The Virtual Power Plant Storage Duration Estimator estimates how long an energy-limited resource can sustain a specified dispatch level. It divides usable energy by discharge power, after accounting for the user-entered usable energy value.
For a virtual power plant, the energy may come from aggregated batteries or other flexible assets. For demand response, this estimator is intended for storage-backed or otherwise energy-limited load reduction. It should not be applied to loads that can curtail indefinitely without an energy constraint.
Use energy that can actually be dispatched, after equipment limits and state-of-charge constraints.
Enter the MW level the portfolio is expected to sustain.
Reserve a portion of usable energy for uncertainty, minimum state of charge, or operational policy.
Compare the estimated hours with event duration requirements and asset operating limits.
The calculation assumes constant power over the dispatch period and no additional charging or load recovery during the event.
The result is the number of hours the entered energy can support the target power after reserving the selected margin.
Power limits, asset-level controls, temperature, degradation, and customer availability may reduce actual sustained duration.
Given: 48 MWh usable energy, 12 MW dispatch power, and a 10% reserve margin.
Calculation: Dispatchable energy = 48 × 0.90 = 43.2 MWh. Duration = 43.2 ÷ 12 = 3.6 hours.
Result: The portfolio can sustain the target for about 3.6 hours.
Enter usable energy available to the program. Nameplate energy may overstate duration because operating windows and reserve requirements reduce what can be dispatched.
It holds back part of the usable energy. This can cover uncertainty, minimum state of charge, or a reliability buffer.
Only when the resource has a meaningful energy limit. Thermostatic loads and process curtailment may require a different duration model.
Dispatch power may vary and assets can become unavailable. Efficiency, temperature, degradation, and control constraints also affect sustained output.
No. It estimates one continuous discharge or curtailment interval and does not model recharge or recovery between events.