In the wake of our Saturday article on sustainable energy companies and mixed energy futures, some people wondered how realistic all this stuff really was. On Monday, I pointed out that they wouldn't replace nuclear power's growing footprint, just as fossil fuels will continue to be our top energy options for a while. Still, there are changes happening at the margins:
"London's Science Museum is reportedly considering methods to cut their utility bill by burning human waste or using it to feed microbial fuel cells. Management predicts that visitors' crap could generate 1,530 kilowatt hours of electricity per year."
Winds of change, indeed. No word on whether all cafeterias will be converted to Tex-Mex food as part of the program, but Boing Boing blog has more details (Hat Tip: worldchanging.com).
UPDATE: Maybe not so powerful. Bart Hall and Futurepundit explain.
Whatever happened with that refinery you posted about last year, that turned poultry offal into gasoline, heating oil, and water? That looked like a killer app to me.
"visitors' crap could generate 1,530 kilowatt hours of electricity per year."
Sorry to disappoint the dreamers out there, but the crap in this idea is primarily conceptual. At a dime per kWh the savings would be about $150 per year. A fifteen year useful life is all that can be expected of such systems. Discounting repairs and maintenance the maximum savings realised will be about $2250 over the life of the equipment.
At 6% interest, they can afford to spend $1500 to build the thing, which is at least an order of magnitude low, and probably closer to two orders of magnitude.
In reality, the savings in electricity costs would never even begin to pay for upkeep, maintenance, and repair. Given a few more white elephants like that ... they might even have enough raw material to make it cash flow.
What Bart Hall said.
It's a stretch, but I can think of a few ways that such an effort might be worthwhile. One is that the system would pre-process the sewage, taking some of the load off the central treatment plant. (The effect of one system in a museum would be negligible, but if applied across the board it could be substantial.) The other is that such a system might make a good science exhibit; it is not often that you get to see actual working hardware in a museum setting.
I suspect that fermentation of sewage solids to produce gas would offset more energy use than microbial fuel cells. Processing the trash and food waste left by patrons in an anything-into-oil plant would be equally educational and probably have a much higher payback.
Reminds me of Mad Max Beyond Thunderdome. "Not shit, e-ner-gy!" ;^)
Still, burning bio waste produces COx anyway, so I don't see how this would benefit us that much in the long run.
Keep an eye on Iceland, they're heavy into hydrogen. All we need is a way to produce it at a reasonable cost, and we're set for an unlimited supply of zero emission energy, without all the negative connotations that nuclear energy still has.