Grid-Scale Battery Energy Storage Systems worked example

Thermal Runaway Spacing with auxiliary hvac load per thermal runaway containment zone of 20 kW: a worked example

Push auxiliary hvac load per thermal runaway containment zone up to 20 kW and the picture changes. This example computes every intermediate figure at that operating point. Use it when sizing auxiliary load per thermal runaway containment zone and calculating the operating cost per MWh for each containment bay in a grid-scale BESS project.

The inputs for this scenario

  • Auxiliary HVAC load per thermal runaway containment zone: 20 kW (raised for this scenario; the documented default is 8)
  • Daily thermal monitoring and cooling hours: 24 hr (unchanged)
  • Site electricity rate: 0.09 $ / kWh (unchanged)
  • Usable MWh stored within the containment zone: 2 MWh (unchanged)

Working through the calculation

  • Applying the documented formula (Total zone thermal management cost per day = zone HVAC load x daily monitoring hours x site electricity rate) to the inputs above produces each figure below.
  • At this operating point the engine returns 480 kWh for auxiliary thermal management energy per day (kwh), the number this scenario is built around.
  • At this operating point the engine returns 43.2 $ for total zone thermal management cost per day.
  • At this operating point the engine returns 21.6 $ / piece for thermal management cost per mwh in containment zone.
  • At this operating point the engine returns 1.8 $ / hr for hourly zone thermal management cost.

How this compares with the baseline

  • Against the tool's baseline example, where auxiliary hvac load per thermal runaway containment zone sits at 8 kW and the headline result is 192 kWh, this scenario comes in 150% above the baseline at 480 kWh.
  • It computes the daily auxiliary energy and operating cost of thermal management for one BESS containment zone, and the resulting thermal management cost per MWh stored. The value of this scenario is the size of the gap it exposes: that gap, priced out over a year, is the budget you can justify spending to close it.

Results at a glance

  • Auxiliary thermal management energy per day (kWh): 480 kWh (headline result)
  • Total zone thermal management cost per day: 43.2 $
  • Thermal management cost per MWh in containment zone: 21.6 $ / piece
  • Hourly zone thermal management cost: 1.8 $ / hr

Run it with your numbers

  • Every input above is editable in the live Thermal Runaway Spacing calculator, which recalculates instantly and can be shared with the inputs intact.

Last reviewed 2026-05-12.