Just trying to understand where you are coming from: why do you need a blockchain (decentralized) based solution for something that generally doesn't really involve trust issues? You do state that the problem is people not being motivated to be less wasteful thus a incentive based system, but this can be done with any centralized service with the same extent of security and privacy really.
No, if you have a native token on your blockchain which works as an incentive for people to be less wasteful, you already have the answer to your question (besides many other aspects where blockchain has advantages). There needs to be a register that keeps track of the movements and number of token. Nobody should be able to artificially increase the supply.
