Blockchain is a slow, cumbersome, badly designed database that is incredibly energy and material intense to run.
1 single bitcoin transaction:
712.41 kgCO2: carbon footprint of 1,578,956 VISA transactions,
1277.28 kWh of electricity: power consumption of an average U.S. household over 43.78 days
351.20 grams of e-waste: equivalent to the weight of 2.14 iPhones 12
20,130 liters of water: amount of water in a backyard swimming pool.

(from https://mastodon.green/@gerrymcgovern/114358482342749909)