New York City and others like it are filled with old buildings that are for the most part fine, except that they are not all that comfortable to live in. Built in an era when massive boilers were cutting-edge technology, buildings are usually too hot or too cold, but rarely just right.
There are companies that are trying to fix that by using a clever horseshoe heat pump. Shallow, similar to window air conditioning, except that they do not block the view and they can heat as well as cool.
Gradient makes one of the heat pumps, but now it adds a twist: In multifamily buildings, can connect each one of the window units together. The startup shared with TechCrunch exclusive details about the new Nexus software and services.
“Multifamily building is an overlooked sector,” Vince Romanin, chief technology officer at Gradient, told TechCrunch. “This is a place where we can do better for users.”
The startup typically targets older buildings in need of HVAC upgrades. Gradient has worked with the New York City Housing Authority to install heat pumps in public housing, and ran a pilot in Tracy, California, in a new two-story affordable housing complex. It also speaks to colleges and universities, many of which have dormitories that are not built for the warm fall weather.
Older buildings often have one electricity meter, which can tempt residents to use heating or air conditioning. Nexus gives some control back to the building manager. They can set guardrails to prevent people from overusing heat or air conditioning – either intentionally or otherwise – while still allowing people to be comfortable. In one example, the building manager set the heating limit at 78˚ F, and the next day energy consumption dropped by a quarter.
Romanin said Gradient heat pumps are “the least expensive option” for older buildings with boilers that have reached the end of their lifespan, a common occurrence in New York City. As a bonus, the unit that previously only had a steam radiator now gets air conditioning, proofing the unit from worsening heat waves.
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By installing window units instead of minisplits, the retrofit can happen in a matter of hours. They also don’t require electrical upgrades, Romanin said. In buildings with old electrical wiring that cannot support a full 12 amp load on a single outlet, Nexus can reduce the draw, said Mansi Shah, senior vice president of product and software at Gradient.
The strategy can also extend beyond the building itself. When the box is overwhelmed by demand, which can happen on a hot summer day, Gradient is used in a way to call back the heat pumps while still maintaining the comfort of the occupants. By using information about the building and feedback from the sensors in the heat pump, the company hopes to predict which units can reduce air conditioning demand, such as those on the shaded side of the building. That demand response can help the grid serve more heat pumps without the need for expensive upgrades.
“There are many people who say that if we electrify everything, the grid will not handle it,” said Romanin. “I think it’s possible to electrify everything and make grids better, make grid tasks easier, and make electrons cheaper.”