Three-phase power -- same rates / kwh?

[SunshineHarvey7]

I have had more than one friend say they converted to 3-phase power and their bill went down. Can anyone explain that? When I looked for PEA rates, there seems to be no mention of lower rates for 3-phase power. 

[Woof999]

I believe that a kilowatt hour is a kilowatt hour regardless of the number of phases.

 

Typically a household 3 phase supply in Thailand will still be using a single phase for a single circuit (no 3 phase motors running, or example).

 

I cannot think of any reason why a 3 phase supply would be any cheaper. In fact, outside of Thailand, a 3 phase supply would attract extra fixed charges.

 

I have a 3 phase supply at my home. The bill looks no different than it did at other homes with a single phase supply, as far as I can tell.

[SunshineHarvey7]

16 hours ago, Woof999 said:

I believe that a kilowatt hour is a kilowatt hour regardless of the number of phases.

 

Typically a household 3 phase supply in Thailand will still be using a single phase for a single circuit (no 3 phase motors running, or example).

 

I cannot think of any reason why a 3 phase supply would be any cheaper. In fact, outside of Thailand, a 3 phase supply would attract extra fixed charges.

 

I have a 3 phase supply at my home. The bill looks no different than it did at other homes with a single phase supply, as far as I can tell.

That’s what I would expect. I guess I’m going to ask if I can see the bills before and after they switched from 2-phase to 3-phase. Of course, the best comparison is with two months that had similar weather. 

[stoner]

10 minutes ago, SunshineHarvey7 said:

That’s what I would expect. I guess I’m going to ask if I can see the bills before and after they switched from 2-phase to 3-phase. Of course, the best comparison is with two months that had similar weather. 

i have just done this with the townhouse i am in. this is out first month with 3 phase. 

[Woof999]

28 minutes ago, SunshineHarvey7 said:

That’s what I would expect. I guess I’m going to ask if I can see the bills before and after they switched from 2-phase to 3-phase. Of course, the best comparison is with two months that had similar weather. 

Time of year is also really important. I use aircon all day every day and the bills are considerably higher from late March until late August than they are for the rest of the year.

 

Also remember that we had discounted electricity for a period during COVID.

[SunshineHarvey7]

On 2/10/2023 at 2:59 PM, stoner said:

i have just done this with the townhouse i am in. this is out first month with 3 phase. 

Did you switch because you heard 3-phase is cheaper? Let us know how your bills compare, keeping in mind that last month was cooler (so you might have used less power for A/C).

[stoner]

Just now, SunshineHarvey7 said:

Did you switch because you heard 3-phase is cheaper? Let us know how your bills compare, keeping in mind that last month was cooler (so you might have used less power for A/C).

we have a business. 3 ac units are on 24 hours a day so the usage should be pretty much the same. 

 

i will post details once we have them. 

[scottiejohn]

How easy is it to go from three phase supply to standard supply?

[Crossy]

5 minutes ago, scottiejohn said:

How easy is it to go from three phase supply to standard supply?

 

Provided you don't have any 3-phase appliances, you will need a "single-phase kit" for your distribution board and for PEA to replace your meter.

 

Personally, I'd stick with 3-phase if you already have it, the main failure mode we have here is loss of one phase, of course it's always the one we are on. At least with 3-phase 2/3 of your kit still works.

[h90]

On 3/24/2023 at 4:40 PM, Crossy said:

 

Provided you don't have any 3-phase appliances, you will need a "single-phase kit" for your distribution board and for PEA to replace your meter.

 

Personally, I'd stick with 3-phase if you already have it, the main failure mode we have here is loss of one phase, of course it's always the one we are on. At least with 3-phase 2/3 of your kit still works.

yes...one phase missing, or one phase having 170 Volt against 0 while the others have 240 Volt.
Our CNC lathes make DC from AC to run their motors. And it still runs on 2 phase but as soon as a pump or other regular motor is activated and internal fuse jumps.....