While the “hydrogen economy” receives much media attention, there are serious problems with hydrogen as transportation fuel. The first is hydrogen gas is extremely explosive. Hydrogen must be pressurised to 250 atmospheres for use as fuel, requiring corrosion-resistant tanks that don’t rust, spring leaks and explode. Hydrogen’s low energy density requires fuel tanks 14 times as large to yield the same driving range. To get a 1400 km range, a tractor trailer needs 168 gallons of diesel. Hydrogen vehicles would require 2360 gallons of hydrogen, stored at 250 atmospheres. Dedicating that much space to fuel storage would drastically reduce how much trucks could carry, while the costs of high-pressure, corrosion-resistant storage tanks, would be astronomical. The two main options for producing hydrogen, generating from water and extracting from other fuels, both have energy efficiencies below 100 per cent, (takes more energy to produce than you get). Hydrogen vehicles (currently $1 million each to produce) would need a widescale hydrogen fuel distribution system. With a single hydrogen fuel pump costing $1 million, installing six at each of the 176 000 fuel stations across the US is more than $1 trillion, costs completely avoided with biofuels that use our current infrastructure.
Algae instead of corn for bio-fuel
Algae multiplies so quickly and produces so much oxygen per square foot that ponds with a total surface area five times the size of Colorado would be enough to start to reverse our growing CO2 problem. Algae triples in volume every day. Corn, with one crop a year, nets about 81 gallons bio-diesel an acre (soy nets 40). Algae yields as high as 15 000 gallons an acre. Enough biodiesel to replace all petroleum transportation fuels could be grown in about 9.5 million acres, far less than the 450 million acres used for crop farming in the US, and the more than 500 million acres animal grazing land. Hydrogen is dangerous/explosive, extremely expensive and nets zero energy, that is, it uses more energy than it creates. Algae converts CO2 to O2, is 30 to 50 per cent oil and converts easily to bio-fuel. Conservation reduces present and future production of CO2. Algae reduces EXISTING CO2. The government needs to quit looking at corn and begin massive and wholesale funding and grants for algae. A new state agri-business of algae farms? Or grants for ocean farming? Algae, pond scum also a planet saver? Yes, if we take action!
Tami Freedman
Ooltewah
United States
TO THE EDITOR: ‘Hydrogen economy’ a Boondoggle
09:00 Mon 07 May 2007
Comments
Comments by John Dobbins - 01:23 08 May 2007 | ||
 | I disagree with this article.
He dwells at length on the storage pressure and density of hydrogen as though there were no way to solve the storage problem. metal hydrides greatly increase the density of stored hydrogen at low pressure. Much research is ongoing to find better ways store hydrogen at low pressure and high denstity.
The statement:
" Hydrogen vehicles (currently $1 million each to produce)..."
is totally misleading. Obviously a prototype of anything is very expensive. He doesn't allow for the economies of scale and the amortization of development costs that apply to any mass produced product. There is no reason a mass produced hydrogen burning internal conbustion engine would be any more expensive than any other IC engine.
He apparently is saying the energy output of the hydrogen is less than 100% of the input energy to produce the hydrogen. So what? All energy conversions are less than 100% efficient. If you only get 80% energy back (from hydrogen combustion) from solar energy input to produce the hydrogen, that's fine. Solar energy is unlimited and safe. There are approximately
3500 megawatts of solar energy peak power per square mile at noon. If we have multi square mile arrays of solar panels in the USA Southwest deserts, you could supply enormous power to produce hydrogen and power the electrical grid. The hydrogen produced could power grid generators at night. These are real possiblities. It only requires continued R & D and commitment to getting off the oil addiction (which is inevitable since it will eventually run out). Solar is completely safe, scalable to any size and will never run out. |  |
Comments by Fran Barlow - 10:09 10 May 2007 | ||
| I'd like to add my endorsement to the further exploitation of algae for biodiesel. This approach is far the most promising route to the development of biofuels.
Algae can actually yield as high as 25,000 US gallons per acre of diesel if covered ponds with technology to upwell the water is used. Greenfuels have a system that can be tacked on to the flues of industrial and power plants absorbing emissions of 81% of NOx and 40% of CO2. When burned biodiesel's hydrocarbon output is much less than that of any other conventional fuel and there is a fraction of the PM, no benzine and so forth.
Since the algae produces starch one can also ferment this using the Ramey method, which uses to types of clostridium to produce butanol -- a four carbon ethanol product that can be swapped neat for gasoline and that produces similar fuel economy with greater safety. When burned, butanol leaves behind no Carbon Monoxide.
But it doesn't stop there. In addition the butanol produces hydrogen as a byproduct which can be used in stationary fuel cells to produce zero-combustion (no emission) electricity with pure water as "waste". The waste heat from the cell (about 670 kelvins) can also be used to either run a second turbine (combined cycle) for more power or for a cogeneration process (eg if you need steam for an industrial process such as gasification of coal).
Glycerol is also a byproduct of algae and this can be used in the manufacture of polymers (rather than petroleum).
Finally the algae yields up proteins -- animal feed ready -- and sulfates for fertiliser.
Algae can also be used in brackish water settings -- where crops won't grow and be fed by potentially harmful run off or sewage.
Some species of algae (eg c. rheinhardtii) can actually be used to produce hydrogen during photosynthesis (rather than oxygen).
It's high time this course was taken. In one step the US could overnight stop spending its blood and treasure protecting access to an environmentally hazardous resource, funding its enemies and polluting its skies while channelling much needed income to those of its farmers willing to use low grade land and waste water to make something commercially valuable.
How hard a decision can that be?
Fran | |
Comments by Larry J - 14:27 13 May 2007 | ||
| This is a very accurate article. However, I do not understand why no one is concerned about this Hydrogen Hype.
The new Honda Hydrogen vehicles use the hydrogen's chemical reaction to generate electricity to charge the batteries. These cars are 100% electric.
Why would we need a consumable product to charge batteries? I guess if we plug these cars in at night to charge them we would not be stuffing the pockets of the filling station owners.
We are going to be screwed at the pump once again. Only this time it's Hydrogen gas instaed of gasoline. This way they can continue to make money off of electric cars the same way they do gasoline cars.
The fleecing of America continues. | |
Comments by Alvin Davis - 04:52 14 Nov 2007 | ||
| So, then tell me why there is a truck company that's 18 wheel type is running hydrogen in there truck's? and saving them over 700usd a day in fuel
because you use the vapor, a small generator to produce the elect. to the hydrogen maker, you can make it out of steel to steel plates and make alot if you add a small amount of salt. and it go's into your intake and you start redusing your oil crap to your engine, the oil and car company's knowen this for 50yr but don't want us to do it.
I say "KILL" the oil company's
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