Energy dependence seems to be the topic of the day, or at least the last two days. David Roberts posted a link yesterday to an eye-opening article about the surge of interest among the Amish of Ohio for solar PV panels. I had always assumed, wrongly, that the Amish eschewed electricity, period. Actually, they just don’t like depending on the outside world.

Meanwhile, renewed violence in Nigeria, a major petroleum producer, is giving oil markets the jitters.

So is home-produced energy always better?

That is certainly a perennial argument made by proponents of biofuels. Yet as the share of corn for ethanol grows (27 percent of this year’s U.S. crop), the nation’s fuel supply will be increasingly subject to the vagaries of the weather. Here’s a foretaste from the DTN Ethanol Center:

Corn has had a couple of wild-and-crazy weeks [on the Chicago Board of Trade], first rallying on planting delays and then collapsing on more planting progress than expected. Corn ran up over 30 cents and then fell over 40 cents. The decline also came into the bullish teeth of an extensive flooding problem in the Western Corn Belt. It is estimated by elevator sources that northwest Iowa will have to be 20 percent re-planted and southwest Iowa has been behind schedule right along. Flooding is also evident in Missouri, Nebraska and South Dakota. The Toledo, Ohio, area is also flooded and elevator sources there say 10 percent of the corn will need to be replanted. [Emphasis added.]

It is always salutary to be reminded of the fact that crops yields are affected by factors largely beyond human control: precipitation and temperature. Rutgers University researchers James Eaves and Stephan Eaves made this point in a paper they released earlier this year: because of weather-induced corn yield fluctuations, the supply of ethanol produced from corn is not necessarily less inherently risky than the supply of oil.

That is not, of course to say that there aren’t plenty of good reasons to reduce consumption of petroleum products. But the various alternatives are not all less prone to disruption.