A seminary in the heart of New York City is drilling to a depth of from 1,500 to 1,800 feet to pump 65 degree (F) water for a new geothermal heating and cooling system for its Victorian era complex, the New York Times reports.
The General Theological Seminary of the Episcopal Church has so far drilled seven of a planned 15 wells half again as deep as the Empire State Building (with 102 floors) is tall.
The seminary joins about 60 other places in Manhattan using geothermal pumps to harvest energy from deep streams running below the island. Groundwater seeps through a network of fractures in the rock under Manhattan, caused by continental collisions eons ago, creating permanent streams, the New York times quotes a U.S. Geological Survey scientist.
When finished, the project will be the biggest system of geothermal pumps in the Northeast. The initial stage was estimated to cost $6 million, but cost $9 million for heating and cooling capacity in 80,000 sq. ft. of the buildings' 260,000 sq. ft.
The investment is projected to pay for itself in about 19 years. "It won't be the five-year return on investment businesses want, but that is fine," said Maureen Burnley, executive vice president of the seminary. "We're going to be around."