Peak shaving

Reserves a portion of battery capacity to cover demand spikes that exceed a configurable power threshold. Instead of the battery covering all household consumption, it holds back energy and only discharges to compensate the portion of demand above the peak limit — keeping capacity in reserve for when it is actually needed.

Behaviour without peak shaving

The PD controller covers all household consumption → the battery can fully discharge if consumption is high and sustained.

Behaviour with peak shaving active

When SOC is below the threshold: - The battery does not cover all consumption. - It only discharges to compensate the portion of consumption that exceeds the configured peak power limit.

battery_power = max(0, grid_consumption - peak_limit)

Example

Peak limit: 3,000 W
Current consumption: 4,500 W

Battery power = 4,500 - 3,000 = 1,500 W
Grid covers 3,000 W and the battery only 1,500 W

If consumption were 2,000 W (< limit), the battery would not discharge at all.

When to use it

Useful when: - The grid has a fixed cost per maximum contracted power and you want to limit peaks. - You want to ensure battery reserve for the night.