Originally Posted by st falcon
50 years is unlikely dont you think? I mean, Honda already has the Clarity.
No. Having a few hydrogen-powered cars is one thing, having a million is something else. Many things can be done as boutique, niche products that absolutely cannot be done on an economy-wide scale. Hydrogen requires massive (and expensive) infrastructure changes--far more than simply electrifying a car fleet. It would take decades to simply implement that. I expect future cars will be tailored to their purpose, e.g., we will have more commuting specific cars (likely EVs) and long-range cars. Garbage & mail trucks will be a type of hybrid so they can regenerate losses from frequent stops while still being able to be refueled quickly.
Another fundamental problem of hydrogen is: Where do you get it? Unlike oil, coal, sunlight, etc, it does not occur in a useable form in nature--it is not an energy source, but an energy storage medium. It must be produced (from natural gas, electrolysis of water, etc.). If you make it from fossil fuels, why not just use the fossil fuel? If you make it using electrolysis, you must already have the electricity, so why not just use that?
(For comparison, electrolysis is around 70% efficient. Hydrogen engines are around 30% efficient, and fuel cells are around 40% efficient--in other words, ~20-30% overall efficiency. Compare that to batteries at 85% and electric motors at 90% for a total of 75% or more. You could go 3x as far in an EV as a hydrogen car given the same starting energy supply.)
A lot of equipment for use with hydrogen is very expensive. Fuel cells can add $50k-100k to a car. (The estimated cost of producing the Clarity is $300k) Storage tanks are much more expensive than those for gasoline, as are any form of hydrogen transport.
The benefit of hydrogen over batteries is the energy density & refueling rate. Like gasoline, you can quickly add enough hydrogen to a car to enable it to go a few hundred miles. You can't do that with batteries. If the energy expenditure needed to produce hydrogen drops and we can develop cheap ways to handle/store/transport hydrogen, then it can be practical, but I anticipate we will have just as many breakthroughs with battery tech making it cheaper, lighter, and faster thus eroding many of hydrogen's benefits.
I do expect more hydrogen cars to make it to the roads in the coming decades, but they will be very limited. I don't expect them to be common at any time before I retire. I do, however, expect EVs to rise in popularity in the same way as hybrids have over the last ten yrs. They won't make up the majority, but they will be a common sight. Also like hybrids, the price premium of EVs should decrease over the next ten years.
Your solar costs are way off. Ford is partnering to offer 2.5 kW residential systems for $10k (after fed rebates) to go with the eFocus. (This is much cheaper than systems I priced a few years ago.) Solar systems produce about 1200 kWh/kW/yr, so that system will produce around 3000 kWh/yr = 111 full fill-ups for the eFocus/yr = 8500 mi/yr. Solar panels can last ~30 or more, so lifetime costs (assuming no increase in efficiency of the EV driven) are $10k/(30*8500 mi) = $0.04/mi. (A 30 mpg Focus & $3/gal gas = $0.10/mi for comparison.) EVs do have a steep up-front cost that makes the break-even point many years down the road. Given the current rate of improvement in solar, it is not unreasonable to expect cost/kW to drop by 50% in ten years.
The issue of the electric grid's capacity is also off. It is maxed out at peak loads now, but not at average load. We have gobs of over-capacity at night, and if EVs are charged then, we won't need much new grid infrastructure; our base electric generation would be more stable/consistent, meaning it can be generated more efficiently. However, it is unreasonable to expect everyone to only charge at night. But I've already started seeing utilities to push peak-pricing, which forces shifting consumption to night. Additionally, as solar (and other on-site power generation) gets cheaper/better, more systems will be installed, which reduces the need for increasing the capacity of the grid.