One of the main criticisms of cryptocurrencies is that they consume a lot of energy and are therefore not sustainable. But all blockchains are not created equal and there are different ways in which transactions on a blockchain can be validated.

Bitcoin and Ethereum use something known as "proof of work" (though Ethereum plans to change this sometime next year). This method of validation does indeed use quite a bit of energy.

But another way to validate and maintain security on a network is through something known as "proof of stake." This is what Solana and many other blockchains are now using. Put differently, there's no "mining" required, which is the work that is so energy intensive.

To demonstrate the difference, the Solana Foundation recently published this comparison chart: