Biofuel

Biofuels are touted as a cleaner alternative to fossil fuels, but they come with their own set of problems. One of the biggest concerns lies in the displacement of food crops like corn, which can raise food prices and have other indirect effects around the world on land use and agriculture.

A new production method could begin to alleviate that problem while solving another: It turns trash into biofuel.

In 2004, Wangari Maathai, a Kenyan professor, won the Nobel Peace Prize for her Greenbelt Campaign. The forestry project has planted more than 30 million trees in its 32 years, stemming deforestation across swaths of Africa and helping 900,000 African women to have decent livelihoods tending to tree nurseries and planting trees.

Trees are undeniably good things. They draw CO2 from the atmosphere and store it physically as carbon in their structure. They improve water and air quality, and protect soil from erosion and, in turn, desertification. Particularly in tropical zones, continuous vegetative cover is the only way to prevent the destruction of the soil, since, as environmental historian Colin Duncan explains,

"In many tropical places, the meager soils also have some unfortunate geological characteristics. High laterite content renders some tropical soils into concrete-like surfaces in the event that the vegetation cover is removed and they are exposed to drier conditions. Such eventualities are practically irreversible."

Still, we should be absolutely clear that greenery is not a panacea for excess atmospheric CO2.

Sometimes tree-planting can ultimately have negative effects on net CO2 emissions. One example occurs when natural or old-growth forests are destroyed and commercial monoculture tree plantations replace them.

Farm state lawmakers and agribusiness have been hammering the EPA since it announced a plan last year for evaluating biofuels by their lifecycle emissions — including indirect land use changes.

It appeared then that corn-based ethanol wouldn’t make the cut. The proposed rules, based on the 2007 Energy Independence and Security Act, required renewable fuels’ lifecycle emissions to be at least 20 percent less than gasoline's. An early EPA review calculated that, with greenhouse gases from indirect land-use changes included, most corn ethanol wasn't much better than regular gas.

The EPA has now finalized the renewable fuel standard, and agency Administrator Lisa Jackson announced today that corn ethanol will qualify after all.

“EPA has found that it is indeed 20 percent less greenhouse gas emitting than gasoline,” Jackson said. “Based on what we know now, including indirect land use analysis, there is no basis to exclude these fuels.”

What changed in less than a year?

Bio-engineering has given science a new toolbox for slowing climate change: By synthetically altering the DNA in bacteria, bio-engineers may be able to convert microscopic organisms into fuel producers.

If the science reaches its full promise, drivers a few years from now could be filling up with carbon-neutral gasoline, fresh off the bacterial production line.

This technology has the potential to revolutionize the way that we power our lives and to dramatically decrease carbon emissions, but it is still in the early stages of development. That could change with a boost from the U.S. Department of Energy, which has sought to spur growth in low-emissions energy technologies through the recently established Advanced Research Projects Agency-Energy (ARPA-E). The aim is to invest in high-risk, high-rewards innovations that stand to transform the global energy landscape.

"With ARPA-E, we are swinging from the heels and trying to hit home runs, not just base hits. The 37 projects we're funding span the spectrum—from renewable energy, to energy storage, to industrial and building efficiency, to petroleum-free vehicles and carbon capture," Energy Secretary Steven Chu said.

Even one break-through in any of these areas could be a major step toward solving climate change.

Sugarcane is touted as the miracle biofuel even by biofuels' skeptics.

Former President Bill Clinton lauded it at the recent Brazilian ethanol summit, held in São Paulo (although he warned of the dangers of deforestation). Sweden views sugarcane ethanol as a relatively clean proxy for petroleum and has sought to lower EU import tariffs on it, the better to have a more “renewable” energy profile.

By some measures, sugarcane ethanol deserves the accolades.

The governing metric for determining the quality of a given biofuel is the EROEI, or the energy returned on energy invested. For Brazilian sugarcane ethanol, the number is frequently reported as eight or higher—that is, for every unit of fossil energy input, eight units of sugarcane ethanol energy are output. Pretty good.

Except for a niggling problem: The ecology is a bit more complicated than an EROEI calculation. For one thing, a recent study in the journal Science suggests that conversion from rainforests, peat-lands, savannas or grasslands to biofuel plantations can create huge carbon debts that will take decades to repay: