If Sunverge is right, more will be less.
The company -- which recently came out of stealth mode -- is coming to market with a combination solar array/battery pack/smart grid gateway that it says will reduce the overall cost of renewable power, particularly once time-of-use pricing arrives.
It works like this: instead of installing a 4-kilowatt residential solar system on your roof, Sunverge or one of its partners will install a 2-kilowatt system along with an 8.8-kilowatt-hour lithium ion battery pack and gateway that lets a utility monitor the panels and the battery pack.
The 2-kilowatt with battery system costs about the same as the standard 4kw system, but it will result in 20 percent to 30 percent lower electricity bills in time-of-use regions, according to president and co-founder Kenneth Munson. The solar panels would bank power in the morning, when consumers aren’t home to use it, and let them use it during peak power hours. Put another way: instead of consumers selling power to the grid and buying it back in the afternoon or night every day, consumers shift more of their time off-grid.
The discount would also be achieved by additional fees paid by utilities to exploit the battery pack for grid balancing and demand response applications. Potentially, if you could put enough batteries in a region, a utility could delay upgrades or other capital expenses. (That's the battery pack and distribution equipment in the photo.)
EV charging? If consumers can tap into their stored solar energy, scheduling charging in the neighborhood becomes less worrisome.
“The more we can use power on site, the safer the grid becomes,” said CEO Dean Sanders, the other co-founder. “The business does depend on a variable rate pricing structure.”
Peak power pricing is somewhat rare right now, particularly when it comes to residential electricity, but many expect utilities to promote it once their smart meter infrastructure gets put in place.
The company is in the midst of setting up a pilot involving 34 homes in the Sacramento area. It has signed contracts to integrate its technology in five multifamily housing projects in San Diego and landed two other deals in northern California: one for a multifamily project and another to equip a 300-home subdivision with battery packs, gateways and solar panels.
Overall, Sunverge has contracts to install 40 megawatts of solar and 150 megawatt-hours' worth of battery packs.
The company is part of a growing wave of outfits that want to better tie smart grid functionality to solar and, perhaps more importantly, to leverage smart grid technology and storage to lower the cost of solar. Petra Solar has devised a solar panel with an integrated smart grid monitoring system that fits on a utility pole. The utility poles, in aggregate, then act as a distributed power plant.
Sanyo, meanwhile, will combine solar and batteries. Ideally, demand response fees or other incentives will provide a quicker and recurring payoff for consumers, according to Arturo Zarate in Sanyo's new business development and marketing group.
At the other end of the spectrum, Xtreme Power, which makes a fiberglass dry cell battery for power plants, installs battery packs at solar and wind farms. The battery packs allow the power provider to store and dispatch electricity more efficiently than normal, says CEO Carlos Coe. At the same time, the revenue stream from leasing storage capacity on its packs can become a second profit stream.
Tim Simon of the California Energy Commission at an event last week sponsored by Alston + Bird suggested that storage might become a more standard component of renewable power plants. One idea: requiring new solar and wind farms to install a minimum amount of battery capacity as a short-term solution to smooth any potential imbalances caused by increasing the percentage of renewables on the grid.
“If we don’t put something in [for storage], renewables will be more expensive,” Simon said.
Conversely, demand response providers are examining virtual storage. EnerNoc, which will take unwanted power surges from solar and wind farms and shift it to cold storage units, i.e., meat lockers. Dropping the temperature inside meat lockers balances the grid, makes use of excess power -- and the pork chops don't care.
Like Petra, Sunverge’s core intellectual property is found in the communications and monitoring technology for the grid. The batteries and actual solar panels come from third-party providers. Sunverge’s technology came out of Inertia Engineering, which has been producing switches and distribution automation equipment since the mid-1990s. It sells equipment under its own brand in the western U.S. In the east, giant ABB sells the equipment under its brand.
Sunverge likely won’t sell these systems directly to consumers. Instead, power providers or utilities will try to erect systems en masse on residential and commercial rooftops. A power provider can more easily negotiate fee agreements for accessing residential battery packs. At the same time, the utilities can get a more comprehensive view of the amount of storage and solar being added in a particular region.
Like the rest of the solar world, Sunverge will sell equipment, but quite a number of its installations will be erected under lease plans.
Warranties? It’s an issue. Solar panels last 25 years and longer. Battery packs will only go 15 to 20 years, said Sanders. Still, it’s a somewhat comfortable environment for batteries, with moderate charge/discharge cycles and easy ambient temperatures. Sunverge opts for lithum phosphate batteries and is amenable to most other lithium chemistries except for the exciteable lithium cobalt variety.
The battery packs qualify for federal and state credits, Munson added.
But what if the price of solar drops faster than batteries? The integrated solution would provide additional benefits that utilities would likely pay for. Solar price declines have also slowed down. Batteries, however, could spike with EVs. And just ask thin film startups: you can’t take anything for granted when it comes to silicon.
Still, this should be one of the interesting trends to watch.