 Developer Ken Dearden shows one of ten geothermsal wells that are part of the geothermal system being installed at 66 Main Street in Yonkers Sept. 25, 2007. (Stuart Bayer / The Journal News) Going green to make more green Developer Ken Dearden shows one of ten geothermsal wells that are part of the geothermal system being installed at 66 Main Street in Yonkers Sept. 25, 2007. (Stuart Bayer / The Journal News) Kenneth Dearden, one finger raised toward the ceiling, walks through the dusty ground floor of a luxury rental-apartment building he is building in downtown Yonkers. Dearden, a diminutive man who always seems to be in a rush, is showing a visitor the route of the piping that is part of the geothermal heating and cooling system in the 170-unit building being built by MetroPartnership - a joint venture between Dearden and Teaneck, N.J.-based Kohl Partners. Ten wells will pull water from 1,500 feet below the sidewalks on Hawthorne Avenue and Main Street so that it can be pumped into the building's geothermal system. "We know tenants are sensitive to things like utility bills," Dearden said. "That's one of the things people ask. They want to know how much the utility bill is going to be." Dearden, a mechanical engineer by training, said he does not have a precise answer as to how much the average utility bill will be in the complex at 66 Main St. But he said the geothermal system will save about half off a tenant's air conditioning bill and about a third off the heating bill. The savings on air conditioning are greater, he said, because an apartment - unlike a house - usually has only one wall facing the outdoors. And modern households tend to be filled with electronic gadgetry that throw off heat, he noted. He also acknowledged that the partnership would not have chosen a geothermal system if the economics didn't make sense. The developers will spend $500,000 to $1 million more to drill wells than they would have spent to put a cooling tower on top of the building, he said. Grants from the New York State Energy Research and Development Authority will offset some of that extra cost. Colleen Ryan, a spokesperson for the authority, said the agency will inspect the system once it is fully installed and determine the amount of the grant. The preliminary estimate is $136,490, she said. It would be the first geothermal system at a Westchester apartment complex NYSERDA has helped fund, she said. The bigger benefit, Dearden said, is that the apartments will be more marketable, meaning the vacancy rate will be lower. The water, 55 degrees Fahrenheit when it comes out of the ground, will circulate into three devices called heat exchangers where it will either absorb heat from water that will circulate through the building or add heat to the water that will circulate through the building, depending on whether it is providing heat or air conditioning. The water from the wells eventually returns to the ground. The water circulating through the building will go to the heat pumps being installed in every unit. The heat pumps contain a chemical refrigerant and a compressor just like a refrigerator or a through-the-wall air conditioner. The heat pumps either take heat out or add heat to the circulating water. The consistent temperature of the groundwater is the key to making the system work, Dearden said. "This is, for lack of a better word, free," he said of the water. "It comes out of the ground at 55 degrees and you don't have to do anything to it, except pump it. The second reason that it's so efficient is that it's a very low temperature, so it's very good for making air conditioning." The geothermal system also does not require maintenance, whereas as electric-powered cooling towers on a building's roof need to be pumped out in the winter because the water can freeze. Cooling towers also need to be cleaned if algae builds up and can require other attention, he said. The geothermal system also eliminates the need for oil or gas-fired boilers to heat the building, keeping emissions from spewing into the air. Geothermal technology is not new but it is not widely used in the United States. In 2005, less than one-third of 1 percent of the energy consumed in the United States was from geothermal sources, according to the U.S. Energy Information Administration. The numbers show the use of geothermal energy increased at a nearly undetectable rate during the first five years of the decade. It lags well behind solar and biomass as an energy source for residences, the EIA statistics show. Jon Nolan welds a piece of pipe as part of the geothermal system being installed at 66 Main Street in Yonkers Sept. 25, 2007. (Stuart Bayer / The Journal News) Besides apartments, which will rent between $1,400 (for a studio) and up to $2,800 (for a two-bedroom) the 10-story building will contain retail space. The first apartments will be on the market in November, Dearden said. MetroPartnership also owns Metro92, formerly known as the Trolley Barn, a 40-unit loft building on the next block |
