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To: Tailgunner Joe
While it is true that a hydrogen-based economy is deemed inevitable for reasons of efficiency,

A "hydrogen-based economy" is not only NOT "inevitable", it is an impossibility.

It will ALWAYS take a greater amount of energy from some OTHER SOURCE just to manufacture the hydrogen.

5 posted on 02/10/2003 2:15:59 PM PST by Willie Green (Go Pat Go!!!)
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To: Willie Green
A "hydrogen-based economy" is not only NOT "inevitable", it is an impossibility. It will ALWAYS take a greater amount of energy from some OTHER SOURCE just to manufacture the hydrogen.

What's your point?

Hydrogen is merely an energy storage medium, like compressed air to run your air drill.

Unless they figure out that oil is still being created by the earth (probably is, but not at the rates we're using it). A hydrogen economy is a certianty in some future century.

With the cost of gasoline what it is today, it is practically at the cost break even point now. So that day may be sooner rather than later.

9 posted on 02/10/2003 2:22:50 PM PST by narby
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To: Willie Green
It will ALWAYS take a greater amount of energy from some OTHER SOURCE just to manufacture the hydrogen.

Yes, some other source... but if that source is sunlight, using a version of photosynthesis?

Harnessing the Horsepower of Pond Scum

Researchers Hope to Magnify Yields of Hydrogen Gas from Renewable Green Algae

By Kathleen Scalise, Public Affairs Posted February 16, 2000

A metabolic switch that triggers algae to turn sunlight into large quantities of hydrogen gas, a valuable fuel, is the subject of a new discovery reported by Berkeley scientists and their Colorado colleagues.

"I guess it's the equivalent of striking oil," said plant and microbial biology Professor Tasios Melis. "It was enormously exciting. It was unbelievable."

Melis and postdoctoral associate Liping Zhang of Berkeley made the discovery -- funded by the U.S. Department of Energy Hydrogen Program -- with Michael Seibert, Maria Ghirardi and postdoctoral associate Marc Forestier of the National Renewable Energy Laboratory in Golden, Colorado.

Currently, hydrogen fuel is extracted from natural gas, a non-renewable energy source. The new discovery makes it possible to harness nature's own tool, photosynthesis, to produce the promising alternative fuel from sunlight and water. A joint patent on this new technique for capturing solar energy has been taken out by the two institutions.

So far, only small-scale cultures of the microscopic green algae Chlamydomonas reinhardtii have been examined in the laboratory for their hydrogen production capabilities, Melis said.

"In the future, both small-scale industrial and commercial operations and larger utility photobioreactor complexes can be envisioned using this process," Melis said.

While current production rates are not high enough to make the process immediately viable commercially, the researchers believe that yields could rise by at least 10 fold with further research, someday making the technique an attractive fuel-producing option.

Preliminary rough estimates, for instance, suggest it is conceivable that a single, small commercial pond could produce enough hydrogen gas to meet the weekly fuel needs of a dozen or so automobiles, Melis said.

The scientific team is just beginning to test ways to maximize hydrogen production, including varying the particular type of microalga used and its growth conditions.

Many energy experts believe hydrogen gas one day could become the world's best renewable source of energy and an environmentally friendly replacement for fossil fuels.

"Hydrogen is so clean burning that what comes out of the exhaust pipe is pure water," Melis said. "You can drink it."

Engineering advances for hydrogen storage, transportation and utilization are beginning to make the fuel feasible to power automobiles and buses and to generate electricity in this country, Seibert said.

"What has been lacking is a renewable source of hydrogen," he said.

For nearly 60 years, scientists have known that certain types of algae can produce the gas in this way, but only in trace amounts. Despite tinkering with the process, no one has been able to make the yield rise significantly without elaborate and costly procedures until the Berkeley and Colorado teams made this discovery.

The breakthrough, Melis said, was discovering what he calls a "molecular switch." This is a process by which the cell's usual photosynthetic apparatus can be turned off at will and the cell can be directed to use stored energy with hydrogen as the byproduct.

"The switch is actually very simple to activate," Melis said. "It depends on the absence of an essential element, sulfur, from the microalga growth medium."

The absence of sulfur stops photosynthesis and thus halts the cell's internal production of oxygen. Without oxygen from any source, the anaerobic cells are not able to burn stored fuel in the usual way, through metabolic respiration. In order to survive, they are forced to activate the alternative metabolic pathway, which generates the hydrogen and may be universal in many types of algae.

"They're utilizing stored compounds and bleeding hydrogen just to survive," Melis said. "It's probably an ancient strategy that the organism developed to live in sulfur-poor anaerobic conditions."

He said the algal culture cannot live forever when it is switched over to hydrogen production, but that it can manage for a considerable period of time without negative effects.

The researchers first grow the algae "photosynthetically like every other plant on Earth," Melis said. This allows the green-colored microorganisms to collect sunlight and accumulate a generous supply of carbohydrates and other fuels.

When enough energy has been banked in this manner, the researchers tap it and turn it into hydrogen. To do this, they transfer the liquid algal culture, which resembles a lime-green soft drink, to stoppered one-liter glass bottles with no sulfur present. Then the culture is allowed to consume all oxygen.

After about 24 hours, photosynthesis and normal metabolic respiration stop, and hydrogen begins to bubble to the top of the bottles and bleed off into tall, hydrogen-collection glass tubes.

11 posted on 02/10/2003 2:26:44 PM PST by DJtex
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To: Willie Green
A "hydrogen-based economy" is not only NOT "inevitable", it is an impossibility. It will ALWAYS take a greater amount of energy from some OTHER SOURCE just to manufacture the hydrogen.

Well, you are correct in your 2nd statement. I don't know about "impossible", however. Just expensive. Coal gasification is a very interesting approach and doesn't seem to be the boondoggle that fusion power represents (always fusion tomorrow, never fusion today.) The coal gasification plants are actually in production in some countries - but they are expensive compared to petroleum and natural gas.

From the link: "Rather than burning coal directly, coal gasification reacts coal with steam and carefully controlled amounts of air or oxygen under high temperatures and pressures. The heat and pressure break apart the chemical bonds in coal's complex molecular structure, setting into motion chemical reactions with the steam and oxygen to form a gaseous mixture, typically hydrogen and carbon monoxide. (Gasification, in fact, may be one of the best ways to produce clean-burning hydrogen fuel in the future.)"

and

"Coal gasification offers a much more efficient way to generate electricity than conventional coal-burning power plants. In a conventional plant, heat from the coal furnace is used to boil water, creating steam for a steam-turbine generator. By contrast, a gasification-based power plant uses the hot, high pressure coal gases exiting a gasifier to power a gas turbine (in the same manner as natural gas). Hot exhaust from the gas turbine is then fed into a conventional steam turbine, producing a second source of power. This dual, or "combined cycle," arrangement of turbines - a configuration not possible with conventional coal combustion - offers major improvements in power plant efficiencies. Today's conventional combustion plants are typically 33-35% efficient (fuel-to-electricity). Coal gasification offers the prospects of boosting efficiencies to 45-50% in the short-term and potentially to nearly 60% with technological advancements. Higher efficiencies translate into better economics and inherent reductions in greenhouse gases."

The thing that looks interesting is that this just takes coal (of which we have an abundance), generates electricity from it (with a bit more cost and less pollution) and it generates hydrogen as a side effect.

13 posted on 02/10/2003 2:30:00 PM PST by dark_lord
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To: Willie Green
It will ALWAYS take a greater amount of energy from some OTHER SOURCE just to manufacture the hydrogen.

//////////////////////////
you're going to have to put on a happy face when you say that. such confident predictions have very often proved wrong in the past.

as it is the 1.2 billion bush proposed for for hydrogen research pales compared to the 12 billion proposed for AIDS help. which issue is more vital to american interests. protection of US homosexuals and african blacks or securing US energy independence.
14 posted on 02/10/2003 2:30:51 PM PST by ckilmer
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To: Willie Green
A "hydrogen-based economy" is not only NOT "inevitable", it is an impossibility

You could be right. On the other hand, that's the same thing they said about flying in planes or a myriad of other things that have now turned out to be feasible. Your statement reminds me of patent director who wanted (or did) close the patent office on the premise that everything that could be invented already had been.
20 posted on 02/10/2003 2:36:02 PM PST by pt17
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To: Willie Green
"It will ALWAYS take a greater amount of energy from some OTHER SOURCE just to manufacture the hydrogen."

Facts are so inconvenient to the socialists that wish to make us dependent on an easily controllable source of energy.

43 posted on 02/10/2003 3:13:11 PM PST by editor-surveyor (Best policy RE: Environmentalists, - ZERO TOLERANCE !!)
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To: Willie Green
It will ALWAYS take a greater amount of energy from some OTHER SOURCE just to manufacture the hydrogen.

Yes, but that isn't the point. We're not looking for greater efficiency or lower costs. We want vehicles that emit only water vapor from the tailpipe.

65 posted on 02/10/2003 4:48:31 PM PST by RightWhale
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To: Willie Green
Willie,

You missed the big picture. Please follow the logic. The Hydrogen car is to the Arabs what Star Wars was to the USSR. The threat that the yanks might actually pull this off makes them far more passive in dealing with an "angry customer".

66 posted on 02/10/2003 4:51:30 PM PST by Natural Law
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