N.O. Pundit

Solar Power

Glenn Reynolds has a piece up here: TCS Daily - The Silver Bullet Fallacy. Glenn:

Only two percent of the continental United States [land mass needing to be covered by photovoltaics for US energy independence - khg]! Er, in other words, an area slightly larger than Georgia. That seems like rather a lot, and I'm pretty sure that the environmental impact statement for such a project would be, um, daunting.

If you covered all the rooftops, roads, parking lots, etc., with solar collectors, you'd get an area the size of Ohio, which might do the trick, but solar power cells would have to be awfully cheap, and awfully durable, for anything like this to work, and I don't see it happening any time soon.

But this actually illustrates a problem with these sorts of scenarios. Bulovic's example is a bit over the top, and from this it's easy to make fun of the potential for cheap solar energy. But, of course, solar energy doesn't have to actually "supply all the U.S. energy needs" to make a big difference. Even relatively minor contributions -- say 5-10 percent -- would make a substantial difference in pollution, and in pricing of other energy sources, which is influenced by demand at the margin.

Glenn is of course correct. Viewing solar energy (or wind, hydro, geothermal, etc.) as 100% solutions to our energy needs demonstrates a flawed mindset on the energy marketplace if you will. We need highly portable energy (cars), peak use energy (summer AC use), failsafe energy (hospitals), specialized use energy (submarines), etc., etc. It is not a particularly useful exercise to calculate total US energy use, mix in photovoltaic efficiencies, divide by something or other and come up with 2% of land coverage.

That said, Glenn is also correct about what a big win it would be to replace even a small percentage of nonrenewable energy with renewable energy. Glenn bought a hybrid car recently. I don't know if his particular model has a plugin feature, but imagine it does (in other words, Glenn would have the option of storing some energy off the grid rather than relying solely on the gasoline engine to charge his car).

Now the game gets more interesting. Imagine that Glenn charges his car from a photovoltaic array. Here is one possible choice. Follow the link and you will find a 250 watt solar array with a proposed price point of $250. Now, without getting into all the load calculations, imagine a small array of these Sunflowers charging Glenn's car daily. Imagine that he received 20 "free" miles every day. Seemingly insignificant, but imagine his daily car use averaged around 20 miles a day. His 40+ MPG car now has an MPG asymptotically approaching infinity. Of course, theoretical and practical qickly diverge, so imagine his car getting 200-500 MPG. Not impossible. And cool as hell.

Let's do a fantasy calculation. Three Sunflowers cost $750. 20 "free" miles equals half a gallon of gas that Glenn did not spend money on. That's a savings of $1.50 a day. Call it $7.50 a week. Call it $375 a year in savings. In two years Glenn would have paid for his photovoltaics. More importantly (in my opinion) are the daily hydrocarbon savings and, well, the smug self righteousness personal pleasure of beating the commuting game in a significant way, all from a seemingly insignificant investment.

Caveat emptor: these numbers are pulled out of my a**. If I'm off by an order of magnitude, shove it up your cakehole.

Posted by nopundit at July 6, 2006 10:48 AM