Pretty much. One of the biggest problems with a lot of renewable energy is it's not reliable. Sun doesn't shine, wind isn't blowing, etc. So you need a way t

Pretty much. One of the biggest problems with a lot of renewable energy is it's not reliable. Sun doesn't shine, wind isn't blowing, etc. So you need a way to store energy in a buffer to smooth out fluctuations. Hydrogen is looking like the best long term bet for that. You might even be able to use it for hydrogen cars, but then you run into problems with transportation and crash-proof storage that you don't have with just a tank in your back yard.