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Consumer Hydrogen Fuel Cells
axis-techno-geek writes: "Ballard Power Systems of Vancouver, BC (in Canada, eh), has stated that it will start production this friday of their consumer level Nexa(tm) hydrogen fuel cell (article here). The power module generates up to 1200 watts of unregulated DC electrical power that can keep going as long as it is supplied with hydrogen, and produces no toxic by-products (i.e. you can use it in your home). They also have plans for a 250kW unit. No price as of yet."
For those insterested, here's a link to a more technical article on Hydrogen Fuel Cells:
a nd _fuel_cells/hydrogen_and_fuel_cells.html
http://www.altenergy.org/2/renewables/hydrogen_
Hydrogen seems like a neat way to store and transfer energy. It's a pure, simple, easy to transport, easy to extract form of energy.
However, there are number of issues that makes the short-term outlook for hydrogen difficult to justify running out and buying your own fuel cell...
In order to manufacture hydrogen in any meaningful quantity, "toxic" (environmentalist definition) by-products are an inevitable. To wit:
1. Electrolytic conversion from water requires electricity. The vast amount of electricity generated comes from icky dirty coal.
2. Extraction of hydrogen from fossil fuels still generates some toxic pollutants, and is still in relatively early stages of development.
No matter how meaningful quantities hydrogen are generated, greenheads will hate the fact that mother earth will incur vast amounts of greenhouse gases.
Shall we address the infrastructure problems associated with hydrogen? The costs of retooling fuel distribution channels to handle hydrogen?
Another issue conveniently ignored is the storage of hydrogen. Hydrogen, in its current form, is not particularly dense, requiring large tanks to store the equivalent energy stored in fossil fuels.
In the future, wind and/or solar power could provide the greenhouse gas-free hydrogen generation alternative to make it a sound fuel source from an environmentalist standpoint.
Advances in storage mediums, extraction and distribution should one day make hydrogen an exceptional fuel.
My car gets 40 rods to the hogshead, and that's the way I likes it!
Yes, Hydrogen can burn, when it reaches appropriate fuel/air mixture.. just like many other chemicals.
Propane or Natural gas are more dangerous than hydrogen.
Everyone thinks hydrogen is severely dangerous because of the Hindenberg disaster... which modern science attributes NOT to the hydrogen in the blimp.. but to the canvas covering of the ship that was, unbeknownst to them at the time, coated in a reflective paint made of SOLID ROCKET FUEL (they did not know that aluminum-oxide and some other chemicals were explosive)
The hindenberg got screwed up because a spark ignited the coating... which quickly spread across the whole ship.
Another fact.. people report seeing huge orange flames billowing from it.. but hydrogen burns as an almost invisible blue flame.... of course, the hydrogen added to the fire... but wasn't the cause.
Unfortunately the hydrogen problem's not solved yet... Would people feel OK if they've got a highly flammable and explosive gas cannister in their home?
You mean as oppposed to having natural gas piped into their home that would fill the house with gas if the pilot light just happened to go out while you on vacation? Tens of millions of families are living with this every day.
It's really not bad, certainly less dangerous and less explosive than the propane tanks and natural gas we have learned to accept. Much less so than tanks full of gasoline.
The most famous evidence of the unacceptable dangers of hydrogen was the Hindenburg explosion. A close look at the film shows some interesting results. The hydrogen went up (literally). The huge fire was caused by the diesel from the engines burning.
Then too, you have to consider "normal accidents" as well as the flashier exceptional ones. Burning hydrocarbons produce things link carbon monoxide. Not good. Very poisonous. Very insidious. Burning hydrogen produces water vapor. Much less nasty.
Of course, if you get your hydrogen by electrolyzing water and use electricity from burning fossil fuels you are still producing unpleasant stuff. But smokestacks are easier to track down and fit with scrubbers and other anti-pollution devices.
The man who never alters his opinion is like the stagnant water and breeds Reptiles of the Mind -- William Blake
I don't read ACs: If a post isn't worth so much as a nom de plume to its author then I wont bother either.
This means the sound should be about 400 times less at 20 meters or about 46 dBA at 20 meters. Another way to look at it is that this should be about as loud as a car 20 meters from you when you are one meter from this unit which should be rather quiet. That is unless you drive an old VW bug. :)
You mean as oppposed to having natural gas piped into their home that would fill the house with gas if the pilot light just happened to go out while you on vacation?
Most pilot lights on gas appliances have a thermocouple that will shut off the gas supply if the flame goes out.
Of course the last gas stove i used didn't seem to have this feature (though it was quite old)...
Many people are commenting about the difficulty of storing and transporting hydrogen gas. Here's a company with an interesting idea:
powerball.net
Their idea is to use a low-pressure tank filled with water and "powerballs" -- small plastic covered spheres of sodium hydride.
When the system wants to create more hydrogen gas, it uses a mechanical cutter to cut one of the powerballs in half. The sodium hydride instantly reacts with the water in the tank, producing sodium hydroxide and hydrogen (and a fair amount of heat):
NaH + H2O --> NaOH + H2 gas
When all of the sodium hydride spheres are used up, the result is a tank full of sodium hydroxide. The tank is then returned to their factory, where the sodium hydroxide is converted back into sodium hydride, so there's no waste stream from the process.
The cool thing about this system is that the hydrogen is stored and transported in solid form -- as metal hydride spheres, so you don't have the danger of high-pressure hydrogen to work with. The hydrogen is generated as needed at low pressure.
The site hasn't been updated in a while, so I have no idea if they've successfully brought a product to market, but I thought that this was a really interesting idea, and it would probably work fairly well with these sorts of fuel cells.
Unfortunately, the latest word is next summer at the earliest. Plug Power reported a $30 mil loss as of their past fiscal year and their press releases talk more about financial transactions rather than actual sales or product delivery so things aren't looking all that great for GE or Plug Power's offering right now.
What's worse for Plug Power is their initial offering doesn't take advantage of the fact that the fuel cell produces hot water as a waste product. Were they to design the unit to feed the hot water to a water heater, the fuel cell efficiency would be greater than 70%. Supposedly, the water capture feature won't appear until the second generation offering which makes you wonder who would buy the first one - especially at $15k a pop.
By coincidence, Chevron Oil in San Ramon, CA fired up their 200 KW unit today for the first time. That puppy set them back $850,000 or around $4,250 per KW. More info is available at
SF Chronicle.
Notice the odd ratios - The Chevron unit that's real and online cost about twice what GE's not-available unit is supposed to come in at. Maybe there's a hint there as to why Plug Power can't deliver.
The hour long episode on Discovery seemed rather concise and definite. They tested a sample of the hindenberg covering.. they checked the formula used... etc.
It's not an urban myth.
As for diesel.. the diesel fuel is at the *bottom* of the ship.. nowehre near where the huge, orange flames were shooting from.
I'm not saying Hydrogen can't explode.. it certainly does. But the Hindenberg didn't explode. It burned.
Modern solar panels have 20 year warrantees.
The solar energy density at the Earth's surface is approximately 1000W/m^2, not 22W/m^2. The latter figure is for a particularly inefficient solar panel, say one from 20+ years ago.
Flying over a mirror/boiler facility shouldn't be much of an issue, because the mirrors are pointed at the boiler, not straight up.
Thousands of tons of organic matter suitable for generating methanol or methane are produced and collected in our cities every day in the form of sewage and food waste. All we have to do is collect it.
A well-crafted lie appears unquestionable - Dama Mahaleo
Even better, you can use solar cells to split water and/or natural gas in to some H2.
Plants can't breathe oxygen either. They breathe carbon dioxide and produce oxygen. And some arboreal plants do indeed rely on the water in the air to survive.
I have no numbers to hand, but a fuel cell is much more efficient than any internal combustion engine currently available, and mole for mole uses half as much oxygen as hydrogen. I'd say it won't make much of an impact, expecially compared to IC engines, which also use plenty of oxygen but spew toxic fumes.
You don't have to produce your hydrogen as you're describing, and carbon dioxide is not necessarily going to be the byproduct even if you use hydrocarbons. You can also get your hydrogen via electrolysis of water, which produces oxygen as a byproduct. This process uses electricity, but it seems to me a well-designed system would use tidal flows to produce the power. You need to add an electrolyte to water for electrolysis to work, so sea water would be ideal, which means you might as well locate your hydrogen plants along the coast. A further byproduct would be the minerals originally dissolved in the water, which could then be put to good use. Such plants could be small and discreet, and need not place any strain to speak of on the local environment.
Come to think of it, such a system could be a boon for poor countries with a coastline and good tides but few other resources. They would become energy and mineral exporters.
I'd love it if someone could give this idea a good critique.
And the brethren went away edified.
GE will be marketing a fuel cell designed by PowerPlug next year. It uses natural gas or propane, and doubles as a space heater and water heater. These units are not any more dangerous to own or operate than a natural gas forced air heater.
Some Specs Are:
System Performance
Natural Gas 40% @ 2 kW output
Natural Gas 29% @ 7 kW output
LP Gas 38% @ 2 kW output
LP Gas 27% @ 7 kW output
Cogen Efficiency >75%
Fuel Cell Operating Temperature 160F
Exhaust Temperature (simple cycle) 220F
Power Quality IEEE 519 Compliant
Emissions
NOx 1 ppm
SOx 1 ppm
More info can be found at
www.plugpower.com
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This would be a good time to jump in and say "What about hemp?"
Last summer a group of young scientists drove an unmodified, diesel engine Mercedes Benz across country to promote hemp for fuel. They ran the car entirely on fuel created from hemp seeds. Although mileage was slightly impaired, the amount of pollution generated was greatly reduced because, unlike gasoline refining, which adds many noxious and dangerous chemicals, hemp fuels rely on natural methods.
This fuel "created from hemp seeds" was almost certainly just an alcohol. You can make alcohol by fermenting just about anything organic.
The problem is that both the growing of the plants and the fermenting are not terribly energy-efficient. Direct synthesis by burning CO2 in a hydrogen atmosphere would almost certainly be a better option.
The other thing that they might have produced from hemp is something vaguely resembling diesel fuel. This too can be produced fairly readily from many types of plant (think "low-grade vegetable oil").
The problem is that burning long-chain hydrocarbons cleanly is very difficult to do. This would probably not be a viable fuel source even if you weren't stuck with plants' energy efficiency.
The "...which adds many noxious and dangerous chemicals" line is mainly trolling on the part of whatever source gave you this information. The most dangerous things coming out of a gasoline engine are sulphur and nitrogen oxides. The sulphur came straight from the ground with the fuel, and the nitrogen oxides are a natural byproduct of burning any hydrocarbon under engine conditions. Hemp deisel would contain as much sulphur as the hemp did (all plant and animal matter contains some of it; at least one of the amino acids uses it). Hemp alcohol wouldn't... but I don't see any reason to use hemp alcohol over direct-synthesis alcohol.
In summary, I don't see any real advantage to using hemp as a fuel.
Effectively, you are electrolysing water while adding value to the natural gas. You can also capture the waste CO2 more easily.
Go here for more
Alex