miércoles, 22 de febrero de 2012

The Biofuels Pipedream

By Richard Matthews

First generation biofuels have been widely criticized, but even second, third and fourth generation biofuels have uncertain technical, economic and environmental viability. A full assessment of the environmental costs of biofuels reveals that the vast majority do not make sense. For biofuels to be a truly feasible alternative to oil, life cycle analysis must take into account not only CO2, but all the associated environmental impacts. The total environmental impacts of biofuel go far beyond the GHGs released by combustion, they must include a host of factors including the impacts they have on biodiversity.

Many are counting on biofuels to contribute substantially to addressing future energy demands. The EU has proposed that 10 percent of all fuel used in transport should come from biofuels by 2020 and the emerging global market is expected to be worth hundreds of billions of dollars a year in the next couple of decades.

The research shows that biofuels are increasingly in demand. In a 2011 report titled Biofuels Markets and Technologies, Pike Research estimates that production of biofuels will increase from $82.7 billion in 2011 to $185.3 billion by 2021. The report goes on to predict that supply will not be able to keep up with demand.

On January 18th, 2012, BP released Energy Outlook 2030, its official corporate view of the future of energy. At the release event in London, BP’s CEO Bob Dudley outlined what he called the “great potential” of biofuels, but Dudley added, “the world needs to focus on biofuels that do not compete with the food chain and are produced in a sustainable way.”

First Generation

First-generation biofuels rely on food crops (e.g.: corn, soy, palm and sugarcane), which have readily accessible sugars, starches and oils. First generation biofuels have been based almost exclusively on conventional fermentation or esterification processes. The problems with first-generation biofuels include net energy losses, GHG emissions, increased food prices and even mass starvation. Further, the increased production of ethanol results in deforestation and more carbon dioxide, a large water footprint, and negatively impacted water quality. It is clear that first generation biofuels are a losing proposition environmentally and economically.
When everything is factored into the equation, using biofuels made from feedstocks like corn, sugar cane and soy may have a greater environmental impact than burning fossil fuels. As summarized in Michael Grunwald’s article The Clean Energy Scam, “ethanol increases global warming, destroys forests, and inflates food prices”.

Second Generation

Second generation biofuels like cellulosic ethanol are not yet commercially available, but believers contend they may significantly alter the energy equation. Second-generation biofuels use non-food feed stock like cellulosic biomass (e.g. grasses, reeds and agricultural residue such as corn stalks). The processing of cellulosic biomass uses enzymes to breakdown the feedstock’s cellulose into sugar and it is then fermented. Alternatively, a thermo-chemical approach gasifies the biomass and then liquefies it in a process known as “biomass-to-liquid.”

Early in 2012, the Advanced Biofuels Association claimed “cellulosic ethanol and advanced biofuels industry is on the cusp of a major increase in scale that will prove critics of the effort to increase biofuels production in the US wrong.” In a recent interview, BP Biofuels North America President Sue Ellerbusch claimed that biofuel manufacturers are “right on the cusp of told you so.” Ellerbusch claims that BP is making sufficient progress that “over time we’ll have an industry that can compete head-on with fossil fuels.”
Research presented by Jeanette Whitaker of the Centre for Ecology and Hydrology in Lancaster, UK, finds that second generation biofuels hold substantially more promise than ethanol made from food-based feedstocks.
In 2009, scientists touted bio char as a potential source of biofuel. Early lab results were promising, suggesting that biochar would lead to less carbon in the atmosphere while also improving crops and soil fertility.
Also in 2009, North Carolina State University researchers Dr. Anne Stomp and Dr. Jay Cheng indicated that they believe duckweed was the key to better ethanol production. Using wastewater for growth, duckweed can create ethanol both faster and cheaper than corn-based ethanol.
Another possible feedstock for the production of biofuel is grass. In 2010, the Carbon Trust started working with the University of York to research how they could use microwave technology to turn garden and wood waste into biofuel. This new biofuel reportedly has a carbon footprint that could save “95 per cent of carbon compared to fossil fuels”.

Early in 2012, researchers indicated that camelina may be the best feedstock for biofuel. Camelina is a low-cost feedstock that has high energy, is non-food, uses marginal land and requires no irrigation. Boeing is already using biofuel derived from camelina for some of its planes.

Also in 2012, a company called DSM announced that it has developed yeast and enzyme solutions that increase biomass conversion rates and make the technology commercially viable.

However, there is a dark lining to these silver clouds. The United Nations has indicated that some of the non-food crops used for the creation of the fuel risk billions of dollars in damages to general agriculture. They cite a scientific report which warns that should invasive species spread, potential damages could easily reach $1.4 trillion annually.

Third Generation

Rather than improving the fuel-making process, third-generation biofuels seek to improve the feedstock. The most viable third-generation biofuels are largely based on fuels extracted from algae cultivated in water. Profitable biodiesel production derived from algae are not expected until at least 2016, but by some estimates, they could account for a third of biofuel production as early as 2022.
Algae may be able to reduce greenhouse gas emissions and serve as a feedstock for biodiesel production. Algae consume carbon dioxide (CO2) for normal growth during photosynthesis, making it a promising sink for carbon dioxide from power, chemical and fermentation projects.

Some reports indicate that algae based fuel can represent up to 30 times more energy per acre than more common crops. While others suggest the yields of oil from algae are 10-100 times more than competing energy crops.

Some strains of algae can produce 50% of their weight of oil, which is far better than rapeseed (which might yield a tonne of biodiesel per hectare), or palm oil (8 tonnes per hectare). Some estimate that as much as 40 – 90 tonnes per hectare is possible from algae. Algae grown in ponds can in principle be placed anywhere and there is no need to use arable land for them. Some algae grow well in salt-water, which conserves freshwater, whereas growing crops requires enormous quantities of freshwater.

Growing algae could become cost-effective if it is combined with environmental clean-up strategies like sewage wastewater treatment and reducing CO2 emissions from smokestacks of fossil-fuelled power stations or cement factories.
Algae biofuel pioneer OriginOil is behind a 2009 “breakthrough” in the quest to cost-effectively extract a renewable biofuel from algae.

A study published in 2012 confirms that algal biofuels are a legitimate solution to efforts to combat lifecycle GHG emissions. The study is known as Environmental Science and Technology by ExxonMobil Research and Engineering, MIT and Synthetic Genomics. The study found that when produced in large volumes, algae has the potential to produce huge amounts of fuel per unit area of production.

The study also found that algal biofuels in saline systems using brackish makeup water can have freshwater consumption that compares to gasoline. Through a process known as “wet extraction”, there is potential for more than 50 per cent reductions in GHG emissions.

Given algae’s high oil yield, it’s estimated that about 1 percent of today’s 1 billion U.S. farm and grazing acres (as land, pond, or ocean space) could produce enough algae to replace all petroleum diesel fuel consumed in the U.S.
However, the research on algae as a biofuel is inconclusive. CSU mechanical engineering professors Anthony Marchese and Azer Yalin are amongst the researchers who are examining exactly what gases are emitted when algae oil burns. The CSU team seeks to understand how gases like nitrogen oxides (NOx) emissions are produced from burning biofuel. The outcome of their research will go a long way to determine the viability of algae as a feedstock for biofuel.

Professor Chris Rhodes is a writer and researcher who has reservations about the feasibility of algae as a feedstock for biofuel (it should be stressed that Rhodes is also a climate denier). The reason he claims he is bearish about algae is due to insufficient global rock phosphate reserves. These phosphates are required to grow algae.

The high hopes many have for algae as a biofuel may never come to fruition. According to a 2009 article by GWIR’s Thomas Schueneman titled Algae Biofuels – The Hype, the Hope, the Promise, the buzz around algae based biofuel “is wild-eyed optimism and pure hype.”

Fourth Generation

Fourth-generation technology combines genetically optimized feedstocks, which are designed to capture large amounts of carbon with genomically synthesized microbes, which are made to efficiently make fuels. Key to the process is the capture and sequestration of CO2, making them carbon neutral fuels.

Dr. J. Craig Venter said his Synthetic Genomics could lead to improvements in biofuels by letting scientists design feedstocks that capture more carbon. Venter is an American biologist who was one of the first to sequence the human genome and he is working to develop cells with a synthetic genome. His company plans to combine the processes of feedstock growth and fuel processing by designing organisms that will inhale CO2 and excrete sugars. The research was published in the Proceedings of the National Academy of Sciences. Venter’s teams are now using this knowledge to see if new biofuels can be efficiently developed.

Advanced Reactors

As reported in January 2012 issue of the journal Energy & Environmental Science and highlighted in Nature Chemistry, a team of chemical engineers at the University of Massachusetts Amherst has discovered reactions occurring within wood that could serve as the basis for designing advanced biofuel reactors. The “mini-cellulose” molecule, called ?-cyclodextrin, solves one of the major roadblocks confronting high-temperature biofuels processes such as pyrolysis or gasification. Paul Dauenhauer, assistant professor of chemical engineering and leader of the UMass Amherst research team, says that by creating reaction models of wood conversion, the scientists can design biomass reactors to optimize the specific reactions that are ideal for production of biofuels


Genetic modification and feedstock optimization may improve the outlook for non-food feedstock pathways and may expedite commercialization.
In the absence of a proven feedstock or production process, biofuels have been oversold by industry and politicians. Biofuels cannot solve all our energy problems on their own and the belief that they will leads to a false sense of security. The unwarranted faith in biofuels detracts from crucially important efficiency initiatives and undermines efforts to ramp-up abundant, truly renewable sources of energy like wind, solar and geothermal.

Source: Global Warming is Real

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