Soleil Lofts' virtual power plant: What you need to know

In August 2019, the solar and storage industries took a giant leap forward with the introduction of the Soleil Lofts virtual power plant project. The apartment complex, which lies just south of Salt Lake City, Utah, is a unique, first-of-its-kind collaboration between a building developer, an energy storage company, a major utility, and a local solar installation company. To learn how the Soleil Lofts project came together and to get a feel for the lessons learned during the process, EnergySage sat down with Jess Phillips, the CEO, and founder of Auric Energy, the solar and energy storage developer responsible for the project.

In Salt Lake City, there's a large air pollution problem as a result of the geography of the region. The same inversion that helps propel blue-bird days in the ski mountains a short drive from downtown ultimately envelops the valley the city sits in, trapping air pollution from all sorts of industrial processes–including electricity generation. At the same time, the city's population is increasing as more companies are moving to the area and drawing new workers.

A shortage of housing options and increasing air pollution presented a question and an opportunity: how do you build additional space to meet the housing demand without placing additional stress on the energy grid and, as a result, exacerbating the existing air pollution issues in the region?

This is where the idea for the Soleil Lofts came together: the goal was to create an off-grid community capable of meeting as much of its own electrical needs as possible with renewable energy produced onsite. While this type of development had been pioneered at the neighborhood level in Europe and was under development in parts of the US (such as a project in Arizona), the Soleil Lofts development promised to bring solar-plus-storage technology to apartment development, offering an opportunity for renters to benefit from solar directly.

The resulting properties are truly impressive: the project consists of 5.3 megawatts (MW) of solar capacity across over 12,000 solar panels, 12.8 MW of energy storage capacity, including batteries in each of the 600 apartments, 150 electric vehicle car chargers, and 73 solar carport structures. The apartments are all-electric (i.e., no gas is needed for heating or cooking), and the solar panels can generate enough power to cover 80 percent of the development's electrical needs.

Residents moving in receive the benefits of solar in a couple of key ways. Importantly, their electric utility bills should be 10-20 percent less than if they lived in non-solar-powered apartments of a similar size. Next, they can participate in the solar industry flexibly, not needing to invest the cash upfront to install a system on their property and without needing to find a new subscriber for a community solar-type commitment if they move. And, finally, with the energy storage systems in the heart of their apartment, residents of Soleil Lofts can feel connected to the renewable energy transition every day, watching the battery recharge from the sun or hearing it hum as it kicks on to provide power when needed.

In fact, according to Auric Energy, these factors have combined to mean that the people renting from the Soleil Lofts are "regular, everyday people that just want to do something about the climate change issue." Initial signs indicate that the opportunity to contribute to the solution for the same cost as living elsewhere is a very large selling point.

Auric Energy is very well-versed in the solar industry. Based in Salt Lake City and with regional offices in five cities, Auric Energy employs 230 people installing both residential and commercial systems nationwide. As of 2019, the company has installed over 7,000 residential systems and nearly 200 commercial systems over ten years in business.

A large part of what made the Soleil Lofts project work is Auric Energy's pre-existing relationship with Utah real estate developer Dell Loy Hansen, Founder and CEO of Wasatch Commercial Properties and owner of Real Salt Lake, with whom Auric previously partnered to install solar on the training facilities of the local Major League Soccer team.

From there, the question became which solar equipment to install at the Soleil Lofts. For the solar panels, Auric worked with Solaria, who designed a custom, high-powered 430-watt panel for this apartment complex. An equally, if not more, important partnership is required to determine which energy storage manufacturer to work with. Given that the developers decided to install individual batteries in each apartment, as opposed to building one larger centralized storage system, the choice of partner was vital to the success and livability of the apartments.

Ultimately, Auric decided to install sonnen batteries, providing an ecoLinx 20 kW battery in each of the 600 apartments. The decision came down to three key factors: sonnen's safety record, the ability of the ecoLinx battery to cycle every day for a long period, and the battery's aesthetics, as it is an ever-present component in people's living rooms. Beyond that, sonnen brought their expertise from developing similar projects overseas and a willingness to collaborate closely on the project by, for instance, tweaking their battery design to include a special fan recognizing the heat and sound concerns that arise with installing batteries in living rooms.

The most important lesson to be learned from the Soleil Lofts development from Auric Energy's perspective is the fact that this was a collaborative effort that benefited everyone involved. The local utility, Rocky Mountain Power (RMP), entered the project's development as eager partners. Rather than begrudgingly compromising to allow this project to proceed, RMP committed funds to aid development and implicitly expressed their interest in building more of these projects.

At the same time, it's important to note that projects like the Soleil Lofts don't come together without vision and persistence. Developers nationwide can now see that an all-electric, self-powered apartment complex is possible and take the next steps to design their own project in their area.

Part of the allure of solar is that the technology allows any individual property owner to become a power producer. Once you add energy storage to the equation, anybody with a solar-plus-storage system can now function as a miniature power plant: creating electricity and, with the help of storage, calling on that electricity exactly when it's needed to power the home. You can effectively create a decentralized power plant when you aggregate multiple solar-plus-storage systems and allow them to work together. Recently, this type of project has been dubbed a "virtual power plant."

The Soleil Lofts project is a perfect example of how the solar industry could continue to evolve into the future: the development is designed explicitly with the ability to power itself in mind, with the goal from the outset to be able to rely as much as possible on locally produced solar energy instead of fossil-fuel fired generation from hundreds of miles away.

However, virtual power plants don't need to be limited to new construction developments. Instead, with smart, coordinated planning, most communities in the US could turn into their own clean power producers, balancing local supply and demand and providing solar power freely and efficiently throughout the neighborhood.

While the Soleil Lofts are unique in their scale, scope, and vision, the opportunity to power your life with solar is not limited to a select few. Solar is more accessible than ever, thanks to great incentives and declining costs. To see how much you could save by powering your home with solar, check out the EnergySage Solar Calculator or register for a free account on the EnergySage Marketplace to receive custom solar quotes from companies near you.