A couple of articles about solar power caught my eye this week. To be very clear from the outset, I am a huge proponent of solar power via all the myriad technologies out there today as well as those under development. I have a solar PV system on my house that generates more electricity than my family consumes on a monthly and yearly basis (by a decent margin). Keep these facts in mind as you read my comments on the pieces I found.
The first article dealt with solar installations just in the state of Colorado, which “jumped in 2011″. CO installed 91 megawatts (MW) in 2011. Nationwide, according to the author, solar installations more than doubled to 1,885 MW or ~1.9GW – a not insubstantial number in and of itself. California installed 542 MW, New Jersey 313 MW, Arizona 273 MW, and New Mexico 116 MW. Additionally, the weighted average cost of installed systems dropped 20% – also a piece of good news.
While reading up on something unrelated, I came across a graphic from a post at CleanTechnica which was touting U.S. solar installations. As you can see below, they point out that 17 nuclear power plants worth of solar peak power shipped in 2010.
I’m not sure what size power plants they use for comparison, but for now I’ll assume that it was the same size that I used for a class analysis last semester – 0.75GW. Note further the key adjective: “peak power”. That is the power that the solar systems can deliver on a clear day when the sun is as perpendicular to the arrays as is possible. That value lasts for only a short period out of any day with current technologies. This isn’t a criticism – my system had a peak power rating too but I know I can’t expect that power to be generated throughout the day and certainly none will be generated at night.
Okay, with those caveats out of the way, here is my take on all this information: those national numbers aren’t nearly enough to address our CO2 emissions. From the same analysis I referenced above, I calculated that the U.S. needs a minimum of 25 0.75GW nuclear power plants installed per year to meet our stated 2020 GHG reduction goal of 20% of 2005 emissions. That’s well more than the solar PV-equivalent that was installed in 2010. If we instead want to hit our stated 80% GHG reduction goal by 2050, we need a minimum of 111 0.75GW nuclear power plants (or their equivalent) installed per year through 2050. Those numbers include a very conservative increase of 0.32% energy demand per year through the same time frames.
The solar industry has made great strides in the U.S. – but I am convinced it is nowhere close to enough to address the magnitude of global warming that is likely to occur. These numbers are good news, but we need a whole lot more great news. Which means we need some serious policy work done to ensure that great news is reported someday soon.