No one really likes window air conditioners: Yes, they can make a hot day more bearable, but they’re also ugly, noisy, block the view, and contribute to climate change. But the number of air conditioners is poised to surge, both because the planet is getting hotter and a growing number of people in developing countries can finally afford the technology. By 2050, by one prediction, there will be 5.6 billion air conditioners in use, up from roughly 1.6 billion now.
Several companies are trying to find ways to solve the problem. Gradient, a San Francisco-based startup, is designing an alternative that can help tackle the challenges of traditional air conditioners—and that doubles as an efficient heater when it’s cold. When it’s used both for heating and cooling, the device can shrink the carbon footprint of heating, ventilation, and air-conditioning (HVAC) by 75%. As the grid shifts to renewable energy, that footprint could essentially be eliminated completely, so turning on the AC doesn’t have the ironic effect of making future heat waves more likely through global warming.
“We realized that air conditioning is an important public health need,” says Vince Romanin, CEO of Gradient, which spun out of the research and innovation lab Otherlab, a company that studies the energy system in detail and designs new solutions. “And we realized that we’re in kind of a vicious cycle where today’s systems are really high carbon emissions and growing in use. It doesn’t have to be this way—technology exists to make heating and cooling systems that don’t have high carbon emissions. The company’s here to break this cycle, and make products that allow you to be cool and comfortable without heating the planet,” says Romanin.
Some more efficient air conditioners already exist, but they tend to require professional installation and that drives up the cost. “People typically buy the lowest efficiency product on the market,” he says. “And that’s because upfront costs are just a lot for people to handle.” Gradient designed its device to work like a more expensive heat pump (technically, all air conditioners are heat pumps, but the industry uses the term to refer to devices that can both heat and cool), but because it’s easy to install, the buyer can do it themselves. The company hasn’t released the price of the units yet, but says that it’s aiming first to make the most efficient technology accessible to more people. Eventually, it wants to be able to compete with the lowest-cost air conditioners.
Since refrigerants in air conditioners are potent greenhouse gases, the company also chose a low-emission refrigerant that goes beyond what regulations require for the industry. Unlike a typical air conditioner that has two options—on and off—the Gradient device has a variable speed drive so it can turn up and down, using only the amount of energy needed. It’s connected to Wi-Fi, so it can also help adjust itself when there’s heavy demand on the electric grid. The device also reduces emissions by replacing fossil fuel-powered heat in the winter. (For now, it’s only suited for relatively warm climates, though it can help people in colder climates turn down their other heaters, and the team is working on making it better for extreme winters.)
The company isn’t trying to persuade customers to buy the product based on the climate benefits, but because it hopes that they’ll prefer the experience. It sits below the window, so light still comes in. It’s large, but not an ugly box. The noisy components are outside, so it’s quieter than traditional units, and the variable speed drive also helps lower the volume.
“We don’t think that the way to push an industry forward is to ask people to pay for their reduction of their carbon footprint,” Romanin says. “We want to build products that provide a better user experience, and that make their homes comfortable and nicer looking. In all other industries, you see that that’s really the thing that drives change fast enough to have an impact. And when it comes to emissions, we really don’t have a ton of time. We need to start replacing fossil fuel furnaces and inefficient HVAC as soon as possible if we want to hit our climate reduction targets. So we need to make the product that people want on its own merits, so that we can drive adoption as fast as possible.”
The company is looking for participants in a beta trial of the devices now, and plans to begin commercial production in 2022.
