Electricity Bill

1. Enter "power consumption (wattage of appliances and other devices)" and "hours of use per day".
2. "Electricity bill" and "power consumption" will be calculated automatically for each period.

• Electricity bill (yen) = Power consumption (kWh) x Unit price of electricity (yen/kWh)
• Power consumption (kWh) = Power consumption (W) x usage time (h)
• Electricity bill (yen) = Power consumption (W) x usage time (h) x unit price of power consumption (yen/kWh)
• Electricity bill for one day (yen) = Power consumption (W) x 24h x unit price of power consumption (yen/kWh)
• Electricity bill for one month (30 days) (yen) = Power consumption (W) x 24h x 30 days x unit price of power consumption (yen/kWh)
• Electricity bill for one year (365 days) (yen) = Power consumption (W) x 24h x 365 days x unit price of power consumption (yen/kWh)

Terms related to electricity bill calculation

• Power consumptionThe amount of power used by an electrical device to operate (W: watts)
• power consumptionThe amount of power used (kWh), calculated by multiplying the power by the time of use
• electricity billThe charge calculated by multiplying the amount of power consumed by the unit price of electricity (yen/kWh)
• wattage (W)The unit of power, the instantaneous amount of power used by the device
• kilowatt-hour (kWh)The amount of energy when 1,000 watts of power is used for one hour
• unit price of electricityThe cost of electricity per kWh (yen/kWh), also called the unit price of electricity
• time of use (h)The time the device was used
• energy amount (kWh)Indicates the actual amount of energy consumed, and 1 kWh is the amount of energy when a 1,000 watt device is used for one hour

How to check the unit price of electricity (yen/kWh)

This is the number you will use, as it is displayed on the official website of the power company you are currently or will be joining.

If you want to check without specifying a power company

Use the standard unit price of electricity as a reference<

• 31 yen per kWh *National Household Electrical Appliances Fair Trade Council

Points to note when checking the unit price of electricity

• Basic chargeSome power plans may have a basic charge. This is also added to your electricity bill.
• Step-up chargeIn a step-up charge system, the unit price varies depending on the amount of electricity used. The more you use, the higher the unit price becomes.
• Time-of-day chargeSome power companies have plans where the charge changes depending on the time of day (e.g., nighttime rates are cheaper).
• Seasonal chargeSome power companies have plans where the charge changes depending on the season (e.g., rates are cheaper in spring and autumn).

• National Fair Trade Council for Home Electrical Appliances

This tool is available for free.