After two decades in the construction industry, California entrepreneur Sasha Jokic is going prefab. His new company, Cosmic, makes energy-efficient homes that property owners can easily add to their backyards as accessory dwelling units (ADUs)—and each packs an off-grid punch.

“It's hard to distinguish our system between a power plant or a house, and we like that,” says Jokic. “We see our home as a backyard unit that gives people additional living space, but also, it’s a giant power bank for the entire house.”

Cosmic’s ADU design, with its steel-framed floor-to-ceiling windows and timber cladding, is a sight for sore eyes. But more attractive is its astounding energy performance promise. A rooftop solar array and built-in energy-storage system produces more than a unit can consume, says Jokic, and so much more in fact that the leftovers can fully power a primary residence.

Cosmic’s first two models are a studio and a 1-bedroom unit that range in size from 350 to 1,200 square feet, both of which have customizable layouts. The interiors have a natural feel with flooring, walls, and ceilings all finished with wood. Floor-to-ceiling windows give the units a clean, contemporary look while capturing an abundance of light.

“Usually when people talk about energy efficiency, they think the windows have to be smaller,” says Jokic. “We see the opposite. If you create a robust energy system, you have more freedom in terms of the window openings. As well, we’re investing into two-pane or three-pane windows that are highly efficient.”

The ADUs start at $190,000 but can be financed with no money down, says the company. Buyers can pay monthly, and would earn credits through the energy produced by their unit.

Looking forward, Jokic hopes to scale Cosmic beyond single-family living. “To really fulfill our mission is to scale to multifamily,” he says. “You have more solar power capabilities, larger energy storage, and you can experiment with different types of renewable energy produced at home. So I think it’s going to be really interesting, the future of Cosmic.”

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