Energy Equipment Life-Cycle Cost Calculator

How the energy equipment life-cycle cost calculator works

Each option begins with purchase and installation cash at time zero. Constant annual energy multiplies one shared energy rate, then annual maintenance is added. One entered replacement applies at its stated year only when that year lies in the study horizon; year zero means none. This is not an automatically repeated replacement cycle.

Residual cash reduces cost in the final year. Annual cash amounts and their discounted values round to cents by year, and initial cost is then combined with the discounted schedule. Both options use the same horizon and discount rate. Cost verdicts compare those rounded present totals, including a tie when the displayed totals are equal.

Enter comparable service boundaries and consistent currency-year assumptions. Inflation, financing, tax, equipment failure, tariff changes and replacement timing are not predicted. An assumed residual value is not a sale guarantee, and the lowest modeled present cost does not establish technical suitability.

Worked example

Over five zero-discount years at 0.20/kWh, A costs 1,000 initially, 250 each year, 300 replacement in year 3 and receives 100 residual: total 2,450. B costs 1,500 initially, 120 each year and receives 100 residual: total 2,000, or 450 lower. Raising B initial cost to 2,000 raises its total to 2,500 and makes the difference −50.

Sources and assumptions

The source material explains the underlying calculation or pricing structure. Entered prices, costs, schedules and scenario choices are your assumptions; this tool does not obtain supplier quotes or predict actual results.

• NIST: building life-cycle cost analysis