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Microbes Pass Valuable Gas

Posted by michael on from the tiny-bubbles dept.

inimicus writes "Wired reports: 'With a reliable source of hydrogen, fuel cells can produce energy with water as the only byproduct.' The good news is that there's a functional prototype (measuring 0.7 square centimeters and less than 1 millimeter thick) that produces 1 microwatt of power -- approximately enough to power a digital wristwatch. Personally, I'm intrigued by the concept of powering my laptop with sugar-water..."

4 of 44 comments (clear)

  1. How is the "Battery Life"? by Marillion · · Score: 2, Interesting

    Obviously this is still a long way from running my laptop. But, does anyone who might be involved in this stuff know what the projections are for how long a typical "charge" will last before you have to "recharge." The metaphor being how long you can go before you must resupply nutrients and/or enzymes and/or biologicals.

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    This is a boring sig
  2. Hydrogen balooney by Muhammar · · Score: 4, Interesting

    "a 53-cubic-foot reaction chamber would provide enough hydrogen to run a 200-kilowatt fuel cell and supply energy for about 20 houses"

    1. I do not believe that they can produce that much hydrogen from this much volume - maybe she is talking about the peak output her 15 liter tank, multiplied by the factor to get to 200kW "to power 20 houses".

    2. 10kW per house is actualy very little - this is another example of "data massage". Average hair dryer takes about 2kW, so does ironing your shirt or vacuum your room. I am not talkig about things like electric laundry dryer or A/C. I *lived* in place which had 20Amp circuit brakers (which gives 20kW at 120V), and the circuit brakers were out all the time. We had an electric heater, but neither A/C nor laundry in the apartment.

    3.Running fermentor is not the easiest thing to do - you have to keep the microbes happy - the output can vary, there can be problems with contamination (some mold gets in which wipes out the bacterias over time) etc. And they smell bad.

    4. Using a fermentation tank to power laptop is pure unmitigated balooney - here the power source can be more expensive than with household source. With laptop, the premium is on weight+size. Much more compact and fairly affordable source of hydrogen for laptops can be sodium borohydride: this is a common industrial chemical, water-stable and 40g of the stuff + 40g of water produces 8g of hydrogen, which is one of the best weight ratios with nonelectrolytic sources of H2.

    5. Enviro-technologies development: most of the time it's a confederacy of shabby science, political pressure and populism. The surest way to protect enviroment is to find a different job for pop-science enviromentalist - preferably in gender studies or postmodernist deconstruction university departments.

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    I doubt that we will ever figure out - and I suspect that even if we did figure out we couldn't do much about it
    1. Re:Hydrogen balooney by mfarver · · Score: 2, Interesting

      10kW per house is actually very little - this is another example of "data massage". Average hair dryer takes about 2kWMost hairdryers are about 1500 watts, and only used for short (5 minute) periods of time. A standard outlet is only capable of supplying 15 amps, even when connected to a 20amp circuit.I live in a 1000sqft house in the South Central US, with high Air Conditioning bills. A "bad" month is 1300kwhrs, divide that by 720hrs in a month and you get only 1.8kw per hour on average, 10kw is actually closer to peak usage.

      I *lived* in place which had 20Amp circuit brakers (which gives 20kW at 120V), and the circuit brakers were out all the time. So did I.. the entire house was on one 20amp breaker, if the fridge turned on when the TV or Microwave was on, it would trip. A breaker mostly trips on peak loads, but neither the microwave or fridge runs 24 hours. (The TV was another story). Actually a 20amp breaker is will trip if asked to give more than about 18amps for longer than 5 minutes. Plus you have to derate heavily for poor power factor loads. Most motors, electronics (TV, computers and those annoying little wall transformers have lousy PF, between .5 to .7, meaning you can only get 50 to 70 percent of the circuit's rated power into the device, with the rest being lost mostly as heat in the wires between you and the generator.

  3. Actually.. by IpsissimusMarr · · Score: 2, Interesting

    There was a piece done one MSNBC just last week about Ford (or maybe Chrystler) developing a hydrogen fuel cell car. And they already have a working prototype.

    They have a new car making scheme with it. The fuel cell is very small and is located in the bottom chassis of the car. You can have one or two types of 'bottoms' of fuel cell and just put a different 'top' chassis on them.

    With two fuel cell designs you can make SUVs, compacts, etc. just by changing chassis.

    Production expected in 5-8 years I believe. :)

    --
    "Engineers do the work of man, Physicists do the work of God"