Google Inc. (NASDAQ: GOOG) on Tuesday launched a new prototype software to measure home energy use, and threw its weight behind getting utilities to open up that energy data to customers and third party developers like itself.

Google's new PowerMeter iGoogle gadget isn't available to the public yet, though curious people can check out a demo and hear from Google employees who say they've saved big on their power bills by using it.

Nor does Google have utilities or power monitoring equipment makers lined up yet to supply data to PowerMeter, though it's actively looking for partners.

As part of that effort, the search giant is asking the California Public Utilities Commission to make electricity data "available in a standardized, open format, freely available to third-parties with permission from the consumer" – another shot across the bow of a "smart grid" industry grappling with how to manage data on how millions of customers use energy.

Tracking and adjusting energy use can help homeowners save 10 percent or more on their power bills – a statistic quoted often by makers of home energy monitoring and control equipment and software like Tendril Networks, Greenbox, Gridpoint, Control4 and others involved in pilot projects with utilities (see Sensus and 4Home Look Toward Home Area Networking and Tendril Expands Its Reach in Smart Homes).

But all that hardware and software needs data to be useful -- and for now, it's likely that most of that data will come from the millions of smart meters now being installed by utilities across the country (see Smart Meter Installations Grow Nearly Fivefold and SCE Preps $1.63B Smart-Meter Program).

The Obama administration has called for 40 million smart meters to be installed in American homes as part of its economic stimulus proposal, and current versions of the stimulus bill include $32 billion for improving the nation's transmission grid, $4.5 billion of it dedicated to grants for smart grid-related projects (see Draft Stimulus Plan Has Billions for Smart Grid).

So, while other options for collecting and distributing home energy data may emerge (see A Broadband Smart Grid?), right now smart meters are at the heart of pilot projects that enlist customers in energy-saving measures like demand response programs (see Smart Grid Test: Customers Give Thumbs Up and Tendril Targets Meter Makers).

And Google's call to regulators to get utilities to open that data to third parties could play into an ongoing industry debate over open standards for smart meter data communications (see Smart Grid: A Matter of Standards and Traditional Meter Makers Say Stimulus Favors New Smart Grid Companies).

"Our tool is free and scalable, and we plan to release the technical specifications (application programming interfaces or API) so anyone can build applications from it," Google told the CPUC.

And Google wants everyone else in the smart meter business, utilities included, to be equally as open, as long as customers have the power to keep their own data private if they so choose.

Google has been pushing its name into smart grid lately. It joined the smart grid trade group Demand Response and Smart Grid Coalition in November, and in September it said it would work with General Electric Co. (NYSE: GE) on renewable energy and smart grid technologies (see Google and GE Gang Up for Green Energy).

That's part of an overall energy platform that includes about $45 million in renewable energy investments by its philanthropic arm, Google.org, and a call for a $4.4 trillion national energy policy heavy on replacing coal-fired power plants with renewable energy sources, which would need lots of new "smart" transmission.

All that has led Ron Ambrosio, global research leader for IBM's Energy & Utilities business, to cite Google as a natural competitor – and potential partner – in the smart grid industry (see IBM, EDF to Research Smart Grid Tech).