Sizing a commercial BESS
A battery energy storage system (BESS) for a commercial or industrial building is sized against the building's load profile and the use case.
Define the use case
Common use cases: peak shaving, load shifting (time-of-use arbitrage), backup power, and solar self-consumption. The use case sets the required power (kW) and duration (hours), which together give the energy (kWh).
Gather the load profile
Use the building's metered load data (ideally 15-minute interval data over a year) to find the peak demand and the periods you want to shift or back up.
Energy and power
Energy (kWh) = power (kW) × duration (h). Add margin for round-trip efficiency and depth-of-discharge limits. The system is then specified by rated energy (kWh), rated power (kW) and duration.
Safety and compliance
In India, the Central Electricity Authority (CEA) BESS safety framework takes effect from 1 April 2027. Any BESS should be specified against that framework, the applicable IEC standards (for example IEC 62619, IEC 62933), and the site's fire and electrical codes.
IONX ENERGY is the grid-tied BESS brand of Natraj Energy Limited. Contact us for a site assessment.