Potential for net-zero building
By Cayla Vidmar
The Gunnison County courthouse could be getting close to net-zero energy use, with the addition of a possible solar photovoltaic panel project on the building. Johnson Controls, Inc., the company hired by the county for the energy performance evaluation contract, submitted an overview of the process and energy performance opportunities.
The big picture the county is trying to accomplish with this upcoming energy performance contract, according to the Gunnison County Sustainable Operations director, John Cattles, is to put photovoltaic units on a number of county buildings, and renovate the heating and lighting system at the Blackstock building.
Cattles said that through previous energy performance contracts, the county has been able to lower the energy use at the county courthouse and the human services building significantly, giving the county the opportunity to generate onsite energy using photovoltaic panels. The county courthouse, Cattles says, uses half of the site energy of the average LEED (Leadership in Energy and Environmental Design) platinum-designed building, “so it’s very, very good.”
However, despite a very energy-efficient courthouse, Cattles explains that the building’s source energy, which is all-electric, increases the building’s greenhouse gas emissions. “Our electric grid is relatively dirty. So you can have a really efficient building, but since we’re using electricity to power this building and the human services building, the greenhouse gas impact is out of line with our energy use,” says Cattles.
“This is an opportunity to take our actual energy use on site and actually match, or bring it closer to our source energy use, so our actual impact on the environment will be much lower by generating energy on site,” says Cattles. Gunnison County manager Matthew Birnie said this plan has been contemplated since the county undertook the energy performance projects, and the buildings were planned with the assumption that photovoltaic panels would be added later.
The intention for the photovoltaic system on the county court house is to meet the daytime demands of the building, and not overproduce energy to be put back into the electrical grid.
Cattles notes, “Early estimates show the system will pay off in the lifespan of the system, within 25 to 30 years.”
Johnson Controls, Inc. account executive Rowena Adams explained a broad overview of what the next few months would entail for the county regarding the energy performance audit, in which the company would identify energy improvement opportunities, conduct engineering design for those opportunities, and work with the county to release a financing request for proposal. Adams explained that at the end of July, the county would undergo a “scenario workshop, where it all comes together—we show you all the numbers, and you pick improvement measures you want to implement.”
Johnson Controls, Inc will begin conducting detailed inspections and audits of county buildings, as well as begin to develop conceptual improvement scenarios.