Battery-Supported EV Charging ROI
Estimate annual peak-demand savings and payback when a battery energy storage system (BESS) is paired with depot or destination DC charging. Indicative only — talk to us for a site-specific model.
BESS & Supply Upgrade Capex
Combined cost for transformer & switchboard upgrade — used as the baseline alternative to the BESS.
Total cost incl. hardware, installation, switchboard works, civil and integration.
BESS Specification
Total usable storage capacity.
Max discharge power; caps demand reduction potential.
Overall charge + discharge efficiency.
Equivalent full cycles per day (1.0 = one charge / discharge).
Ongoing maintenance, inspections & service contracts.
Projection horizon — expected operating life of the BESS.
Average yearly capacity loss. Typically 1–3% for LFP and 0.5–1% for LMFP.
EV Load Profile
Combined connected EV charger capacity.
Total energy dispensed per day across all chargers.
AC/DC conversion, cable and charger losses.
Tariffs
Delivered energy cost during peak periods.
Delivered energy cost during off-peak periods.
Opportunity cost of using solar to charge the BESS rather than exporting.
Network demand charge based on maximum kVA demand.
Approximate kVA reduction in EV-related peak demand achievable with the BESS.
Finance
Used for the simple NPV estimate of BESS savings.
Results
Adjust the inputs and click Calculate to see annual running costs, lifetime savings, and energy mix charts.