Biofuel in the United States
The United States produces mainly biodiesel and ethanol fuel, which uses corn as the main feedstock. The US is the world's largest producer of ethanol, having produced nearly 16 billion gallons in 2017 alone. The United States, together with Brazil accounted for 85% of all ethanol prodbruction, with total world production of 27.05 billion gallons. Biodiesel is commercially available in most oilseed-producing states., it was somewhat more expensive than fossil diesel, though it is still commonly produced in relatively small quantities, in comparison to petroleum products and ethanol fuel.
Biofuels are mainly used mixed with fossil fuels. They are also used as additives. The largest biodiesel consumer is the U.S. Army. Most light vehicles on the road today in the US can run on blends of up to 10% ethanol, and motor vehicle manufacturers already produce vehicles designed to run on much higher ethanol blends. The demand for bioethanol fuel in the United States was stimulated by the discovery in the late 90s that methyl tertiary butyl ether, an oxygenate additive in gasoline, was contaminating groundwater. Cellulosic biofuels are under development, to avoid upward pressure on food prices and land use changes that would be expected to result from a major increase in use of food biofuels.
Biofuels are not just limited to liquid fuels. One of the often overlooked uses of biomass in the United States is in the gasification of biomass. There is a small, but growing number of people using woodgas to fuel cars and trucks all across America.
The challenge is to expand the market for biofuels beyond the farm states where they have been most popular to date. Flex-fuel vehicles are assisting in this transition because they allow drivers to choose different fuels based on price and availability.
The growing ethanol and biodiesel industries are providing jobs in plant construction, operations, and maintenance, mostly in rural communities. According to the Renewable Fuels Association, the ethanol industry created almost 154,000 U.S. jobs in 2005 alone, boosting household income by $5.7 billion. It also contributed about $3.5 billion in tax revenues at the local, state, and federal levels. On the other hand, in 2010, the industry received $6.646 billion in federal support, not counting state and local support.
Based upon average U.S. corn yields for the years 2007 through 2012, conversion of the entire US corn crop would yield 34.4 billion gallons of ethanol which is approximately 25% of 2012 finished motor fuel demand.
History
The United States used biofuel in the beginning of the 20th century. For example, models of Ford T ran with ethanol fuel. Then the interest in biofuels declined until the first and second oil crisis, in 1973 and 1979.The Department of Energy established the National Renewable Energy Laboratory in 1974 and started to work in 1977. The NREL publish papers on biofuels. Congress also voted the Energy Policy Act in 1994 and a newer in 2005 to promote renewable fuels.
Congress established regulars under the Energy Policy Act of 2005 intended to encourage the mixing of renewable fuels into our nation's motor vehicle fuel supply. Congress supported the renewable fuels program under the Energy Independence and Security Act of 2007 to contain particular annual volume standards for complete renewable fuel and also for the fixed renewable fuel groups of biomass-based diesel, biofuel, and advanced biofuel. The reassessed statutory requirements also incorporate new criteria for both renewable fuels and for the feedstocks used to produce them, including lifecycle greenhouse gas emission thresholds.
Legislation
Renewable Fuel Standard (RFS1)
The current National Renewable Fuel Standard program was established under the Energy Policy Act of 2005, which amended the Clean Air Act by establishing the first national renewable fuel standard. The U.S. Congress gave the U.S. Environmental Protection Agency the responsibility to coordinate with the U.S. Department of Energy, the U.S. Department of Agriculture, and stakeholders to design and implement this new program.The Renewable Fuel Standard called for of biofuels to be used annually by 2012, expanding the market for biofuels.
The EPA announced that the 2009 Renewable Fuel Standard will require most refiners, importers, and non-oxygenate blenders of gasoline to displace 10.21% of their gasoline with renewable fuels such as ethanol. That requirement aims to ensure that at least of renewable fuels will be sold in 2009, in keeping with the targets established by the Energy Independence and Security Act of 2007. While the RFS requirement is increasing by about 23%—from in 2008 to in 2009—the percentage requirement is increasing by nearly one third, from 7.76% in 2008 to 10.21% in 2009.
The EPA determines that fuel blenders are meeting renewable fuel requirements by examining Renewable Identification Numbers that they submit to the agency.
The 2009 RFS is also pushing up against what is known as the "blend wall". To address the blend wall issue, DOE and others are studying the use of mid-range blends, such as E15 and E20, for use in standard gasoline-burning vehicles. Allowing all gasoline blends to contain up to 20% ethanol would double the potential market for ethanol.
Renewable Fuel Standard (RFS2)
In May 2009, the EPA released proposed revisions to the National Renewable Fuel Standard program. These revisions addressed changes to the Renewable Fuel Standard program as required by EISA. The revised statutory requirements establish new specific volume standards for cellulosic biofuel, biomass-based diesel, advanced biofuel, and total renewable fuel that must be used in transportation fuel each year. The revised statutory requirements also include new definitions and criteria for both renewable fuels and the feedstocks used to produce them, including new greenhouse gas emission thresholds for renewable fuels. The regulatory requirements for RFS will apply to domestic and foreign producers and importers of renewable fuel.Of these modifications, several are significantly notable. First, the volume standard under RFS2 was increased beginning in 2008 from. Thereafter, the required volume continues to increase under RFS2, eventually reaching by 2022.
Volume Standards
Greenhouse gas reduction thresholds
EISA established new renewable fuel categories and eligibility requirements, including setting the first ever mandatory greenhouse gas reduction thresholds for the various categories of fuels. For each renewable fuel pathway, greenhouse gas emissions are evaluated over the full life cycle, including production and transport of the feedstock; land use change; production, distribution, and blending of the renewable fuel; and end use of the renewable fuel. The GHG emissions are then compared to the life cycle emissions of 2005 petroleum baseline fuels displaced by the renewable fuel, such as gasoline or diesel. The life cycle GHG emissions performance reduction thresholds as established by EISA range from 20 to 60 percent reduction depending on the renewable fuel category.| RIN code | Type | % reduction |
| D6 | Conventional biofuel | 20% |
| D5 | Advanced biofuels | 50% |
| D4 | Biomass-derived diesel | 50% |
| D3 | Cellulosic biofuel | 60% |
| D7 | Cellulosic diesel | 60% |
A 2022 study found that land use change emissions resulting from the RFS2 were likely large enough to preclude corn ethanol from complying with the 20% greenhouse gas reductions required of "conventional biofuel" under the EISA.
Renewable fuels
Ethanol fuel
The demand for ethanol fuel in the United States was stimulated by the discovery in the late 1990s that methyl tertiary butyl ether, an oxygenate additive in gasoline, was contaminating groundwater. Due to the risks of widespread and costly litigation, and because MTBE use in gasoline was banned in almost 20 states by 2006, the substitution of MTBE opened a new market for ethanol fuel. This demand shift for ethanol as an oxygenate additive took place at a time when oil prices were already significantly rising. This shift also contributed to an expansion in the use of gasohol E10 and to a sharp increase in the production and sale of E85 flex vehicles since 2002.Low ethanol blends
Most cars on the road today in the U.S. can run on blends of up to 10% ethanol, and motor vehicle manufacturers already produce vehicles designed to run on much higher ethanol blends. Though E10 is mandatory only in 10 states, ethanol blends in the US are available in other states as optional or added on lower percentages as a substitute to MTBE without any labeling, making E blends present in two-thirds of the US gas supply.Flex-fuel vehicles
, DaimlerChrysler, and GM are among the automobile companies that sell "flexible-fuel" cars, trucks, and minivans that can use gasoline and ethanol blends ranging from pure gasoline up to 85% ethanol. By mid-2008, there were approximately seven million E85-compatible vehicles on U.S. roads. However, a 2005 survey found that 68% of American flex-fuel car owners were not aware they owned an E85 flex. This is due to the fact that the exterior of flex and non-flex vehicles look exactly the same; there is no sale price difference between them; the lack of consumer's awareness about E85s; and also the decision of American automakers of not putting any kind of exterior labeling, so buyers can be aware they are getting an E85 vehicle. Since 2006 many new FFV models in the US feature a bright yellow gas cap to remind drivers of the E85 capabilities, and GM is also using badging with the text "Flexfuel/E85 Ethanol" to clearly mark the car as an E85 FFV.File:Flexfuel Chevy Tahoe.jpg|thumb|200px|Promotional E85 Flexfuel Chevy Tahoe.
A major restriction hampering sales of E85 flex vehicles or fuelling with E85, is the limited infrastructure available to sell E85 to the public, as by October 2008 there were only 1,802 gasoline filling stations selling E85 to the public in the entire US, with a great concentration of E85 stations in the Corn Belt states, led by Minnesota with 357 stations, more than any other state, followed by Illinois with 189, Wisconsin with 118, and Missouri with 112. Only seven states do not have E85 available to the public, Alaska, Hawaii, Maine, New Hampshire, New Jersey, Rhode Island, and Vermont. The main constraint for a more rapid expansion of E85 availability is that it requires dedicated storage tanks at filling stations, at an estimated cost of USD 60,000 for each dedicated ethanol tank.
Chrysler, General Motors, and Ford have each pledged to manufacture 50 percent of their entire vehicle line as flexible fuel in model year 2012, if enough fueling infrastructure develops. Regarding energy policy, President-elect Barack Obama pledged during his electoral campaign to significantly reduce oil consumption, with measures that among others include mandating all new vehicles to have FFV capability by the end of 2013.