Powering the Future
By Lily Auliff

Energy production and use accounts for almost 80 percent of all air pollution in the United States, according to the Alliance to Save Energy. But fuel cells, like the ones being tested by the Houston Advanced Research Center (HARC), may help change all that.

HARC’s role is to test and evaluate fuel cell technologies, rather than develop them. “We want to help bring fuel cells from development into commercialization,” explains Bruce Rauhe, Technical Director of the Center for Fuel Cell Research and Applications at HARC. “We partner up with groups who want to evaluate the technology and new applications.”

Since its inception in 1998, the center has participated in four fuel cell projects.

HARC is working with the Port of Houston Authority to install a large 200-kilowatt fuel cell. “When a container ship comes in to dwell in port, we will plug the fuel cell into the ship’s electrical system,” Rauhe explains. “Our goal is to provide as much shore-based power as possible to help them throttle down those polluting diesel generators.” HARC estimates that using the fuel cell could reduce nitrogen oxide (NOx) – a principal component of ground-level ozone – emissions from the port by about 0.2 tons per day.

The group is working with numerous government and industry agencies to fund the Port of Houston project. Once underway, it will run for approximately two years.

HARC is also helping Bush Intercontinental Airport install a 250-kilowatt fuel cell. “The airlines are converting some of their ground service equipment from diesel to battery powered electric,” explains Rauhe. The fuel cell will provide power to the chargers that juice up the vehicles. “That one 250-kilowatt fuel cell should reduce NOx emissions by about 0.7 tons per day,” notes Rauhe. The project is primarily funded through a Department of Transportation grant and will run two years.

In a shorter-term project, HARC provided technical expertise to the Texas Natural Resource Conservation Commission and others, who installed a three-kilowatt system that now powers air monitoring equipment in Austin.

To test stationary proton exchange membrane (PEM) fuel cells, a lightweight type appropriate for many applications, HARC organized a diverse consortium of potential users: Dana Corporation, Salt River Project, Southern Company, Texaco Energy Systems Inc., and Walt Disney Imagineering Research & Development, Inc.

The companies, which fund the project, represent diverse perspectives. A couple of them are power providers, interested in fuel cells as generation sources, while others would like to supply parts to the up-and-coming fuel cell industry. Some are just interested in using the technology once it is fully developed. “We wanted different people so we could bring ideas to the table on how we should look at these fuel cells,” notes Rauhe.

HARC currently houses one small PEM fuel cell for the consortium, with five more on the way this year. Researchers use them to test power quality and reliability, as well as collect long-term performance and emissions data. The three-year PEM project will be completed by December 2002.

Fuel cells combine hydrogen and oxygen to produce electricity, heat, and water, so the only emission is pure water. “The oxygen is usually provided by air, but the hydrogen can be tricky,” explains Rauhe. “Hydrogen doesn’t exist naturally in its pure form. It is always combined with something like carbon or oxygen. Generally, we get our hydrogen by removing it from a hydrocarbon, like natural gas or propane.”

Chemically, hydrogen atoms release electrons at one electrode in the fuel cell. The hydrogen ions and electrons recombine at the other electrode with oxygen to form water. The transfer of those electrons is what gives fuel cells their power.

Because fuel cells generate electricity from an electrochemical reaction rather than combustion, emissions are minimal. When hydrocarbons are used as the hydrogen source, some carbon dioxide is produced, but much less than comes from burning fossil fuels. Fuel cells also tend to be more efficient than other energy sources, and because they are located at the point of use, less power is lost through transmission and distribution.

A current debate focuses on where the hydrogen to power fuel cells will originate. Rauhe expects that fuel cells in homes will run on natural gas in areas where it is available, and on propane in other places. For cars, the source is questionable. Some advocate straight hydrogen, which is clean but difficult to store. Others, including Exxon and General Motors, are vying for gasoline, perhaps the simplest solution in terms of infrastructure development, but more polluting. Natural gas is also a possibility.

When will the public start to see fuel cells in homes and cars?

“Technically speaking, you can probably buy a fuel cell power system for your home this fall, but the price would be exorbitant,” says Rauhe. “As the volume of fuel cells grows – as people buy more and more – the price will come down.”

“According to car manufacturers, we’ll see quite a few fuel cell-powered cars in demonstration fleets around 2004,” he adds. “They expect the vehicles to be on the commercial market around 2007 or 2008.”

For more information on HARC’s fuel cell research, visit www.harc.edu/fuel-cell.