Energy Technologies
How to Size a Battery Energy Storage System
Battery sizing is not simply a question of how many MWh to buy. MW rating, discharge duration, cycle count, usable energy window and interconnection limits must be optimised together for the selected business case.
Start with the use case
Peak shaving, energy arbitrage, backup and frequency services require different power-duration profiles. One battery may stack multiple value streams, but overlapping reserve requirements need explicit modelling.
Losses and degradation
Round-trip efficiency, auxiliary loads, temperature, depth of discharge and C-rate affect usable energy. As capacity fades over time, warranty conditions and augmentation scenarios belong in the financial model.
Time-series simulation
Test candidate kW and kWh ratings with charge-discharge simulations over at least a year of load, generation and price data. Monthly averages hide peak duration, so use the most granular reliable interval available.
Sources
Related articles
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