Bitcoin, the most popular cryptocurrency, consumes 20 tera watts hour (Twh) per year just to maintain the network, and this comsumption is increasing every day, which. See https://digiconomist.net/bitcoin-energy-consumption
More generally, all proof of work (PoW) coins require heavy computations to avoid attacks against their network.

The solution: Other coins, like Bitconnect or RISE have a solution to this problem, they have a consensus protocol that does not require computations: the consensus is based on the people owning the biggest shares (Proof of Stake, PoS or Delegated Proof of Stake, DPoS) Coins. These coins are called Proof of Stake (PoS) or Delegated Proof of Stake (DPoS), they are the future: decentralized and eco-friendly.

If you want to help governments to understand that PoW mining is bad for the environment, please sign this petition: https://www.thepetitionsite.com/takeaction/844/861/035/