July 18, 2008


Like many people who started reading blogs "back in the beginning," I miss Steven den Beste. He used to throw splendid doses of cold water on various areas where fuzzy-thinking is common. One of them is alternative energy sources. He's posted a summary that is worth reading, if you think wind power or some such is in the near future going to take away our need for power generated by coal, oil and nuclear. (den Beste has serious health problems, by the way, that's why he now limits himself to lightweight blogging.)

....I don't blog about that kind of thing anymore. I never enjoyed blogging about energy, anyway, because for too many people "alternate energy" is more about religion than about physics. They believe that if we are just creative enough, we can overcome fundamental physical limitations -- and it's not that easy.

In order for "alternate energy" to become feasible, it has to satisfy all of the following criteria:

1. It has to be huge (in terms of both energy and power)
2. It has to be reliable (not intermittent or unschedulable)
3. It has to be concentrated (not diffuse)
4. It has to be possible to utilize it efficiently
5. The capital investment and operating cost to utilize it has to be comparable to existing energy sources (per gigawatt, and per terajoule).

If it fails to satisfy any of those, then it can't scale enough to make any difference. Solar power fails #3, and currently it also fails #5. (It also partially fails #2, but there are ways to work around that.)

The only sources of energy available to us now that satisfy all five are petroleum, coal, hydro, and nuclear.

My rule of thumb is that I'm not interested in any "alternate energy" until someone shows me how to scale it to produce at least 1% of our current energy usage. America right now uses about 3.6 terawatts average, so 1% of that is about 36 gigawatts average.

Show me a plan to produce 36 gigawatts (average, not peak) using solar power, at a price no more than 30% greater than coal generation of comparable capacity, which can be implemented at that scale in 10-15 years. Then I'll pay attention.

Since solar power installations can only produce power for about 10 hours per day on average, that means that peak power production would need to be in the range of about 85 gigawatts to reach that 1%.

Without that, it's just religion, like all the people fascinated with wind and with biomass. And even if it did reach 1%, that still leaves the other 99% of our energy production to petroleum, coal, hydro, and nuclear.

The problems facing "alternate energy" are fundamental, deep, and are show-stoppers. They are not things that will be surmounted by one lone incremental improvement in one small area, announced breathlessly by a startup which is trying to drum up funding...

It's impossible to argue with most of the people who talk about "alternate energy;" They want to believe, and just don't hear anything like this. Plus, most people can't think. The average person, even with a university degree, can't think clearly about these things, and doesn't want to. For instance, the concept of scaling is basic to all technical discussions. But how many people will even understand, not to mention respond intelligently, if you tell them their favorite scheme "won't scale?" (It doesn't have to be a technical subject; there are things that work in small groups but not in large groups. Or small countries, but not large or diverse countries.)

Posted by John Weidner at July 18, 2008 9:25 AM
Weblog by John Weidner