And San Francisco is initiating a pilot program to collect dog poo to break down to methane to be used for powering stoves, turbines, heaters, and other equipment. http://dsc.discovery.com/news/briefs/20060220/dogpoop_ani.html

Perhaps the future of energy is diversification. I get the impression that we are always looking for "the source" to replace fossil fuels, but why not have 20 different and often local ways to produce energy, while eliminating waste!

Not to mention that diversification of energy sources would create a safety net for the power grid. There would be no single source that can be knocked out that could cripple the entire energy grid. Great observation, Alison!

This is great as a source of power - but even greater for global warming. A methane molecule causes an estimated 21-34 times more global warming than a CO2 molecule, so by burning the methane (and producing power as a bonus!) you keep tons of ultra-heat-trapping methane out of the air. Check out http://www.terrapass.com, they try to prevent global warming by installing methane digesters and buying green tags.

One potential catch though: it seems that a CO2 molecule lasts a lot longer in the atmosphere (100 years?) than a methane molecule (8 years?). If that's true, it reduces the gain by 12X, but you started with a gain of 21-34X, so you're still left with a gain (or global warming reduction) of 2-3X.

There's another problem with this: For resource-poor areas, this burns a lot of organic material that could be used to replenish the soil. One of the drives in preventing desertification is getting the locals to stop using dung for fuel. It's more plentiful than wood, and easier to collect, but it robs the soil of nutrients that should be returned to it -- hence the more efficient wood-burning stoves being promoted by groups like journeytoforever.

But when you burn something, aren't the nutrients (i.e. non-hydrocarbon minerals) left as ash? I was under the impression that burning crops or waste released all the H2O and CO2 into the air, while leaving all the minerals as ash. As long as the ash is composted or mixed with dirt (instead of letting it blow away) it seems fine...

"Perhaps the future of energy is diversification. I get the impression that we are always looking for "the source" to replace fossil fuels, but why not have 20 different and often local ways to produce energy, while eliminating waste!"
I agree with you. But going further is a concept called microgeneration. Simply put people should generate their own energy from sources directly available to them. I subscribe to this view and believe it to be how things will move in future. I live in the countryside and have built a passive solar house with evacuated tube solar water heater, PV panels, wind generator, mansonry stove, and a few other smaller renewable nic-nacs, and am planning on building a small biogas digester in the near future to use up the poo produced by my sled dogs. Where I live, in the mountains of central Spain, I have plenty of wind, sun, wood, and poo, and I try to use it all. Local generation eliminates the waste generated in transmission wires or pipes and takes advantage of energy in a highly distributed way with minimal impact in each location.

'For resource-poor areas, this burns a lot of organic material that could be used to replenish the soil." Biogas digesters don't burn poo, they decompose the organic matter creating methane gas as a biproduct. The resultant decomposed matter is a highly concetrated and rich liquid fertilizer more powerful and effective than untreated and unprocessed dung, not to mention safer.

i luke brackney think treehuggers are the bomb