Over the past three years, a Denver startup company has developed, tested and patented a filter for windows that is expected to reduce energy consumption in buildings by 40 percent.
RavenBrick’s thermoreflective filters use nanotechnology to transition from a transparent to a reflective state in response to changes in the outside temperature. The transition allows a building to use the sun as a source of free heat on cold days and block solar heat effectively on hot days.
“We want to harness the outside temperature,” said Alex Burney, the company’s chief executive. “That’s the path to energy independence.”
The filters, which can be applied to any window at the time it’s made, add about 20 percent to the cost. In September, RavenBrick hopes to introduce a filter that can be added to the exterior of an already installed window.
The company recently received 54 patents for the technology, which will be one of two window technologies used in the National Renewable Energy Laboratory’s 222,000-square-foot Research Support Facilities building under construction in Golden.
The RavenBrick technology responds automatically to the outside temperature. The other technology, by Sage Electrochromics Inc., is controlled by the user.
“We’re really excited to see how people in the building will respond,” said Erin Whitney, dynamic window-durability-testing coordinator at NREL. “They’re two very viable technologies, and we’re all interested to see how they work.”
RavenBrick plans to introduce an insulation system next year. By storing energy in recycled corn waste within a building’s walls, RavenSkin can delay solar-heat gain from the afternoon, when it’s least desirable, to night, when it’s most helpful. This helps regulate the internal temperatures of buildings — even off-grid buildings with no heating or cooling system.
Burney and partners Wil McCarthy and Rich Powers, both University of Colorado graduates, raised $3.5 million in startup capital, mainly from local angel investors.
Burney is responsible for business development, operations, marketing and financing.
McCarthy, the company’s president, is responsible for research and development, maintaining the company’s intellectual property portfolio and managing partner relationships. Powers is vice president of research and development and leads the company’s scientist team.
Margaret Jackson: 303-954-1473 or mjackson@denverpost.com