Building better buses - Page 2

AC Transit pushes hydrogen fuel cells as oil companies pull back
Chevron helped greenwash its image by supporting AC Transit's hydrogen fuel cell program before pulling out this September

Maybe not yet, but between the global warming impacts of oil and the increased cost of extracting oil after the most readily available supplies peak, there is a pressing need to develop alternatives to fossil fuels.

"The oil companies were getting all sorts of pressure to get off oil and carbon so they go out looking for an alternative that looks good and takes the longest to implement. Hydrogen is perfect," said David Redstone, editor of Hydrogen and Fuel Cell Investor, who has covered hydrogen for more than 10 years.

After studying hydrogen for so many years, Redstone has become skeptical about its real potential. "I was a believer when I started," he told us. "I learned a lot. I knew a lot less when I started. I knew a lot less about the engineering and cost issues involved."

For example, fuel cells require platinum, which acts as a catalyst to help burn hydrogen fuel. There is ongoing research to reduce the amount of platinum needed in a fuel cell, and exploratory work with less expensive catalysts like nickel. But for now and in the foreseeable future, hydrogen is still a very expensive technology. "They've been demonstrating these fuel cell buses for 20 years. It's like the mentality at the companies involved is that it's perfectly normal to be a demonstration technology forever," added Redstone.

He believes that the realistic solutions to the overuse of fossil fuels lie in a mix of behavioral changes and economic incentives, not technological silver bullets. Stop suburban sprawl, get people to live closer to work, and start taxing carbon. Or in Redstone's simpler terms, you've got to put an end to "assholes commuting 75 miles to work in a Hummer."

The International Panel on Climate Change estimates that surface temperatures will rise 2 degrees to 11.5 degrees Farenheit in the 21st century. Greenhouse gas emissions are a major contributor to global warming.

The promise of hydrogen fuel is that its only emission is water. The major criticism of the move toward battery electric plug-in vehicles has been that the power to charge batteries comes from a power grid that is frequently a heavy greenhouse gas emitter. Half of the electricity generation in the U.S. comes from coal, the dirtiest of the fossil fuels.

But the hitch with hydrogen fuel is how to make it. You can't drill for hydrogen, you have to create it in a process that requires energy. The predominant source for hydrogen fuel is natural gas, which emits less carbon than gasoline but is still a fossil fuel.

The holy grail of alternative energy is an efficient method for making hydrogen fuel from water instead of natural gas. The problem has been the significant amount of energy required to electrolyze water, to split apart H2O to make hydrogen fuel.

Levin believes he has the beginning of an answer. Before the end of 2010, AC Transit will complete its installation of a solar-powered proton electrolyzer in Emeryville. Solar panels will be built atop the roof of the hydrogen fueling station and the solar energy trapped will power the electrolyzer, in turn producing hydrogen fuel from water, hopefully about 60 kilograms per day, enough to power two buses. Levin received $6.4 million from the American Recovery and Reinvestment Act for the project. The remaining 10 hydrogen fuel cell buses will rely on hydrogen fuel made from natural gas.

As important as the production of hydrogen fuel are the pump stations to deliver it. Gov. Arnold Schwarzenegger's promised "hydrogen highway" hasn't happened. The initial plans called for 50 to 100 stations by the end of 2010, and a station every 50 miles, but there are now just 21 stations clustered in urban areas. And with oil companies withdrawing their support and government agencies hurting for resources, the hydrogen highway remains as far off as ever.