The short answer
Divide pence or cents per kWh by 100 to enter pounds, dollars or euros per kWh. For example, 20 US cents/kWh becomes 0.20 USD/kWh. This changes the currency unit, not the energy unit or exchange rate; selecting a currency does not convert an existing price.
The price input uses a major currency unit
Enter pounds, dollars or euros per kWh. When your tariff is written in pence or cents, divide its numerical price by 100.
The electricity unit kWh stays the same. This is a currency-unit conversion, not a conversion of power or energy.
| Tariff wording | Currency | Price to enter |
|---|---|---|
| 28 pence per kWh | GBP | 0.28 |
| 20 US cents per kWh | USD | 0.20 |
| 30 euro cents per kWh | EUR | 0.30 |
| £0.28 per kWh | GBP | 0.28, already converted |
The values are illustrative. Use the actual rate and its stated billing basis.
Why entering 28 instead of 0.28 matters
Imagine a compatible cycle-energy figure of 0.50 kWh. At £0.28/kWh, the cycle costs £0.14. At £28/kWh, it costs £14.00.
The second result is 100 times larger because the input states a price 100 times larger. A large result does not automatically mean the appliance is inefficient; first check the tariff unit.
Likewise, do not divide a rate twice. A printed dollar rate of $0.20 is already in dollars. Entering 0.002 would understate the price by a factor of 100.
Check the energy unit independently
There are two separate unit decisions. The rate may need converting from cents, while a consumption figure may need converting from kWh per 100 cycles.
With 50 kWh per 100 cycles and 28 pence per kWh:
(50 ÷ 100) × (28 ÷ 100) = £0.14 per cycle
At four cycles per week across 52 weeks, that is 104 kWh/year and £29.12/year. Enter 50 with the per-100-cycle basis selected, and 0.28 as the price. The calculator performs the energy division itself.
A quick result check
Ask whether the number describes one kWh or one cycle. A cycle using less than one kWh should cost less than the entered price of one kWh, provided both quantities use the same scope.
Read where to find your tariff and what per 100 cycles means. Then estimate a washing-machine cost using the correctly stated inputs.