May 8, 2005

People unclear on the concept -- Hydrogen as Fuel

A number of people are looking at Hydrogen as a potential fuel. It burns clean and that is about the only nice thing that you can say. It is horribly inefficient, makes many metals it comes into contact with very brittle, it is explosive over a very wide range of dilutions (remember the Hindenburg) The most efficient way to store it is as a liquid (needing a Thermos (Dewar actually) to keep it at around -260C) and due to a molecular quirk, there are more Hydrogen atoms in one Gallon (or equivalent volume) of Gasoline than there are in one Gallon of Liquid Hydrogen. See these PDF files for a lot more information: Energy Fundamentals Electrolysis Lots of other links Anyway, a 15 year old High-School student was written up in the Cortez/Durango, Colorado newspaper for the following stellar achievement:
Cortez sophomore builds model hydrogen car
people-unclear-hydrogen-colorado.jpgWhile Micah Hinton aspires to be a heavy metal drummer, his real talent may be for engineering.

The sophomore at Southwest Open School in Cortez demonstrated this recently when he built a model car powered by hydrogen and placed it on display in a gallery at the school.

Hinton first suggested the idea while studying renewable energy in a class combining science and math taught by Colin Biard.

The notion baffled the teacher. "I never knew they existed," Biard said.

Hinton's car - about the size of a football - runs on distilled water. A solar panel provides energy to begin the reaction that splits hydrogen from water. The car is so efficient it can even motor and create hydrogen at the same time.

"When it's running, it's making water," Biard said. "When it's stopping, it's turning it back into hydrogen."

As a result, the fuel source is never depleted, and the car never needs a fill-up.

"It lasts forever," said Hinton, 15. "It will run off pure hydrogen."

Of course, he said, a life-sized version could look a bit different.

"On a commercial level, you're actually combusting hydrogen," Hinton said, so a solar panel would not be necessary.

During the six-week project, Hinton learned basic electrolysis and a little physics.

"It's interesting to me that you can use water as fuel," he said.

His teacher offered an additional review.

"This is an amazing gizmo," Biard said. "Micah had a lot of fun doing it."
Emphasis mine -- sorry to burst the bubble here but this is a toy kit available to anyone whose parents can spring the $120 price. Little Micah didn't "design" this -- he received a box with instructions and was able to assemble the component parts and make this kit work:
people-unclear-hydrogen-colorado-motor-kit.jpg
Unfortunately for him, the basic laws of physics are still outside his grasp (it is an Open School after all). The Solar Panel will need to power an 80 Horsepower engine to get any kind of performance from the vehicle (looking at carrying two adults and baggage and being safe to maneuver in traffic)(most current cars including hybrids are more than 100 Horsepower). One Horsepower is equal to 746 Watts A typical high power solar module generates 100 Watts and measures about 2 feet by 4 feet. Doing the math simple arithmetic it looks like little Micah's car will have to tote around a solar panel that is a square seventy-feet per side just to have decent performance during strong daylight hours with zero thought put in to making energy for use during nighttime. Of course, you are not going to be driving all the time during your day, just an hour or so to and from work. And you park at work? And need a parking space that is twenty feet per side to get enough surface area to get enough charge to limp home and of course, this will not generate any surplus Hydrogen for you to use on cloudy days and during winter. And I have not even begun to figure in the fact that motors and transmissions are not 100% efficient. Hydrogen is a wonderful buzzword for people who are trying to escape reality. H2 is not a fuel... Posted by DaveH at May 8, 2005 11:42 PM