Solar panels are a great resource for homeowners – when the sun's shining.
Demand response – turning down household loads like air conditioners and appliances – is a great resource for utilities when they're facing peak loads on their electricity grids.
Why not tie the two together? That way, household appliances could run on household solar power when the sun's shining, then power down when passing clouds cut that solar power. That could give utilities a new tool to manage the uncertainties surrounding lots of grid-connected rooftop solar systems that they now can't control.
Home energy management startup Tendril Networks has teamed up with renewable power management startup Fat Spaniel Technologies to bring these kinds of functions to the home.
The idea is to create a "utility-facing solution for residential energy management incorporating data and analytics from renewable energy sources," according to Fat Spaniel's announcement this week at the Solar Power International conference in Anaheim, Calif.
Distributed generation – as opposed to utility-scale wind farms and solar power plants – usually means rooftop solar panels. How to manage that growing amount of customer-owned power is a matter of some concern to utilities in solar-rich states such as California.
In fact, some of the roughly 30 utilities that are piloting Tendril's home energy management devices and management software have been asking the Boulder, Colo.-based company for help in managing those rooftop solar systems for some time, CEO Adrian Tuck said this week (see Tendril Wants to Link to Solar Panels).
"Specifically," he said, utilities have asked Tendril to "create programs so that devices in the homes could react to the PV," he said.
The first reason would be to lower the amount of electricity a house needs, which will reduce the size, and thus the cost, of a home solar system, he said – the same reason utilities suggest homeowners do energy efficiency audits before buying solar panels.
But beyond that, integrating solar panels and household loads could help balance out the intermittent nature of solar power, Tuck said.
Take the challenge utilities in hot climates face in delivering power on hot summer afternoons, when air conditioners make up a sizable portion of their peak loads. Solar panels tend to be a pretty good resource for those situations, since they tend to produce most of their power on sunny afternoons.
But passing clouds can shift those homes from an energy generation resource to a utility load in a matter of minutes. Having each house help balance that shift on its own could be a simpler matter than asking the utility to set up independent systems to monitor rooftop solar panels and manage in-home demand response.
Of course, only a tiny fraction of homes now have solar panels, but that number is expected to grow as solar panels continue to fall in price.
Tendril is also working to integrate its energy management systems with General Electric's upcoming home energy management systems and smart devices (see GE, Tendril Team Up on Smart Home Technology).
GE has discussed bringing "net zero energy homes" to market by 2015, and being able to link rooftop solar, batteries or other forms of energy storage, and household energy management would help make them more efficient (see GE Unveils Net Zero Energy Home Strategy).
Fat Spaniel, for its part, isn't just looking at household solar, but also wants to help monitor and manage utility-scale solar power plants (see Fat Spaniel Moves Into Power Project Development Biz).
A host of companies, including Energy Recommerce (ERI), SolarEdge Technologies, Tigo Energy and eIQ Energy, are seeking to provide utilities more information to help better manage solar and wind power, though most are concentrating on larger-scale systems (see National Semi Buys Energy Recommerce and SolarEdge Lines Up GE As Investor).