The recent run-up in gasoline prices was a not-too-subtle reminder that there's a limited amount of oil on Earth. Someday soon, we're going to need a new source of fuel.
Part of the answer could be fuels made from the plant material cellulose. Researchers at the new Energy Biosciences Institute at the University of California, Berkeley are working on a recipe for this biofuel.
From Plant To The Pump
The institute is trying to make at least part of the economy run on fuel from vegetation. It has taken over a lab building once used to answer the purely scientific question of how plants convert carbon dioxide into chemical energy. Now, Christopher Somerville and his colleagues hope to exploit that chemical energy by converting cellulose into fuel.
Cellulose is really nothing more than sugar molecules — glucose — all linked together with indigestible chemical bonds.
"Glucose is the principal fuel of all life on the planet," Somerville says.
The challenge is to liberate all that energy-rich glucose from the cellulose. If it can be converted to simple sugar, it can either be fed to yeast, which will turn it into ethanol, or it can be converted chemically into liquid fuels that could directly replace diesel and gasoline.
Converting plant cellulose into fuel could transform the economy with a less damaging alternative to fossil fuels. Fuel made from cellulose is relatively clean because the plants that it comes from actually get their carbon out of the atmosphere. So, carbon cycles from the exhaust pipe into the air, back to the plants and then to the fuel again.
Somerville says researchers already know how to convert cellulose into fuel. In fact, about 20 start-up companies are already making small amounts of fuel from cellulose.
"It's not like fusion," Somerville says, "where it really doesn't work. This is something that works and just needs to work a bit better in order to make it compete with fossil fuels."
To be competitive, Somerville's institute needs to develop not just a fuel but an entire industry — and the researchers want to make sure this new industry is green and socially responsible.
The Key Ingredient
The first question is what starting ingredients to use. One of the first to be tested is Miscanthus, a relative of sugar cane that looks a bit like bamboo or straw when it's dry.
"It's native to Southeast Asia," Somerville says, "and has been used in Japan and China for a thousand years for thatching, and also for making paper."
The institute will look at many different species, but researchers like Miscanthus because it grows fast with no fertilizers, no irrigation and no chemicals.
Whatever plant is used, farmers will have to grow millions of acres if the industry is going to compete with fossil fuels. Somerville says it's important to find a plant that will not displace food crops. That's where corn-based ethanol is failing — and why corn is not on the menu in Berkeley. But even nonfood plants such as Miscanthus could be bad news if farmers decided to plant it instead of food or cut down the rain forest to grow it.
"We're only interested in it, frankly, if it can be environmentally positive and socially positive," Somerville says. "So as we proceed with the technical innovation, we want to make sure we understand these other dimensions, and so that we can make appropriate choices, including one possible choice is that we shouldn't do this."
That's something the sponsor of this research might not want to hear. That's because the lab is funded by one of the world's largest oil companies, BP. It has committed $500 million over 10 years. At first blush, it seems strange that the company is putting this technology to the test, on one of the most progressive campuses in the country. But BP Vice President Paul Willems says the choice is deliberate.
"If biofuels are going to become a big part of our company in the long run, then our view is the only way that can be the case is if biofuels are done in a sustainable way that is clearly good for the environment and land use," Willems says. "We don't want to be building a big part of our company on a shaky foundation."
Even assuming all these issues can be resolved, the blueprint for a biofuels industry is still not complete. The final piece will have to be government policies and regulations that create incentives for clean fuels.
"Generally, business is very much in favor of a regulatory environment which is predictable," Willems says. "People don't like a regulatory environment which is on the left one day and on the right the next day, and just flip-flops back and forth, because it doesn't provide a context in which you can make 20- and 30-year investments."
To create that context, governments would need to commit in the long term to cleaner energy sources and then stick with those plans over the course of dozens of election cycles — not an easy task. Berkeley professor Dan Kammen, who helped found the institute, says the long-term government policy should try to solve two problems at once: providing energy while taking steps to slow climate change.
"Certainly, the ability to reduce carbon emissions has got to be front and center on that list," he says.
Kammen is not convinced that cellulose-based biofuels will be the answer. But he says as long as the goals are articulated correctly and funding for research is ramped up, people will come up with recipes for fuels that move us around and that aren't too hard on our planet.