Xcel anticipates selecting six Stapleton homeowners for participation in a two-year test of current battery technologies at homes that already use solar power. Xcel held a public open house in November to solicit interest in having refrigerator-sized units installed “behind the meter.” The units, which cost $15-$20,000 each, would be provided to consumers free of cost as Xcel studies alternative battery technologies, the integration of distributed storage to help even out load demand for the utility, and how Xcel can accommodate more solar energy into its system. About 50 Stapleton residents attended the open house. Participants would benefit by having additional battery storage that could provide the home with electrical power during a system outage.
Participants will be announced in February. The in-home batteries would go live in March.
Xcel is targeting the residential neighborhood north of Martin Luther King Blvd., between Trenton and Havana Streets. Xcel representatives said this is one of the neighborhoods with the highest penetration of home-based solar panels in its service territory. At the open house, Beth Chacon, Xcel Energy’s director of Grid Storage and Emerging Technologies, said “Xcel wants to learn how energy storage can help manage the impact of high concentrations of rooftop solar energy on distribution system feeders.” Distribution feeders are used to bring electricity into homes and businesses and carry the energy produced by in-home solar systems to the electric grid.
Chacon said the North Central Park and Eastbridge neighborhoods have about 20 percent penetration and that 35 percent represents a “tipping point” in terms of impacts on the grid. Voltage issues, sometimes perceived as “light flickers,” can begin to impact the grid as power flows back and forth between the homes’ photovoltaic systems and the grid.
Xcel also hopes to announce in February the location of six utility scale batteries to be installed along the utility feeder line itself in this neighborhood. These batteries “in front of the meter” would be placed at various locations within the public street right-of-way.
This pilot project is one of two approved in March 2016 by the Colorado Public Utilities Commission (PUC) under the company’s Innovative Clean Technology (ICT) Program.