Sol Lux Alpha Creates First Net-Positive "Nanogrid" Condominium Building in United States

April 20, 2018

San Francisco, Sol Lux Alpha, Passive House Certified, Off the Grid Design, Passive House Institute Standards, Living Building Challenge, Zero Net Energy Challenge, SunPreme, Tesla Powerwalls, Front Facade

By Meghan Hall

685 Florida Street in San Francisco is now home to the nation’s first positive net-energy "Nanogrid" condominium complex to be brought to the Real Estate market. Called Sol Lux Alpha, the six-story, four-unit development was just completed and accredited as Passive House Certified in April 2018.

Conceived and developed by Off the Grid Design, and Klein Limited Partners, the condominiums meet Passive House Institute Standards, which originated in Germany. According to Off the Grid’s CEO John Sarter, the team was inspired to bring the concept to the United States after seeing it work in other locations around the world. When speaking about why Off the Grid Design chose Passive House over other standards, Sarter said there were many options to choose from, including LEED, the Living Building Challenge and Zero Net Energy Challenge. While many of these standards focus on the quality of construction, few, according to Sarter, focus on trying to completely eliminate greenhouse gas emissions.

“I’ve been designing and building for 32 years, but in that time I haven’t found a metric and methodology that really focuses on reduction of energy use as much as Passive House does,” he explained. “Sustainable building standards are great, but really in my mind our energy use is probably the biggest issue of our time and that’s where we need to focus.”

Passive House is a metric that specifies how a building utilizes a total source of energy over each square foot of space. The ultimate goal is to regulate energy output by carefully utilizing highly insulated walls, eliminating "thermal bridges" and creating effective ventilation systems to create a more airtight and therefore more energy efficient building and greater occupant comfort and health.

Although the standard was established in the 1990s, Sarter believes that there is no better time than now to introduce net-positive housing into the market, since technology has advanced and more and more people are pushing for sustainable modes of construction. However, the process didn’t come without its challenges. Sol Lux Alpha was originally slated to be completed last year, but was instead just completed this spring.

“We don’t rush through things just because there’s a faster way to do it, we focus on quality over quantity”, said Sarter. "Development in SF is also booming now and it's difficult to get your subcontractors to meet scheduling."

However, Sarter does believe that the delays and the extra time it took to complete the project were absolutely worth it. Construction stalled not only because the team was using technology that the City of San Francisco had not previously approved, but also because the cutting-edge technology the team sought was rapidly changing.

Sol Lux Alpha ESS - 24 kWh Blue Planet Energy "Blue Ion" towers on left and 162 kWh TESLA Powerwalls on right

“Technology was advancing so quickly that we changed battery vendors three times over the course of the project,” said Sarter. "We ended up with 2 excellent Energy Storage partners in Blue Planet Energy from Hawaii, and Tesla Energy. Had we finished any sooner, we would not have had Tesla as a project Partner."

The complex features all the bells and whistles of a typical development such as high end finishes and a rooftop deck and garden, but the development’s innovative energy-saving technology is an amenity all on its own due to its functionality and design.

The roof, for example, is home to SunPreme bi-facial solar panels which absorb sunlight both directly and from reflective surfaces in the surrounding neighborhood. And, because each panel can absorb sunlight through its top and bottom, extra energy is generated.

“Those photo cells collect light from the surrounding neighborhood and they can produce up to 25 or 30 percent extra energy generation,” explained Sarter. “The PV trellis is over our roof deck and lets in filtered light too, so it’s also a really nice design element.”

The complex also includes 12 Tesla Powerwalls. Each condo unit has three of these power-packed integrated units, which can power an entire unit for up to two or three days, depending on occupant behavior. Electric vehicle charger-ready parking, LED lighting, Bosch appliances and vampire load reducing outlets were also added in order to minimize power use. Any excess power generated can be sold back to the grid or used for EV driving, so homeowners are able to develop revenue from their homes.

“It's designed so you may never have an energy bill here, other than minimum fees” said Sarter. “The resilience this kind of building creates is a luxury that is new to the real estate market.”

All units have not been officially priced out yet, but the first was intentionally priced and released on "Earth Day". Sarter does believe, however, that the units will sell quickly as they are the only four of this kind in the USA, for now.

“The societal value of what we’ve done here is something you can’t really put a price on,” said Sarter. “It’ll be interesting to see how the public receives that.”