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Gradient rethinks the window air conditioner

USA: A San-Francisco-based start-up company has developed a quiet and efficient heat pump air conditioner to replace the conventional window AC unit without actually blocking the window.

The company, Gradient, says it will replace the conventional home window AC with a more efficient, space-saving, better-designed solution that keeps homes cool with advanced heat pump technology and a climate-friendly refrigerant. 

Previously known as Treau, Gradient was spun out from Otherlab, a private R&D lab in San Francisco.

The saddle-mount air conditioner is described as a plug-and play-unit that can be installed by the layman in about 15 minutes, providing the benefits of a heat pump at a fraction of the cost of a split system. 

The current model uses R32 refrigerant but the developers maintain that the goal is to move to “natural” refrigerants in the future. The current design is said to be about 30% more efficient than traditional window ACs. 

Technical details are scant, but the unit is thought to employ an improved heat transfer loop with patents pending on a new design roll-diaphragm compressor and heat exchanger.

Gradient says the air conditioner will be available for sale nationwide in Spring 2022, but customers are currently being invited to sign up for the exclusive beta programme. 

The company was founded in 2017 by thermal scientists and engineers and flanked by talent from pioneering companies like Tesla and Nest. 

Gradient has already raised over $13m in venture funding. Investors include Ajax Strategies, At One Ventures, Prime Coalition, Incite Ventures, Autodesk Foundation, Urban Us, Magic Hour, and leading Silicon Valley angels. The company has also received over $9m in government grants from the US Department of Energy, California Energy Commission, and California Strategic Growth Council.

“Home air conditioning is an underrated aspect of the overall conversation around climate change, and we see a big opportunity for Gradient to disrupt the home HVAC space by developing a much-improved, climate-friendly replacement for the traditional window unit AC,” said Milo Werner, partner with Ajax Strategies. “Millions of Americans need an air conditioning solution, but their options are limited to out-of-date window and floor units that block their view, make a lot of noise, and contribute to climate change.”

Gradient

Related stories:

California offers $4.7m to develop advanced ac28 January 2019
USA: California’s US lead in restricting the use of HFC refrigerants has been backed by a $4.7m grant to develop advanced residential HVAC systems with low GWP refrigerants. Read more…

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