Tuesday, February 06, 2007

If you think OIL is a trap...

kw: book reviews, science fiction, energy, political drama

I got about halfway through The Green Trap by Ben Bova and realized he'd presented all the technical secrets; the second half of the book would continue the chase-capture-violence-escape-sex sequence that I'd already grown tired of. So I "ruined" it and jumped to the last twenty pages to see the denouement. The title actually gives it away; there is no happy ending here. The "hero" dies, the girl proves false, the minor villain does die while the major one wins everything. Kind alike real life.

The core idea: Cyanobacteria (which I once knew as "blue-green algae") have been cracking water for its hydrogen, and releasing the oxygen they don't want just then, for three billion years. A little genetic tinkering, and they can be forced to overdo it, so they release both gases, which people can then separate and burn together to recapture the solar energy the critters used in the first place.

Secondary idea: Should it work, it's worth billions, or trillions, but will wreck the current oil-based economy, foreign relations, and a number of other dominoes. So of course, people get killed right and left by the varying powerful factions.

Interesting side idea: Rather than have big central hydrogen-producing stations, put a bug-containing membrane in each vehicle to produce it on demand.

Bottom line: Cyanobacteria are less than five percent efficient in catching sunlight. Suppose they are tinkered with until they catch 25%. Then you need that membrane to be the size of a barn, about ten meters on a side, to grab sufficient sunlight to power a 20HP (i.e. quite small) car motor. Secondly, consider the waste problem. Photosynthesis runs best when a plant or green cell is growing and multiplying, so you create a lot of waste. LOTS of waste. Perhaps a ton per driving mile. We have silicon solar cells that do 25% now, and all the waste that is going to be produces has been produced once you buy it.

Bova's writing style keeps one going, but the content eventually wore me down so I skipped half the book. It didn't take much thought to see the flaws enumerated above, so I give him only a D+ for this idea.

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