by Shane Henson — July 15, 2013—Even century-old buildings can become energy-saving powerhouses through the installation of new technology and systems, as demonstrated by Net Zero Impact LLC, which recently completed an installation of its largest hybrid solar-thermal system to date at Addison on Fourth near Seattle, Washington’s International District.
The building, originally constructed as a hotel in 1911, has been renovated by Goodman Real Estate. The renovation is focused on development of a “green,” economically viable, highly efficient mixed-use facility. Replacing steam-generated heat provided by Seattle Steam, Net Zero Impact’s hybrid solar system—including solar-thermal tubes, high-efficiency boilers and automated system controllers—will dramatically increase the building’s overall energy efficiency, even during Seattle’s cool, cloudy winters, the company says.
The expected savings on energy costs are estimated at $60,000 per year, nearly a two-thirds reduction. With available federal tax credits and local grants, Goodman Real Estate expects to recoup its solar investment within three years.
Sun-generated steam from 450 Net Zero Impact solar-thermal tubes reaches a temperature of 212 degrees, pre-heating water for two new boilers that deliver heat to existing radiators throughout the structure. Solar-heated water, at a temperature of approximately 120 degrees, will also be piped throughout the building for domestic use.
In addition to the rooftop solar tubes, the following equipment and renovations were part of the Net Zero Impact’s project:
- Two 98 percent, high-efficiency domestic hot water boilers
- Automated electronic controllers to manage the entire heating system
- A complete rebuild of the condensation system for existing radiators
- Installation of hot water tanks, piping, pumps and new gas lines
- A complete exhaust system upgrade
- New temperature valves for the century-old radiators
Net Zero Impact designs and installs hybrid solar technologies for commercial applications in the Pacific Northwest. According to the company, its hybrid solar-thermal system will prevent 275 metric tons of carbon dioxide from entering the atmosphere, roughly the equivalent of greenhouse gases emitted by 54 cars.
