I think we need to invest more in harnessing energy directly from the Sun. I don't care if it is algae, solar cells or any other way. Sun is our main indirect source of energy. Now we need to learn how to use it directly and not wait for eons to take advantage of it.
The Sun is an energy source today, we just have not learned how to use it effectively. This includes the generation of hydrogen from Solar energy for fuel cells . Norway is in the process of doing this right now.
There are many ways of using energy from the Sun. I have used Solar panels on my roof to provide me with hot water since 1980 and it still provides me with 100% of my hot water over 6 months of the year. That is just a start. We need more direct use of the Sun.
Yeah, solar energy is a great idea but it does little for transportation.
Hydrogen from solar? Hydrogen is a great short range commuter fuel
and as cryogenic liquid a wonderful rocket fuel, but the effort required to make it usefully compact DESTROYS anything that resembles efficiency.
we need alternatives that take liquid form at room temperature.
STOREABLE fuels.
Hydrogen even as compressed gas isn't storeable because it literally leaks through every known material.
the only thing that makes Hydrogen Fuel cells attractive is
the fact that by WEIGHT they can store more electricity
than lead acid, metal hydride or Lithium Ion batteries.
Compared to ANY liquid fuel the total energy density is very low.
Think of that group 65 battery under the hood of most rangers or Explorers and consider just how little stored energy that 30kilo block of lead... or other types of batteries.... represents.
Lead Acid Batteries only store 30-40Watt hours/kilo
NiCd 40-60Wh/Kg
NiMh 30-80Wh/G
Li Ion batteries store 160-200Wh/Kg
(that's 2.2lbs of weight to store 1/6-1/5 of a kilowatt hour)
Li Ion Polymer about the same, but somewhat more durable
I used the energy/Kg figuires, not the Power/Kg figuires because the power can be "flexible" depending on how rapidly the energy is drawn off.
Hydrogen Fuel Cells are limited only by their Hydrogen supply but
that is actually self-limiting because of volume considerations.
If fuel cells are the answer I really want someone to tell me what the question was....
AD