Hey!

my favorite is PowerLedger https://coinmarketcap.com/currencies/power-ledger/

power ledger is one of the tokens that works towards a green cause!

they are working to make a marketplace of renewable energy

they are using the blockchain technology to automate market trading platform
so people can sell/buy energy that they saved and dont need to their neighbors in the price they choose

they plan to revolutionalize the worldwide energy industry
so people can buy energy from each others (that they got through solar pannels too) without any big buissness in the middle!