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89-505: In 2015, Valley Regional Hospital was rated as being in the top 25 of hospitals nationally on a set of composite quality and patient experience measures. Starting 2015, the hospital began using green fuel, specifically 250,000 gallons per year of cellulosic ethanol . This article relating to a hospital in New Hampshire is a stub . You can help Misplaced Pages by expanding it . Cellulosic ethanol Cellulosic ethanol

178-560: A congressional charter under Title 36 of the United States Code . Congress legislated, and President Abraham Lincoln signed, a 1863 Act of Congress establishing the National Academy of Sciences as an independent, trusted government institution created for the purpose of "providing independent, objective advice to the nation on matters related to science and technology [and] to provide scientific advice to

267-480: A 17-member Council, made up of five officers (president, vice president, home secretary, international secretary, and treasurer) and 12 Councilors, all of whom are elected from among the academy membership. Agencies of the United States government fund about 85 percent of the academy's activities. Further funding comes from state governments, private foundations, and industrial organizations. The council has

356-507: A boom in cellulosic ethanol research and pilot plants occurred in the early 2000s. Companies such as Iogen , POET , and Abengoa built refineries that can process biomass and turn it into ethanol, while companies such as DuPont , Diversa , Novozymes , and Dyadic invested in enzyme research. However, most of these plants were canceled or closed in the early 2010s as technical obstacles proved too difficult to overcome. As of 2018, only one cellulosic ethanol plant remained operational. In

445-472: A cellulose substrate into ethanol. One example is Clostridium thermocellum , which uses a complex cellulosome to break down cellulose and synthesize ethanol. However, C. thermocellum also produces other products during cellulose metabolism, including acetate and lactate , in addition to ethanol, lowering the efficiency of the process. Some research efforts are directed to optimizing ethanol production by genetically engineering bacteria that focus on

534-422: A country's dependence on oil imports . Commercial production of cellulosic ethanol, which unlike corn and sugarcane would not compete with food production, would be highly attractive since it would alleviate pressure on these foodcrops. Although its processing costs are higher, the price of cellulose biomass is much cheaper than that of grains or fruits. Moreover, since cellulose is the main component of plants,

623-511: A formal nomination, followed by a vetting period, and culminates in a final ballot at the academy's annual meeting in April each year. Members are affiliated with a specific scientific field in one of six so-called "classes", which include: Physical and Mathematical Sciences; Biological Sciences; Engineering and Applied Sciences; Biomedical Sciences; Behavioral and Social Sciences; and Applied Biological, Agricultural, and Environmental Sciences. Over

712-526: A habitat for upland game, such as pheasants and ducks, and a number of insects. Switchgrass for biofuel production has been considered for use on Conservation Reserve Program (CRP) land, which could increase ecological sustainability and lower the cost of the CRP program. However, CRP rules would have to be modified to allow this economic use of the CRP land. Miscanthus × giganteus is another viable feedstock for cellulosic ethanol production. This species of grass

801-532: A letter signed by 255 Academy members was published in Science magazine , decrying "political assaults" against climate change scientists. This was in response to a civil investigative demand on the University of Virginia (UVA) by Virginia Attorney General Ken Cuccinelli , seeking a broad range of documents from Michael E. Mann , a former UVA professor from 1999 to 2005. Mann, who currently works at

890-406: A lower compression ratio. The main disadvantage of cellulosic ethanol is its high cost and complexity of production, which has been the main impediment to its commercialization. Although the global bioethanol market is sizable (around 110 billion liters in 2019), the vast majority is made from corn or sugarcane , not cellulose. In 2007, the cost of producing ethanol from cellulosic sources

979-625: A nation in Civil War as the Lazzaroni had hoped, nor did it centralize American scientific efforts. However, election to the National Academy did come to be considered "the pinnacle of scientific achievement for Americans" until the establishment of the Nobel Prize at the end of the 19th century. In 1870, the congressional charter was amended to remove the limitation on the number of members. In 2013, astrophysicist Neil deGrasse Tyson

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1068-542: A number of different awards: In 2005, the national science academies of the G8  forum (including the National Academy of Sciences) and science academies of Brazil, China, and India (three of the largest emitters of greenhouse gases in the developing world) signed a statement on the global response to climate change . The statement stresses that the scientific understanding of climate change had become sufficiently clear to justify nations taking prompt action. On May 7, 2010,

1157-472: A one to two order smaller magnitude of efficiency. Therefore, it requires 40 to 100 times more of the enzyme to be present in its production. For each ton of biomass it requires 15-25 kilograms of enzyme. More recent estimates are lower, suggesting 1 kg of enzyme per dry tonne of biomass feedstock. There is also relatively high capital costs associated with the long incubation times for the vessel that perform enzymatic hydrolysis. Altogether, enzymes comprise

1246-614: A pilot plant in 2017 and 2020 in New South Wales as part of efforts to diversify the regional economy away from coal mining. National Academy of Sciences The National Academy of Sciences ( NAS ) is a United States nonprofit, non-governmental organization . NAS is part of the National Academies of Sciences, Engineering, and Medicine , along with the National Academy of Engineering (NAE) and

1335-469: A proposed mandate for 35 billion US gallons (130 × 10 ^  L) of ethanol by 2017. Later that year, the US Department of Energy awarded $ 385 million in grants aimed at jump-starting ethanol production from nontraditional sources like wood chips, switchgrass, and citrus peels. The stages to produce ethanol using a biological approach are: In 2010, a genetically engineered yeast strain

1424-524: A significant obstacle to the dilute acid process is that the hydrolysis is so harsh that toxic degradation products are produced that can interfere with fermentation. BlueFire Renewables uses concentrated acid because it does not produce nearly as many fermentation inhibitors, but must be separated from the sugar stream for recycle [simulated moving bed chromatographic separation, for example] to be commercially attractive. Agricultural Research Service scientists found they can access and ferment almost all of

1513-439: A significant portion of 20-40% for cellulosic ethanol production. A 2016 paper estimates the range at 13-36% of cash costs, with a key factor being how the cellulase enzyme is produced. For cellulase produced offsite, enzyme production amounts to 36% of cash cost. For enzyme produced onsite in a separate plant, the fraction is 29%; for integrated enzyme production, the fraction is 13%. One of the key benefits of integrated production

1602-404: A type of biofuel produced from lignocellulose , a structural material that comprises much of the mass of plants and is composed mainly of cellulose , hemicellulose and lignin . Popular sources of lignocellulose include both agricultural waste products (e.g. corn stover or wood chips ) and grasses like switchgrass and miscanthus species. These raw materials for ethanol production have

1691-423: Is ethanol (ethyl alcohol) produced from cellulose (the stringy fiber of a plant) rather than from the plant's seeds or fruit . It can be produced from grasses , wood , algae , or other plants. It is generally discussed for use as a biofuel . The carbon dioxide that plants absorb as they grow offsets some of the carbon dioxide emitted when ethanol made from them is burned , so cellulosic ethanol fuel has

1780-494: Is a native tallgrass prairie grass. Known for its hardiness and rapid growth, this perennial grows during the warm months to heights of 2–6 feet. Switchgrass can be grown in most parts of the United States, including swamplands, plains, streams, and along the shores & interstate highways . It is self-seeding (no tractor for sowing, only for mowing), resistant to many diseases and pests, & can produce high yields with low applications of fertilizer and other chemicals. It

1869-409: Is accompanied by less soil erosion and improved soil fertility. Additionally, nonfermentable and unconverted solids left after making ethanol can be burned to provide the fuel needed to operate the conversion plant and produce electricity. Energy used to run corn-based ethanol plants is derived from coal and natural gas. The Institute for Local Self-Reliance estimates the cost of cellulosic ethanol from

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1958-468: Is also tolerant to poor soils, flooding, & drought; improves soil quality and prevents erosion due its type of root system. Switchgrass is an approved cover crop for land protected under the federal Conservation Reserve Program (CRP). CRP is a government program that pays producers a fee for not growing crops on land on which crops recently grew. This program reduces soil erosion, enhances water quality, and increases wildlife habitat. CRP land serves as

2047-477: Is an NAS conference facility. The president is the head of the academy, elected by a majority vote of the membership to serve in this position for a term to be determined by the governing Council, not to exceed six years, and may be re-elected for a second term. The academy has had 22 presidents since its foundation. The current president is geophysicist Marcia K. McNutt , the first woman to hold this position. Her term expires on June 30, 2022. The academy gives

2136-513: Is an example of a promising pretreatment that produces no inhibitors. Most pretreatment processes are not effective when applied to feedstocks with high lignin content, such as forest biomass. These require alternative or specialized approaches. Organosolv , SPORL ('sulfite pretreatment to overcome recalcitrance of lignocellulose') and SO2-ethanol-water (AVAP®) processes are the three processes that can achieve over 90% cellulose conversion for forest biomass, especially those of softwood species. SPORL

2225-424: Is characterized by efficient recovery of chemicals. The hydrolysis of cellulose ( cellulolysis ) produces simple sugars that can be fermented into alcohol. There are two major cellulolysis processes: chemical processes using acids, or enzymatic reactions using cellulases . In the traditional methods developed in the 19th century and at the beginning of the 20th century, hydrolysis is performed by attacking

2314-636: Is its ability to ferment five carbon sugars improving the yield of the feed stock. This ability is often found in bacteria based organisms. In the first decade of the 21st century, engineered yeasts have been described efficiently fermenting xylose, and arabinose, and even both together. Yeast cells are especially attractive for cellulosic ethanol processes because they have been used in biotechnology for hundreds of years, are tolerant to high ethanol and inhibitor concentrations and can grow at low pH values to reduce bacterial contamination. Some species of bacteria have been found capable of direct conversion of

2403-492: Is more difficult and more expensive to process into ethanol than corn or sugarcane. The US Department of Energy estimated in 2007 that it costs about $ 2.20 per gallon to produce cellulosic ethanol, which is 2–3 times much as ethanol from corn. Enzymes that destroy plant cell wall tissue cost US$ 0.40 per gallon of ethanol compared to US$ 0.03 for corn. However, cellulosic biomass is cheaper to produce than corn, because it requires fewer inputs, such as energy, fertilizer, herbicide, and

2492-401: Is native to Asia and is a sterile hybrid of Miscanthus sinensis and Miscanthus sacchariflorus . It has high crop yields, is cheap to grow, and thrives in a variety of climates. However, because it is sterile, it also requires vegetative propagation , making it more expensive. It has been suggested that Kudzu may become a valuable source of biomass. Fueled by subsidies and grants,

2581-620: Is that biomass instead of glucose is the enzyme growth medium. Biomass costs less, and it makes the resulting cellulosic ethanol a 100% second-generation biofuel, i.e., it uses no ‘food for fuel’. In general there are two types of feedstocks: forest (woody) Biomass and agricultural biomass . In the US, about 1.4 billion dry tons of biomass can be sustainably produced annually. About 370 million tons or 30% are forest biomass. Forest biomass has higher cellulose and lignin content and lower hemicellulose and ash content than agricultural biomass. Because of

2670-450: Is the high diversity and abundance of cellulose sources; grasses, trees and algae are found in almost every environment on Earth. Even municipal solid waste components like paper could conceivably be made into ethanol. The main current disadvantage of cellulosic ethanol is its high cost of production, which is more complex and requires more steps than corn-based or sugarcane-based ethanol. Cellulosic ethanol received significant attention in

2759-529: Is the most energy efficient (sugar production per unit energy consumption in pretreatment) and robust process for pretreatment of forest biomass with very low production of fermentation inhibitors. Organosolv pulping is particularly effective for hardwoods and offers easy recovery of a hydrophobic lignin product by dilution and precipitation. AVAP® process effectively fractionates all types of lignocellulosics into clean highly digestible cellulose, undegraded hemicellulose sugars, reactive lignin and lignosulfonates, and

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2848-705: The Proceedings of the National Academy of Sciences (PNAS), its scholarly journal. The National Academies Press is the publisher for the National Academies and makes more than 5,000 publications freely available on its website. From 2004 to 2017, the National Academy of Sciences administered the Marian Koshland Science Museum to provide public exhibits and programming related to its policy work. The museum's exhibits focused on climate change and infectious disease . In 2017,

2937-562: The Ivy League , account for nearly 28% of all members ever elected. Those ten are also precisely the only institutions in the entire history of the NAS to have had 100 or more members overall. On the list for living members, only 14 institutions have 50 or more members overall, including the medical school (where it applies). They represent 32% of all living members of the NAS. The National Academy of Sciences maintains multiple buildings around

3026-455: The National Academy of Medicine (NAM). As a national academy , new members of the organization are elected annually by current members, based on their distinguished and continuing achievements in original research. Election to the National Academy is one of the highest honors in the scientific field. Members of the National Academy of Sciences serve pro bono as "advisers to the nation" on science, engineering, and medicine. The group holds

3115-641: The USFS 's Forest Products Laboratory . During World War II, the US again turned to cellulosic ethanol, this time for conversion to butadiene to produce synthetic rubber. The Vulcan Copper and Supply Company was contracted to construct and operate a plant to convert sawdust into ethanol. The plant was based on modifications to the original German Scholler process as developed by the Forest Products Laboratory. This plant achieved an ethanol yield of 50 US gal (190 L) per dry ton, but

3204-422: The 2000s and early 2010s. The United States government in particular funded research into its commercialization and set targets for the proportion of cellulosic ethanol added to vehicle fuel. A large number of new companies specializing in cellulosic ethanol, in addition to many existing companies, invested in pilot-scale production plants . However, the much cheaper manufacturing of grain-based ethanol, along with

3293-579: The District of Columbia decision announced January 25, 2013, voiding a requirement imposed on car and truck fuel producers in the United States by the Environmental Protection Agency requiring addition of cellulosic biofuels to their products. These issues, along with many other difficult production challenges, led George Washington University policy researchers to state that "in the short term, [cellulosic] ethanol cannot meet

3382-529: The Government, investigate, examine, experiment, and report upon any subject of science or art, the actual expense of such investigations, examinations, experiments, and reports to be paid from appropriations which may be made for the purpose, but the Academy shall receive no compensation whatever for any services to the Government of the United States. The National Academies did not solve the problems facing

3471-500: The NAS, NAE, and NAM. Cultural Programs of the National Academy of Sciences hosts exhibitions exploring intersections of art, science, and culture such as Mathemalchemy . The 2012 Presidential Award for Math and Science Teaching ceremony was held here on March 5, 2014. Approximately 150 staff members work at the NAS Building. In June 2012, it reopened to visitors after a major two-year restoration project which restored and improved

3560-716: The National Academy of Sciences – formerly located at 525 E St., N.W. – hosted visits from the public, school field trips, and permanent science exhibits. NAS also maintains conference centers in California and Massachusetts. The Arnold and Mabel Beckman Center is located on 100 Academy Drive in Irvine, California , near the campus of the University of California, Irvine ; it offers a conference center and houses several NAS programs. The J. Erik Jonsson Conference Center, located at 314 Quissett Avenue in Woods Hole, Massachusetts ,

3649-515: The Senate and House approved it, and President Lincoln signed it. Although hailed as a great step forward in government recognition of the role of science in American society, at the time, the National Academy of Sciences created enormous ill-feelings among scientists, whether or not they were named as incorporators. The act states: [T]he Academy shall, whenever called upon by any department of

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3738-652: The United States, the Standard Alcohol Company opened the first cellulosic ethanol production plant in South Carolina in 1910. Later, a second plant was opened in Louisiana. However, both plants were closed after World War I due to economic reasons. The first attempt at commercializing a process for ethanol from wood was done in Germany in 1898. It involved the use of dilute acid to hydrolyze

3827-544: The United States. The National Academy of Sciences Building is located at 2101 Constitution Avenue , in northwest Washington, D.C. ; it sits on the National Mall , adjacent to the Marriner S. Eccles Federal Reserve Board Building and in front of the headquarters of the U.S. State Department . The building has a neoclassical architectural style and was built by architect Bertram Grosvenor Goodhue . The building

3916-524: The ability ad-hoc to delegate certain tasks to committees. For example, the Committee on Animal Nutrition has produced a series of Nutrient requirements of domestic animals reports since at least 1944, each one being initiated by a different sub-committee of experts in the field for example on dairy cattle . The National Academy of Sciences meets annually in Washington, D.C., which is documented in

4005-493: The addition of women to the academy "continues at a dismal trickle"; at that time there were 1,516 male members and 57 female members. The National Academy of Sciences is one of the 135 member organizations of the International Science Council (ISC). Although there is no formal relationship with state and local academies of science, there often is informal dialogue. The National Academy is governed by

4094-554: The advantage of being abundant and diverse and would not compete with food production, unlike the more commonly used corn and cane sugars. However, they also require more processing to make the sugar monomers available to the microorganisms typically used to produce ethanol by fermentation, which drives up the price of cellulos-derived ethanol. Cellulosic ethanol can reduce greenhouse gas emissions by 85% over reformulated gasoline. By contrast, starch ethanol (e.g., from corn), which most frequently uses natural gas to provide energy for

4183-400: The brewery industry to produce ethanol from hexoses (six-carbon sugars). Due to the complex nature of the carbohydrates present in lignocellulosic biomass , a significant amount of xylose and arabinose (five-carbon sugars derived from the hemicellulose portion of the lignocellulose) is also present in the hydrolysate. For example, in the hydrolysate of corn stover , approximately 30% of

4272-505: The building's historic spaces, increased accessibility, and brought the building's aging infrastructure and facilities up to date. More than 1,000 National Academies staff members work at The Keck Center of the National Academies at 500 Fifth Street in northwest Washington, D.C. The Keck Center provides meeting space and houses the National Academies Press Bookstore. The Marian Koshland Science Museum of

4361-464: The cellulose from the lignin seal and its crystalline structure so as to render it accessible for a subsequent hydrolysis step. By far, most pretreatments are done through physical or chemical means. To achieve higher efficiency, both physical and chemical pretreatments are required. Physical pretreatment involves reducing biomass particle size by mechanical processing methods such as milling or extrusion . Chemical pretreatment partially depolymerizes

4450-421: The cellulose to glucose, and was able to produce 7.6 liters of ethanol per 100 kg of wood waste (18 US gal (68 L) per ton). The Germans soon developed an industrial process optimized for yields of around 50 US gallons (190 L) per ton of biomass. This process soon found its way to the US, culminating in two commercial plants operating in the southeast during World War I. These plants used what

4539-431: The cellulose with an acid. Dilute acid may be used under high heat and high pressure, or more concentrated acid can be used at lower temperatures and atmospheric pressure. A decrystallized cellulosic mixture of acid and sugars reacts in the presence of water to complete individual sugar molecules (hydrolysis). The product from this hydrolysis is then neutralized and yeast fermentation is used to produce ethanol. As mentioned,

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4628-496: The current oil imports into the United States. Paper, cardboard, and packaging comprise around 17% of global household waste; although some of this is recycled. As these products contain cellulose, they are transformable into cellulosic ethanol, which would avoid the production of methane , a potent greenhouse gas, during decomposition. The main overall drawback of ethanol fuel is its lower fuel economy compared to gasoline when using ethanol in an engine designed for gasoline with

4717-501: The difficulties and low ethanol yield in fermenting pretreatment hydrolysate, especially those with very high 5 carbon hemicellulose sugars such as xylose, forest biomass has significant advantages over agricultural biomass. Forest biomass also has high density which significantly reduces transportation cost. It can be harvested year around which eliminates long-term storage. The close to zero ash content of forest biomass significantly reduces dead load in transportation and processing. To meet

4806-560: The early work on acid hydrolysis of wood at the USFS 's Forest Products Laboratory . In 2009, the Forest Products Laboratory together with the University of Wisconsin–Madison developed a sulfite pretreatment to overcome the recalcitrance of lignocellulose for robust enzymatic hydrolysis of wood cellulose. In his 2007 State of the Union Address on January 23, 2007, US President George W. Bush announced

4895-430: The energy security and environmental goals of a gasoline alternative." The French chemist, Henri Braconnot , was the first to discover that cellulose could be hydrolyzed into sugars by treatment with sulfuric acid in 1819. The hydrolyzed sugar could then be processed to form ethanol through fermentation. The first commercialized ethanol production began in Germany in 1898, where acid was used to hydrolyze cellulose. In

4984-469: The entire history of the NAS, Harvard University is associated with the most members (331) overall, while the University of California at Berkeley is associated with the most members (255) without including the medical school. E.g. of the topmost schools, UC Berkeley/MIT/Princeton/Caltech do not have medical schools, while Harvard/Stanford do. The top ten institutions, two of which are from the University of California System and another four of which are in

5073-794: The ethanol-producing pathway. The gasification process does not rely on chemical decomposition of the cellulose chain (cellulolysis). Instead of breaking the cellulose into sugar molecules, the carbon in the raw material is converted into synthesis gas , using what amounts to partial combustion. The carbon monoxide, carbon dioxide and hydrogen may then be fed into a special kind of fermenter . Instead of sugar fermentation with yeast, this process uses Clostridium ljungdahlii bacteria. This microorganism will ingest carbon monoxide, carbon dioxide and hydrogen and produce ethanol and water. The process can thus be broken into three steps: A 2002 study has found another Clostridium bacterium that seems to be twice as efficient in making ethanol from carbon monoxide as

5162-782: The first generation of commercial plants will be in the $ 1.90–$ 2.25 per gallon range, excluding incentives. This compares to the current cost of $ 1.20–$ 1.50 per gallon for ethanol from corn and the current retail price of over $ 4.00 per gallon for regular gasoline (which is subsidized and taxed). Cellulases and hemicellulases used in the production of cellulosic ethanol are more expensive compared to their first generation counterparts. Enzymes required for maize grain ethanol production cost 2.64-5.28 US dollars per cubic meter of ethanol produced. Enzymes for cellulosic ethanol production are projected to cost 79.25 US dollars, meaning they are 20-40 times more expensive. The cost differences are attributed to quantity required. The cellulase family of enzymes have

5251-399: The government 'whenever called upon' by any government department", an objective that promulgated the academy with the broad and enduring purpose of enriching and providing resources to any part of the federal government—rather than as a tool of one branch, or executive agencies, which adds a risk or propensity of becoming the tool of one part of the government. The goal was somewhat unusual at

5340-692: The later 2010s, various companies occasionally attempted smaller-scale efforts at commercializing cellulosic ethanol, although such ventures generally remain at experimental scales and often dependent on subsidies. The companies Granbio, Raízen and the Centro de Tecnologia Canavieira each run a pilot-scale facility operate in Brazil, which together produce around 30 million liters in 2019. Iogen , which started as an enzyme maker in 1991 and re-oriented itself to focus primarily on cellulosic ethanol in 2013, owns many patents for cellulosic ethanol production and provided

5429-446: The lignocellulose so enzymes can access the cellulose for microbial reactions. Chemical pretreatment techniques include acid hydrolysis , steam explosion , ammonia fiber expansion, organosolv, sulfite pretreatment , SO2-ethanol-water fractionation, alkaline wet oxidation and ozone pretreatment. Besides effective cellulose liberation, an ideal pretreatment has to minimize the formation of degradation products because they can inhibit

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5518-401: The low price of oil in the 2010s, meant that cellulosic ethanol was not competitive with these established fuels. As a result, most of the new refineries were closed by the mid-2010s and many of the newly founded companies became insolvent. A few still exist, but are mainly used for demonstration or research purposes; as of 2021, none produces cellulosic ethanol at scale. Cellulosic ethanol is

5607-413: The main product of cellulose hydrolyzate, to ethanol is an already established and efficient technique. However, conversion of xylose, the pentose sugar of hemicellulose hydrolyzate, is a limiting factor, especially in the presence of glucose. Moreover, it cannot be disregarded as hemicellulose will increase the efficiency and cost-effectiveness of cellulosic ethanol production. Sakamoto (2012) et al. show

5696-469: The museum closed and made way for a new science outreach program called LabX. The Act of Incorporation, signed by President Abraham Lincoln on March 3, 1863, created the National Academy of Sciences and named 50 charter members. Many of the original NAS members came from the so-called " Scientific Lazzaroni ", an informal network of mostly physical scientists working in the vicinity of Cambridge, Massachusetts ( c.  1850 ). In 1863,

5785-878: The needs for biodiversity, forest biomass will be an important biomass feedstock supply mix in the future biobased economy. However, forest biomass is much more recalcitrant than agricultural biomass. In 2009, the USDA Forest Products Laboratory together with the University of Wisconsin–Madison developed efficient technologies that can overcome the strong recalcitrance of forest (woody) biomass including those of softwood species that have low xylan content. Short-rotation intensive culture or tree farming can offer an almost unlimited opportunity for forest biomass production. Woodchips from slashes and tree tops and saw dust from saw mills, and waste paper pulp are forest biomass feedstocks for cellulosic ethanol production. Switchgrass ( Panicum virgatum )

5874-730: The net energy output is several times higher than that of corn-based ethanol. The potential raw material is also plentiful. Around 44% of household waste generated worldwide consists of food and greens. An estimated 323 million tons of cellulose-containing raw materials which could be used to create ethanol are thrown away each year in US alone. This includes 36.8 million dry tons of urban wood wastes, 90.5 million dry tons of primary mill residues, 45 million dry tons of forest residues, and 150.7 million dry tons of corn stover and wheat straw. Moreover, even land marginal for agriculture could be planted with cellulose-producing crops, such as switchgrass, resulting in enough production to substitute for all

5963-665: The one mentioned above. Alternatively, the synthesis gas from gasification may be fed to a catalytic reactor where it is used to produce ethanol and other higher alcohols through a thermochemical process. This process can also generate other types of liquid fuels, an alternative concept successfully demonstrated by the Montreal-based company Enerkem at their facility in Westbury, Quebec. Studies are intensively conducted to develop economic methods to convert both cellulose and hemicellulose to ethanol. Fermentation of glucose,

6052-507: The organizers enlisted the support of Alexander Dallas Bache , and also Charles Henry Davis , a professional astronomer who had been recently recalled from the Navy to Washington to head the Bureau of Navigation . They also elicited support from Swiss-American geologist Louis Agassiz and American mathematician Peirce , who together planned the steps whereby the National Academy of Sciences

6141-672: The potential of genetic engineering microbes to express hemicellulase enzymes. The researchers created a recombinant Saccharomyces cerevisiae strain that was able to: The strain was able to convert rice straw hydrolyzate to ethanol, which contains hemicellulosic components. Moreover, it was able to produce 2.5x more ethanol than the control strain, showing the highly effective process of cell surface-engineering to produce ethanol. Ethanol burns more cleanly and more efficiently than gasoline. Because plants consume carbon dioxide as they grow, bioethanol has an overall lower carbon footprint than fossil fuels. Substituting ethanol for oil can also reduce

6230-475: The potential to have a lower carbon footprint than fossil fuels . Interest in cellulosic ethanol is driven by its potential to replace ethanol made from corn or sugarcane . Since these plants are also used for food products, diverting them for ethanol production can cause food prices to rise; cellulose-based sources, on the other hand, generally do not compete with food, since the fibrous parts of plants are mostly inedible to humans. Another potential advantage

6319-421: The process, may not reduce greenhouse gas emissions at all depending on how the starch-based feedstock is produced. According to the National Academy of Sciences in 2011, there is no commercially viable bio-refinery in existence to convert lignocellulosic biomass to fuel. Absence of production of cellulosic ethanol in the quantities required by the regulation was the basis of a United States Court of Appeals for

6408-446: The production of crop commodities. Of the United States' 2.26 billion acres (9.1 million km ) of unsubmerged land, 33% are forestland, 26% pastureland and grassland, and 20% crop land. A study by the U.S. Departments of Energy and Agriculture in 2005 suggested that 1.3 billion dry tons of biomass is theoretically available for ethanol use while maintaining an acceptable impact on forestry, agriculture. Currently, cellulose

6497-497: The remaining sugars in wheat straw. The sugars are located in the plant's cell walls, which are notoriously difficult to break down. To access these sugars, scientists pretreated the wheat straw with alkaline peroxide, and then used specialized enzymes to break down the cell walls. This method produced 93 US gallons (350 L) of ethanol per ton of wheat straw. Cellulose chains can be broken into glucose molecules by cellulase enzymes . This reaction occurs at body temperature in

6586-488: The second President of NAS. Agassiz, Davis, Peirce, Benjamin Gould and Senator Wilson met at Bache's house and "hurriedly wrote the bill incorporating the Academy, including in it the name of fifty incorporators". During the last hours of the session, when the Senate was immersed in the rush of last-minute business before its adjournment, Senator Wilson introduced the bill. Without examining it or debating its provisions, both

6675-784: The stomachs of ruminants such as cattle and sheep, where the enzymes are produced by microbes. This process uses several enzymes at various stages of this conversion. Using a similar enzymatic system, lignocellulosic materials can be enzymatically hydrolyzed at a relatively mild condition (50 °C and pH 5), thus enabling effective cellulose breakdown without the formation of byproducts that would otherwise inhibit enzyme activity. All major pretreatment methods, including dilute acid, require an enzymatic hydrolysis step to achieve high sugar yield for ethanol fermentation. Fungal enzymes can be used to hydrolyze cellulose. The raw material (often wood or straw) still has to be pre-treated to make it amenable to hydrolysis. In 2005, Iogen Corporation announced it

6764-406: The subsequent hydrolysis and fermentation steps. The presence of inhibitors further complicates and increases the cost of ethanol production due to required detoxification steps. For instance, even though acid hydrolysis is probably the oldest and most-studied pretreatment technique, it produces several potent inhibitors including furfural and hydroxymethylfurfural . Ammonia Fiber Expansion (AFEX)

6853-558: The technology for the Raízen plant. Other companies developing cellulosic ethanol technology as of 2021 are Inbicon (Denmark); companies operating or planning pilot production plants include New Energy Blue (US), Sekab (Sweden) and Clariant (in Romania). Abengoa, a Spanish company with cellulosic ethanol assets, became insolvent in 2021. The Australian Renewable Energy Agency , along with state and local governments, partially funded

6942-485: The time, and also different than other knowledge based entities serving a branch of government, such as the Library of Congress. The academy receives no compensation from the government for its services. As of 2024 , the National Academy of Sciences includes 2,687 NAS members and 531 international members . It employed about 1,100 staff in 2005. Some 190 members have won a Nobel Prize. By its own admission in 1989,

7031-648: The total fermentable sugars is xylose. As a result, the ability of the fermenting microorganisms to use the whole range of sugars available from the hydrolysate is vital to increase the economic competitiveness of cellulosic ethanol and potentially biobased proteins. At the turn of the millenium, metabolic engineering for microorganisms used in fuel ethanol production showed significant progress. Besides Saccharomyces cerevisiae , microorganisms such as Zymomonas mobilis and Escherichia coli have been targeted through metabolic engineering for cellulosic ethanol production. An attraction towards alternative fermentation organism

7120-500: The whole plant can be harvested, rather than just the fruit or seeds. This results in much better yields; for instance, switchgrass yields twice as much ethanol per acre as corn. Biomass materials for cellulose production require fewer inputs, such as fertilizer, herbicides, and their extensive roots improve soil quality , reduce erosion, and increase nutrient capture. The overall carbon footprint and global warming potential of cellulosic ethanol are considerably lower (see chart) and

7209-783: Was asked to write a speech for the 150th anniversary of the Gettysburg Address in which he made the point that one of Lincoln's greatest legacies was establishing the National Academy of Sciences in that same year, which had the long-term effect of "setting our Nation on a course of scientifically enlightened governance, without which we all may perish from this Earth". The academy currently (as of late-2024) has 6892 members, including international ones, both past and present. 3218 of them are living. Existing members elect new members for life. Up to 120 members are elected every year while up to 30 foreign citizens may be elected as international members annually. The election process begins with

7298-512: Was called "the American Process" — a one-stage dilute sulfuric acid hydrolysis. Though the yields were half that of the original German process (25 US gallons (95 L) of ethanol per ton versus 50), the throughput of the American process was much higher. A drop in lumber production forced the plants to close shortly after the end of World War I. In the meantime, a small but steady amount of research on dilute acid hydrolysis continued at

7387-469: Was dedicated in 1924 and is listed on the National Register of Historic Places . Goodhue engaged a team of artists and architectural sculptors including Albert Herter , Lee Lawrie , and Hildreth Meière to design interior embellishments celebrating the history and significance of science. The building is used for lectures, symposia, exhibitions, and concerts, in addition to annual meetings of

7476-418: Was developed to produce its own cellulose-digesting enzymes. Assuming this technology can be scaled to industrial levels, it would eliminate one or more steps of cellulolysis, reducing both the time required and costs of production. Although lignocellulose is the most abundant plant material resource, its usability is curtailed by its rigid structure. As a result, an effective pretreatment is needed to liberate

7565-743: Was developing a process using the fungus Trichoderma reesei to secrete "specially engineered enzymes" for an enzymatic hydrolysis process. Another Canadian company, SunOpta, uses steam explosion pretreatment, providing its technology to Verenium (formerly Celunol Corporation)'s facility in Jennings, Louisiana , Abengoa's facility in Salamanca, Spain , and a China Resources Alcohol Corporation in Zhaodong . The CRAC production facility uses corn stover as raw material. Traditionally, baker's yeast ( Saccharomyces cerevisiae ), has long been used in

7654-463: Was estimated ca. USD 2.65 per gallon (€0.58 per liter), which is around 2–3 times more expensive than ethanol made from corn. However, the cellulosic ethanol market remains relatively small and reliant on government subsidies. The US government originally set cellulosic ethanol targets gradually ramping up from 1 billion liters in 2011 to 60 billion liters in 2022. However, these annual goals have almost always been waived after it became clear there

7743-430: Was no chance of meeting them. Most of the plants to produce cellulosic ethanol were canceled or abandoned in the early 2010s. Plants built or financed by DuPont , General Motors and BP , among many others, were closed or sold. As of 2018, only one major plant remains in the US. In order for it to be grown on a large-scale production, cellulose biomass must compete with existing uses of agricultural land, mainly for

7832-407: Was still not profitable and was closed after the war. With the rapid development of enzyme technologies in the last two decades, the acid hydrolysis process has gradually been replaced by enzymatic hydrolysis. Chemical pretreatment of the feedstock is required to hydrolyze (separate) hemicellulose, so it can be more effectively converted into sugars. The dilute acid pretreatment is developed based on

7921-645: Was to be established. Senator Henry Wilson of Massachusetts was to name Agassiz to the Board of Regents of the Smithsonian Institution . Agassiz was to come to Washington, D.C., at the government's expense to plan the organization with the others. This bypassed Joseph Henry , who was reluctant to have a bill for such an academy presented to Congress . This was in the belief that such a resolution would be "opposed as something at variance with our democratic institutions". Nevertheless, Henry soon became

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