engineers in the bowels of a nearly century-old apartment building drilled 14 holes to a depth of 500 feet to install a heating system that taps the constant temperature of subterranean rock

In a U.S. first, they used a compact drilling rig that fits inside a basement.

Only the boiler, cooling unit and radiators serving the Beresford’s common areas were replaced

new system will cost half as much to run as the old one and need replacing far less often

federal, utility, and $500,000 technology grant from New York State

holes were drilled beneath a new building that went up next door

smaller rig used at the Beresford, along with a quieter, water-powered drill, came from a company in Sweden, where these operations were pioneered

Hermantin says perhaps 10,000 New York buildings could get the Beresford treatment

challenge – mapping out water pipes, fiber-optic cables and other underground infrastructure like the nearby subway to ensure the 4.25-inch drill holes didn’t hit anything important


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