Other than Ethanol based fuels (which don’t even qualify as a stop-gap), what have the candidates said about solar, geothermal, wind, hydroelectric, tidal, biodeisel, hydrogen fuel cells, or the fully electric car?

(may be broke/outdated!)
Other than Ethanol based fuels (which don’t even qualify as a stop-gap), what have the candidates said about solar, geothermal, wind, hydroelectric, tidal, biodeisel, hydrogen fuel cells, or the fully electric car?