How does a site battery plan its day?

From a demand forecast, the grid limit and the day's prices, hour by hour, with four rules in order: never below the floor, cover the peak, keep the reserve for the next peak, then follow the price. The deep dive shows one day's plan.

Explained in

Battery storage · Deep diveThe battery's day plan, as the controller wrote itThe energy management system's plan for the Thursday of this path: demand, grid, battery and state of charge hour by hour, the price of each hour and the rule the controller applied.
  • Never below the floor. 10% stays in the battery whatever happens; the plan's lowest point is 32%.
  • Cover the peak. Whenever the chargers need more than the connection, the battery supplies the difference; this is why the site exists (stop 01).
  • Keep the reserve. Refill before the next expected peak, even at a high price. Hours 14, 15 and 19 are this rule.
  • Then follow the price. With the reserve safe, wait for the cheap hours: 21 and 22 wait, 23 refills.
From “The four rules, in the order they win”, stop 08
  1. Why do some fast chargers have a battery?Peaks of demand are short. A battery charges slowly from a small grid connection and discharges quickly into cars, so a site can offer high power where the grid cannot yet.
  2. Are battery storage systems safe?EU law requires stationary systems to be tested for the safety parameters of Annex V of the Batteries Regulation, ten tests from thermal shock to fire, with the emission of gases considered throughout, and to document further hazards and their mitigation.
  3. What is a battery passport?From 18 February 2027, EV batteries and industrial batteries above 2 kWh need an electronic record with information on the model and the individual battery.