Find out which appliances are inflating your electricity bill.
The electricity bill arrives and the amount doesn't match the feeling that you didn't use much. The explanation almost never lies in what you remember turning on — it's in... three or four devices that consume energy silently, some of them 24 hours a day.
You can find out exactly how much each appliance costs per month, using only its power rating and the kWh price printed on your bill. It's a two-minute calculation, and after that, the bill is no longer a mystery.
Air conditioning leads
A window unit draws between 1,000 and 1,500 watts when switched on. Eight hours a day in the summer translates to hundreds of kilowatt-hours per month.
The shower is the invisible villain.
Between 4,000 and 8,000 watts, the highest power rating in the house. In many homes, it alone accounts for a huge chunk of the bill.
What is spent while standing still?
An appliance in standby mode continues to draw power. Added together, those little red dots in the house cost more than they seem.
The account that you make yourself
Power multiplied by hours of use, divided by a thousand, multiplied by the price per kWh. That's all it takes — and it settles the debate about who's spending the most.
Why did the bill go up even though I didn't change anything?
In addition to consumption, there is the price. The regulatory agency projected an average increase of around 8% in tariffs for 2026, and the price per kWh also changes according to the tariff flag of the month and the distributor in your region — the difference between the most expensive and the cheapest in the country exceeds twenty cents per kWh.
In other words, two neighbors from different states, with the same consumption, pay very different bills. That's why the only calculation that matters is done using your bill number.
What can still be done this month?
Adjustments that are worth money.
Two degrees higher on the air conditioning and five minutes less in the shower will show up on your next bill.
Read the label before buying.
An efficient device costs more in the store and less every month. This guide shows you how to truly compare them.
Find your villain.
Each household has one. With the bill in hand, you can identify yours in a few minutes.
Common questions
It depends on power consumption multiplied by usage time. The shower has the highest power consumption; the refrigerator is left on all year round. The guide compares the two in reais (Brazilian currency).
On your electricity bill itself, in the section detailing your consumption. That's the number you use in the calculation — not an average from the internet.
It's done on a device that's on standby. It's not the most economical, but it's the easiest to do right now.
It's usually worthwhile when the model is quite old, because the difference in fuel consumption is significant and pays for itself over the years. The guide shows how to do this calculation.
The guide to the side provides a table for each appliance, showing power consumption, estimated monthly usage, and cost in reais — as well as step-by-step instructions for calculating this using the numbers from your bill.
Open the full consumption table