For a very long time I’ve wanted to know how much is the charges if I use an electrical appliances such as my computer, air-conditioner, water heater and etc…
When I was very young, my mother used to tell me that air conditioner, water heater and iron consume a lot of electricity, and therefore, it’s expensive to use them. Even worst if you’ve forgotten to turn them off!
Every electrical appliance should have Watt (W).
This is the info that you need to calculate the usage of the electrical appliances that you use in hours.
Some doesn’t display Watt, but only Volt (V) and Ampere (A).
To get Watt, just multiple volt and ampere. Meaning, V x A = W or A x V = W. It’s the same.
In Malaysia, Tenaga Nasional Berhad(TNB) charges for home usage electricity is:
For the first 200 units per month: 0.218 cents
For the next 800 units per month: 0.258 cents
For each additional units per month: 0.278 cents
Formula to calculate electricity usage.
W x Hours / 1000 = kWh
Then first 200 kWh is used to multiply with 0.218, then the next 800 kWh multiply with 0.258.
Now you’ve got all the information that you need to calculate, let’s try calculating something.
If you use a Philips 14W bulb for 10 hours a day a month. How much is the charges?

14W x 10Hours / 1000 = 0.14 kWh
0.14kWh x 0.218(rate) = RM0.03052 per day
For a whole month, just multiply RM0.03052 with 30 because a month consist of 30 days.
RM0.03052 x 30 = RM0.9156
No wonder the Philips 14W bulb is called the Energy Saver. You’ll only need to pay less than a dollar if you turn on the light for 10 hours a day.
The calculation formula is the same thoughout the whole world, except for the Rates offered by their country’s electricy provider.
Let’s try another calculation.
You boil water everyday for one hour using Panasonic’s fast boiling with high power heater (2.4kW) kettle.
How much is the charges for the whole month?

2.4kW x 1hour = 2.4kWh
2.4kWh x RM0.218 = RM0.5232
For the whole month, RM0.5232 x 30 = RM15.696
It’s quite expensive to boil water everyday for an hour. But since this is a fast boiling with high power heater, I don’t think you’ll need an hour to boil water. I just gave an example of boiling water an hour for easy understanding and calculation.
Hope this information will help you determine to buy electrical appliances that don’t use so much energy.
Save energy = save money 😀