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Switchgrass As Jet Fuel For Navy Fighters?
Switchgrass is on the forefront of biomass technology and it could be converted into jet fuel to power Navy planes and more. The National Renewable Energy Laboratory (NREL), run by the Energy Department, is looking into ways that switchgrass could be used to fuel jets. To achieve this goal, the group has partnered with the U.S. Navy, Cobalt Technologies, and the Show Me Energy Cooperative. Producing jet fuel from biomass like switchgrass is not new. However, before jets start flying on fuel made from the grass, production would have to be both affordable and available in quantities large enough to make economic sense. “This can be an important step in the efforts to continue to displace petroleum by using biomass resources. We’re converting biomass into sugars for subsequent conversion to butanol and then to JP5 jet fuel,” Dan Schell, NREL manager for bioprocess integration research and development, said. The Department of Energy is funding four separate projects to find a renewable source of biomass that could be turned into fuel to power both land vehicles and airplanes. Switchgrass is a wild grass that grows in all latitudes of the United States and Mexico, but is found primarily in the prairies. If this wild grass could be successfully used for the production of jet fuel in the large-enough quantities, it would provide a green alternative to fossil fuels, and would not require the use of a food stock like corn. Producing jet fuel from switchgrass would produce 95 percent less greenhouse gases than refining fossil fuels. The grass is collected by the Show Me Energy Cooperative, and then converted into sugars at the NREL through the use of enzymes, after pre-treating with a weak acid. The sugars are then fed into fermenters built by Cobalt Technologies with a capacity of nearly 2,400 gallons. There, they are converted into butyl alcohol (butanol) through the action of microorganisms. Using Navy know-how and catalysts, the alcohol is converted into jet fuel back at NREL. Switchgrass grows throughout Kentucky, where it is also being studied for use as an alternative fuel, if only as biomass to be directly burned. There, researchers from the University of Kentucky College of Agriculture have had some success in using the grass to produce green energy. “We learned a whole lot and found some useful applications for the forage until a consistent biomass market develops,” Ray Smith, University of Kentucky extension forage specialist, said. Interest in the grass from the Navy could be the market for which Smith is looking. If tests are successful, the Departments of Defense and Agriculture will assist companies who wish to produce the greener fuel. Continue reading
Biofuels Will Play Integral Role In California’s Energy Future, Says New EBI Study
Biofuels developed from plant biomass and purpose-grown crops can substantially move California toward its ambitious energy goals, a new report says, but only through the wise allocation of feedstocks and the success of energy efficiency measures throughout the state. That’s the conclusion of “California Energy Future: the Potential for Biofuels,” a report of the California Council on Science and Technology (CCST) co-authored by Energy Biosciences Institute scientists Heather Youngs and Chris Somerville. The study is one of seven produced by the CCST’s California’s Energy Future Committee, which was tasked with understanding how the state can meet aggressive reductions in greenhouse gas (GHG) emissions required by California policy by 2050. The biofuels paper, according to lead author Youngs, a Senior Fellow at the EBI, addressed six scenarios of varied supply and demand options. They illustrate that the degree to which biofuels may help California meet its emissions goals depends upon how future demand for fuels rises or falls and what technologies are developed. Other factors include energy crop availability, investment decisions, public acceptance, and competing demands for renewable energy resources. “The concerns regarding large-scale use of biomass for energy in California are largely a matter of sustainable resource management,” Youngs said. “Judicious use of feedstocks will be required to obviate long-term sustainability concerns and maximize efficient resource management.” The researchers concluded that next-generation biofuels can reduce greenhouse gas emissions of transportation to meet the target GHG reduction goals of the state, but deep replacement of fossil fuels through implementation of low-carbon lignocellulosic ethanol and advanced biomass-derived hydrocarbons (drop-in fuels), and reduction in demand, are required. The challenge for California lies in landmark State Executive Order S-03-05, signed by Arnold Schwarzenegger in 2005. The target: reduce greenhouse gases (GHGs) more than 80 percent from 1990 levels by 2050. The California Legislature has also enacted legislation to encourage low-carbon technologies. Assembly Bill 32, The Global Warming Solutions Act of 2006, put a 2020 GHG target officially on the books. It also paved the way for the Renewable Portfolio Standard that requires 33 percent renewable electricity by 2020, and for adoption of California’s landmark 2009 Low Carbon Fuel Standard. The CCST’s first report in its California Energy Future series summarized the conclusions of a two-year study — in order to reach those goals, a little bit of everything will be required. This includes increased efficiency through reduced demand, shifts to electrification, decarbonized electricity production, and decarbonized liquid and gaseous fuels. Subsequent reports reveal the details, delving into nuclear power, transportation and building efficiency, electricity from renewable sources, and advanced technologies. One key finding of the Committee was that low-carbon fuels are absolutely required to reach the GHG reduction goals. Even with electrification of some vehicles, liquid fuels will still be required for aviation, marine and heavy-duty transportation. “Substantial amounts of low-carbon biofuels would be required even with optimistic efficiency, electrification, and implementation of other renewable energy sources,” the authors state. California has a policy goal of producing 75 percent of its biofuels from in-state resources. Biofuels can be produced using agricultural wastes, forest thinnings and harvest residues, municipal wastes, and purpose-grown energy crops such as perennial grasses and short rotation woody crops. According to the report, this could be difficult. The state could produce 40-120 million tons of biomass or 3 to 10 billion gallons of fuel each year, meeting up to 60 percent of the 2050 demand in the most optimistic case. Success will depend upon overcoming a number of economic, social and sustainability barriers, Youngs said. “Biofuels could reasonably be imported from other states or countries like Brazil,” she noted. “While imported biomass could supply in-state biorefineries to meet the 75 percent goal, this solution would be more costly than the import of biofuels themselves to meet the GHG reduction goals. Decisions regarding biomass use and biofuel import will greatly affect the ability of the state to meet its policy goals.” The authors expressed confidence that future technologies could be deployed to produce a new generation of low-carbon biofuels, like cellulosic ethanol and drop-in biofuels, to meet the demand by 2050. They also urged the proper choice of species and production criteria for feedstocks and fuel conversion technologies by region in the state. This includes development of arid-tolerant feedstocks, water-minimizing conversion technologies, use of grasses that sequester soil carbon and recycle nutrients, and use of plants that can tolerate poor soils and do not compete with food or feed production. All of these issues are being studied at the EBI in Berkeley and Illinois. Source: University of California – Berkeley Continue reading
Explainer: How Much Carbon Can The World’s Forests Absorb?
11 June 2013, 5.35am BST Explainer: how much carbon can the world’s forests absorb? AUTHOR Peter Reich Scientific advisor, Hawkesbury Institute of the Environment at University of Western Sydney DISCLOSURE STATEMENT Peter Reich does not work for, consult to, own shares in or receive funding from any company or organisation that would benefit from this article, and has no relevant affiliations. Provides funding as a Member of The Conversation. uws.edu.au If deforestation is cut down, the world’s forests could act as a large net sink for carbon emissions. Flickr/sobriquet.net You are walking through the bush when you see an enormous tree trunk, tens of metres long, lying across the forest floor. Imagine you and several dozen friends lifting it by hand. Now you’ve literally grasped the significance of trees and forests when it comes to carbon sequestration – trees are heavy, and carbon accounts for almost half their dry weight, or biomass. The world’s forests are a net carbon “sink”. Each year they remove more carbon from the atmosphere by photosynthesis than they return via their own respiration, decomposition of dead roots, trunks and leaves, and by forest fires. That is how the growth and re-growth of forests around the world has slowed climate change in the past century. It has been estimated that between one-third and one-fourth of the total carbon dioxide (CO 2 ) emissions from burning coal, gas and petrol has been turned into wood and other plant parts through this process. Without that incredible ecosystem service, climate change would be much more extreme today than it already is. Despite advances in satellite remote sensing and ground inventories, our estimate of the area covered by forests globally is surprisingly shaky. We are unsure how much the trunks of all those trees weigh, nor can we know for certain the weight of their roots. It is even harder to figure out how much the total global forest biomass grows from one year to the next – a key figure that tells us how much of our annual CO 2 pollution has been scrubbed out of the air by forests. Forest ecologists like a challenge however, and there have been several attempts at estimating the forest carbon “sink”. Perhaps the most internationally comprehensive approach was an assessment of forest carbon stocks and fluxes across the globe between 1990 and 2007. They assessed the carbon content of live biomass, dead wood, litter, oil organic matter and harvested wood products in tropical, temperate and boreal forests, and examined how these stocks changed over roughly two decades. According to this analysis, intact forests and those re-growing after disturbance (like harvesting or windthrow ) sequestered around 4 billion tonnes of carbon per year over the measurement period — equivalent to almost 60% of emissions from fossil fuel burning and cement production combined. This news is not as good as it seems. During the time measured, tropical deforestation resulted in the release of almost 3 billion tonnes per year. Thus, globally, the net forest carbon sink amounted to just 1.1 billion tonnes per year or one-seventh of average emissions from fossil fuel burning and cement production over the period measured. These numbers suggest that forests, and tropical forests in particular, could play a key role in slowing the rise of atmospheric CO 2 in the decades to come. In the tropics, growth and re-growth of forests generated a colossal carbon sink of 2.8 billion tonnes of carbon per year. This largely, but not entirely, counterbalanced the equally colossal carbon emissions associated with deforestation of other tropical forests. As a result, the tropics served as a relatively small net source of carbon to the atmosphere since 1990. If deforestation continues unabated, and droughts and forest fires become more common, as is expected, then tropical forests could become a large net source of carbon to the atmosphere, heating up the pace of climate change. Disturbances to temperate and boreal forests from climate change-induced droughts, wildfires and windstorms could make the situation even worse. Conversely, if deforestation was to slow in comparison to continued growth of recovering and intact forests, tropical forests could serve as a large net sink of carbon in the future and make the United Nation’s Reducing Emissions from Deforestation and Forest Degradation ( REDD ) programme a meaningful contributor to offsetting emissions. Our best estimates of global forest carbon sinks and sources demonstrate the ongoing importance of forests to the global carbon cycle. Unfortunately, however, they do not provide a road map to the future. If forest “scrubbing of CO 2 ” declines while release of CO 2 remains stable or grows, the “braking” effect of the world’s forests on the pace of climate change will grow weaker, perhaps disappearing entirely. That would be truly bad news for the global climate and those who depend on it. And unfortunately, that is not just a lot of hot air. Continue reading
