Peak Shaving
Peak Shaving is the dispatch of an on-site battery energy storage system or behind-the-meter solar-plus-storage plant during short intervals of maximum facility electrical load to cap peak kilowatt or megavolt-ampere demand drawn from the utility grid, reducing monthly capacity demand charges and avoiding costly upstream transformer or feeder upgrades.
How it is measured and specified
Commercial and industrial (C&I) utility tariffs typically bill large electricity users on two separate meters: volumetric energy consumption (measured in kilowatt-hours, kWh) and peak power demand (measured in kilowatts, kW, or kilovolt-amperes, kVA, averaged over a 15-minute or 30-minute billing interval). A single 15-minute spike caused by chiller startup, bottling lines, or harbor crane lifting can set the billing peak for the entire month or trigger a full-year capacity ratchet.
To shave a facility peak reliably, an energy storage system must be specified across two independent engineering axes: power conversion system (PCS) kilowatt rating (which determines the maximum height of the load spike the battery can clip) and usable energy storage duration in kilowatt-hours (which determines how many consecutive hours the system can hold the grid import below the target demand threshold without exhausting its depth of discharge).
How it matters when sourcing from China
When C&I buyers import Chinese LFP storage cabinets or containerized BESS—such as CATL EnerC, Sungrow PowerStack ST500CP, BYD Cube Pro, or Hanchu ESS outdoor cabinets—sizing the PCS-to-battery ratio (C-rate) around the site's actual load profile is critical. If the plateau of the facility's peak load lasts four hours but the buyer imports a 2-hour (0.5C) cabinet, the battery will deplete mid-window and fail to prevent the monthly demand charge. As highlighted in how battery and storage TCO is modelled, the site duty cycle governs both revenue capture and ten-year degradation.
Across Tradvolt's commercial storage studies, peak shaving frequently delivers the largest share of annual cash savings or stacks alongside time-of-use (TOU) arbitrage:
- In the 750 kWh / 250 kW EU bottling plant ESS TCO study, a 3-hour (0.33C) LFP cabinet charges overnight and discharges across the 14:00–19:00 weekday peak window on 260 operating days per year, shaving 150 kW of billing peak at a demand charge of €18.50/kW/month (€33,300/yr in demand-charge savings) alongside €17,154/yr in Year-1 TOU arbitrage.
- In the 3 MWh / 1.5 MW India harbor BESS TCO study, a 2-hour (0.5C) containerized LFP system stacks 1.0 MWh/day of peak shaving with 0.5 MWh/day of quay-crane regenerative energy capture and 0.5 MWh/day of cold-ironing shore power dispatch.
- In the 1 MWh / 500 kW Canada commercial peak-shaving LFP container study, a 20-foot container clips 380 kW of monthly billing demand ($14.50/kW-month) while shifting 810 kWh/day across a 300-day commercial operating schedule.
What to confirm before procurement
- Analyze at least 12 months of 15-minute utility interval meter data before selecting a 1-hour (1C), 2-hour (0.5C), or 3-to-4-hour (0.33C–0.25C) Chinese BESS configuration.
- Confirm that the Energy Management System (EMS) and external revenue-grade current transformers (CTs) at the point of common coupling are included in the supplier's scope and support closed-loop peak-shaving control.
- Account for annual battery capacity fade in your multi-year demand-shaving projection so Year-8 usable kilowatt-hours still cover the width of the peak load window.