No Such Thing As A Free Lunch
By way of Jonathan Adler, I came across this Gray Lady editorial concerning California’s renewable-energy mandate. Renewable energy means, for the most part, solar and wind power. The primary concern raised by the author is that while greenhouse gasses and fossil fuels are not implicated in solar or wind power, they do exact an environmental cost. The central lesson, though, is an old one: every benefit carries a cost.
The cost which was the focus of the article was the cost of land. Referring to the recently-constructed Ivanpah solar power plant near the California-Nevada border and the route from Los Angeles to Las Vegas, this plant produces at peak output 370 megawatts, taking up 3,600 acres of desert floor — about five and a half square miles of space. That’s an output of just under ten acres per megawatt.
I’m not sure where the author got his numbers that California’s power consumption is 57,000 megawatts at peak use, making the one-third mandate 17,000 megawatts, but assuming that’s correct, Ivanpah is about 2% of the mandate at the cost of losing five and a half square miles of surprisingly environmentally sensitive space. From this, it appears that a total area of about 130 square miles would need to be set aside to meet 50% of the renewable energy mandate. That’s roughly the equivalent of three times the size of the City and County of San Francisco (city and county are politically unified and geographically co-extensive). The entire city.
Wind farms also chew up real estate — again, taking the numbers in the editorial at face value, wind plants generate 5.07 megawatts per square mile, making the other 50% of the mandate cost 1,675 square miles, or more than the entire area of Butte County (north of Sacramento) or nearly the size of Ventura County (north of Los Angeles). The author asks, do we really want to devote that much land to coming up with one-third of our electricity needs?
Another cost he raises is that of steel; both wind and solar plants are made of quite a lot of it. Of course, so are coal and nuclear plants, which also incorporate quite a bit of concrete. I wonder if the large amounts of steel involved is something of a red herring here, although the materials used is a factor that should be considered. As isthe process of making and mantaining the materials in question; wind turbines require at least some petroleum products to use as lubricants since they use moving parts, they need substantial excavation to find the elements necessary to make the rare earth magnets in their generators, and who knows what kind of toxins are used to manufacture photovoltaic cells? Again, these technologies may be on balance better for the environment than coal, natural gas, or nuclear plants, but that does not mean they come without cost.
An old friend of mine now works for General Electric servicing and maintaining wind turbines. He likes his job and has spent considerable time out in the field; he is enthusiastic about the technology and upcoming innovations and efficiencies that will make it even better. He says the most common objection to wind power he hears is bird strikes — and he insists that birds are smart enough and have good enough eyesight to see windmills and fly above them. I suppose he would know; if windmills were serious dangers for birds, there would be rings of bird carcasses around each windmill or wind farm consistent with a distribution pattern of the windmill throwing the birds around. I’ve never seen anything remotely like that and my friend, who is out there in wind farms all over the country every day, has said he’s seen more dead birds in his own back yard, killed by his neighbor’s cat, than he has out in the fields.
Compare that low wildlife cost to the relatively high wildlife cost of a large desert solar plant — displaced but reasonably loveable and cute animals include tortoises, coyotes, jackrabbits, and hawks. This does not consider mice, rats, snakes, scorpions, or other kinds of un-fuzzy, un-cute animals which are nevertheless part of the desert ecosystem, and it does not consider some very slow-growing plants that get destroyed like manzanita, Joshua trees, agaves, and cacti. And, when the desert floor is cleared for development, the floor of the desert absorbs less of the already-rare rainfall because there are fewer plants there to take the water in before it hits the hard pan and resurfaces to evaporate.
Two more significant costs not considered at all in the article are water and money, both of which are precious and scarce commodities here in the Golden State. The state does not have a lot of money to spare and coal technology is by far the cheapest kind of plant to create that generates reliable electricity. Water is also quite rare these days despite our recent wet winter, and solar power plants use a surprising amount of it — not just in the cooling-and-condensing cycle that is supposed to make the generator turbines spin.
It seems, though, that we are spending a lot of time and energy focusing on greehouse gas emissions, specifically carbon gasses, and that’s probably all the result of the Al Gore movie. We aren’t investing a lot into electriciy efficiency, we aren’t giving a lot of thought to the space that these relatively inefficient technologies will take, and practical fusion technology is still about twenty years in our future (just like it was twenty years ago; a fusion researcher I knew in Tennessee has cynically quipped that he feels like fusion technology will always be about twenty years away) but there isn’t much being considered by way of new technologies.
One thing is clear from the NYT article: in terms of acerage, solar is immensely more efficient than wind. The problem, of course, is that the idea of setting aside three entire cities’ worth of space to come up with power is ridiculous and insanely destructive.
But one solution to the cost of space already exists — retrofitting existing structures. The entire renewable energy mandate could be filled with 166,400 acres of retrofitted roof space. A single-family home could host about 2% of an acre on its roof and commercial structures would vary with their size. Are there 8.3 million homes in the desert communities of California? Well, no. Are there that many buildings if you count commercial structures? I’m not sure, but we’d probably be reasonably near that target. The problem here is that retrofitting existing structures takes a lot of time, labor, and money. And money’s another thing we don’t have a lot of.
Once again, no free lunches here. But the article is useful to remind us that when we consider our environmental future, we ought to keep in mind that we are always going to be trading problems for other problems, and what seems like a coherent solution now to our most pressing problems can easily create new problems down the road. It’s a balancing act and we have to do what is right and at the same time what is possible and at the same time what meets our needs.
If the answer were simple, we’d have solved this problem already.