How an NYC high-rise is keeping cool with geothermal energy

A commercial office building in Manhattan, 555 Greenwich St., has become New York City's first fossil-fuel-free commercial office building, according to its owners. The 16-story building uses 68 geothermal piles that run nearly 120 feet underground, moving heat into the earth in summer and pulling it back out in winter. This system, paired with large rooftop air-source heat pumps (which move heat using electricity rather than burning gas), covers all the building's heating and cooling needs. The owners estimate the building will save around $3 million in energy costs over 15 years.

The building is part of a larger effort in New York City, where laws are pushing new construction and large existing buildings toward electric, fossil-fuel-free systems on set timelines through 2030. A neighboring, century-old building is being retrofitted floor by floor with heat pumps and a shared water-pipe network that moves heat where it's needed, funded partly by a $5 million state grant plus private money.

For homeowners, this is mostly a signal of where heating and cooling technology is headed rather than something with immediate rules attached. Geothermal and heat pump systems, once mostly discussed for large buildings, are increasingly proven at scale in dense cities. The article also notes that New York state recently weakened a major climate target, which is creating some uncertainty among building owners about how firm future deadlines really are — a reminder that state and local rules can shift, even as individual buildings push ahead with upgrades on their own.