may or may not be biofuels, depending on whether they contain biological elements. Electrofuels are made by storing electrical energy in the chemical bonds of liquids and gases. The primary targets are butanol, biodiesel, and hydrogen, but include other alcohols and carbon-containing gases such as methane and butane. A solar fuel is a synthetic chemical fuel produced from solar energy. Light is converted to chemical energy, typically by reducing protons to hydrogen, or carbon dioxide to organic compounds.[83]

Bio-digesters edit

A bio-digester is a mechanized toilet that uses decomposition and sedimentation to turn human waste into a renewable fuel called biogas. Biogas can be made from substances like agricultural waste and sewage.[84][85] The bio-digester uses a process called anaerobic digestion to produce biogas. Anaerobic digestion uses a chemical process to break down organic matter with the use of microorganisms in the absence of oxygen to produce biogas.[86] The processes involved in anaerobic respiration are hydrolysis, acidogenesis, acetogenesis, and methanogenesis.[87]

Extent of production and use edit

 
Biofuel energy production, 2022[88]
 
Biofuel production by region

Global biofuel production was 81 Mtoe in 2017 which represented an annual increase of about 3% compared to 2010.[4]: 12  In 2017 the US was the largest biofuel producer in the world producing 37 Mtoe, followed by Brazil and South America at 23 Mtoe and Europe (mainly Germany) at 12 Mtoe.[4]: 12 

An assessment from 2017 found that: "Biofuels will never be a major transport fuel as there is just not enough land in the world to grow plants to make biofuel for all vehicles. It can however, be part of an energy mix to take us into a future of renewable energy."[4]: 11 

In 2021 worldwide biofuel production provided 4.3% of the world's fuels for transport, including a very small amount of aviation biofuel.[10] By 2027 worldwide biofuel production is expected to supply 5.4% of the world's fuels for transport including 1% of aviation fuel.[10]

The US, Europe, Brazil and Indonesia are driving the majority of biofuel consumption growth. This demand for biodiesel, renewable diesel and biojet fuel is projected to increase by 44% (21 billion litres) over 2022-2027.[89]

Issues edit

 
Wheat fields in the USA: wheat is grown for food but also for biofuel production.

Issues relating to biofuel are social, economic, environmental and technical problems that may arise from biofuel production and use. Social and economic issues include the "food vs fuel" debate and the need to develop responsible policies and economic instruments to ensure sustainable biofuel production. Farming for biofuels feedstock can be detrimental to the environment if not done sustainably. Environmental concerns include deforestation, biodiversity loss and soil erosion as a result of land clearing for biofuels agriculture. While biofuels can contribute to reduction in global carbon emissions, indirect land use change for biofuel production can have the inverse effect. Technical issues include possible modifications necessary to run the engine on biofuel, as well as energy balance and efficiency.

The International Resource Panel outlined the wider and interrelated factors that need to be considered when deciding on the relative merits of pursuing one biofuel over another.[90] The IRP concluded that not all biofuels perform equally in terms of their effect on climate, energy security and ecosystems, and suggested that environmental and social effects need to be assessed throughout the entire life-cycle.

Environmental impacts edit

 
Deforestation in Indonesia, to make way for an oil palm plantation.[91]

Estimates about the climate impact from biofuels vary widely based on the methodology and exact situation examined.[6]

In general, biofuels emit fewer greenhouse gas emissions when burned in an engine and are generally considered carbon-neutral fuels as the carbon they emit has been captured from the atmosphere by the crops used in biofuel production.[5] They can have greenhouse gas emissions ranging from as low as -127.1 gCO2eq per MJ when carbon capture is incorporated into their production to those exceeding 95 gCO2eq per MJ when land-use change is significant. [40][41] Several factors are responsible for the variation in emission numbers of biofuel such as feedstock and its origin, fuel production technique, system boundary definitions, and energy sources.[41] However, many government policies such as those by European Union and the UK require that biofuels have at least 65% greenhouse gas emissions savings (or 70% if it is renewable fuels of non-biological origins) relative to fossil fuels.[92][93]

Life-cycle assessments of first generation biofuels have shown large emissions associated with the potential land-use change required to produce additional biofuel feedstocks.[6][7] If no land-use change is involved, first-generation biofuels can—on average—have lower emissions than fossil fuels.[6] However, biofuel production can compete with foodcrop production. Up to 40% of corn produced in the United States is used to make ethanol[94] and worldwide 10% of all grain is turned into biofuel.[95] A 50% reduction in grain used for biofuels in the US and Europe would replace all of Ukraine's grain exports.[96] Several studies have shown that reductions in emissions from biofuels are achieved at the expense of other impacts, such as acidification, eutrophication, water footprint and biodiversity loss.[6]

The use of second generation biofuels is thought to increase environmental sustainability, since the non-food part of plants is being used to produce second-generation biofuels, instead of being disposed.[97] But the use of second-generation biofuels increases the competition for lignocellulosic biomass, increasing the cost of these biofuels.[98]

Third generation biofuels, produced from Algae, in theory shouldn't have as negative an impact on the environment than first or second generation biofuels, due to lower changes in land use and not requiring pesticide use for production.[99] When looking at the data however, it has been shown that the environmental cost to produce the infrastructure and energy required for third generation biofuel production, is higher than the benefits provided from the biofuels use.[100]

The European Commission has officially approved a measure to phase out palm oil-based biofuels by 2030.[101][102] Unsustainable palm oil agriculture has caused significant environmental and social problems, including deforestation and pollution.

The production of biofuels can be very energy intensive, which if generated from non-renewable sources can heavily mitigate the benefits gained through biofuel use. A solution proposed to solve this issue is to supply biofuel production facilities with excess nuclear energy, which can supplement the energy provided by fossil fuels.[103] This can provide a carbon inexpensive solution, to help reduce the environmental impacts of biofuel production.

Indirect land use change impacts of biofuels edit

 
Brazilian cerrado
 
Amazon rainforest

The indirect land use change impacts of biofuels, also known as ILUC or iLUC (pronounced as i-luck), relates to the unintended consequence of releasing more carbon emissions due to land-use changes around the world induced by the expansion of croplands for ethanol or biodiesel production in response to the increased global demand for biofuels.[104][105]

As farmers worldwide respond to higher crop prices in order to maintain the global food supply-and-demand balance, pristine lands are cleared to replace the food crops that were diverted elsewhere to biofuels' production. Because natural lands, such as rainforests and grasslands, store carbon in their soil and biomass as plants grow each year, clearance of wilderness for new farms translates to a net increase in greenhouse gas emissions. Due to this off-site change in the carbon stock of the soil and the biomass, indirect land use change has consequences in the greenhouse gas (GHG) balance of a biofuel.[104][105][106][107]

Other authors have also argued that indirect land use changes produce other significant social and environmental impacts, affecting biodiversity, water quality, food prices and supply, land tenure, worker migration, and community and cultural stability.[106][108][109][110]

See also edit

References edit

  1. ^ "Biofuel | Definition, Types, & Pros and Cons | Britannica". www.britannica.com. 18 March 2024. Retrieved 2 April 2024.
  2. ^ a b T. M. Letcher, ed. (2020). "Chapter 9: Biofuels for transport". Future energy : improved, sustainable and clean options for our planet (3rd ed.). Amsterdam, Netherlands. ISBN 978-0-08-102887-2. OCLC 1137604985.{{cite book}}: CS1 maint: location missing publisher (link)
  3. ^ a b c "Biofuels explained - U.S. Energy Information Administration (EIA)". www.eia.gov. Retrieved 24 January 2023.
  4. ^ a b c d T. M. Letcher, ed. (2020). "Chapter1: Introduction With a Focus on Atmospheric Carbon Dioxide and Climate Change". Future energy : improved, sustainable and clean options for our planet (3rd ed.). Amsterdam, Netherlands. ISBN 978-0-08-102887-2. OCLC 1137604985.{{cite book}}: CS1 maint: location missing publisher (link)
  5. ^ a b Lewandrowski J, Rosenfeld J, Pape D, Hendrickson T, Jaglo K, Moffroid K (25 March 2019). "The greenhouse gas benefits of corn ethanol – assessing recent evidence". Biofuels. 11 (3). Informa UK Limited: 361–375. doi:10.1080/17597269.2018.1546488. ISSN 1759-7269. S2CID 134824935.
  6. ^ a b c d e f Jeswani HK, Chilvers A, Azapagic A (November 2020). "Environmental sustainability of biofuels: a review". Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences. 476 (2243): 20200351. Bibcode:2020RSPSA.47600351J. doi:10.1098/rspa.2020.0351. PMC 7735313. PMID 33363439.
  7. ^ a b Lark TJ, Hendricks NP, Smith A, Pates N, Spawn-Lee SA, Bougie M, et al. (March 2022). "Environmental outcomes of the US Renewable Fuel Standard". Proceedings of the National Academy of Sciences of the United States of America. 119 (9). Bibcode:2022PNAS..11901084L. doi:10.1073/pnas.2101084119. PMC 8892349. PMID 35165202.
  8. ^ Jeswani HK, Chilvers A, Azapagic A (November 2020). "Environmental sustainability of biofuels: a review". Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences. 476 (2243). Bibcode:2020RSPSA.47600351J. doi:10.1098/rspa.2020.0351. ISSN 1364-5021. PMC 7735313. PMID 33363439.
  9. ^ "Biofuel is approaching a feedstock crunch. How bad? And what must be done?". Energy Post. 23 January 2023. Retrieved 14 March 2024.
  10. ^ a b c "Transport biofuels – Renewables 2022 – Analysis". IEA. Retrieved 30 January 2023.
  11. ^ "Biofuel is approaching a feedstock crunch. How bad? And what must be done?". Energy Post. 23 January 2023. Retrieved 30 January 2023.
  12. ^ "How to scale Sustainable Aviation Fuel in the next decade". World Economic Forum. Retrieved 30 January 2023.
  13. ^ "Renewables Report 2022". IEA.
  14. ^ Bayetero CM, Yépez CM, Cevallos IB, Rueda EH (January 2022). "Effect of the use of additives in biodiesel blends on the performance and opacity of a diesel engine". Materials Today: Proceedings. Advances in Mechanical Engineering Trends. 49: 93–99. doi:10.1016/j.matpr.2021.07.478. ISSN 2214-7853. S2CID 238787289.
  15. ^ a b IPCC, 2022: Annex I: Glossary [van Diemen, R., J.B.R. Matthews, V. Möller, J.S. Fuglestvedt, V. Masson-Delmotte, C.  Méndez, A. Reisinger, S. Semenov (eds)]. In IPCC, 2022: Climate Change 2022: Mitigation of Climate Change. Contribution of Working Group III to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change [P.R. Shukla, J. Skea, R. Slade, A. Al Khourdajie, R. van Diemen, D. McCollum, M. Pathak, S. Some, P. Vyas, R. Fradera, M. Belkacemi, A. Hasija, G. Lisboa, S. Luz, J. Malley, (eds.)]. Cambridge University Press, Cambridge, UK and New York, NY, USA. doi: 10.1017/9781009157926.020
  16. ^ Cavelius P, Engelhart-Straub S, Mehlmer N, Lercher J, Awad D, Brück T (30 March 2023). "The potential of biofuels from first to fourth generation". PLOS Biology. 21 (3): e3002063. doi:10.1371/journal.pbio.3002063. ISSN 1545-7885. PMC 10063169. PMID 36996247.
  17. ^ a b T. M. Letcher, ed. (2020). "Chapter 21: Energy from biomass". Future energy : improved, sustainable and clean options for our planet (3rd ed.). Amsterdam, Netherlands. ISBN 978-0-08-102887-2. OCLC 1137604985.{{cite book}}: CS1 maint: location missing publisher (link)
  18. ^ . 21 May 2010. Archived from the original on 21 May 2010.
  19. ^ European Parliament. "Advanced biofuels" (PDF). Retrieved 19 April 2024.
  20. ^ "Biofuels – Second Generation Biofuels". biofuel.org.uk. from the original on 15 July 2019. Retrieved 18 January 2018.
  21. ^ a b "Is the biofuel industry approaching a feedstock crunch? – Analysis". IEA. Retrieved 2 January 2023.
  22. ^ Houghton J, Weatherwax S, Ferrell J (7 June 2006). Breaking the biological barriers to cellulosic ethanol: a joint research agenda (Report). Washington, DC (United States): EERE Publication and Product Library. doi:10.2172/1218382.
  23. ^ Börjesson P, Lundgren J, Ahlgren S, Nyström I (18 June 2013). Dagens och framtidens hållbara biodrivmedel: underlagsrapport från f3 till utredningen om fossilfri fordonstrafik [Today's and the future's sustainable biofuels: background report from f3 to the inquiry into fossil-free vehicle traffic.] (Report) (in Swedish). Vol. 13. The Swedish Knowledge Centre for Renewable Transportation Fuels. p. 170.
  24. ^ "ButylFuel, LLC Main Page". Butanol.com. 15 August 2005. from the original on 10 July 2019. Retrieved 14 July 2010.
  25. ^ Evans J (14 January 2008). "Biofuels aim higher". Biofuels, Bioproducts and Biorefining (BioFPR). from the original on 10 August 2009. Retrieved 3 December 2008.
  26. ^ Pontrelli S, Fricke RC, Sakurai SS, Putri SP, Fitz-Gibbon S, Chung M, et al. (September 2018). "Directed strain evolution restructures metabolism for 1-butanol production in minimal media". Metabolic Engineering. 49: 153–163. doi:10.1016/j.ymben.2018.08.004. PMID 30107263.
  27. ^ Fukuda H, Kondo A, Noda H (January 2001). "Biodiesel fuel production by transesterification of oils". Journal of Bioscience and Bioengineering. 92 (5): 405–416. doi:10.1016/s1389-1723(01)80288-7. PMID 16233120.
  28. ^ . Archived from the original on 4 August 2014. Retrieved 21 June 2014.
  29. ^ Lee T (7 June 2020). "Safflower oil hailed by scientists as possible recyclable, biodegradable replacement for petroleum". ABC News. Landline. Australian Broadcasting Corporation. from the original on 7 June 2020. Retrieved 7 June 2020.
  30. ^ "Alternative Fuels Data Center: Biodiesel Blends". afdc.energy.gov. Retrieved 31 March 2022.
  31. ^ Nylund NO, Koponen K (2012). (PDF) (Report). VTT Technical Research Centre of Finland. Archived from the original (PDF) on 16 February 2020.. Possibly the new emission standards Euro VI/EPA 10 will lead to reduced NOx-levels also when using B100.
  32. ^ . Hempcar.org. Archived from the original on 20 May 2011. Retrieved 14 July 2010.
  33. ^ "ADM Biodiesel: Hamburg, Leer, Mainz". Biodiesel.de. from the original on 2 August 2009. Retrieved 14 July 2010.
  34. ^ RRI Limited for Biodiesel Filling Stations. . Biodieselfillingstations.co.uk. Archived from the original on 14 July 2018. Retrieved 14 July 2010.
  35. ^ a b Avril Group : Activity Report 2014, p. 58
  36. ^ EurObserv 2014, p. 4
  37. ^ Brown R, Holmgren J. "Fast Pyrolysis and Bio-Oil Upgrading" (PDF). (PDF) from the original on 5 January 2012. Retrieved 15 March 2012.
  38. ^ a b c d "Alternative & Advanced Fuels". US Department of Energy. from the original on 27 October 2012. Retrieved 7 March 2012.
  39. ^ a b "Technology | Comsyn". www.comsynproject.eu. Retrieved 19 April 2024.
  40. ^ a b c Lilonfe S, Dimitriou I, Davies B, Abdul-Manan AF, McKechnie J (1 January 2024). "Comparative techno-economic and life cycle analyses of synthetic "drop-in" fuel production from UK wet biomass". Chemical Engineering Journal. 479: 147516. doi:10.1016/j.cej.2023.147516. ISSN 1385-8947.
  41. ^ a b c d Lilonfe S, Davies B, Abdul-Manan AF, Dimitriou I, McKechnie J (17 April 2024). "A review of techno-economic analyses and life cycle greenhouse gas emissions of biomass-to-hydrocarbon "drop-in" fuels". Sustainable Production and Consumption. doi:10.1016/j.spc.2024.04.016. ISSN 2352-5509.
  42. ^ a b c Knothe G (June 2010). "Biodiesel and renewable diesel: a comparison". Progress in Energy and Combustion Science. 36 (3): 364–373. doi:10.1016/j.pecs.2009.11.004. from the original on 6 November 2012. Retrieved 23 August 2012.
  43. ^ "Green Diesel v. Biodiesel". from the original on 5 August 2018. Retrieved 5 August 2018.
  44. ^ Jessica E. "Breakthroughs in Green Gasoline Production". Biomass Magazine. from the original on 11 March 2012. Retrieved 14 August 2012.
  45. ^ Albrecht KO, Hallen RT (March 2011). A Brief Literature Overview of Various Routes to Biorenewable Fuels from Lipids for the National Alliance of Advanced Biofuels and Bio-products NAAB Consortium (PDF) (Report). Prepared by the US Department of Energy. (PDF) from the original on 12 July 2012. Retrieved 23 August 2012.
  46. ^ . August 2014. Archived from the original on 1 August 2014.
  47. ^ "Wal-Mart To Test Hybrid Trucks". Sustainable Business. 3 February 2009. from the original on 8 May 2014. Retrieved 8 May 2014.
  48. ^ "Alternative Fuels Data Center: Biodiesel Production and Distribution". afdc.energy.gov. Retrieved 31 March 2022.
  49. ^ a b Evans G (14 April 2008). (Report). National Non-Food Crops Centre. Archived from the original on 11 June 2008.
  50. ^ (Report). Fuels&Lubes Daily. 4 November 2013. Archived from the original on 7 September 2022.
  51. ^ Rock K, Korpelshoek M (2007). "Bioethers Impact on the Gasoline Pool". Digital Refining. from the original on 14 November 2016. Retrieved 15 February 2014.
  52. ^ "Biofuels - Types of Biofuels - Bioethers". biofuel.org.uk. from the original on 1 February 2016.
  53. ^ "Council Directive 85/536/EEC of 5 December 1985 on crude-oil savings through the use of substitute fuel components in petrol". Eur-lex.europa.eu. from the original on 21 May 2011. Retrieved 14 July 2010.
  54. ^ "Impact Assessment of the Proposal for a Directive of the European Parliament and of the Council modifying Directive 98/70/EC relating to the quality of petrol and diesel fuels" (PDF). Brussels: Commission of the European Communities. 31 January 2007. (PDF) from the original on 15 July 2011. Retrieved 14 July 2010.
  55. ^ Sukla MK, Bhaskar T, Jain AK, Singal SK, Garg MO. "Bio-Ethers as Transportation Fuel: A Review" (PDF). Indian Institute of Petroleum Dehradun. (PDF) from the original on 14 October 2011. Retrieved 15 February 2014.
  56. ^ (PDF). . The European Fuel Oxygenates Association. Archived from the original (PDF) on 6 March 2014.
  57. ^ . Environmental Protection Agency. Archived from the original on 6 December 2013. Retrieved 6 March 2014.
  58. ^ "Biofuels – Types of Biofuels – Bioethers". from the original on 1 February 2016. Retrieved 30 May 2015.
  59. ^ "Sustainable aviation fuel market demand drives new product launches". Investable Universe. 4 December 2020. Retrieved 12 December 2022. Note: Investable Universe>About
  60. ^ Doliente SS, et al. (10 July 2020). "Bio-aviation Fuel: A Comprehensive Review and Analysis of the Supply Chain Components" (PDF). Frontiers in Energy Research. 8. doi:10.3389/fenrg.2020.00110.
  61. ^ "Developing Sustainable Aviation Fuel (SAF)". IATA.
  62. ^ Bauen A, Howes J, Bertuccioli L, Chudziak C (August 2009). "Review of the potential for biofuels in aviation". CiteSeerX 10.1.1.170.8750.
  63. ^ IATA (December 2023). . www.iata.org/flynetzero. Archived from the original on 24 February 2024.
  64. ^ Mark Pilling (25 March 2021). "How sustainable fuel will help power aviation's green revolution". Flight Global.
  65. ^ Ryckebosch E, Drouillon M, Vervaeren H (1 May 2011). "Techniques for transformation of biogas to biomethane". Biomass and Bioenergy. 35 (5): 1633–1645. Bibcode:2011BmBe...35.1633R. doi:10.1016/j.biombioe.2011.02.033. ISSN 0961-9534.
  66. ^ . National Non-Food Crops Centre. 4 October 2008. NNFCC 08-006. Archived from the original on 4 October 2008. Retrieved 2 January 2023.
  67. ^ Yee A (21 September 2018). "In Sweden, Trash Heats Homes, Powers Buses and Fuels Taxi Fleets". The New York Times. ISSN 0362-4331. Retrieved 14 March 2024.
  68. ^ "BIOGAS: No bull, manure can power your farm." Farmers Guardian (25 September 2009): 12. General OneFile. Gale.
  69. ^ Nagel F (2008). (PhD thesis). Swiss Federal Institute of Technology Zurich. Archived from the original on 13 March 2011.
  70. ^ a b "Biofuel from Algae: The Pros and Cons of Pond Scum". Thomasnet®. from the original on 6 April 2020. Retrieved 25 October 2020.
  71. ^ "Biomass - Offshore wind farms = seaweed = biofuel". Renewable Energy Magazine, at the heart of clean energy journalism. 14 September 2020. from the original on 27 July 2020. Retrieved 16 October 2020.
  72. ^ Greenwell HC, Laurens LM, Shields RJ, Lovitt RW, Flynn KJ (May 2010). "Placing microalgae on the biofuels priority list: a review of the technological challenges". Journal of the Royal Society, Interface. 7 (46): 703–726. doi:10.1098/rsif.2009.0322. PMC 2874236. PMID 20031983.
  73. ^ Dinh LT, Guo Y, Mannan MS (2009). "Sustainability evaluation of biodiesel production using multicriteria decision-making". Environmental Progress & Sustainable Energy. 28 (1): 38–46. Bibcode:2009EPSE...28...38D. doi:10.1002/ep.10335. S2CID 111115884.
  74. ^ Ajayebi A, Gnansounou E, Kenthorai Raman J (1 December 2013). "Comparative life cycle assessment of biodiesel from algae and jatropha: A case study of India". Bioresource Technology. 150: 429–437. Bibcode:2013BiTec.150..429A. doi:10.1016/j.biortech.2013.09.118. ISSN 0960-8524. PMID 24140355.
  75. ^ Yang J, Xu M, Zhang X, Hu Q, Sommerfeld M, Chen Y (January 2011). (PDF). Bioresource Technology. 102 (1): 159–165. Bibcode:2011BiTec.102..159Y. doi:10.1016/j.biortech.2010.07.017. PMID 20675125. Archived from the original (PDF) on 27 February 2012.
  76. ^ Cornell CB (29 March 2008). "First Algae Biodiesel Plant Goes Online: 1 April 2008". Gas 2.0. from the original on 18 June 2019. Retrieved 10 June 2008.
  77. ^ Demirbas AH (2011). "Biodiesel from oilgae, biofixation of carbon dioxide by microalgae: A solution to pollution problems". Applied Energy. 88 (10): 3541–3547. Bibcode:2011ApEn...88.3541D. doi:10.1016/j.apenergy.2010.12.050. hdl:11503/1330.
  78. ^ Demirbas AH (2009). "Inexpensive oil and fats feedstocks for production of biodiesel". Energy Education Science and Technology Part A: Energy Science and Research. 23: 1–13.
  79. ^ Rodionova M, Poudyal R, Tiwari I, Voloshin R, Zharmukhamedov S, Nam H, et al. (March 2017). "Biofuel production: Challenges and opportunities". International Journal of Hydrogen Energy. 42 (12): 8450–8461. doi:10.1016/j.ijhydene.2016.11.125.
  80. ^ Wesoff E (19 April 2017). "Hard Lessons From the Great Algae Biofuel Bubble". from the original on 5 July 2017. Retrieved 5 August 2017.
  81. ^ a b c Aro EM (January 2016). "From first generation biofuels to advanced solar biofuels". Ambio. 45 (Supplement 1): S24–S31. Bibcode:2016Ambio..45S..24A. doi:10.1007/s13280-015-0730-0. PMC 4678123. PMID 26667057.
  82. ^ a b Abdullah B, Muhammad SA, Shokravi Z, Ismail S, Kassim KA, Mahmood AN, et al. (June 2019). "Fourth generation biofuel: A review on risks and mitigation strategies". Renewable and Sustainable Energy Reviews. 107: 37–50. doi:10.1016/j.rser.2019.02.018. S2CID 116245776.
  83. ^ Lü J, Sheahan C, Fu P (2011). "Metabolic engineering of algae for fourth generation biofuels production". Energy & Environmental Science. 4 (7): 2451. doi:10.1039/c0ee00593b. ISSN 1754-5692.
  84. ^ Xu F, Li Y, Ge X, Yang L, Li Y (1 January 2018). "Anaerobic digestion of food waste – Challenges and opportunities". Bioresource Technology. 247: 1047–1058. doi:10.1016/j.biortech.2017.09.020. ISSN 0960-8524. PMID 28965912.
  85. ^ Mahmudul HM, Rasul MG, Akbar D, Narayanan R, Mofijur M (20 January 2021). "A comprehensive review of the recent development and challenges of a solar-assisted biodigester system". Science of the Total Environment. 753: 141920. doi:10.1016/j.scitotenv.2020.141920. ISSN 0048-9697. PMID 32889316.
  86. ^ Kougias PG, Angelidaki I (30 April 2018). "Biogas and its opportunities—A review". Frontiers of Environmental Science & Engineering. 12 (3): 14. doi:10.1007/s11783-018-1037-8. ISSN 2095-221X.
  87. ^ Zhang C, Su H, Baeyens J, Tan T (1 October 2014). "Reviewing the anaerobic digestion of food waste for biogas production". Renewable and Sustainable Energy Reviews. 38: 383–392. doi:10.1016/j.rser.2014.05.038. ISSN 1364-0321.
  88. ^ "Biofuel energy production". Our World in Data. Retrieved 15 August 2023.
  89. ^ "Is the biofuel industry approaching a feedstock crunch? – Analysis". IEA. Retrieved 13 March 2024.
  90. ^ Towards sustainable production and use of resources: Assessing Biofuels Archived 2016-05-13 at the Portuguese Web Archive, 2009, International Resource Panel, United Nations Environment Programme
  91. ^ "Indonesia's biodiesel drive is leading to deforestation". BBC News. 8 December 2021.
  92. ^ "Press corner". European Commission - European Commission. Retrieved 19 April 2024.
  93. ^ "Biomass Strategy 2023". GOV.UK. Retrieved 19 April 2024.
  94. ^ "Food vs fuel: Ukraine war sharpens debate on use of crops for energy". Financial Times. 12 June 2022. Archived from the original on 10 December 2022.
  95. ^ "Guest view: Global hunger fight means no biofuel". Reuters. 6 June 2022.
  96. ^ "Cutting biofuels can help avoid global food shock from Ukraine war". New Scientist. 14 March 2022.
  97. ^ Antizar-Ladislao B, Turrion-Gomez JL (September 2008). "Second-generation biofuels and local bioenergy systems". Biofuels, Bioproducts and Biorefining. 2 (5): 455–469. doi:10.1002/bbb.97. S2CID 84426763.
  98. ^ Bryngemark E (December 2019). "Second generation biofuels and the competition for forest raw materials: A partial equilibrium analysis of Sweden". Forest Policy and Economics. 109: 102022. doi:10.1016/j.forpol.2019.102022. ISSN 1389-9341. S2CID 212954432.
  99. ^ Jacob-Lopes E, Zepka LQ, Severo IA, Maroneze MM, eds. (2022). 3rd generation biofuels: disruptive technologies to enable commercial production. Woodhead Publishing series in energy. Cambridge, MA Kidlington: Woodhead Publishing, an imprint of Elsevier. ISBN 978-0-323-90971-6.
  100. ^ Magazine H. "Biofuel Made from Algae Isn't the Holy Grail We Expected". Hakai Magazine. Retrieved 31 March 2024.
  101. ^ "Palm Oil Exporter Indonesia Concerned by EU's Deforestation Law". Jakarta Globe. 22 May 2022.
  102. ^ "EU palm oil use and imports seen plummeting by 2032". Reuters. 8 December 2022.
  103. ^ Forsberg C (January 2009). "The Real Path to Green Energy: Hybrid Nuclear-Renewable Power". Bulletin of the Atomic Scientists. 65 (6): 65–71. doi:10.2968/065006007. ISSN 0096-3402.
  104. ^ a b Timothy Searchinger, et al. (29 February 2008). "Use of U.S. Croplands for Biofuels Increases Greenhouse Gases Through Emissions from Land-Use Change". Science. 319 (5867): 1238–1240. Bibcode:2008Sci...319.1238S. doi:10.1126/science.1151861. PMID 18258860. S2CID 52810681. Originally published online in Science Express on 7 February 2008 available here 2009-12-11 at the Wayback Machine
  105. ^ a b Michael Wang, Zia Haq (14 March 2008). (PDF). Argonne National Laboratory. Archived from the original (PDF) on 15 February 2013. Retrieved 7 June 2009. The published version on Science Letters is included in Searchinger E-Letter responses 2008-08-12
  106. ^ a b Gnansounou, et al. (March 2008). "Accounting for indirect land-use changes in GHG balances of biofuels: Review of current approaches" (PDF). École Polytechnique Fédérale de Lausanne. Retrieved 7 June 2009. Working Paper REF. 437.101
  107. ^ Alexander E. Farrell (13 February 2008). "Better biofuels before more biofuels". San Francisco Chronicle. Retrieved 7 June 2009.
  108. ^ Donald Sawyer (27 May 2008). "Climate change, biofuels and eco-social impacts in the Brazilian Amazon and Cerrado". Philosophical Transactions of the Royal Society. 363 (1498): 1747–1752. doi:10.1098/rstb.2007.0030. PMC 2373893. PMID 18267903. Published on line 2008-02-11.
  109. ^ Naylor, et al. (November 2007). "The Ripple Effect: Biofuels, Food Security, and the Environment". Environment. Retrieved 7 June 2009.
  110. ^ Renton Righelato, Dominick V. Spracklen (17 August 2007). "Carbon Mitigation by Biofuels or by Saving and Restoring Forests?". Science. 317 (5840): 902. doi:10.1126/science.1141361. PMID 17702929. S2CID 40785300.

Sources edit

  • Avril Group, ed. (2015). (PDF) (Report). Paris: Avril. p. 65. Archived from the original (PDF) on 26 October 2020. Retrieved 11 August 2022.
  • EurObserv (July 2014). Biofuel barometer (PDF) (Report).

External links edit

  • Biofuels Journal
  • Alternative Fueling Station Locator 14 July 2008 at the Wayback Machine (EERE)
  • by the United Nations Environment Programme, October 2009.
  • on NetRegs.gov.uk
  • —Natural gas requires the least water to produce energy, some biofuels the most, according to a new study.
  • – European Union Biofuels Standardization
  • Biofuels from Biomass: Technology and Policy Considerations Thorough overview from MIT
  • The Guardian news on biofuels
  • – links to the 87 US Clean Cities coalitions, as of 2004.
  • by the University of Michigan's Center for Sustainable Systems
  • Learn Biofuels – Educational Resource for Students

biofuel, this, article, about, mainly, liquid, gaseous, fuels, used, transport, other, applications, bioenergy, fuel, that, produced, over, short, time, span, from, biomass, rather, than, very, slow, natural, processes, involved, formation, fossil, fuels, such. This article is about mainly liquid or gaseous fuels used for transport For other applications see Bioenergy Biofuel is a fuel that is produced over a short time span from biomass rather than by the very slow natural processes involved in the formation of fossil fuels such as oil Biofuel can be produced from plants or from agricultural domestic or industrial biowaste 1 Biofuels are mostly used for transportation but can also be used for heating and electricity 2 173 3 Biofuels and bioenergy in general are regarded as a renewable energy source 4 11 The use of biofuel has been subject to criticism regarding the food vs fuel debate varied assessments of their sustainability and possible deforestation and biodiversity loss as a result of biofuel production A sample of biodiesel In general biofuels emit fewer greenhouse gas emissions when burned in an engine and are generally considered carbon neutral fuels as the carbon emitted has been captured from the atmosphere by the crops used in production 5 However life cycle assessments of biofuels have shown large emissions associated with the potential land use change required to produce additional biofuel feedstocks 6 7 The outcomes of lifecycle assessments LCAs for biofuels are highly situational and dependent on many factors including the type of feedstock production routes data variations and methodological choices This could be added to emphasize the complexity and variability in assessing the environmental impacts of biofuels 8 Estimates about the climate impact from biofuels vary widely based on the methodology and exact situation examined 6 Therefore the climate change mitigation potential of biofuel varies considerably in some scenarios emission levels are comparable to fossil fuels and in other scenarios the biofuel emissions result in negative emissions Global demand for biofuels is predicted to increase by 56 over 2022 2027 9 By 2027 worldwide biofuel production is expected to supply 5 4 of the world s fuels for transport including 1 of aviation fuel 10 Demand for aviation biofuel is forecast to increase 11 12 The two most common types of biofuel are bioethanol and biodiesel Brazil is the largest producer of bioethanol while the EU is the largest producer of biodiesel The energy content in the global production of bioethanol and biodiesel is 2 2 and 1 8 EJ per year respectively 13 Bioethanol is an alcohol made by fermentation mostly from carbohydrates produced in sugar or starch crops such as maize sugarcane or sweet sorghum Cellulosic biomass derived from non food sources such as trees and grasses is also being developed as a feedstock for ethanol production Ethanol can be used as a fuel for vehicles in its pure form E100 but it is usually used as a gasoline additive to increase octane ratings and improve vehicle emissions Biodiesel is produced from oils or fats using transesterification It can be used as a fuel for vehicles in its pure form B100 but it is usually used as a diesel additive to reduce levels of particulates carbon monoxide and hydrocarbons from diesel powered vehicles 14 Contents 1 Terminology 1 1 Conventional biofuels first generation 1 2 Advanced biofuels 2 Types 2 1 Liquid 2 1 1 Ethanol 2 1 2 Other bioalcohols 2 1 3 Biodiesel 2 1 4 Green diesel 2 1 5 Straight vegetable oil 2 1 6 Biogasoline 2 1 7 Bioethers 2 1 8 Aviation biofuel 2 2 Gaseous 2 2 1 Biogas and biomethane 2 2 2 Syngas 2 3 Solid 3 Research into other types 3 1 Algae based biofuels 3 2 Electrofuels and solar fuels 4 Bio digesters 5 Extent of production and use 6 Issues 6 1 Environmental impacts 6 2 Indirect land use change impacts of biofuels 7 See also 8 References 8 1 Sources 9 External linksTerminology editSee also Biomass energy Terminology nbsp Types and generation of biofuels The term biofuel is used in different ways One definition is Biofuels are biobased products in solid liquid or gaseous forms They are produced from crops or natural products such as wood or agricultural residues such as molasses and bagasse 2 173 Other publications reserve the term biofuel for liquid or gaseous fuels used for transportation 3 The IPCC Sixth Assessment Report defines biofuel as A fuel generally in liquid form produced from biomass Biofuels include bioethanol from sugarcane sugar beet or maize and biodiesel from canola or soybeans 15 1795 It goes on to define biomass in this context as organic material excluding the material that is fossilised or embedded in geological formations 15 1795 This means that coal or other fossil fuels is not a form of biomass in this context Conventional biofuels first generation edit First generation biofuels also denoted as conventional biofuels are made from food crops grown on arable land 16 17 447 The crop s sugar starch or oil content is converted into biodiesel or ethanol using transesterification or yeast fermentation 18 Advanced biofuels edit To avoid a food versus fuel dilemma second generation biofuels and third generation biofuels also called advanced biofuels or sustainable biofuels or drop in biofuels are made from feedstocks which do not directly compete with food or feed crop such as waste products and energy crops 19 A wide range of waste feedstocks such as those derived from agriculture and forestry activities like rice straw rice husk wood chips and sawdust can be used to produce advanced biofuels through biochemical and thermochemical processes 17 448 The feedstock used to make the fuels either grow on arable land but are byproducts of the main crop or they are grown on marginal land Second generation feedstocks also include straw bagasse perennial grasses jatropha waste vegetable oil municipal solid waste and so forth 20 Types editLiquid edit Ethanol edit Main article Ethanol fuel Biologically produced alcohols most commonly ethanol and less commonly propanol and butanol are produced by the action of microorganisms and enzymes through the fermentation of sugars or starches easiest to produce or cellulose more difficult to produce The IEA estimates that ethanol production used 20 of sugar supplies and 13 of corn supplies in 2021 21 Ethanol fuel is the most common biofuel worldwide particularly in Brazil Alcohol fuels are produced by fermentation of sugars derived from wheat corn sugar beets sugar cane molasses and any sugar or starch from which alcoholic beverages such as whiskey can be made such as potato and fruit waste etc Production methods used are enzyme digestion to release sugars from stored starches fermentation of the sugars distillation and drying The distillation process requires significant energy input to generate heat Heat is sometimes generated with unsustainable natural gas fossil fuel but cellulosic biomass such as bagasse is the most common fuel in Brazil while pellets wood chips and also waste heat are more common in Europe Corn to ethanol and other food stocks has led to the development of cellulosic ethanol 22 Other bioalcohols edit Methanol is currently produced from natural gas a non renewable fossil fuel In the future it is hoped to be produced from biomass as biomethanol This is technically feasible but the production is currently being postponed for concerns that the economic viability is still pending 23 The methanol economy is an alternative to the hydrogen economy to be contrasted with today s hydrogen production from natural gas Butanol C4 H9 OH is formed by ABE fermentation acetone butanol ethanol and experimental modifications of the process show potentially high net energy gains with biobutanol as the only liquid product Biobutanol is often claimed to provide a direct replacement for gasoline because it will produce more energy than ethanol and allegedly can be burned straight in existing gasoline engines without modification to the engine or car 24 is less corrosive and less water soluble than ethanol and could be distributed via existing infrastructures Escherichia coli strains have also been successfully engineered to produce butanol by modifying their amino acid metabolism 25 One drawback to butanol production in E coli remains the high cost of nutrient rich media however recent work has demonstrated E coli can produce butanol with minimal nutritional supplementation 26 Biobutanol is sometimes called biogasoline which is incorrect as it is chemically different being an alcohol and not a hydrocarbon like gasoline Biodiesel edit nbsp Biofuel pumps 2010 Main article Biodiesel Further information Biodiesel around the world Biodiesel is the most common biofuel in Europe It is produced from oils or fats using transesterification and is a liquid similar in composition to fossil mineral diesel Chemically it consists mostly of fatty acid methyl or ethyl esters FAMEs 27 Feedstocks for biodiesel include animal fats vegetable oils soy rapeseed jatropha mahua mustard flax sunflower palm oil hemp field pennycress Pongamia pinnata and algae Pure biodiesel B100 also known as neat biodiesel currently reduces emissions with up to 60 compared to diesel Second generation B100 28 As of 2020 update researchers at Australia s CSIRO have been studying safflower oil as an engine lubricant and researchers at Montana State University s Advanced Fuels Center in the US have been studying the oil s performance in a large diesel engine with results described as a breakthrough 29 nbsp Targray Biofuels Division railcar transporting Biodiesel Biodiesel can be used in any diesel engine and modified equipment when mixed with mineral diesel It can also be used in its pure form B100 in diesel engines but some maintenance and performance problems may occur during wintertime utilization since the fuel becomes somewhat more viscous at lower temperatures depending on the feedstock used 30 Electronically controlled common rail and Unit Injector type systems from the late 1990s onwards can only use biodiesel blended with conventional diesel fuel These engines have finely metered and atomized multiple stage injection systems that are very sensitive to the viscosity of the fuel Many current generation diesel engines are designed to run on B100 without altering the engine itself although this depends on the fuel rail design Since biodiesel is an effective solvent and cleans residues deposited by mineral diesel engine filters may need to be replaced more often as the biofuel dissolves old deposits in the fuel tank and pipes It also effectively cleans the engine combustion chamber of carbon deposits helping to maintain efficiency Biodiesel is an oxygenated fuel meaning it contains a reduced amount of carbon and higher hydrogen and oxygen content than fossil diesel This improves the combustion of biodiesel and reduces the particulate emissions from unburnt carbon However using pure biodiesel may increase NOx emissions 31 Biodiesel is also safe to handle and transport because it is non toxic and biodegradable and has a high flash point of about 300 F 148 C compared to petroleum diesel fuel which has a flash point of 125 F 52 C 32 In many European countries a 5 biodiesel blend is widely used and is available at thousands of gas stations 33 34 In France biodiesel is incorporated at a rate of 8 in the fuel used by all French diesel vehicles 35 Avril Group produces under the brand Diester a fifth of 11 million tons of biodiesel consumed annually by the European Union 36 It is the leading European producer of biodiesel 35 Green diesel edit Main article Biodiesel production Green diesel can be produced combination of biochemical and thermochemical processes Conventional green diesel is produced through hydroprocessing biological oil feedstocks such as vegetable oils and animal fats 37 38 Recently it is produced using series of thermochemical processes such as pyrolysis and hydroprocessing In the thermochemical route syngas produced from gasification bio oil produced from pyrolysis or biocrude produced from hydrothermal liquefaction is upgraded to green diesel using hydroprocessing 39 40 41 Hydroprocessing is the process of using hydrogen to reform a molecular structure For example hydrocracking which is a widely used hydroprocessing technique in refineries is used at elevated temperatures and pressure in the presence of a catalyst to break down larger molecules such as those found in vegetable oils into shorter hydrocarbon chains used in diesel engines 42 Green diesel may also be called renewable diesel drop in biodiesel hydrotreated vegetable oil HVO fuel 42 or hydrogen derived renewable diesel 38 Unlike biodiesel green diesel has exactly the same chemical properties as petroleum based diesel 42 43 It does not require new engines pipelines or infrastructure to distribute and use but has not been produced at a cost that is competitive with petroleum 38 Gasoline versions are also being developed 44 Green diesel is being developed in Louisiana and Singapore by ConocoPhillips Neste Oil Valero Dynamic Fuels and Honeywell UOP 38 45 as well as Preem in Gothenburg Sweden creating what is known as Evolution Diesel 46 Straight vegetable oil edit nbsp A biofuel truck in 2009 47 Main article Vegetable oil fuel Straight unmodified edible vegetable oil is generally not used as fuel but lower quality oil has been used for this purpose Used vegetable oil is increasingly being processed into biodiesel or more rarely cleaned of water and particulates and then used as a fuel The IEA estimates that biodiesel production used 17 of global vegetable oil supplies in 2021 21 Oils and fats reacted with 10 pounds of a short chain alcohol usually methanol in the presence of a catalyst usually sodium hydroxide NaOH can be hydrogenated to give a diesel substitute 48 The resulting product is a straight chain hydrocarbon with a high cetane number low in aromatics and sulfur and does not contain oxygen Hydrogenated oils can be blended with diesel in all proportions They have several advantages over biodiesel including good performance at low temperatures no storage stability problems and no susceptibility to microbial attack 49 Biogasoline edit Main article Biogasoline Biogasoline can be produced biologically and themochemically Using biologicalical methods a study led by Professor Lee Sang yup at the Korea Advanced Institute of Science and Technology KAIST and published in the international science journal Nature used modified E coli fed with glucose found in plants or other non food crops to produce biogasoline with the produced enzymes The enzymes converted the sugar into fatty acids and then turned these into hydrocarbons that were chemically and structurally identical to those found in commercial gasoline fuel 50 The thermochemical approach of producing biogasoline are similar to those used to produced biodiesel 39 40 41 Biogasoline may also be called drop in gasoline or renewable gasoline Bioethers edit nbsp Neat ethanol on the left A gasoline on the right G at a filling station in Brazil in 2008 Bioethers also referred to as fuel ethers or oxygenated fuels are cost effective compounds that act as octane rating enhancers Bioethers are produced by the reaction of reactive iso olefins such as iso butylene with bioethanol 51 attribution needed Bioethers are created from wheat or sugar beets and also be produced from the waste glycerol that results from the production of biodiesel 52 They also enhance engine performance while significantly reducing engine wear and toxic exhaust emissions By greatly reducing the amount of ground level ozone emissions they contribute to improved air quality 53 54 In transportation fuel there are six ether additives dimethyl ether DME diethyl ether DEE methyl tert butyl ether MTBE ethyl tert butyl ether ETBE tert amyl methyl ether TAME and tert amyl ethyl ether TAEE 55 The European Fuel Oxygenates Association identifies MTBE and ETBE as the most commonly used ethers in fuel to replace lead Ethers were introduced in Europe in the 1970s to replace the highly toxic compound 56 Although Europeans still use bioether additives the U S Energy Policy Act of 2005 lifted a requirement for reformulated gasoline to include an oxygenate leading to less MTBE being added to fuel 57 Although bioethers are likely to replace ethers produced from petroleum in the UK it is highly unlikely they will become a fuel in and of itself due to the low energy density 58 Aviation biofuel edit This section is an excerpt from Aviation biofuel edit nbsp Refueling an Airbus A320 with biofuel in 2011 An aviation biofuel also known as bio jet fuel 59 or bio aviation fuel BAF 60 is a biofuel used to power aircraft and is a sustainable aviation fuel SAF The International Air Transport Association IATA considers it a key element in reducing the environmental impact of aviation 61 Aviation biofuel is used to decarbonize medium and long haul air travel These types of travel generate the most emissions and could extend the life of older aircraft types by lowering their carbon footprint Synthetic paraffinic kerosene SPK refers to any non petroleum based fuel designed to replace kerosene jet fuel which is often but not always made from biomass Biofuels are biomass derived fuels from plants animals or waste depending on which type of biomass is used they could lower CO2 emissions by 20 98 compared to conventional jet fuel 62 The first test flight using blended biofuel was in 2008 and in 2011 blended fuels with 50 biofuels were allowed on commercial flights In 2023 SAF production was 600 million liters representing 0 2 of global jet fuel use 63 Aviation biofuel can be produced from plant or animal sources such as Jatropha algae tallows waste oils palm oil Babassu and Camelina bio SPK from solid biomass using pyrolysis processed with a Fischer Tropsch process FT SPK with an alcohol to jet ATJ process from waste fermentation or from synthetic biology through a solar reactor Small piston engines can be modified to burn ethanol Sustainable biofuels are an alternative to electrofuels 64 Sustainable aviation fuel is certified as being sustainable by a third party organisation Gaseous edit Biogas and biomethane edit nbsp Biogas plant in 2007 Main article Biogas Biogas is a mixture composed primarily of methane and carbon dioxide produced by the process of anaerobic digestion of organic material by micro organisms Other trace components of this mixture includes water vapor hydrogen sulfide siloxanes hydrocarbons ammonia oxygen carbon monoxide and nitrogen 65 66 It can be produced either from biodegradable waste materials or by the use of energy crops fed into anaerobic digesters to supplement gas yields The solid byproduct digestate can be used as a biofuel or a fertilizer When CO2 and other impurities are removed from biogas it is called biomethane The CO2 can also be combined with hydrogen in methanation to form more methane Biogas can be recovered from mechanical biological treatment waste processing systems Landfill gas a less clean form of biogas is produced in landfills through naturally occurring anaerobic digestion If it escapes into the atmosphere it acts as a greenhouse gas In Sweden waste to energy power plants capture methane biogas from garbage and use it power transport systems 67 Farmers can produce biogas from cattle manure via anaerobic digesters 68 Syngas edit Main article Gasification Syngas a mixture of carbon monoxide hydrogen and various hydrocarbons is produced by partial combustion of biomass combustion with an amount of oxygen that is not sufficient to convert the biomass completely to carbon dioxide and water 49 Before partial combustion the biomass is dried and sometimes pyrolysed Syngas is more efficient than direct combustion of the original biofuel more of the energy contained in the fuel is extracted Syngas may be burned directly in internal combustion engines turbines or high temperature fuel cells 69 The wood gas generator a wood fueled gasification reactor can be connected to an internal combustion engine Syngas can be used to produce methanol dimethyl ether and hydrogen or converted via the Fischer Tropsch process to produce a diesel substitute or a mixture of alcohols that can be blended into gasoline Gasification normally relies on temperatures greater than 700 C Lower temperature gasification is desirable when co producing biochar but results in syngas polluted with tar Solid edit Main article Solid fuel Biomass The term biofuels is also used for solid fuels that are made from biomass even though this is less common 3 Research into other types editAlgae based biofuels edit Main articles Algaculture and Algae fuel Algae can be produced in ponds or tanks on land and out at sea 70 71 Algal fuels have high yields 72 a high ignition point 73 can be grown with minimal impact on fresh water resources 74 75 76 can be produced using saline water and wastewater and are biodegradable and relatively harmless to the environment if spilled 77 78 However production requires large amounts of energy and fertilizer the produced fuel degrades faster than other biofuels and it does not flow well in cold temperatures 70 79 By 2017 due to economic considerations most efforts to produce fuel from algae have been abandoned or changed to other applications 80 Third and fourth generation biofuels also include biofuels that are produced by bioengineered organisms i e algae and cyanobacteria 81 Algae and cyanobacteria will use water carbon dioxide and solar energy to produce biofuels 81 This method of biofuel production is still at the research level The biofuels that are secreted by the bioengineered organisms are expected to have higher photon to fuel conversion efficiency compared to older generations of biofuels 81 One of the advantages of this class of biofuels is that the cultivation of the organisms that produce the biofuels does not require the use of arable land 82 The disadvantages include the cost of cultivating the biofuel producing organisms being very high 82 Electrofuels and solar fuels edit Electrofuels citation needed and solar fuels may or may not be biofuels depending on whether they contain biological elements Electrofuels are made by storing electrical energy in the chemical bonds of liquids and gases The primary targets are butanol biodiesel and hydrogen but include other alcohols and carbon containing gases such as methane and butane A solar fuel is a synthetic chemical fuel produced from solar energy Light is converted to chemical energy typically by reducing protons to hydrogen or carbon dioxide to organic compounds 83 Bio digesters editA bio digester is a mechanized toilet that uses decomposition and sedimentation to turn human waste into a renewable fuel called biogas Biogas can be made from substances like agricultural waste and sewage 84 85 The bio digester uses a process called anaerobic digestion to produce biogas Anaerobic digestion uses a chemical process to break down organic matter with the use of microorganisms in the absence of oxygen to produce biogas 86 The processes involved in anaerobic respiration are hydrolysis acidogenesis acetogenesis and methanogenesis 87 Extent of production and use edit nbsp Biofuel energy production 2022 88 nbsp Biofuel production by region Global biofuel production was 81 Mtoe in 2017 which represented an annual increase of about 3 compared to 2010 4 12 In 2017 the US was the largest biofuel producer in the world producing 37 Mtoe followed by Brazil and South America at 23 Mtoe and Europe mainly Germany at 12 Mtoe 4 12 An assessment from 2017 found that Biofuels will never be a major transport fuel as there is just not enough land in the world to grow plants to make biofuel for all vehicles It can however be part of an energy mix to take us into a future of renewable energy 4 11 In 2021 worldwide biofuel production provided 4 3 of the world s fuels for transport including a very small amount of aviation biofuel 10 By 2027 worldwide biofuel production is expected to supply 5 4 of the world s fuels for transport including 1 of aviation fuel 10 The US Europe Brazil and Indonesia are driving the majority of biofuel consumption growth This demand for biodiesel renewable diesel and biojet fuel is projected to increase by 44 21 billion litres over 2022 2027 89 Issues edit nbsp Wheat fields in the USA wheat is grown for food but also for biofuel production This section is an excerpt from Issues relating to biofuels edit This article needs to be updated Please help update this article to reflect recent events or newly available information March 2024 This article has an unclear citation style The references used may be made clearer with a different or consistent style of citation and footnoting July 2023 Learn how and when to remove this message Issues relating to biofuel are social economic environmental and technical problems that may arise from biofuel production and use Social and economic issues include the food vs fuel debate and the need to develop responsible policies and economic instruments to ensure sustainable biofuel production Farming for biofuels feedstock can be detrimental to the environment if not done sustainably Environmental concerns include deforestation biodiversity loss and soil erosion as a result of land clearing for biofuels agriculture While biofuels can contribute to reduction in global carbon emissions indirect land use change for biofuel production can have the inverse effect Technical issues include possible modifications necessary to run the engine on biofuel as well as energy balance and efficiency The International Resource Panel outlined the wider and interrelated factors that need to be considered when deciding on the relative merits of pursuing one biofuel over another 90 The IRP concluded that not all biofuels perform equally in terms of their effect on climate energy security and ecosystems and suggested that environmental and social effects need to be assessed throughout the entire life cycle Environmental impacts edit Further information Sustainable biofuels nbsp Deforestation in Indonesia to make way for an oil palm plantation 91 Estimates about the climate impact from biofuels vary widely based on the methodology and exact situation examined 6 In general biofuels emit fewer greenhouse gas emissions when burned in an engine and are generally considered carbon neutral fuels as the carbon they emit has been captured from the atmosphere by the crops used in biofuel production 5 They can have greenhouse gas emissions ranging from as low as 127 1 gCO2eq per MJ when carbon capture is incorporated into their production to those exceeding 95 gCO2eq per MJ when land use change is significant 40 41 Several factors are responsible for the variation in emission numbers of biofuel such as feedstock and its origin fuel production technique system boundary definitions and energy sources 41 However many government policies such as those by European Union and the UK require that biofuels have at least 65 greenhouse gas emissions savings or 70 if it is renewable fuels of non biological origins relative to fossil fuels 92 93 Life cycle assessments of first generation biofuels have shown large emissions associated with the potential land use change required to produce additional biofuel feedstocks 6 7 If no land use change is involved first generation biofuels can on average have lower emissions than fossil fuels 6 However biofuel production can compete with foodcrop production Up to 40 of corn produced in the United States is used to make ethanol 94 and worldwide 10 of all grain is turned into biofuel 95 A 50 reduction in grain used for biofuels in the US and Europe would replace all of Ukraine s grain exports 96 Several studies have shown that reductions in emissions from biofuels are achieved at the expense of other impacts such as acidification eutrophication water footprint and biodiversity loss 6 The use of second generation biofuels is thought to increase environmental sustainability since the non food part of plants is being used to produce second generation biofuels instead of being disposed 97 But the use of second generation biofuels increases the competition for lignocellulosic biomass increasing the cost of these biofuels 98 Third generation biofuels produced from Algae in theory shouldn t have as negative an impact on the environment than first or second generation biofuels due to lower changes in land use and not requiring pesticide use for production 99 When looking at the data however it has been shown that the environmental cost to produce the infrastructure and energy required for third generation biofuel production is higher than the benefits provided from the biofuels use 100 The European Commission has officially approved a measure to phase out palm oil based biofuels by 2030 101 102 Unsustainable palm oil agriculture has caused significant environmental and social problems including deforestation and pollution The production of biofuels can be very energy intensive which if generated from non renewable sources can heavily mitigate the benefits gained through biofuel use A solution proposed to solve this issue is to supply biofuel production facilities with excess nuclear energy which can supplement the energy provided by fossil fuels 103 This can provide a carbon inexpensive solution to help reduce the environmental impacts of biofuel production Indirect land use change impacts of biofuels edit This section is an excerpt from Indirect land use change impacts of biofuels edit This article needs to be updated Please help update this article to reflect recent events or newly available information August 2021 nbsp Brazilian cerrado nbsp Amazon rainforest The indirect land use change impacts of biofuels also known as ILUC or iLUC pronounced as i luck relates to the unintended consequence of releasing more carbon emissions due to land use changes around the world induced by the expansion of croplands for ethanol or biodiesel production in response to the increased global demand for biofuels 104 105 As farmers worldwide respond to higher crop prices in order to maintain the global food supply and demand balance pristine lands are cleared to replace the food crops that were diverted elsewhere to biofuels production Because natural lands such as rainforests and grasslands store carbon in their soil and biomass as plants grow each year clearance of wilderness for new farms translates to a net increase in greenhouse gas emissions Due to this off site change in the carbon stock of the soil and the biomass indirect land use change has consequences in the greenhouse gas GHG balance of a biofuel 104 105 106 107 Other authors have also argued that indirect land use changes produce other significant social and environmental impacts affecting biodiversity water quality food prices and supply land tenure worker migration and community and cultural stability 106 108 109 110 See also edit nbsp Renewable energy portal nbsp Energy portal nbsp Biology portal nbsp Technology portal nbsp Ecology portal Bioenergy Europe BioEthanol for Sustainable Transport Biofuels Center of North Carolina Biogas powerplant International Renewable Energy Agency List of biofuel companies and researchers List of vegetable oils used for biofuel Renewable energy by country Renewable Energy Transition Residue to product ratio Sustainable aviation fuel Sustainable transport Table of biofuel crop yieldsReferences edit Biofuel Definition Types amp Pros and Cons Britannica www britannica com 18 March 2024 Retrieved 2 April 2024 a b T M Letcher ed 2020 Chapter 9 Biofuels for transport Future energy improved sustainable and clean options for our planet 3rd ed Amsterdam Netherlands ISBN 978 0 08 102887 2 OCLC 1137604985 a href Template Cite book html title Template Cite book cite book a CS1 maint location missing publisher link a b c Biofuels explained U S Energy Information Administration EIA www eia gov Retrieved 24 January 2023 a b c d T M Letcher ed 2020 Chapter1 Introduction With a Focus on Atmospheric Carbon Dioxide and Climate Change Future energy improved sustainable and clean options for our planet 3rd ed Amsterdam Netherlands ISBN 978 0 08 102887 2 OCLC 1137604985 a href Template Cite book html title Template Cite book cite book a CS1 maint location missing publisher link a b Lewandrowski J Rosenfeld J Pape D Hendrickson T Jaglo K Moffroid K 25 March 2019 The greenhouse gas benefits of corn ethanol assessing recent evidence Biofuels 11 3 Informa UK Limited 361 375 doi 10 1080 17597269 2018 1546488 ISSN 1759 7269 S2CID 134824935 a b c d e f Jeswani HK Chilvers A Azapagic A November 2020 Environmental sustainability of biofuels a review Proceedings of the Royal Society A Mathematical Physical and Engineering Sciences 476 2243 20200351 Bibcode 2020RSPSA 47600351J doi 10 1098 rspa 2020 0351 PMC 7735313 PMID 33363439 a b Lark TJ Hendricks NP Smith A Pates N Spawn Lee SA Bougie M et al March 2022 Environmental outcomes of the US Renewable Fuel Standard Proceedings of the National Academy of Sciences of the United States of America 119 9 Bibcode 2022PNAS 11901084L doi 10 1073 pnas 2101084119 PMC 8892349 PMID 35165202 Jeswani HK Chilvers A Azapagic A November 2020 Environmental sustainability of biofuels a review Proceedings of the Royal Society A Mathematical Physical and Engineering Sciences 476 2243 Bibcode 2020RSPSA 47600351J doi 10 1098 rspa 2020 0351 ISSN 1364 5021 PMC 7735313 PMID 33363439 Biofuel is approaching a feedstock crunch How bad And what must be done Energy Post 23 January 2023 Retrieved 14 March 2024 a b c Transport biofuels Renewables 2022 Analysis IEA Retrieved 30 January 2023 Biofuel is approaching a feedstock crunch How bad And what must be done Energy Post 23 January 2023 Retrieved 30 January 2023 How to scale Sustainable Aviation Fuel in the next decade World Economic Forum Retrieved 30 January 2023 Renewables Report 2022 IEA Bayetero CM Yepez CM Cevallos IB Rueda EH January 2022 Effect of the use of additives in biodiesel blends on the performance and opacity of a diesel engine Materials Today Proceedings Advances in Mechanical Engineering Trends 49 93 99 doi 10 1016 j matpr 2021 07 478 ISSN 2214 7853 S2CID 238787289 a b IPCC 2022 Annex I Glossary van Diemen R J B R Matthews V Moller J S Fuglestvedt V Masson Delmotte C Mendez A Reisinger S Semenov eds In IPCC 2022 Climate Change 2022 Mitigation of Climate Change Contribution of Working Group III to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change P R Shukla J Skea R Slade A Al Khourdajie R van Diemen D McCollum M Pathak S Some P Vyas R Fradera M Belkacemi A Hasija G Lisboa S Luz J Malley eds Cambridge University Press Cambridge UK and New York NY USA doi 10 1017 9781009157926 020 Cavelius P Engelhart Straub S Mehlmer N Lercher J Awad D Bruck T 30 March 2023 The potential of biofuels from first to fourth generation PLOS Biology 21 3 e3002063 doi 10 1371 journal pbio 3002063 ISSN 1545 7885 PMC 10063169 PMID 36996247 a b T M Letcher ed 2020 Chapter 21 Energy from biomass Future energy improved sustainable and clean options for our planet 3rd ed Amsterdam Netherlands ISBN 978 0 08 102887 2 OCLC 1137604985 a href Template Cite book html title Template Cite book cite book a CS1 maint location missing publisher link What are and who s making 2G 3G and 4G biofuels Biofuels Digest biofuels biodiesel ethanol algae jatropha green gasoline green diesel and biocrude daily news 21 May 2010 Archived from the original on 21 May 2010 European Parliament Advanced biofuels PDF Retrieved 19 April 2024 Biofuels Second Generation Biofuels biofuel org uk Archived from the original on 15 July 2019 Retrieved 18 January 2018 a b Is the biofuel industry approaching a feedstock crunch Analysis IEA Retrieved 2 January 2023 Houghton J Weatherwax S Ferrell J 7 June 2006 Breaking the biological barriers to cellulosic ethanol a joint research agenda Report Washington DC United States EERE Publication and Product Library doi 10 2172 1218382 Borjesson P Lundgren J Ahlgren S Nystrom I 18 June 2013 Dagens och framtidens hallbara biodrivmedel underlagsrapport fran f3 till utredningen om fossilfri fordonstrafik Today s and the future s sustainable biofuels background report from f3 to the inquiry into fossil free vehicle traffic Report in Swedish Vol 13 The Swedish Knowledge Centre for Renewable Transportation Fuels p 170 ButylFuel LLC Main Page Butanol com 15 August 2005 Archived from the original on 10 July 2019 Retrieved 14 July 2010 Evans J 14 January 2008 Biofuels aim higher Biofuels Bioproducts and Biorefining BioFPR Archived from the original on 10 August 2009 Retrieved 3 December 2008 Pontrelli S Fricke RC Sakurai SS Putri SP Fitz Gibbon S Chung M et al September 2018 Directed strain evolution restructures metabolism for 1 butanol production in minimal media Metabolic Engineering 49 153 163 doi 10 1016 j ymben 2018 08 004 PMID 30107263 Fukuda H Kondo A Noda H January 2001 Biodiesel fuel production by transesterification of oils Journal of Bioscience and Bioengineering 92 5 405 416 doi 10 1016 s1389 1723 01 80288 7 PMID 16233120 Perstop Press release Verdis Polaris Aura second generation B100 The advanced green one Archived from the original on 4 August 2014 Retrieved 21 June 2014 Lee T 7 June 2020 Safflower oil hailed by scientists as possible recyclable biodegradable replacement for petroleum ABC News Landline Australian Broadcasting Corporation Archived from the original on 7 June 2020 Retrieved 7 June 2020 Alternative Fuels Data Center Biodiesel Blends afdc energy gov Retrieved 31 March 2022 Nylund NO Koponen K 2012 Fuel and Technology Alternatives for Buses Overall Energy Efficiency and Emission Performance IEA Bioenergy Task 46 PDF Report VTT Technical Research Centre of Finland Archived from the original PDF on 16 February 2020 Possibly the new emission standards Euro VI EPA 10 will lead to reduced NOx levels also when using B100 Biofuels Facts Hempcar org Archived from the original on 20 May 2011 Retrieved 14 July 2010 ADM Biodiesel Hamburg Leer Mainz Biodiesel de Archived from the original on 2 August 2009 Retrieved 14 July 2010 RRI Limited for Biodiesel Filling Stations Welcome to Biodiesel Filling Stations Biodieselfillingstations co uk Archived from the original on 14 July 2018 Retrieved 14 July 2010 a b Avril Group Activity Report 2014 p 58 EurObserv 2014 p 4 Brown R Holmgren J Fast Pyrolysis and Bio Oil Upgrading PDF Archived PDF from the original on 5 January 2012 Retrieved 15 March 2012 a b c d Alternative amp Advanced Fuels US Department of Energy Archived from the original on 27 October 2012 Retrieved 7 March 2012 a b Technology Comsyn www comsynproject eu Retrieved 19 April 2024 a b c Lilonfe S Dimitriou I Davies B Abdul Manan AF McKechnie J 1 January 2024 Comparative techno economic and life cycle analyses of synthetic drop in fuel production from UK wet biomass Chemical Engineering Journal 479 147516 doi 10 1016 j cej 2023 147516 ISSN 1385 8947 a b c d Lilonfe S Davies B Abdul Manan AF Dimitriou I McKechnie J 17 April 2024 A review of techno economic analyses and life cycle greenhouse gas emissions of biomass to hydrocarbon drop in fuels Sustainable Production and Consumption doi 10 1016 j spc 2024 04 016 ISSN 2352 5509 a b c Knothe G June 2010 Biodiesel and renewable diesel a comparison Progress in Energy and Combustion Science 36 3 364 373 doi 10 1016 j pecs 2009 11 004 Archived from the original on 6 November 2012 Retrieved 23 August 2012 Green Diesel v Biodiesel Archived from the original on 5 August 2018 Retrieved 5 August 2018 Jessica E Breakthroughs in Green Gasoline Production Biomass Magazine Archived from the original on 11 March 2012 Retrieved 14 August 2012 Albrecht KO Hallen RT March 2011 A Brief Literature Overview of Various Routes to Biorenewable Fuels from Lipids for the National Alliance of Advanced Biofuels and Bio products NAAB Consortium PDF Report Prepared by the US Department of Energy Archived PDF from the original on 12 July 2012 Retrieved 23 August 2012 Preem makes major investment in green diesel at the Port of Gothenburg Port of Gothenburg August 2014 Archived from the original on 1 August 2014 Wal Mart To Test Hybrid Trucks Sustainable Business 3 February 2009 Archived from the original on 8 May 2014 Retrieved 8 May 2014 Alternative Fuels Data Center Biodiesel Production and Distribution afdc energy gov Retrieved 31 March 2022 a b Evans G 14 April 2008 Liquid Transport Biofuels Technology Status Report Report National Non Food Crops Centre Archived from the original on 11 June 2008 Liquid Transport Fuels amp Lubes South Korean scientists use E coli to make gasoline Report Fuels amp Lubes Daily 4 November 2013 Archived from the original on 7 September 2022 Rock K Korpelshoek M 2007 Bioethers Impact on the Gasoline Pool Digital Refining Archived from the original on 14 November 2016 Retrieved 15 February 2014 Biofuels Types of Biofuels Bioethers biofuel org uk Archived from the original on 1 February 2016 Council Directive 85 536 EEC of 5 December 1985 on crude oil savings through the use of substitute fuel components in petrol Eur lex europa eu Archived from the original on 21 May 2011 Retrieved 14 July 2010 Impact Assessment of the Proposal for a Directive of the European Parliament and of the Council modifying Directive 98 70 EC relating to the quality of petrol and diesel fuels PDF Brussels Commission of the European Communities 31 January 2007 Archived PDF from the original on 15 July 2011 Retrieved 14 July 2010 Sukla MK Bhaskar T Jain AK Singal SK Garg MO Bio Ethers as Transportation Fuel A Review PDF Indian Institute of Petroleum Dehradun Archived PDF from the original on 14 October 2011 Retrieved 15 February 2014 What are Bio Ethers PDF The European Fuel Oxygenates Association Archived from the original PDF on 6 March 2014 Gasoline Environmental Protection Agency Archived from the original on 6 December 2013 Retrieved 6 March 2014 Biofuels Types of Biofuels Bioethers Archived from the original on 1 February 2016 Retrieved 30 May 2015 Sustainable aviation fuel market demand drives new product launches Investable Universe 4 December 2020 Retrieved 12 December 2022 Note Investable Universe gt About Doliente SS et al 10 July 2020 Bio aviation Fuel A Comprehensive Review and Analysis of the Supply Chain Components PDF Frontiers in Energy Research 8 doi 10 3389 fenrg 2020 00110 Developing Sustainable Aviation Fuel SAF IATA Bauen A Howes J Bertuccioli L Chudziak C August 2009 Review of the potential for biofuels in aviation CiteSeerX 10 1 1 170 8750 IATA December 2023 Net zero 2050 sustainable aviation fuels December 2023 www iata org flynetzero Archived from the original on 24 February 2024 Mark Pilling 25 March 2021 How sustainable fuel will help power aviation s green revolution Flight Global Ryckebosch E Drouillon M Vervaeren H 1 May 2011 Techniques for transformation of biogas to biomethane Biomass and Bioenergy 35 5 1633 1645 Bibcode 2011BmBe 35 1633R doi 10 1016 j biombioe 2011 02 033 ISSN 0961 9534 A Detailed Economic Assessment of Anaerobic Digestion Technology and its Suitability to UK Farming and Waste Systems Andersons National Non Food Crops Centre 4 October 2008 NNFCC 08 006 Archived from the original on 4 October 2008 Retrieved 2 January 2023 Yee A 21 September 2018 In Sweden Trash Heats Homes Powers Buses and Fuels Taxi Fleets The New York Times ISSN 0362 4331 Retrieved 14 March 2024 BIOGAS No bull manure can power your farm Farmers Guardian 25 September 2009 12 General OneFile Gale Nagel F 2008 Electricity from wood through the combination of gasification and solid oxide fuel cells PhD thesis Swiss Federal Institute of Technology Zurich Archived from the original on 13 March 2011 a b Biofuel from Algae The Pros and Cons of Pond Scum Thomasnet Archived from the original on 6 April 2020 Retrieved 25 October 2020 Biomass Offshore wind farms seaweed biofuel Renewable Energy Magazine at the heart of clean energy journalism 14 September 2020 Archived from the original on 27 July 2020 Retrieved 16 October 2020 Greenwell HC Laurens LM Shields RJ Lovitt RW Flynn KJ May 2010 Placing microalgae on the biofuels priority list a review of the technological challenges Journal of the Royal Society Interface 7 46 703 726 doi 10 1098 rsif 2009 0322 PMC 2874236 PMID 20031983 Dinh LT Guo Y Mannan MS 2009 Sustainability evaluation of biodiesel production using multicriteria decision making Environmental Progress amp Sustainable Energy 28 1 38 46 Bibcode 2009EPSE 28 38D doi 10 1002 ep 10335 S2CID 111115884 Ajayebi A Gnansounou E Kenthorai Raman J 1 December 2013 Comparative life cycle assessment of biodiesel from algae and jatropha A case study of India Bioresource Technology 150 429 437 Bibcode 2013BiTec 150 429A doi 10 1016 j biortech 2013 09 118 ISSN 0960 8524 PMID 24140355 Yang J Xu M Zhang X Hu Q Sommerfeld M Chen Y January 2011 Life cycle analysis on biodiesel production from microalgae water footprint and nutrients balance PDF Bioresource Technology 102 1 159 165 Bibcode 2011BiTec 102 159Y doi 10 1016 j biortech 2010 07 017 PMID 20675125 Archived from the original PDF on 27 February 2012 Cornell CB 29 March 2008 First Algae Biodiesel Plant Goes Online 1 April 2008 Gas 2 0 Archived from the original on 18 June 2019 Retrieved 10 June 2008 Demirbas AH 2011 Biodiesel from oilgae biofixation of carbon dioxide by microalgae A solution to pollution problems Applied Energy 88 10 3541 3547 Bibcode 2011ApEn 88 3541D doi 10 1016 j apenergy 2010 12 050 hdl 11503 1330 Demirbas AH 2009 Inexpensive oil and fats feedstocks for production of biodiesel Energy Education Science and Technology Part A Energy Science and Research 23 1 13 Rodionova M Poudyal R Tiwari I Voloshin R Zharmukhamedov S Nam H et al March 2017 Biofuel production Challenges and opportunities International Journal of Hydrogen Energy 42 12 8450 8461 doi 10 1016 j ijhydene 2016 11 125 Wesoff E 19 April 2017 Hard Lessons From the Great Algae Biofuel Bubble Archived from the original on 5 July 2017 Retrieved 5 August 2017 a b c Aro EM January 2016 From first generation biofuels to advanced solar biofuels Ambio 45 Supplement 1 S24 S31 Bibcode 2016Ambio 45S 24A doi 10 1007 s13280 015 0730 0 PMC 4678123 PMID 26667057 a b Abdullah B Muhammad SA Shokravi Z Ismail S Kassim KA Mahmood AN et al June 2019 Fourth generation biofuel A review on risks and mitigation strategies Renewable and Sustainable Energy Reviews 107 37 50 doi 10 1016 j rser 2019 02 018 S2CID 116245776 Lu J Sheahan C Fu P 2011 Metabolic engineering of algae for fourth generation biofuels production Energy amp Environmental Science 4 7 2451 doi 10 1039 c0ee00593b ISSN 1754 5692 Xu F Li Y Ge X Yang L Li Y 1 January 2018 Anaerobic digestion of food waste Challenges and opportunities Bioresource Technology 247 1047 1058 doi 10 1016 j biortech 2017 09 020 ISSN 0960 8524 PMID 28965912 Mahmudul HM Rasul MG Akbar D Narayanan R Mofijur M 20 January 2021 A comprehensive review of the recent development and challenges of a solar assisted biodigester system Science of the Total Environment 753 141920 doi 10 1016 j scitotenv 2020 141920 ISSN 0048 9697 PMID 32889316 Kougias PG Angelidaki I 30 April 2018 Biogas and its opportunities A review Frontiers of Environmental Science amp Engineering 12 3 14 doi 10 1007 s11783 018 1037 8 ISSN 2095 221X Zhang C Su H Baeyens J Tan T 1 October 2014 Reviewing the anaerobic digestion of food waste for biogas production Renewable and Sustainable Energy Reviews 38 383 392 doi 10 1016 j rser 2014 05 038 ISSN 1364 0321 Biofuel energy production Our World in Data Retrieved 15 August 2023 Is the biofuel industry approaching a feedstock crunch Analysis IEA Retrieved 13 March 2024 Towards sustainable production and use of resources Assessing Biofuels Archived 2016 05 13 at the Portuguese Web Archive 2009 International Resource Panel United Nations Environment Programme Indonesia s biodiesel drive is leading to deforestation BBC News 8 December 2021 Press corner European Commission European Commission Retrieved 19 April 2024 Biomass Strategy 2023 GOV UK Retrieved 19 April 2024 Food vs fuel Ukraine war sharpens debate on use of crops for energy Financial Times 12 June 2022 Archived from the original on 10 December 2022 Guest view Global hunger fight means no biofuel Reuters 6 June 2022 Cutting biofuels can help avoid global food shock from Ukraine war New Scientist 14 March 2022 Antizar Ladislao B Turrion Gomez JL September 2008 Second generation biofuels and local bioenergy systems Biofuels Bioproducts and Biorefining 2 5 455 469 doi 10 1002 bbb 97 S2CID 84426763 Bryngemark E December 2019 Second generation biofuels and the competition for forest raw materials A partial equilibrium analysis of Sweden Forest Policy and Economics 109 102022 doi 10 1016 j forpol 2019 102022 ISSN 1389 9341 S2CID 212954432 Jacob Lopes E Zepka LQ Severo IA Maroneze MM eds 2022 3rd generation biofuels disruptive technologies to enable commercial production Woodhead Publishing series in energy Cambridge MA Kidlington Woodhead Publishing an imprint of Elsevier ISBN 978 0 323 90971 6 Magazine H Biofuel Made from Algae Isn t the Holy Grail We Expected Hakai Magazine Retrieved 31 March 2024 Palm Oil Exporter Indonesia Concerned by EU s Deforestation Law Jakarta Globe 22 May 2022 EU palm oil use and imports seen plummeting by 2032 Reuters 8 December 2022 Forsberg C January 2009 The Real Path to Green Energy Hybrid Nuclear Renewable Power Bulletin of the Atomic Scientists 65 6 65 71 doi 10 2968 065006007 ISSN 0096 3402 a b Timothy Searchinger et al 29 February 2008 Use of U S Croplands for Biofuels Increases Greenhouse Gases Through Emissions from Land Use Change Science 319 5867 1238 1240 Bibcode 2008Sci 319 1238S doi 10 1126 science 1151861 PMID 18258860 S2CID 52810681 Originally published online in Science Express on 7 February 2008 available here Archived 2009 12 11 at the Wayback Machine a b Michael Wang Zia Haq 14 March 2008 Letter to Science about Searchinger et al article PDF Argonne National Laboratory Archived from the original PDF on 15 February 2013 Retrieved 7 June 2009 The published version on Science Letters is included in Searchinger E Letter responses 2008 08 12 a b Gnansounou et al March 2008 Accounting for indirect land use changes in GHG balances of biofuels Review of current approaches PDF Ecole Polytechnique Federale de Lausanne Retrieved 7 June 2009 Working Paper REF 437 101 Alexander E Farrell 13 February 2008 Better biofuels before more biofuels San Francisco Chronicle Retrieved 7 June 2009 Donald Sawyer 27 May 2008 Climate change biofuels and eco social impacts in the Brazilian Amazon and Cerrado Philosophical Transactions of the Royal Society 363 1498 1747 1752 doi 10 1098 rstb 2007 0030 PMC 2373893 PMID 18267903 Published on line 2008 02 11 Naylor et al November 2007 The Ripple Effect Biofuels Food Security and the Environment Environment Retrieved 7 June 2009 Renton Righelato Dominick V Spracklen 17 August 2007 Carbon Mitigation by Biofuels or by Saving and Restoring Forests Science 317 5840 902 doi 10 1126 science 1141361 PMID 17702929 S2CID 40785300 Sources edit Avril Group ed 2015 A new springtime for the oils and proteins sectors Activity Report 2014 PDF Report Paris Avril p 65 Archived from the original PDF on 26 October 2020 Retrieved 11 August 2022 EurObserv July 2014 Biofuel barometer PDF Report External links edit nbsp Look up biofuel in Wiktionary the free dictionary Biofuels Journal Alternative Fueling Station Locator Archived 14 July 2008 at the Wayback Machine EERE Towards Sustainable Production and Use of Resources Assessing Biofuels by the United Nations Environment Programme October 2009 Biofuels guidance for businesses including permits and licences required on NetRegs gov uk How Much Water Does It Take to Make Electricity Natural gas requires the least water to produce energy some biofuels the most according to a new study International Conference on Biofuels Standards European Union Biofuels Standardization Biofuels from Biomass Technology and Policy Considerations Thorough overview from MIT The Guardian news on biofuels The US DOE Clean Cities Program links to the 87 US Clean Cities coalitions as of 2004 Biofuels Factsheet by the University of Michigan s Center for Sustainable Systems Learn Biofuels Educational Resource for Students Retrieved from https en wikipedia org w index php title Biofuel amp oldid 1222311176, wikipedia, wiki, book, books, library,

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