I see no ideological contradiction in funding a Manhattan Project working on raising the efficiency of renewable alternatives. Such a project might actually have a net cost of $0.00 to the taxpayer, since funds and resources are already available in various agencies (DoD, EPA, DoE, etc) that could be routed to such a project.
Government research is, of course, public domain.
It’s all pretty simple, actually. For one example, what keeps people from buying solar panels and batteries and turning off the electric company? Cost, of course. Cost is related to efficiency; what matters is the amount of electricity generated per hour and the cost of storing it. If the payback of such a system plus installation is 12–18 months (without perverse subsidies from the govt to the homeowner), people start to invest in them in droves. If the cost stays where it is today, you have to have some sort of pyramid scheme like Elon Musk’s SolarCity to make it all work out (sort of). People don’t want to do that, because people don’t stay in their houses that long anymore.