A project implemented by Chicago-based Patrick Engineering Inc. at the Metcalfe Federal Building in Chicago is a primary
example of a fairly simple, yet innovative implementation of solar energy. The project was part of Greening the Government
through Efficient Energy Management, an executive order that mandates that the federal government improve energy management to
save taxpayer dollars and reduce emissions.
Bill Taylor, senior project manager with Patrick Engineering, said that the major question was how to get 21 solar panels
on the roof of a 30-story building in Chicago. Because these panels were being installed on a structure so high, the wind
played a major factor.
"We designed a fairly elaborate steel support system to hold the panels in place," Taylor said. "This brought about the
problem of getting the steel on the roof, too. We made sure the system we put into place was sturdy enough to hold these
panels in place."
A freight elevator was used to lift the steel supports and the solar panels, but it stopped one floor before roof level. It
was then necessary to hoist them through a hatch the rest of the way.
"It was a fairly labor-intensive project," Taylor said. "The steel plates are four by four feet and the panels are about
five by eight feet. Traditionally, most solar installations are on a one- to two-story building."
The panels allow the supplementation of the utility source (especially in summer, which is high-peak capacity time). The
system connects into the existing electrical system and energy is routed through a converter.
"We had previously completed small-scale solar installations but none that would provide this level of output," Taylor
said.
The project only took about three weeks and was completed in fall 2000, but Taylor said that was working at a pretty
intense pace.
The system is equipped with a computer system that helps to determine how much supplemental energy is being supplied.
"Even on a cloudy day, you can see there is output," Taylor said.
The steel frames are adjustable and can be tilted at different angles for summer, fall, spring and winter settings.
"In the summer you lay them almost flat to obtain the most heat because the sun is at its highest point," Taylor said. "In
the winter, the sun is so low, they need to be stood almost straight up and in the fall and spring, they are tilted somewhere
in the middle, facing the sun."
The 10-kilowatt system was the first building in Illinois and the first federal building in the Midwest to receive the
Energy Star label, the mark of excellence in energy performance.
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The Metcalfe Building solar installation is part of the Million Solar Roofs Initiative that is enabling
businesses and communities to install solar systems on 1 million rooftops across the United States by 2010. The Department of
Energy is working with partners around the country to remove barriers and strengthen the demand for solar technologies.
Bob Vogle, president of the Illinois Renewable Energy Association, said that through the Solar Partnership in Chicago, the
Spire Corp. is installing photovoltaic (solar systems) in schools and other public buildings in an effort to reduce energy
costs.
This program, initiated in Chicago, is supported through the Illinois Department of Commerce and Community Affairs.
Commonwealth Edison and the City of Chicago have made additional contributions.
"In addition, IREA puts on workshops for people interested in installing such systems," Vogle said.
Last year, IREA presented an Illinois Renewable Energy fair with about 1,500 participants exploring renewable topics,
relating not only to photovoltaics, but other alternatives such as wind and biomass.
"We promote solar and 'renewables' in general," Vogle said.
Mounted solar panels are one way of acquiring solar energy. Vogle said that a new business alliance in California is
developing a product that will integrate the solar cells into a polymer type of roofing.
"It will lay down on a thin, plywood-type of board and become, in effect, a part of the roof itself," he said. "That offers
a real cost savings on installation."
Ethanol falls into the category of a biomass renewable energy source. Soybean diesel and recycled scrap logs are other
alternatives. But at this time, Vogle said a large wind farm is probably the most cost effective in terms of producing
electricity.
"A 40-megawatt system is to be installed in the Princeton area," he said. "These are very large machines in the air about
300 feet. The windiest areas that are close to power lines can produce enough electricity to be almost competitive with coal."
Vogle said that in terms of how much energy must be produced, a basic guideline is that a four-kilowatt system would serve
an average household. And that household in Illinois uses about 800 kilowatts a month.
"The wind farms are the most developed industry now, but I think we're going to see expansion of the roof systems," Vogle
said. "It continues to improve. I think there will be much more widespread use of that."
graphic designer and staff writer: Vicki Bennington
email: vbennington@ibjonline.com
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