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The 660 Gallon Brewery Fuel Cell
An anonymous reader writes "Australia's University of Queensland has secured a $115,000 grant for a 660-gallon fuel cell that should produce 2 kilowatts of power. A prototype has been operating at the university laboratory for three months. This fuel cell type is essentially a battery in which bacteria consume water-soluble brewing waste such as sugar, starch and alcohol, plus in this instance produces clean water."
Note that TFA indicates that this is a method to remove brewer's waste, with the byproduct of producing electricity. As a method for producing electricity in general, it is not a clean method because you'd first have to produce alcohol (which would then we cleaned by the bacteria). Producing alcohol produces *VAST* amounts of CO2.
I have worked as an assistant winemaker at a small vinyard. Our vats are 3000 litres apiece. Even with these small vats, the temperature reached by the yeast cell division is HOT to the touch (but not enough for thermal electricity generation). If you were to walk into the room where the vats are without first ventilating the room, you would pass out because the oxygen in your lungs feels like it is literally sucked out (not sure of the actual physical process involved). If no one were around, you would die from asphyxiation. It is wierd sensation, let me tell you.
Or 200 10 watt compact florescent bulbs, which is all we use. Not 200 of them, of course. But in a 5000 square foot home, we do have quite a few.
More importantly, that's an average rate, so storage during off hours could yield considerably more output. If you sleep 8 hours of a 24 hour day and aren't home for another 8 while you work, that leaves 8 hours at 6 kilowatts if you control your inactive power consumption decently, and even if you don't, you could still end up with a great deal more than 2KW available to you. Storage also allows for short peak usage (startup of furnace blowers, refrigerator motors, air conditioners and so on... takes a lot more to start most motors than it does to keep them turning, even under load.
I would definitely be willing to make room for a 700 gallon or so tank; I wonder what the feeding, cleaning, and environmental requirements for a production version will be. I've been seriously considering solar, but the high installation cost and the relatively short lifetime of silicon cells (20 years or less) doesn't work out very well. If this thing can run long term and isn't a maintenance nightmare, I'd jump on that puppy instantly.
I've fallen off your lawn, and I can't get up.
New Belgium Brewery, most famous for Fat Tire and Sunshine, produce 10% of their electricity using the methane that is produced from bacteria feeding off of their waste water.
The digester in this small (330k population) plant generates methane which fires converted gasoline engines to generate electricity. The waste heat goes to warming the digester. There's still solid waste though.
Burning methane is a GoodTHing. Methane has approx 27 times the greenhouse effect of CO2, so burning it produces power and reduces greenhouse gases.
Engineering is the art of compromise.
Well I realize that the process would be carbon neutral once you're growing plants to process, I was mainly thinking of the fact that since we're producing CO2 in high concentration, we may as well use it in high concentration to boost plant growth. The next step would be just making sure the CO2 isn't able to hit the atmosphere at large before the plants have a chance to use it. Other than that, you're right- it doesn't really matter if the CO2 gets out there as long as there are plenty of plants to compensate.