Mea megawatt culpa

Three issues ago, I cited Senator Harry Reid’s comment about how 100 square miles of Nevada desert, filled to the gills with solar panels, could supply the annual electricity needs of the United States. A couple of readers were skeptical and did some research. As it turns out …

One 190 watt solar panel costs about $850 and measures 14.4 square feet. There are 2.78 billion square feet in a 100 square mile area (which is a square 10 miles by 10 miles, so one side would be the distance from Boomtown to the Wells Avenue exit, roughly). It would take almost 194 million panels to cover that 100 square miles. On a good, sunny day, those panels would produce 36,800 megawatts of electricity in an hour. It’s important to remember that a megawatt is a MILLION watts. So the panels would be pumping out a not insignificant 36.8 billion watts an hour.

Well, 36,800 megawatts an hour equals approximately 441,000 megawatts per 12 hour day. And that number times 300 (allowing for 65 cloudy days a year, or 17 percent, which seems reasonably conservative, considering the overall sunniness at our fantasy site somewhere in southern Nevada equals about 132,000,000 megawatt hours of electricity a year. Multiply 132 million watts by a million, and you get a production of 132 TRILLION WATTS of electricity a year.

Let’s trim 10 percent because, well, because nothing is ever going to work at 100 percent efficiency all the time. That leaves us with a solar farm that pumps out approximately 120 trillion watts of electricity a year. Not bad. That’s some serious power.

Unfortunately, it won’t come close to powering the country. According to the Department of Energy, the U.S. bumps along on a little over 4 billion megawatts a year, or 4 QUINTILLION WATTS of electricity. Which means, alas, that my skeptical readers are correct. One hundred square miles of Southern Nevada desert isn’t gonna cut it. In fact, according to one egghead’s calculations, it would take more like 2,500 square miles of solar panels to feed the United States, not 100. So our sun farm in the sticks of Clark County would be a mere 1/25th of what is needed to get the job done.

Where did Senator Reid go wrong? This is a guess on my part, but I think I saw the same factoid he or perhaps someone on his staff saw. A factoid that stated that enough solar energy FALLS on a 100-square mile area of the Nevada desert to power the country. Unfortunately, our ability to COLLECT that energy, at least at our current primitive level of collective technology, is sloppy and inefficient enough to where a whole lot of it gets away.

And yes, it would cost A LOT to fill 100 square miles of desert with solar panels. And the labor cost? Fuhgeddaboudit. It’d be enough to make Great Pharoah himself say, “No way, Ra.”