Energy cost calculator
Power, hours per day, days and price per kWh: you get energy used and its cost — handy for charging equipment power on a job.
Purchase quantity
180 kWh
Net measurement: 180 kWh
- Energy used180 kWh · $27.00
- Daily use6 kWh
Indicative estimate: $27.00
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How it's calculated (visible formula)
kWh = power (kW) × hours per day × days; cost = kWh × rate
- Net geometric measurement, no waste.
- Adjustable waste % for cuts and breakage.
- Purchase rounded up to sellable units (boxes, bags, buckets, boards).
How to calculate it, step by step
- Find the appliance wattage.
- Estimate real run hours per day.
- Enter the number of days.
- kWh = kW × hours × days.
- Multiply by your rate per kWh.
Worked example: 2,000 W dehumidifier, 3 h a day for 30 days
- 2 kW × 3 h × 30 = 180 kWh
- 180 × $0.15 = $27
→ $27 for the month.
Common mistakes
- Using peak wattage for cycling appliances.
- Forgetting fixed monthly charges.
- Mixing up W and kW.
Pro tips
- For cycling appliances, use actual run hours.
- Bill equipment power on long jobs.
- Shift loads to off-peak hours on time-of-use plans.
- Use a plug-in meter if unsure.
From calculation to quote
Add labour, overhead and your margin, and generate the professional PDF.
FAQs
- How much does a 1,500 W heater cost per hour?
- 1.5 kWh × your rate — about $0.23 at $0.15/kWh.
- What rate should I use?
- The per-kWh energy charge on your bill, plus taxes for the final cost.
- Cycling appliances?
- Use actual run hours, not hours plugged in.
- How much does a central AC use?
- A 3-ton unit draws roughly 3–3.5 kW while running.
- How much does a fridge use per month?
- About 30–60 kWh depending on size and age.
- What are fixed charges?
- Monthly fees independent of usage.
Sources and standards
Maintained by Srikanta M · Formula v1.0.0 · Verified 2026-09-10 · Updated 2026-09-10 · Limits: quantity estimation, not structural design or site supervision.