Microgrid & Distributed Energy Equipment calculator

Microgrid Capacity Gap Calculator

Microgrid Capacity Gap quantifies the difference between the energy a battery or DER fleet can theoretically dispatch and what it can actually deliver after availability downtime and round-trip efficiency losses. Microgrid designers and energy managers use it to size storage honestly against a load or a grid-services commitment, instead of trusting nameplate kWh. It starts from usable energy per dispatch interval and the number of intervals, then derates for the fraction of time the asset is actually online and the energy lost charging and discharging. The gap between gross and deliverable capacity is exactly the shortfall you must cover with more storage or a tighter dispatch plan.

What this calculator does

  • Estimate the usable energy a microgrid can deliver across dispatch intervals, after availability and round-trip efficiency, so resilience planners can compare it against peak load and see the capacity gap.
  • Use it when a microgrid is asked to carry more critical load and you need to know whether deliverable capacity covers peak demand.
  • It computes gross dispatchable energy, then derates it by asset availability and round-trip efficiency to return deliverable capacity in kWh and the losses that create the gap.

Formula used

  • Gross microgrid capacity = usable energy per dispatch interval × available dispatch intervals
  • Deliverable microgrid capacity = gross capacity × asset availability × round-trip efficiency

Inputs explained

  • Usable energy delivered per dispatch interval:
  • Number of available dispatch intervals:
  • Asset availability:
  • Battery round-trip efficiency:

How to use the result

  • Use it when sizing storage or validating a dispatch or demand-response commitment against realistic, derated energy rather than nameplate.
  • It applies flat availability and efficiency factors; it does not model state-of-charge limits, depth-of-discharge derating, or temperature effects that vary interval to interval.

Current U.S. benchmarks

  • Industrial electricity averages 8.66 cents per kWh across the U.S. (EIA, Apr 2026), up 5.5% from a year earlier. Energy-intensive steps carry this directly into unit cost.
  • Steel mill PPI stands at 348.53 (BLS, May 2026), up 6.7% from a year earlier. New factory orders are up 2.3% year over year (Census).

Common questions

  • How do you calculate deliverable microgrid capacity? Multiply usable energy per interval by the number of intervals for gross capacity, then multiply by availability and round-trip efficiency. Here 4 x 480 = 1,920 kWh gross, derated to 1,676.16 kWh deliverable.
  • What is the microgrid capacity gap in the example? Gross capacity is 1,920 kWh and deliverable is 1,676.16 kWh, so the gap is about 244 kWh — 192 kWh lost to availability and 51.84 kWh to round-trip efficiency.
  • Why does round-trip efficiency reduce deliverable energy? Every charge-discharge cycle loses energy to conversion and resistive heating. At 97% round-trip efficiency you only get 97% of what you put in back out, which trims deliverable kWh.
  • What is a good round-trip efficiency for a microgrid battery? Modern lithium-ion systems land around 85-95% AC round-trip including the inverter; the 97% in the example is on the optimistic, DC-leaning end.
  • How is this different from nameplate capacity? Nameplate ignores downtime and conversion losses. The capacity gap derates nameplate by real availability and efficiency so you size storage against energy you can actually dispatch.

Last reviewed 2026-05-12.