US firms help solar homes track energy

By SmartPlanet on 16 October 2008, 11:30am

Two very different US companies are developing ways to track energy usage in homes equipped with solar panels. SolarCity, a company that leases solar panels to households, introduced a new version of its SolarGuard software this week to display panels' production alongside a home's electricity usage.

In many US states, people pay a higher rate for electricity during peak times in the middle of the day and early evening. By tracking usage -- and solar panels' production -- people can decide to run a washing machine at night, for example.

"The biggest energy-efficiency challenge in every house is not changing light bulbs. It's changing behavior," SolarCity CEO Lyndon Rive said.

California-based SolarCity, like other solar installers, uses its Web monitoring system to ensure that there isn't a drop in panels' performance. Consumers get access to the energy usage application as part of their leasing program, Rive said.

SolarCity's Web monitoring software tracks both solar panel production and household energy usage.

Meanwhile, Open Energy, another Californian solar panel maker, is in the midst of developing a dedicated touch-screen device for tracking solar panel and home energy usage.

There are already in-home displays that show a home's energy usage at a given moment. But most of them simply display the electricity meter and can't show whether a home's panels are producing more electricity than the home is using at a given moment.

Open Energy's device, which has a wireless Zigbee connection to an Internet gateway, can show solar panel production alongside electricity usage. It can also pull in gas and water usage, said company product manager Mark Bettis.

The product is set to be released next year and will cost between $1,100 and $1,400, which includes five years of solar panel monitoring.

"People need to know whether they are getting their money's worth out of the solar panels," he said.

On Wednesday 15 October, Open Energy also introduced a roofing tile with a solar cell embedded in it.

The companies made their announcements at this week's Solar Power International conference.