New York City and the like are full of old buildings that are mostly nice, except that they aren’t all that comfortable to live in. Built at a time when huge boilers were state-of-the-art, the buildings are usually too hot or too cold, but rarely exactly so.
There are companies trying to fix this by using smart horseshoe-shaped heat pumps. On the surface, they look like window air conditioners, except they don’t block the view and can heat and cool.
Slope makes one of those heat pumps, but now adds a twist: In multifamily buildings, it can connect all the window units together. The startup shared with TechCrunch exclusive details about the new Nexus software and service.
“Multifamily buildings are an area that is being ignored,” Vince Romanin, chief technology officer at Gradient, told TechCrunch. “It’s a place where we can do better for the user.”
The startup primarily targets old buildings in need of HVAC upgrades. Gradient partnered with the New York City Housing Authority to install its heat pumps in public housing and ran a pilot program in Tracy, California, in a newer two-story affordable housing complex. We’re also talking to colleges and universities, many of which have dorms that weren’t built with warm fall weather in mind.
Older buildings often have an electric meter, which can tempt residents to overuse their heating or air conditioning. Nexus returns control to building managers. They can put guardrails in place to prevent people from overusing the heat or AC—either intentionally or otherwise—while still allowing them to be comfortable. In one case, a building manager set the heating limit to 78˚ F, and the next day energy consumption was reduced by a quarter.
Romanin said Gradient’s heat pumps are the “lowest cost option” for old buildings with boilers reaching the end of their lives, a common occurrence in New York. As a bonus, units that previously only had steam heaters now get air conditioning, protecting the units from worsening heat waves in the future.
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By installing a window unit instead of a micro-division, the retrofit can be done in a matter of hours. They also don’t require electrical upgrades, Romanin said. In buildings with old electrical wiring that can’t support a full 12-amp load on a single outlet, Nexus can reduce the draw, said Mansi Shah, senior vice president of products and software at Gradient.
This strategy can be extended beyond the building. When the grid is overwhelmed by demand, which can happen on hot summer days, Gradient is working on a way to call back the heat pumps while maintaining passenger comfort. Using information about the building along with feedback from sensors on the heat pumps, the company hopes to predict which units can reduce air conditioning demand, such as those on the shady side of a building. This kind of demand response can help the grid serve more heat pumps without requiring expensive upgrades.
“There are a lot of people who have said that when we electrify everything, the grid won’t handle it,” Romanin said. “I think it’s very likely that everything will be electrified and the grid will become better, the grid will become easier to work on and electrons will become cheaper.”
