Btc uses a lot of energy...that is true....it is also the reason many of the miners are converting over to renewable energy to power their operations. China is a big user of solar and that is where many of the mining operations are located.

As for the difference, blockchain is the underlying technology. That is a decentralized, public ledger. Tokens are nothing more than an app built on the blockchain, like Steemit is. Bitcoin is a blockchain...as is Eth...as is steem...they are all separate blockchains with their own token.