Cool Tool: Visualize a Decade of Solar Progress

(MoneyWatch)  In covering the solar industry, it's easy to get caught up in facts and figures about the total size of the market -- specifically, its relatively tiny size; solar still accounts for less than half a percent of our total energy generation. The view on the ground is a bit different -- or on the hilltop, where one can see how many homes actually have solar on their roofs.

With the aim of helping people form an accurate view of the solar panel industry in the United States, the National Renewable Energy Laboratory has been quietly building data and attaching it to a suite of visualization tools, calling it the Open PV Project. And despite having written about solar for a few years, I've learned a fair amount just by playing around on the PV Project site for a bit.

For instance, who knew that Montana and Wyoming have a decent number of solar installations, and that those were installed earlier than in most other states? Check out the PV Project's progressive heat map, and you'll see dots popping up across the two states early in the last decade, followed by another burst later as neighboring Colorado becomes a significant state for solar.

Most states have some amount of solar, although California takes the title as the biggest market by far, accounting for 51,260 installations out of a total 67,370 that the PV Project has tracked. That's over 75 percent of the total. But in the site's visualization index you'll find that the disparity is pretty intense between the remaining 49 states.

There are seven, in fact, for which the PV Project hasn't logged a single installation: Alaska, Arkansas, Kansas, Kentucky, Nebraska, Oklahoma, and both of the Dakotas. There probably are a few solar panels in those states, but the point of the map is simply to show the relative amount of solar in different areas. It gets the point across: the above states show up as a huge empty streak splitting the country in half.

The PV Project, which seems to be based on data submitted by volunteers, also shows itself to be pretty accurate when compared to analyst's reports. It records an average cost per watt of $8.01 in 2009, significantly lower than the $10 or so per watt people were paying a few years before. Also revealed, though, is that the price is still high in some states, including solar-friendly New York.

Check it out yourself. As renewable energy grows up, this is exactly the sort of data we need. The government can use it for planning subsidies and support; solar installers will increasingly need insight into potential new markets. And for everyone else, the PV Project just provides proof: yes, solar really is growing.