Hyundai Struggles Against Infrastructure Issues To Meet Global FCV Sales Target

How about this http://www.greencarcongress.com/2015/06/20150623-cui.html

It depends on if a technology can reach a tipping point. EVs are almost there, IMO. I recall a study about range anxiety & how far people drive in EVs. Researchers found that without charging stations, drivers were extra cautious and didn't drive very far. When chargers were added to the community, EV drivers drove much farther, but never used the chargers. The EVs really did have enough range, and knowing chargers were available reduced anxiety. Curing that anxiety is one obstacle to an EV tipping point. Another is initial price. Already, EVs are cost comparable on a total life cycle basis because so much money is saved on fuel. But vehicle buyers still have trouble getting over the initial price premium. As prices come down--and I do believe they will--that barrier will erode. Once those two hurdles, I think EVs will be able to stand on their own without subsidies.

"If there were a way to use solar energy to isolate the abundant hydrogen already present in the atmosphere (as well as water), we could have a virtually limitless energy source without any pollution at all." IMO, that already exists. It's called solar power and using the electricity it generates instead of dealing with hydrogen at all. It meets your goals of using solar energy, being virtually limitless, and lacking pollution. It has the added benefit of being much more efficient, simpler, and thus cheaper than dealing with hydrogen. But the idea brings up an interesting topic: what options do we have for harnessing solar energy? I can think of three off the top of my head: photoelectric/photovoltaic, photosynthesis (or some other chemical reaction), & thermal. (There may be others; I don't claim the list is exhaustive.) Photoelectric/photovoltaic: The common PV cell. I think efficiencies are somewhere around 11%. There are much more expensive types that utilize more light wavelengths as get over triple that efficiency, but since we're not talking NASA, I'll just stick with the low-teens. (GE was going to attempt a product with 14% to 17% efficiency, but with dropping prices, they concluded the effort wouldn't be cost-effective.) I'm not sure if prices will continue to drop. Much of it was driven by China subsidizing them to push competitors (like GE) out of the market, so in other words, the price drop wasn't real. The price of PV may already be competitive depending on what you assume the price of natural gas (and other fuels for power plants) does over the next 20 yrs. I expect incremental improvement on the technology without any spectacular revolutions. Chemical reactions (photosynthesis): Plants. While sunlight does cause several chemical reactions (break down of plastics, dyes, etc.), the only one I can think of that stores productive energy is photosynthesis. I have a theory that the next revolution in technology will be biological machines, and harnessing chloroplast-like devices to produce sugar, alcohol, or hydrocarbons fits that mold. From Wikipedia, the efficiency of photosynthesis is 3% to 6%, with a theoretical max of 11%. Plus, there are losses associated with using a fuel it produces. Ideally, harnessing solar energy through a photosynthesis-like process would be to make finished materials (like wood), not fuels. For the foreseeable future, I think it will be limited to agriculture, and no new energy-storing reactions will be available. Thermal (water heaters): Some power plants use sunlight to boil water. I saw a number of 15% annual efficiency for these power plants, and I don't know their cost compared to PV. I think there's a lot of untapped potential in this area, particularly in using solar for any process that requires heat, e.g., it can be used to purify water, power ovens in food production, or preheat chemicals in refineries. I would think it worthwhile to set up desalination plants in CA that use sunlight to boil water in a tank and then condense the steam. A side benefit of using solar energy is that it creates shade. For many areas, excess sunlight means needing to cool buildings, and AC is an energy hog. It's much better to prevent buildings from heating up in the first place, and a great way to do that is to put them in the shade by collecting solar power above them. In fact, I'm surprised by solar power plants I've seen that don't put offices, etc., under the solar collectors.