Information is sharded and held locally instead of globally. The DHt and local chains replaces the blockchain model.
Holochain itself has no currency, so in that way its existence doesn't require almost 1% of the world's coal and oil energy output just to continue operating (as btc currently does).
Currencies built on top of Holochain, like Holofuel, are designed to be mutual credit cryptocurrencies that don't have any mining. The energy consumption of hosting on Holo.host will be similiar to the energy you use to run your desktop computer all the time anyway.