There's an interesting project called Solar Coin[0] attempting to do this. I'm not too sure how it relates to crypto-currency, though. [0] https://solarcoin.org

There's an interesting project called Solar Coin[0] attempting to do this. I'm not too sure how it relates to crypto-currency, though. [0] https://solarcoin.org/en/front-page/ https://solarcoin.org/en/front-page/