I just installed my first Aircon 3 weeks ago. A 9000btu inverter in my bedroom. For health reasons it's best I maintain  temperature of 21c. My bedroom is 18sqm so 9000 btu is perfect. My bill is in a Thai name and she is currently unable to be contacted..However to work out my monthly cost what could be easier simply deduct last months bill for my new reading and it should give me a good idea of how much extra I can expect to pay per month....only one problem for the first time in 2years my electric bill has not turned up and it was due in my post box a week ago. Now I have no way of contacting them to complain because I don't have any old bills and I don't know my house address... luckily I can pay it next month when my next bill arrives...if it does arrive...only in Thailand😸

1 hour ago, Tanlic said:

I just installed my first Aircon 3 weeks ago. A 9000btu inverter in my bedroom. For health reasons it's best I maintain  temperature of 21c. My bedroom is 18sqm so 9000 btu is perfect. My bill is in a Thai name and she is currently unable to be contacted..However to work out my monthly cost what could be easier simply deduct last months bill for my new reading and it should give me a good idea of how much extra I can expect to pay per month....only one problem for the first time in 2years my electric bill has not turned up and it was due in my post box a week ago. Now I have no way of contacting them to complain because I don't have any old bills and I don't know my house address... luckily I can pay it next month when my next bill arrives...if it does arrive...only in Thailand😸

 

Since we don't really want to resurrect an 8-year-old thread, here's a new one 🙂 

 

Do you have access to your meter?

If so, it will have a reference number which you can take to your local MEA/PEA office and they should be able to tell you what you owe.

 

Your 9,000 BTU A/C will use about 900W when working hard, normally one assumes that a correctly sized unit will run at about 30%, so 300Wh (0.3kWh) per hour of use.

 

Of course, total energy consumption is very much dependent upon the weather, you may find your unit struggles to maintain 21C during the warmer months.

 

 

1 hour ago, Tanlic said:

I just installed my first Aircon 3 weeks ago. A 9000btu inverter in my bedroom. For health reasons it's best I maintain  temperature of 21c. My bedroom is 18sqm so 9000 btu is perfect. My bill is in a Thai name and she is currently unable to be contacted..However to work out my monthly cost what could be easier simply deduct last months bill for my new reading and it should give me a good idea of how much extra I can expect to pay per month....only one problem for the first time in 2years my electric bill has not turned up and it was due in my post box a week ago. Now I have no way of contacting them to complain because I don't have any old bills and I don't know my house address... luckily I can pay it next month when my next bill arrives...if it does arrive...only in Thailand😸

So you have no old Bill and don't know your address? Hope you still can remember your own name.

 

If you had any details you can see your Bills for the last six month regardless if they have arrived by mail.

 

https://www.pea.co.th/en/our-services/bill-history

Roughly 1000 per unit here in Phuket

My monthly bill is 1200 bht once a guest arrives and uses the 2nd AC its 2200 

For what it is worth it is loss of cool air that is the bill. To make it as efficient as possible the first step would be insulation and gap sealing. Ensure total sealing at the bottom of doors cold air is like liquid drops like a stone. Second windows double glazed if possible roof insulated and then the type wall you have. When that is taken care of your will seldom have it running and be cool with a constant temp. They have little idea when sell hi ng they just ask how big the room is and how many windows never ask about insulation. Lastly depending where you are you might consider connect solar panels and a few Lipo batteries. After a year or so it will be paid off.