[EE&C] Looking for sources on EE/renewable energy investment paybacks

[Ryan Dash]

Hello everyone,

It's good to see some activity in this group again.  I hope you all have been doing well.

I have a question that might be a little off topic, but somebody here may be able to help.  I'm doing a small project that will attempt to look at how investment in EE and renewable energy pays back in terms of energy output.  Obviously this is a huge topic with no firm answers; I'd like to give it just a cursory glance.  However, I'm having trouble finding sources to answer this.  Ideally I'd like sources that will make some educated guesses as to how much energy payback will eventually result from say, a billion dollars put into R&D on solar energy.  My searches on google and google scholar have not been very helpful, but I'm sure I'm just doing it wrong.

Thank you,
Ryan Dash