HVAC and refrigeration
Refrigeration door heater energy cost
Price measured anti-sweat heater duty cycle and an alternate schedule.
Your inputs
Complete the fields for your selected method. Zero means intentionally zero, not unknown. Currency selection labels amounts; it does not convert exchange rates.
How this calculation works
rated kW*schedule hours*duty*rate, before vs after. Metered alternative: annual heater cost = heater-only annual kWh × price.
Duty is applied to power × enabled hours, never to metered kWh. Enter approved schedules; this does not prescribe humidity controls or anti-sweat settings.
What information do I need?
Use records for the same job, equipment or accounting period. Only the fields for your selected entry method are required. An unknown amount is not zero.
Input definitions and where to find them
- How do you know the energy use?: Choose the information you actually have. Only the selected method is required.
- Measured or rated door-heater input when on (kW): Measured or qualified supplier/assessment value for measured or rated door-heater input when on at the SAME operating point. Do not infer equipment sizing, safe limits or missing engineering data. Used with: Measured input power and operating schedule.
- Existing annual enabled schedule (hours/year): Use matching records or a clearly identified owner assumption for existing annual enabled schedule, in the displayed unit and the stated row/period scope. Used with: Measured input power and operating schedule.
- Existing on-duty fraction during schedule (%): Observed on-hours ÷ existing enabled hours ×100. Used with: Measured input power and operating schedule.
- Alternate annual enabled schedule (hours/year): Use matching records or a clearly identified owner assumption for alternate annual enabled schedule, in the displayed unit and the stated row/period scope. Used with: Measured input power and operating schedule.
- Alternate on-duty fraction during schedule (%): Supplied on-fraction for alternate schedule, not prescribed control settings. Used with: Measured input power and operating schedule.
- Electricity price per kWh (selected currency): Matching energy/volumetric tariff or bill component for electricity price per kwh, excluding fixed charges or other charges not modeled.
- Existing annual door-heater energy (kWh): Use an isolated record or clearly labeled estimate matching this field and period. Do not substitute an unrelated whole-site total. Used with: Metered or separately estimated kWh.
- Alternate annual door-heater energy (kWh): Use an isolated record or clearly labeled estimate matching this field and period. Do not substitute an unrelated whole-site total. Used with: Metered or separately estimated kWh.
Use the Where to find this value controls beside the inputs for available work-it-out helpers. Estimates remain your assumptions; a helper does not verify the source figures.
Worked example
Example amounts use US dollars (USD).
Example answer: Existing annual heater cost is $657.00 for the illustrative inputs below.
Example inputs
- How do you know the energy use?: Measured input power and operating schedule
- Measured or rated door-heater input when on: 0.50 kW
- Existing annual enabled schedule: 8,760.00 hours/year
- Existing on-duty fraction during schedule: 100.00 %
- Alternate annual enabled schedule: 4,380.00 hours/year
- Alternate on-duty fraction during schedule: 50.00 %
- Electricity price per kWh: $0.15
- Existing annual heater cost
- $657.00
- Alternate annual heater cost
- $164.25
- Annual modeled savings
- $492.75
- Annual energy reduction
- 3,285.00 kWh/year
These illustrative values are not recommended rates or industry averages. Replace every example input with your own figures.
Use the result well
Price measured anti-sweat heater duty cycle and an alternate schedule.
Keep inputs on the same scope and time basis. Calculations retain precision internally; displayed values generally round to two decimal places, with extra precision for very small values and whole-unit rounding where required. Economic comparisons describe your supplied assumptions and do not guarantee future results.
This tool provides business arithmetic. It does not approve engineering designs, establish legal or tax treatment, select equipment or certify safe operating conditions.