Scrap Irrigated Biofuel Crops & Plant Solar Farms!

After thinking some more about the numbers in yesterday's blog, here is a revolutionary idea: take irrigated biofuel crops already existing in the sunny Southwest (including California) out of production and put solar farms on those fields instead. Why? With no additional land used, we'ld have more energy in the grid, less chemicals in groundwater, less groundwater overdraft, and/or water leftover for the rest of us (including the rest of agriculture).

How is that going to work?

Water and Land Use Intensity of Solar Power vs. Biofuels

In continuing to grasp some basic land use and (ground)water use issues associated with energy production, it occurred to me during some recent discussions with my wondeful friends and colleagues Stephen Kaffka, Dan Putnam (both UC Davis), Margot Gerritsen (Stanford), and Wayne Spencer (Conservation Biology, San Diego) to compare the water intensity of solar power (see blog below) with that of another renewable energy source: biofuels. In the Southwest, all three (food&fiber production, biofuel production, and solar power) compete for land and water. Comparing water use and land use of a solar farm and an ethanol-corn farm in the Southwest on a per MWh-basis is not going to be favorable for biofuels, I figure - given all that irrigation water. But how bad is it?

Inconvenient Truth: Some "Green" Energy Can Guzzle Water

...that was the title that the Davis Enterprise used for Todd Woody's recent NY Times article exploring a recent surge in solar projects and a recognition of the need for sometimes significant amounts of water being consumed by large-scale commercial solar power plants. The title caught my eye. Being a numbers guy by nature, I was wondering what this article may be calling a "guzzler". The lead example for the article (and associated blog) were two planned solar farms in the Amargosa Valley (right next to Death Valley). Annual consumption would be 1.3 billion gallons of water per year. Sounds like a lot of water, doesn't it? I prefer to use cubic meters or acre-feet and compare it to equivalent farm-water use, which is where most of our water use is besides environmental flows - I think that would provide a much better perspective than the one-gallon water bottle we buy in the supermarket: