How this calculation works
Compute each appliance’s modeled energy, add other baseline use and charge each usage band at its entered marginal rate. Compare with the same bill without those listed appliances.
Appliance kWh = watts / 1,000 × hours/day × duty fraction × count × days; incremental bill = bill(base + appliances) − bill(base)A worked example
The example fans use 28.8 kWh and the fridge uses 32.4 kWh over 30 days. Adding 61.2 kWh to an 80 kWh baseline gives 141.2 kWh; the illustrative entered tariff yields a total bill of 932.82.
Good to know
User-entered bands, not an official state tariff. Not a slab-switching whole-bill rule. Tax applies to energy plus fixed charges; subsidy, minimum, demand and time-of-use rules are excluded.
Reference: US EIA: measuring electricity (opens in a new tab) ↗
Separate watts from energy
Power in watts is a rate, not a billable energy quantity. Divide by one thousand to get kilowatts, then multiply by modeled active hours to get kilowatt-hours.
The duty fraction further reduces the entered hours. If your hours already describe compressor-on time, applying a compressor duty fraction again would double count that reduction.
The battery recharge stage time calculator adds estimate staged recharge duration and reconcile input energy with stored energy, conversion loss and an active load across entered SOC segments.
Baseline use changes the marginal price
Other household use can already fill a cheap tariff band. Added appliances may therefore be charged partly or entirely at later rates even though their standalone consumption looks small.
The tool computes two complete bills and subtracts them. It does not multiply all extra energy by the first listed rate or silently replace a marginal-band model with a whole-usage slab rule.
Read the tax and fixed-charge convention
The same entered fixed charge appears in both comparison bills, so it cancels from the incremental difference when the rule is unchanged. The chosen tax percentage applies to energy charges plus that fixed charge.
Actual electricity bills can use materially different conventions. Enter a supported scenario from the current bill and keep discounts, demand charges, meter rules and taxes outside this model when they do not fit its stated assumptions.
Use the result with the next measurement
The VFD pump speed energy calculator estimates a separate speed-dependent electricity scenario. Its daily energy can inform a bill comparison, but its efficiency and hydraulic assumptions do not come from the tariff.
User-entered bands, not an official state tariff. Not a slab-switching whole-bill rule. Tax applies to energy plus fixed charges; subsidy, minimum, demand and time-of-use rules are excluded.
A few questions, answered
Does this fetch my electricity tariff?
No, all rate bands are entered.
Are the thresholds cumulative?
Yes, and final zero means unlimited.
Are operating hours and duty the same?
No, duty multiplies the entered hours; avoid counting reduced runtime twice.