The Green Button, a White House initiative that was first championed by a few utilities and vendors in California and Texas, is quickly gathering support across the nation.

On Wednesday, the Green Button initiative announced a new round of participants, including energy management and efficiency companies Retroficiency, EnergyAi, Performance Systems Development, Snugg Home, Wattvision and Melon Power, as well as more large utilities.

The latest additions show that the Green Button holds appeal for all utility customers, and commercial customers in particular. Retroficiency took a year’s worth of Green Button data for a commercial building and using its virtual energy assessment found that the building could reduce consumption by one-third through a variety of retrofits.

“Broadly adopted standards like Green Button that enable straightforward, secure access to granular energy interval data from the utility is a key piece of the puzzle to bringing scale to energy efficiency,” said Bennett Fisher, CEO of Retroficiency, “Green Button has the potential to make it that much easier for Retroficiency to use this data to identify energy savings opportunities in buildings and rapidly deliver recommendations to customers.”

Other companies, such as EnergyAi, are also providing data on usage and where money can be saved. For one office building, EnergyAi’s app found that leaving equipment on at night and over the weekends was costing an extra $9,000 per year. EnergyAi is one of the companies that has already developed an app leveraging Green Button data.

Indeed, app development that leverages Green Button data is perhaps the most important part of this initiative. The U.S. Department of Energy is running an apps competition that comes with $100,000 in prizes to software developers for the best new apps to help utility customers make the most of their Green Button data. Submissions are open until May 15 and the winners will be announced May 22. The largest prize of $30,000 will go to the grand prize for best overall application.

The DOE also recently launched the Utility Data Access Map tool, which shows customers the data they can access about their electricity use. Sadly, the current map is mostly white, indicating that customers do not have access to data. However, it’s still early days, and although the DOE has responses from more than 500 utilities, data is lacking from many of the largest utilities. If successful, it provides a nice snapshot of which regions are allowing customers to share their data with third-party providers, if they so choose.

Utilities will likely sign up for the map, since they are signing up in droves for the Green Button. On Wednesday, PPL Electric also joined the White House’s Green Button initiative. The Pennsylvania utility has 1.4 million smart meters in place. National Grid, TXU Energy, Chattanooga EPB and PacifiCorp, which includes Rocky Mountain Power and Pacific Power, also signed on to the initiative. That brings an additional seven million customers into the Green Button, bringing the total to more than 30 million homes and businesses.

For utilities and companies that are looking to the future, the question by 2013 could still be ‘Who is using Green Button?' -- but instead, by that time, we’ll likely be asking why some companies are holding out.