Learning by Example

08/31/2005 |

Last month’s article about the installation of a fuel-cell system at New York’s Sheraton hotel generated several e-mail responses. While I generally like to forge ahead with new topics of discussion, I honestly feel that one of the best resources we have in the building community - one of the best ways we can learn - is through the dialogue that occurs with others.

With that said, one e-mail that caught my attention was from a facility manager at JFK Intl. Airport, who, in the mid- to late-1980s, was involved in a test program that featured two 75-kilowatt fuel cells. Although I was unable to confirm the status of this program today, I think his description offers an example of a creative application that demonstrates the potential beauty of this technology:

Over a 24-hour period, the building’s hot water would vary considerably: During normal building operating hours, hot was used to the maximum, and during off-hours, there would be little to no usage. In order to realize the maximum output of the fuel cells, we had to alter the domestic hot-water system to accommodate all the rejected heat. A heat exchanger was installed between one of the building’s four 1,500-gallon domestic hot-water holding tanks and the fuel-cell radiator. The fuel cells’ rejected heat was circulated through this exchanger, which heated the domestic hot water. The heated water was stored in the holding tank and then blended with domestic cold water to put 120-degree-F. water into the building. The water temperature in the holding tank would reach 190 to 200 degrees F. when there was no hot-water demand, and [would] drop to 120 degrees F. during heavy-demand periods. Being able to absorb the rejected heat from the fuel cells kept them operating almost 24 hours per day. The fuel cells were calculated to be operating at an efficiency rate of 94 percent.

As you noted in your article, there were no stack emissions. The fuel cells, however, did make water (about 6 gallons per hour) as a byproduct of the hydrocarbon (gas) and oxygen. This was considered the only waste produced by the fuel cells. To increase efficiency, we began collecting the water in tanks and utilized it for gardening and cleaning. In fact, during a drought period in New York, we had this water source and kept all our foliage in the building alive.

High efficiency and water for plants to boot! Now that’s what I call “green building.”

In another e-mail, a reader asks about the use of fuel cells in smaller-scale projects:

The Sheraton NY project was interesting, but I find that most articles highlight big-budget applications for a big splash, which, quite frankly, have very little to do with any real impact. Real impact can only be made in the billions of small projects [that] seem to be ignored.

I’m talking about the 2,000-square-foot office building or branch bank, the 7,000-square-foot retail space, the 10,000- to 50,000-square-foot college or community college classroom building, or the 100,000-square-foot elementary school. There are thousands of these going up or being renovated for every one hotel. Is there any emphasis on and articles or information [about] applications in these types of projects?

Unfortunately, in the United States, at this time, the current cost for fuel cells is often beyond the budgets available for smaller building types. And, as is the nature of the publicity beast, we often only read about the “big-splash” projects because they do indeed make a big splash.

On the upside, however, several manufacturers of fuel-cell systems are working on developing smaller-scale equipment better suited for the types of projects you mention, and even for residential use. One such case that struck my attention was the installation in April 2005 of a 1-kilowatt fuel-cell module for use in the home of Japan’s prime minister.

The system was installed as part of a large-scale promotion by the Japanese government to protect the environment and to conserve energy. As a partner in the program, Tokyo Gas initially plans to install 200 of the units within its service area. According to Tokyo Gas Chairman Kunio Anzai, the fuel-cell cogeneration systems have the potential to reduce household energy use by 20 percent and carbon dioxide emissions by 30 percent.

Granted, Japanese household energy-use patterns are very different from U.S. energy-use patterns, but all I can say is - wow! On top of that, the Japanese government has pledged $23 million (U.S.) in subsidies to promote the effort - double wow!

And, it doesn’t stop there. According to a New York Times article that ran in June 2005, 160,000 Japanese homes have solar-power systems - installed with the help of $1.3 billion in government subsidies in order to reduce payments for foreign oil, coal, and gas (Japan imports 96 percent of the energy it needs).

The government also recently introduced a national campaign - as part of “a patriotic effort to save energy and fight global warming,” the Times reporter wrote - pushing hybrid cars and encouraging households to replace older appliances with newer equipment consuming far fewer kilowatt-hours.

If the world’s second-largest economy can do that, why can’t we?

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