10 Air-Con Tips to Use Less Electricity So We Can Sleep With Air-Con At Night


Last Updated on 2022-09-17 , 8:16 pm

We can’t live without our air-conditioner. Yet, at the same time, we can’t live on an empty stomach.

So what’s the solution?

Find a way to reduce your electricity bills and still enjoy the air-con, of course.

Luckily for you, I have some air-con hacks.

But to start us off, let’s learn the basics.

1. Know what is energy efficiency ratio (EER)

This is going to get quite technical so I’m going to break them up for us to comprehend. The EER is this ratio:

Cooling capacity (in British thermal units [Btu] per hour): power input (in watts).

But what you really need to know is this: The higher the EER rating, the more efficient the air-con in terms of long-term costs.

But you will have to pay a higher price when you buy it.

So the next time you go air-con shopping, you can question the salesperson and make sure you don’t fall for the sales talk but the EER facts instead.

2. Effect of EER on my electricity bills

Most air-cons made after the year 2000 have an EER of at least 9.7.

But one that receives an Energy Efficiency rating has an EER of at least 10.7.

“Huh, but only one point difference? Will affect the bill meh?”

Yes, it does.

In fact, an increase in EER by one point can save you up to 10% on your electricity bill. That’s $10 for every $100 bill. I can buy at least two plates of Char Kway Teow already!


3. What’re British thermal units (BTU)?

“So if cooling capacity is measured in BTU… eh, wait, what is BTU again?”

You need to choose a BTU level according to the size of the room you plan to cool. The right BTU level will get you a comfortable cool temperature without the sky-high bills.

Here’s a general rule to follow: An air conditioner generally needs 20 BTU for each square foot of living space.

So the last thing you want to do is to buy an oversized unit that performs less efficiently than a properly-sized unit.

4. How much BTU do I need?

“Okay… very cheem leh. So how to do the calculations?”


According to Gain City, here’s their guide for you:

Find the square footage of the room you are trying to cool and multiply by 35. We shall call this ballpark figure, X.

If it’s generally a shady room, decrease X by 10%.

If you have a room facing the sun most of the time, increase X by 10%.

More than two people will be in the room regularly? Add 600 BTUs per person to X.

In the event that you’re putting the air-con in the kitchen, please add 4,000 BTUs to X.


5. Request for the best grade of insulation tubing

If you’ve bought aircon for your house before, you’ll always have the salesperson throwing in better insulation tubes as an incentive.

And most of the time, you don’t even know it’s a big deal.

The insulation tubing in your system carries the Freon gas to and fro the compressor to the Fan Coil Unit (FCU). So, it’s important to prevent energy losses through broken or faulty insulation.

With faulty insulation comes greater use of electricity because there’s energy loss mah. Make sure you tell your installer that you want the best of the best grades.

So you can avoid incurring unnecessary long-term costs.


6. Keep up with servicing or maintenance

There is no fixed number of times you should call for professional maintenance. Just look out for these symptoms because they are telltale signs:

  • Leakage or lessened air-flow
  • Making unnecessary excessive noises
  • Taking a longer-than-usual time to cool the room
  • An energy-saving aircon that runs continually
  • Your air-con turns on and off very frequently (and we’re not talking about self-regulating ones)

“Huh? I’m not saving money now but spending more to maintain leh. Are you kidding me?”

Think long-term, my friends.

If these symptoms are left unchecked, energy is lost and you’re actually paying higher bills because your air-con is ‘working harder’ (using more electricity) to counter the problems.

7. Opt for ‘Dry Mode’ than ‘Cool Mode’

‘Dry Mode’ is usually distinguishable by a teardrop icon while the snowflake icon depicts the ‘Cool Mode’.

Here’s what the teardrop icon does: it sucks out the moisture from an extremely humid room and returns dry air via the unit’s fans to regulate the room’s humidity (level of water vapour in the atmosphere).

Most importantly, it saves a lot of power than compared to ‘Cool Mode’, which is heavily reliant on the unit’s compressor to bring about significant cooling.

I.e the type of cold that makes you bury yourself underneath the blanket.


But still, too much of dry air isn’t a good thing. You don’t want to feel like you’re living in an aeroplane-like environment. So keep ‘Dry Mode’ on for a couple of hours then switch to the other modes accordingly.

8. Reduce the temperature slowly

Are you guilty of reaching home, rushing to reach the remote controller and pressing your thumb on the ‘down’ arrow repeatedly?

You’re not alone. But here’s why you should stop.

Your air-con will need to work extra hard (use more energy) in order to cool your room if you do that.

By now, you should know that using more energy equates to an even higher bill, don’t you?

So take it slow, reduce the temperature gradually and let your body be accustomed to the change.

9. Optimum Temperature

Actually, you don’t have to make your room feel cold like an igloo because, in Singapore, that’s called wasting energy or like our parents call it, “浪费电”.

Remember golden 25, the number that indicates you’ve lived a quarter century. Sorry for digressing but in this case, we’re of course talking about golden 25 in terms of degree Celsius.

It is more than enough to make most homes cool and remove the humidity.

If you find yourself sleeping under a thick comforter, then you know the temperature isn’t optimal. Yeah, it sure feels good to create a make-believe winter but you will probably flip when you see the bill.

10. Make friends with the fan & timer

This is what I’ve personally done so my parents won’t complain at the end of the month. I turn on the air-con and the fan at the same time.

“Siao ah, waste more electricity like that!”

Aiyo, I’m not asking you to blast your air-con at high speed and at 16 degree Celsius.

Keep it at 25 degree Celsius (‘Cool Mode’ and a lower temperature if you prefer) and set the timer for about 2 to 3 hours. Do it with your fan on.

Sometimes I’ll open the windows a little for ventilation so when the air-con turns off after 3 hours, I won’t die of suffocation. Try it and let us know if it works!

But really, it’s best to reduce reliance on air-con. Research has shown that it takes 21 days to form a new habit.

Just give yourself 3 weeks without sleeping with air-conditioning and you will probably do it for the rest of your life! I’m sure your bank account will thank you.

The earth will, too.

To learn how cool your room without having to spend a bomb on air-conditioner, check out this video:

(Check out our YouTube channel for more informative and entertaining videos!)

Featured Image: Seasontime / Shutterstock.com