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Friday, June 27, 2008

A little reminder about Hydrogen:

This article was e-mailed to me in reference to my article "Facts on the Oil Problem" I have received some good feedback from several people Just wanted to says thanks for the encouraging remarks If you have something you would like too share please don't hesitate to forward it.

Anthony Landaeta Jr
Posted 6/27/2008

The Hydrogen Economy-Energy and Economic Black Hole -
By Alice Friedemann
A few quotes:
‘‘…Hydrogen isn’t an energy source – it’s an energy carrier, like a battery. You have to make it and put energy into it, both of which take energy. Ninety-six percent is made from fossil fuels, mainly for oil refining and partially hydrogenated oil--the kind that gives you heart attacks (1). In the United States, ninety percent is made from natural gas, with an efficiency of 72% (2), which means you've just lost 28% of the energy contained in the natural gas to make it (and that doesn’t count the energy it took to extract and deliver the natural gas to the hydrogen plant). …’’
‘‘…Only four percent of hydrogen is made from water via electrolysis. It’s done when the hydrogen must be extremely pure. Since most electricity comes from fossil fuels in plants that are 30% efficient, and electrolysis is 70% efficient, you end up using four units of energy to create one unit of hydrogen energy: 70% * 30% = 20% efficiency (3). …’’
‘‘…producing hydrogen at an overall 25% efficiency, or 3 units of wind energy to get 1 unit of hydrogen energy. The best solar cells available on a large scale have an efficiency of ten percent, or 9 units of energy to get 1 hydrogen unit of energy. If you use algae making hydrogen as a byproduct, the efficiency is about .1%…No matter how you look at it, producing hydrogen from water is an energy sink. If you don't understand this concept, please mail me ten dollars and I'll send you back a dollar…’’
‘‘…No matter how it’s been made, hydrogen has no energy in it. It is the lowest energy dense fuel on earth (5). At room temperature and pressure, hydrogen takes up three thousand more times space than gasoline containing an equivalent amount of energy (3). To put energy into hydrogen, it must be compressed or liquefied. To compress hydrogen to 10,000 psi is a multi-stage process that will lose an additional 15% of the energy contained in the hydrogen.…’’
‘‘…If you liquefy it, you will be able to get more hydrogen energy into a smaller container, but you will lose 30-40% of the energy in the process. Handling it requires extreme precautions because it's so cold – minus 423 F. Fueling is typically done mechanically with a robot arm …’’
‘‘…Let’s assume that a hydrogen car can go 55 miles per kg (5). A tank that can hold 3 kg of compressed gas, will go 165 miles and weigh 400 kg / 882 lbs (12). Compare that with a Honda Accord fuel tank that weighs 11 kg / 25 lbs, costs $100, and holds 17 gallons of gas. The overall weight is 73 kg / 161 lbs (8 lbs per gallon). The driving range is 493 miles at 29 mpg… According to the National Highway Safety Traffic Administration (NHTSA), ‘’Vehicle weight reduction is probably the most powerful technique for improving fuel economy. Each 10 percent reduction in weight improves the fuel economy of a new vehicle design by approximately eight percent’…’’
‘‘…Fuel cells are also heavy: "A metal hydride storage system that can hold 5 kg of hydrogen, including the alloy, container, and heat exchangers, would weigh approximately 300 kg (661 lbs), which would lower the fuel efficiency of the vehicle," according to Rosa Young, a physicist and vice president of advanced materials development at Energy Conversion Devices in Troy, Michigan (12). …’’
‘‘…Fuel cells are expensive. In 2003, they cost $1 million or more. At this stage, they have low reliability, need a much less expensive catalyst than platinum, can clog and lose power if there are impurities in the hydrogen, don’t last more than 1000 hours, have yet to achieve a driving range of more than 100 miles, and can’t compete with electric hybrids like the Toyota Prius, which is already more energy efficient and low in CO2 generation than projected fuel cells. (3)…’’
‘‘…Hydrogen is the Houdini of elements. As soon as you’ve gotten it into a container, it wants to get out, and since it’s the lightest of all gases, it takes a lot of effort to keep it from escaping. Storage devices need a complex set of seals, gaskets, and valves. Liquid hydrogen tanks for vehicles boil off at 3-4% per day (3, 13). …Hydrogen also tends to make metal brittle (14). Embrittled metal can create leaks. In a pipeline, it can cause cracking or fissuring, which can result in potentially catastrophic failure (3). Making metal strong enough to withstand hydrogen adds weight and cost.…’’
‘‘…Leaks also become more likely as the pressure grows higher. It can leak from un-welded connections, fuel lines, and non-metal seals such as gaskets, O-rings, pipe thread compounds, and packings. A heavy-duty fuel cell engine may have thousands of seals (15). Hydrogen has the lowest ignition point of any fuel, 20 times less than gasoline. So if there’s a leak, it can be ignited by a cell phone, a storm miles away (16), or the static from sliding on a car seat. …’’
‘‘…Canister trucks ($250,000 each) can carry enough fuel for 60 cars (3, 13). These trucks weight 40,000 kg but deliver only 400 kg of hydrogen. For a delivery distance of 150 miles, the delivery energy used is nearly 20% of the usable energy in the hydrogen delivered. At 300 miles 40%. The same size truck carrying gasoline delivers 10,000 gallons of fuel, enough to fill about 800 cars (3). …’’
‘‘…Another alternative is pipelines. The average cost of a natural gas pipeline is one million per mile, and we have 200,000 miles of natural gas pipeline, which we can’t re-use because they are composed of metal that would become brittle and leak, as well as the incorrect diameter to maximize hydrogen throughput. If we were to build a similar infrastructure to deliver hydrogen it would cost $200 trillion. The major operating cost of hydrogen pipelines is compressor power and maintenance (3). Compressors in the pipeline keep the gas moving, using hydrogen energy to push the gas forward. After 620 miles, 8% of the hydrogen has been used to move it through the pipeline (17). …’’
‘‘…The laws of physics mean the hydrogen economy will always be an energy sink. Hydrogen’s properties require energy to overcome waters’ hydrogen-oxygen bond, to move heavy cars, to prevent leaks and brittle metals, to transport to the destination….Any diversion of declining fossil fuels to a hydrogen economy subtracts that energy from other possible uses, such as planting, harvesting, delivering, and cooking food, heating homes, and other essential activities. According to Joseph Romm “The energy and environmental problems facing the nation and the world, especially global warming, are far too serious to risk making major policy mistakes that misallocate scarce resources (3). …’’

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