Finally, someone tells the truth about all these feel-good fantasies.
Being an engineer who passed through my "Mother Earth News" days in the 70's, I have tried much of this stuff on a small scale. The only one of these schemes that actually has some benefit is solar hot water, and then only in the right climate.
This latest "hydrogen economy" is probably the biggest hoax yet. Until three years ago, I was involved in filling the space shuttle external tank with a few million gallons of liquid hydrogen, so I have some knowledge in that area, too.
I can only begin to list all the safety hazards of dealing with LH2.
- It must be stored at -423 degrees in order to keep it liquid (That takes energy, whether your "hydrogen-powered-vehicle" is running or not.)
- And where do you vent off the hydrogen gas, into your garage? Hydrogen becomes explosive at a 4% concentration in air. At KSC, we had flare stacks where the gaseous hydrogen was burned off. I guess you could tow one of those on a trailer behind your "green" car.
- It also burns with an invisible flame - you can walk right into a raging hydrogen fire and not even see it. That's why technicians used to carry brooms in front of them when they had to walk into the hydrogen farm area at the Cape. That's why the space shuttle has little pieces of butcher paper glued on the orbiter-ET disconnect - if they catch fire, the folks in the firing room know they have a hydrogen fire.
- Hydrogen expands 600 times when it changes from a liquid to a gas. A small leak can cause big problems.
- You must use cryogenic transfer lines and dewars to move the LH2 around. These are very expensive, vacuum jacked lines and tanks which must be serviced on a routine basis to keep the vacuum down or you will soon experience that 600-times-expansion in a very explosive way.
I can't wait to see the first auto accident involving a "clean-burning" hydrogen-powered vehicle. It will make those car bombs in Israel look like childs toys. Then the feds will mandate that all drivers wear flame-retardent coveralls, leather gloves, and non-sparking footwear, I'd guess.
I think the current popular support for fuel cell technology is idiotic. Nuclear and fossil fuels are our current best bets for power generation.
Sometimes, however, renewable technologies can be employed locally for good effect--low head hydrodynamic is the best example which pops to mind.
"I can only begin to list all the safety hazards of dealing with LH2." Don't forget that it is 11 times less dense (as a liquid) than plain old gasoline. It delivers 3 times as much energy per pound but that still leaves you 11/3 = 3.6 times LESS efficient (volumetrically) than gas. In other words, for the same range your fuel tank must be almost 4 times larger.
If you try to use compressed hydrogen gas, it becomes even more absurd.
--Boris
I can only begin to list all the safety hazards of dealing with LH2.Tell you what...let's run a few "issue ads" featuring the average soccer mom and her kids entering an SUV. Rapidly intersperse video of the HINDENBURG disaster. Then show pics of the "after" condition of the kids at WACO.
Then the voiceover about "CRISPY CRITTERS". End with "The HYDROGEN Economy...it's a BAD idea!!!