Working planning tool
Make the assumptions visible.
Estimate storage energy for a constant AC load. Change the inputs, compare scenarios and download a plain-language brief.
Your scenario
Illustrative defaults. Replace them with your own assumptions.
Indicative nameplate energy
4.94 MWh
An energy estimate under your assumptions.
Energy delivered to the load4.00 MWh
Minimum continuous AC output1.00 MW
Additional energy margin0%
Based on 1 MW × 4 hours, 90% usable capacity and 90% discharge efficiency.
Save scenario A, then calculate another scenario to compare.
How the calculation works
Delivered energy = AC load × runtime.
Nameplate energy = delivered energy ÷ (usable fraction × discharge efficiency) × (1 + additional margin).
Percentages are converted to decimals. The efficiency input is one-way discharge efficiency, not round-trip efficiency. No prices or supplier data are used.
This constant-load calculation excludes auxiliaries, charging energy, degradation, temperature derating, redundancy and load transients. The output power shown is the load requirement, not a battery inverter selection. It is an educational scoping tool; a qualified project team must establish a detailed specification.