Kellenberg High to expand 'solar' system

For the past two years, cafeteria dishes at Kellenberg Memorial High School in Uniondale have been washed in water heated by 120 6-foot-long glass vacuum tubes arrayed in solar panels on the building's roof.

Come September, there will be many more of those tubes: 3,450, to be precise, facing south at a 45-degree angle to catch the sun's rays. In colder months, the tubes will help heat the school's water and warm its classrooms; in summer, they will help cool them down.

An official from the New York State Energy Research and Development Authority, Dale Zatlin, said she believed it would be the first "solar thermal" system in the state that both heats and cools.

Brother Gary Eck, a Kellenberg math teacher leading the installation project, said at a rooftop news conference Monday the system could slash a $300,000 annual electricity and gas bill by 10 percent. "I've been out here in January, days where the wind was blowing and it was 10 degrees, and we were getting 175-degree water," he said.

The system, to be installed by Brooklyn-based New York Solar Systems, is funded through the state Energy Research and Development Authority by $945,000 in federal stimulus funds. Hempstead cut $11,500 in permit fees to $300.

Here's how it will work, according to Chester Birchwood, designer for New York Solar: The specially designed glass vacuum tubes absorb the sun's heat and provide heat insulation. A copper "heat pipe" then transfers heat from the tubes to a small exchange tank nearby.

In heating mode, water from the tank is carried to a 3,500-gallon tank in the basement; from there, hot water is pumped throughout the building through pipes that radiate heat.

In cooling mode, hot water from the exchange tank is transferred to a separate basement tank where, instead of circulating immediately, it is used to heat a salt water solution in a separate chamber to boiling. As the solution evaporates, it extracts heat from the chamber. Water that is piped through is chilled and then pumped throughout the building. "The best analogy I can give you is when you take an aerosol can, and shake vigorously, it's cold to the touch," Birchwood said.

While New York Solar Systems employees were hopeful Kellenberg might one day feed energy back into the grid, Brother Gary said on most winter days, the school needs all the heat it can get.

And, he said, a renewable energy system has benefits beyond dollars and cents. "We are participating in God's creative activity," he said. "Using energy well is part of that."