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Making Fire From Water
LexNaturalis writes "Gizmodo has a story out about a new product that makes fire from water. Gizmodo explains how it works: 'Ordinary tap water (preferably distilled) is supplied to the fireplace through a pipe or tank, a 220 volt electrical service then separates the hydrogen and oxygen atoms through electrolysis, the Aqueon ignites the hydrogen, and ta-dah, fire! The oxygen is then added for color and brightness, while the rest is released into the room. It doesn't require venting because it doesn't produce any harmful emittents like carbon monoxide -- just water vapor.' The manufacturer's website has more information on the science behind this new product. While splitting water to get hydrogen and oxygen is not new, this product will likely make the technology more accessible to the masses and might hopefully show that hydrogen is a more attractive fuel than petroleum-based fuels."
No, what this shows is that hydrogen is simply a derivative of fossil fuels, and is in fact an extremely expensive, inefficient and almost useless way to store and transport energy.
Let's see, we start with huge lumps of coal, convert them to steam, convert the steam to electricity, and then use the electricity to make hydrogen which (in a fuel cell) we can convert back to electricity. Energy is lost at every step along the way. In particular, compressing the hydrogen from atmospheric pressure to storage tank pressure loses about HALF the total energy, so even if the fuel cell is 100% efficient, you've still lost HALF the energy you started with.
But commercial hydrogen is not produced by electrolysis. It's produced from natural gas and steam. So let's see, we start with natural gas, a product which has the following properties:
- Cheap
- Easy to store and transport with widely available equipment
- Can run through cheap, widely available engines
- Fairly clean burning (compared to diesel)
- High energy density in compressed tanks
and we convert that to hydrogen which has the following properties:- Very very expensive
- Very difficult to store. The only real-world proven way to store it at a high density is to liquify it. That will never be a practical option outside of aerospace industry
- Can be burned in regular engines, with regular engine efficiency, or can be burned in extremely expensive fuel cells. There is no realistic possibility of fuel cells becoming cost competitive in the foreseeable future.
- Low energy-density for real-world storage (compressed tanks, etc). Fuel cell cars have a range of less than 200 miles usually.
- Oh, and it's clean burning! Finally after all the bad things about H2 we come to one good thing!
- It makes the whole global warming and oil dependency problems worse becomes it takes so much energy is wasted in the process of converting fossil fuels into hydrogen.
The one thing that could help is that you can make hydrogen from clean nuclear energy and from clean solar energy, but given that hydrogen electrolysis is not cost-competitive with even cheap fossil fuel electricity, why should it be cost competitive with much more expensive solar electricity?I regret that our government is involved in subsidizing this whole boondoggle, but I have no worries that it will continue in the long-term. Some small improvements in lithium batteries, and some reasonable production economy in lithium batteries will make electric cars competitive with plain old ICE cars, and the hydrogen fuel research pork programs will shrivel up and die.
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With some mumbo jumbo about future fuels to sell it to people. In reality it's an electric heater. Almost all uses of electricity are electric heaters, and unless they affect things outside the room, they're mostly 100% efficient electric heaters. It's easy to be 100% efficient at turning useful energy into heat, after all. (furnaces are not 100% efficient because they must vent waste gas outside, along with some heat.)
This just happens to turn electricity into heat in an amusing way, at a high price. There are, of course lots of other interesting ways to turn electricity into heat. My computers are doing plenty of that right now.
If they really were pitching this as a way to heat the house, it would be as bad an idea as any other electric heater. They are way poorer in total "well to home" efficiency than gas furnaces, but often used because they are cheap to install (expensive to run), very easy to meter (for landlords), and on the positive side, can be easily individually controlled on a room by room basis, which sometimes can make them more efficient than heaters that either heat the whole building or nothing at all.
But I doubt this is meant as such a heater. It's meant as an art piece, to wow your fellow millionaire friends.
Has it been over a year since you last donated to the Electronic Frontier Foundation
But that's not true. According to a May 2004 article in SciAm (sorry, only available for purchase, check it out at your local library instead) says the total green house gases produced by coal plants used to generate the electricity needed to generate the hydrogen produces more green house gases than used by current gasoline engines.
They even include the supply chain side of transporting and storing hydrogen vs gasoline. They found that a fuel cell driven by gasoline actually produces less emissions than a fuel cell driven by coal.
The problem is the loss of effiency. To convert water to hydrogen via electrolysis from coal, the loss from coal to tank is 78%. After the hydrogen is used in a fuel cell, it loses an additional 43%, for a total loss of 92%.
Compared to gasoline.. pumping a gallon of oil, transporting to a refinery, turning it to gas, and transporting the gas to a filling station takes away 21% of the energy potential of the oil. For a conventional IC engine, 85% of the energy in the gas tank is lost. That brings it to a total of only 88%.