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Comment Re:Hydrogen is not gold (Score 1) 71

We've gotten a bit off track here.
I originally responded to a post which proposed making H2 from electricity, storing it and then converting that back to electricity. I pointed out that this is very inefficient (you only recoup about 30%). This is a very poor method to store electricity. I also pointed out that there is no need for long term battery electricity storage since short term fluctuations in wind, solar, hydro tend to even out. Recently published models of electric production from renewables have show that it is possible to support the grid entirely with renewables.
http://www.worldbank.org/en/ne...
http://www.nrel.gov/electricit...

CH4 production and use for heating is a different subject.

Comment Re:Hydrogen is not gold (Score 1) 71

There is no need for long term energy storage.
Wind, solar and hydro have daily variations but reliable generation when averaged over even very short time spans. There is no need to store this energy for more than a few days.
If you have a source of H2 (such as this article posits), you can tap that as needed (similar to CH4) if you can work out a way to get if from the middle of the ocean. However, the thermodynamic inefficiencies of converting electricity to H2 and back to electricity (30%) makes it uneconomical (as well as unnecessary). H2 is a very poor energy storage medium (thermodynamically).

Comment Re:Hydrogen is not gold (Score 1) 71

Good sir (I assume you are a male, pardon if not).
I was merely responding to the prior post which was extolling the virtues of storing electrical energy as H2. I pointed out a few problems with the scheme and why it is a bad electricity storage medium.
I'm not sure what set you off on the tangent of Elon Musk but it seems that you have a pathological hatred of the man.
Batteries do have their limits but are much better than H2 storage of electricity which is grossly inefficient.
It's really hard to store any energy for long periods of time. Trees are probably the best storage of energy for winter heat.
Fortunately, renewable sources of electricity (wind, solar and hydro) only need small amounts of short term storage since they are renewed daily with predictable fluctuations.

Comment Re:Hydrogen is not gold (Score 1) 71

The problem is the round trip efficiency of making H2 with electricity and then converting it back to electricity in a fuel cell is only 30-50% efficient compared to storing the electricity in a battery which is 90+% efficient.
In addition, compressing, storing and transporting H2 is difficult and causes further losses and inefficiencies. (H2 has a nasty habit of leaking through most containers)

Comment Student loans are a government subsidized scam (Score 3, Informative) 49

Not surprising to see Amazon to look for this easy money. Banks have been ripping off students and the government for years with this scam.
Interest rates are high... much higher than most loans.
Loans are guaranteed by the government so no risk to the lender.
Students can't declare bankruptcy and discharge the loans so they are on the hook for life.
Side note: when my daughters started college a few years ago, I was deluged with calls from student loan salespeople. Reminded me of home refinance deluge just before the crash. Fortunately, I had saved enough for their education so I was able to tell them to get lost.

Comment Re:Detroit (Score 3, Insightful) 13

Ford, GM and all the other "established" automakers have been very slow to introduce EVs and the cars they have made are severely crippled (low range, expensive, bad design, etc.). They have mostly been producing limited production "compliance cars" which they are forced to make to avoid regulatory penalties.
Tesla demonstrated that there is significant demand for a practical electric car without compromises. I do hope that the old guard gets its act together but I think this may be another case of established producers reluctant to cannibalize their existing ICE cars where they have invested billions in ICE technology and production. I think they hope this whole EV car fad will go away and they can get back to making muscle cars, SUVs and pick up trucks powered by dinosaur juice.

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