How an appliance's usage is calculated
CFE bills electricity in kilowatt-hours (kWh). To know how many an appliance uses, multiply its watts by the hours it is on and divide by 1,000. A mini-split of 1,100 W running 7 hours uses 7.7 kWh a day, about 470 kWh per two-month bill.
The watts are on the appliance's label or in its manual. The ones in this calculator come from CFE's table (and FIDE's for some appliances): use them as a starting point and change them to yours.
The appliances that use the most
In almost every home the top spots are the same: the air conditioner or mini-split, the refrigerator (especially an old one) and appliances that heat, like the clothes dryer or an electric oven. And since CFE bills by tiers, turning off the biggest one lowers the bill more than its share of the kWh suggests.
That is why the “if you turn it off” column is the most useful one: it tells you in pesos how much each change is worth.
CFE's tips to use less
- Air conditioning at 25 °C (77 °F). Each degree lower raises its usage 4 to 6 %.
- Keep the fridge away from heat (stove, oven, windows) and at the temperature the manufacturer recommends: each extra degree of cold raises its usage 5 %.
- LED bulbs instead of incandescent: they save more than 80 % of the energy and last more than 10,000 hours.
- Line-dry clothes when you can instead of using the dryer.
- Unplug what you don't use: devices that are off but plugged in still use power.
Source: CFE, press release CFE-BP-72/23 (June 15, 2023).
Frequently asked questions
How do you calculate how much electricity an appliance uses?
Multiply the appliance's watts by the hours it is on and divide by 1,000 to get kWh, the unit CFE bills. For example, a 1,100 W mini-split used 7 hours uses 7.7 kWh a day.
How much electricity does a mini-split use?
According to CFE's table, a 1-ton mini-split draws 1,100 W and a 2-ton one 2,200 W. Used 7 hours a day, the 1-ton unit uses about 234 kWh a month. It is one of the appliances that raises bills the most in hot months.
How much electricity does a refrigerator use?
It depends a lot on its age. An 11 ft³ refrigerator with an energy label uses about 385 kWh a year, according to FIDE; an old one, with CFE's data (400 W and 8 hours a day of compressor time), reaches about 1,170 kWh a year.
What is standby power?
It's what TVs, chargers, cable boxes and other devices use while off but plugged in. CFE estimates about 20 watts all day for a home, around 14 kWh a month. Unplugging them or using a power strip with a switch cuts it.
Why doesn't the result match my bill exactly?
Because hours of use are estimates and each appliance's real usage depends on its model, age and the weather. If you enter the kWh from your bill, we tell you how much of it your list explains; what's missing is usually a forgotten appliance or one used more than you think.
Appliance data: CFE, press release CFE-BP-72/23; FIDE, “¿Sabes cuánto gastan?”.
Learn more: Which appliances use the most electricity? · CFE electricity rates