I went to engineering school right after the Arab Oil Embargo, and alternative energy was a hot topic then. All the same stuff you hear of nowadays. They even offered entire courses on it , which I took. Then my first mini career was in the power plant biz, before Volker killed it with interest rates and the Saudies killed any interest in alt. energy with their big oil field discovery.
For the last 5 years I’ve been researching what’s changed, and it is frighteningly little. Solar cells are still expensive and only have a 15% conversion efficiency. They developed the new cost reduced film technology, but that knocks down efficiency to 7%.
Wind power works where there is wind constantly. Generators are mature technology and are already 90 some percent efficient.
Geothermal, tidal, ect. work where they are available.
Looks like coal gasification and synfuel is out because it makes too much CO2.
Good news is 3rd gen nuclear is way better than 1st gen plants.
Hybrid cars are good, and battery technology is finally getting barely good enough for all electric cars to be practical.