The first residents of an all-electric and energy-efficient community — the largest residential battery demand response project in the United States — are settling into new apartments. Their cars are tucked neatly beneath solar panel covers and their electric cars can plug into charging ports. Inside each apartment in the Soleil Lofts development, a Sonnen battery is humming silently close to their living room.
The residents sign on knowing their backup power can be controlled by the utility and dispatched to the grid as needed. The circular logo on the Sonnen system will turn green to tell residents when the battery’s power is being used by the local utility, Rocky Mountain Power.
The full complex will be finished in the next two years, but the virtual power plant established when the first building opened is a blueprint for developments outside of Utah, according to the real estate developer Wasatch Group.
The Soleil Lofts apartments, under construction in Herriman, Utah, seeks to attract environmentally conscious customers who want to hasten the transition to all-electric and clean energy living. The project represents a collaboration among Rocky Mountain Power, battery developer Sonnen, solar developer Auric Energy and Wasatch. All the partners have plans for modelling the success of the Soleil projects.
The effort is an opportunity for the Pacificorp subsidiary to work with a partner that has experience with energy storage, as the utility learns to better integrate batteries into the grid and enable growth from renewables, according to Bill Comeau, Rocky Mountain Power’s managing director of customer innovations.
When complete, the planned community’s 22 buildings will have 600 apartment units with 12.6 MWh of battery storage, 5.2 MW of solar panels, 150 stalls of EV chargers and an overriding focus on energy efficiency. Utility access to the 600 Sonnen batteries will turn the complex into a grid resource.
“In the big scheme of things, it’s actually really small,” Comeau told Utility Dive. “But the long term thing for us is how do we provide battery solutions for our customers?”
The Soleil Lofts development is one of several grid modernization efforts regulators have approved from Rocky Mountain Power in Utah. The utility is partially funding the energy storage systems although they will be behind-the-meter resources owned by Wasatch.
“As a utility, we’re 100% controlling the batteries for the greater good of the grid,” Comeau said. “And then we’re just trying to figure out how we can scale that to provide more options for customers.”
The utility joined the collaboration following growing consumer demand for distributed energy resources. According to Comeau, customers have been asking for rooftop solar for the past five years, but they have more recently started asking for energy storage as well.
Customers often ask the utility directly for distributed solar power, he said, making the utility a natural partner in this project. However, distributed energy developers and installers continue to promote a variety of partnerships, including without direct involvement from the utility.
”In Utah, the value proposition is very strong here” to partner solar with other developers, like roofing and HVAC professionals, Complete Solar’s Dave Anderson said.
“When utilities are offering solar, I think that’s great,” Anderson said. “Maybe the only issue with utilities offering solar products is that again, you’re limiting the market innovation that can happen, in terms of figuring out the best, least expensive most efficient way to get power to any given consumer.”
Like other projects where distributed resources are operated by utilities, individual systems reserve a set amount of power to ensure the complex can be powered in case of a grid event. For example, Hawaiian Electric will have access to aggregated power from Sunrun’s solar-plus-storage systems across Oahu, but will only call on individual systems for 30 minutes at a time.