Saturday, January 20, 2007

What is Real Energy?

This blog got it's title from something William McDonough said. If you don't know about William McDonough, he co-wrote "Cradle to Cradle," a book about designing things so that you know how they end up once people are done with them. His web site has a sample of his writings.

What I heard him say in an interview with Michael Toms was that nature does everything on current accounts. There is no borrowing. On considering this, I think we can say that there is a little saving going on. Seeds, for example, can store energy for a long time until they sprout, and a camel's hump is made for storage. But the point about not borrowing is pretty profound I think. You can't use tomorrow's sunlight today and repay it in two days time. The energy input is taken up instantaneously and all the follow on activity is
a process of expending that energy, from leaf to ruminant to steak to microbes, it is all one run.

Now, there are many kinds of energy: chemical, potential, kinetic, nuclear and all of that. I got to wondering just what the difference is between the natural flow that McDonough was describing and what we do. It seems to me that when we capture the dregs of ancient supernovae, or dig up ancient forests, we are dealing with something unreal. Not that the supernovae didn't happen or the forests of a hundred million years ago did not grow, but that they are just not part of the present natural flow. We have to summon them rather than participate in them.

So, the ghostliness of those sources of energy got me to the present blog title, Real Energy, owing to its substantialness compared to the spectres. I know that some people call this renewable energy and so do I most of the time, but there are some who call nuclear energy, the supernova's spirit, renewable, thinking that breeder reactors somehow make things perpetual. I'm not interested in extent into the future, I'm interested in the present natural flow, the here and now. This, being the only reality we have, is where the term Real Energy comes from.

Probably the RealClimate title had an influence as well.


Anonymous said...

I'm not convinced that the language of "real" (for renewable) and "ghostly" (for fossil and nuclear) energy is helpful in any way. To be helpful, these terms should help us understand some aspect of their nature better than we otherwise do.

But to me, calling fossil and nuclear energy a dead or phantom energy source seems only to be a propaganda trick of name-calling. There is no fundamental distinction of these energy sources in terms of their historic "relic" nature. Even solar and wind power comes from a non-renewable fusion reaction in the sun. This is on a par with fissionable ores in terms of their cosmic origin -- you mentioned supernovae as being like fossil-like. So is the primordeal hydrogen in our sun. Geothermal energy is produced by fusion reactions in the Earth's core, so that's again "ghostly." If you really want to wax philosophical, all means of producing usable energy are depleting a non-renewable reserve of entropy, which seems likely to be a relic from the very earliest moments of the universe.

So from this perspective, the origin of the energy source is really not a pertinent or helpful idea. What is important is how much of it there is remaining in the Earth, and how expensive is it to remove the by-products from the environment. I think that some quick calculations show that nuclear energy can supply energy for a long time before we start running out of uranium. But we'll certainly need breeder reactors to milk our limited supply of uranium for all it's worth. It's most promising that solar and wind power is becoming more practical. But they still require a system like coal or nuclear power as backup.

Chris Dudley said...

The hydrogen fusion is actually a sign of a low entropy origin which is a little difficult to understand but absolutely critical to life. The difficulty in understanding the low entropy origin leads to such perambulations as the anthropic principle or cosmic inflation theory. The recurrence of these somewhat mystical ideas in science shows just how bizarre this situation seems.

The occurance of a very small amount of fissionable heavy elements in a Ni56 (high entropy) environment is much easier to understand and is expected by pure chance.

This does indeed point to a fundemental difference: with nuclear power we are using the castoff dregs while with solar power we are part of the main show of the unfolding of the universe.

There is certainly evidence of fission within the Earth, this appears to be where the helium comes from, but it is not at all clear that this is the origin of most of the heat in the Earth since the heat of formation is adequate to explain what is observed. I do not know of anyone who suggests that fusion is a contributor to the Earth's internal heat and, so far as I know, low energy nuclear reactions require high deuterium loading which would be very difficult to achieve within the core or elsewhere in nature. Obviously the pressure and temperature at the center of the Earth are way too low for hot fusion.

I'm pleased that you are beginning to think of ghost energy in a secondary role. This a good step forward. It struts and frets its hour upon the stage and then is burned no more....

For uranium fission, that hour is brief: were we to convert all of our electric use to nuclear power we'd run out of fuel before the plants reached their design lifetimes. Breeders are not legal in the US.