Model consumption and demand separately
A deployment operating below its eventual IT capacity may consume less energy while still facing demand-based obligations. A contractual floor or ratchet must be modelled from its actual wording. Average utilisation is not automatically the correct basis for the demand charge.
Show the denominator
Recurring effective $/MWh is the recurring electricity bill divided by metered MWh. At zero consumption that ratio is undefined, even if a demand bill remains. Cost per utilised IT kW-month uses a different denominator and should be named explicitly. Neither measure should silently absorb refundable deposits.
Build the monthly ramp
Use each month’s IT load, PUE assumption, hours, utilisation and billable demand. Sum those monthly bills for an annual total. Keep one-offs, deposits, riders and unmodelled obligations alongside the calculation so readers know what the result includes.
Take this checklist into the next meeting
- Obtain the measured, contracted and ratchet demand rules.
- Keep utilisation separate from peak demand.
- Check zero-load and slow-ramp cases.
- Reconcile the 12 monthly bills before quoting annual cost.
Evidence and assumptions
This guide develops the supplied buyer-side research framework. It makes no site-specific capacity claim. Obtain current utility documents, manufacturer specifications and appointed professional advice for the actual project. Any numerical examples are worked examples, not project data.