Found but not yet verified; "Germany is paying households to charge their EVs at night — and using 4 million car batteries as a single giant grid storage asset. The concept is called Vehicle-to-Grid, and Germany is deploying it at a scale that makes every previous trial look like a proof of concept. Under Germany's amended Energy Industry Act, EV owners can register their vehicle's battery as a grid asset — allowing the grid operator to draw power from the car during peak demand periods and charge it during surplus periods, automatically, without driver involvement. In exchange, the owner receives payments that offset a significant portion of their electricity costs. Volkswagen's bidirectional charging system — deployed across its ID. series vehicles from 2023 — supports up to 11 kilowatts of Vehicle-to-Grid discharge. A single ID.4 with a 77-kilowatt-hour battery can discharge enough electricity to power an average German home for three days. Four million such vehicles — the number of EVs on German roads by 2025 — represent a theoretical grid storage asset of 308,000 megawatt-hours. That is more storage than all of Germany's dedicated grid-scale battery installations combined, distributed across the country, plugged in every night when electricity demand is lowest and renewables are most abundant. The economics compound the physics. German EV owners who participate in Vehicle-to-Grid schemes buy electricity at off-peak rates — as low as €0.08 per kilowatt-hour at night — and sell it back during peak periods at rates that can reach €0.35 per kilowatt-hour. The car earns money while the owner sleeps. The grid gets storage it did not have to build. The renewable energy that would otherwise be curtailed finds a use. Every party in the transaction wins simultaneously. Germany is not building a battery storage network. It is discovering that it already has one, parked in 4 million driveways. Source: Bundesnetzagentur — Vehicle-to-Grid Implementation Framework Report 2023