Dare I chime in again?
GDP is a PRODUCT.
Debt and credit with interest are the impellers of circulation, hence currency and in big-project investment. Stagnation without flow gives you no big projects/technology/developments.
Energy is always going to be used. It's only different in scale.
Interest is the cost of doing business. If you're averse to interest, you're averse to doing business. Believers in self-sufficiency wind up like Myanmar or Haiti.
I assert that interest and inflation are divorced from each other; left unchecked by regulation, inflation will also give you Myanmar or Haiti or Argentina or Russia or.....etc etc etc.