U.S. Has 100,000 Grid-Tied PV Systems - Happy Valentines Day!**

**July 2010 update at end of blog

I am a self-confessed data junky when it comes to PV installations. And my favorite metric for following a PV market is the number of installations, rather than the capacity of MW installed. Perhaps I favor distributed generation over centralized, or maybe it seems like the more systems installed, the more jobs created.

Our country is now, very likely, hosting more than 100,000 grid-tied PV systems. Quite a milestone.*(see comments below). The last data milestone this exciting was when we hit our first cumulative Gigawatt of grid-tied PV capacity, sometime last year. That went mostly unreported, but based on Larry Sherwood's "Annual Trends" report we may reach the 1GW per year milestone in 2010. In any case, we are now past our first "onesies." One Gigawatt, and One-Hundred-Thousand distributed systems.

About the Data

The largest number, from California, is based on adding 15% to current California Solar Initiative (CSI) projects to account for the non-IOU installations. 15% may be optimistic, but it is in line with what was happening in 2008.

Here are the details behind my estimates. The lovely underlying map is from the Open PV project. For links to the original reports and press releases visit SolarInstallData.com, where I try to drop all the data resources I find.

[apologies for the formatting]

Total: 97,475

There must be more systems out there unreported. Let's get them counted!

Excellent resources for tracking the number and capacity of grid-tied PV systems include Larry Sherwood, and his annual market update reports supported by IREC. More recently, the Open PV project from NREL has been compiling actual installation data from utilities, installers, and individuals. I am told by Brendan Heberton from NREL's Open PV project that a system doesn't make it into their database unless they have the size, location, cost, and installation date. This is a pretty high bar so the Open PV project is still recruting confirmations from much of the U.S. market. The sales and costs data they are recruiting is going to make a big difference for emerging markets across the U.S.

Then there is the grandaddy PV database, CaliforniaSolarStatistics.ca.gov. While thre are still plenty of errors and glitches, it is still missing the first 33,000 systems installed in the state (under the previous incentive program), and there is no way to confirm contract price accuracy - the CSI database is the best thing since sliced bread for consumers, regulators, and installers for tracking what is happening in the PV market.

If you are in a state that seems to be missing a few thousand systems, please help the Open PV project get them reported. If you know of installation reports and data resources not already listed at SolarInstallData.com, email me and we'll get them on there.

Go Solar!

** July 20, 2010 UPDATE: Through an IREC market update Larry Sherwood confirmed today that the U.S. passed the 100,000 grid tied PV system in 2009.See his data and charts through reports posted at http://www.irecusa.org.

Liz Merry owns Verve Solar Consulting, through which she teaches (The Business of Solar (tm) and Solar Careers and Opportunities (tm)) seminars, writes solar business curriculum, and consults for new solar businesses. Liz's latest resources and opinions can be found at  SolarToday.org/Liz and at VerveSol on Twitter.