I'm building a three-bedroomed bungalow with a gym and workshop.  It will be fitted out comfortably.

Chatting to Google Gemini about options for electricity recently, it suggested I should consider a three-phase supply because it felt that all the air con units (about 6) plus the water heaters for the showers, might overload a single-phase supply; it felt the load could be spread around the three circuits.  It described the typical rural single-phase supply as 15A but I don't know if this correct.  I spoke to P.E.A. about it and they said it could be done.

In England my first reaction might be to ask what the monthly standing charge would be, regardless of actual consumption, but I understand that only consumption is charged here.  I expect there would be an installation charge, hopefully not to large.

Electricity isn't my specialist subject.  Is Gemini hallucinating or could there be something in this?  Thanks in advance.

p.s. in the longer term, I expect to have solar panels and batteries in a hybrid system (always good to have a plan B, and we will have a 225 sq. m south-facing flat roof over our extension/garage) but the budget probably doesn't stretch to that this year.

Usually in Thailand you tend to lose 1 phase, due to wind rain or something, so having 3 phase would keep your house powered as you only loose 1 phase.

If your system is single phase 15/45 meter, then 3 phase can handle 3 times the current.

In my 3 phase house we have the 3 aircons on seperate phases and the house loads balanced across the 3 phases.

Kitchen power and lighting is spread across more than 1 phase so you don't lose all the kitchen or all the lights with 1 or 2 phases lost.

Not really needed but we have 3 phase multipoint water heaters that give very hot water.

3 phase is a must if you have some big motors, but not really needed but it gives you more flexibility.

 

Alternately if you look on the Alternate Energy Forum you will see some people have single phase but parallel solar inverters, so squeezing a lot more than 45A  (15/45) from the solar into the house.

A trouble with installing  3 phase into a village house is not many installers know about installing 3 phase.

8 hours ago, carlyai said:

Usually in Thailand you tend to lose 1 phase, due to wind rain or something, so having 3 phase would keep your house powered as you only loose 1 phase.

If your system is single phase 15/45 meter, then 3 phase can handle 3 times the current.

In my 3 phase house we have the 3 aircons on seperate phases and the house loads balanced across the 3 phases.

Kitchen power and lighting is spread across more than 1 phase so you don't lose all the kitchen or all the lights with 1 or 2 phases lost.

Not really needed but we have 3 phase multipoint water heaters that give very hot water.

3 phase is a must if you have some big motors, but not really needed but it gives you more flexibility.

 

Alternately if you look on the Alternate Energy Forum you will see some people have single phase but parallel solar inverters, so squeezing a lot more than 45A  (15/45) from the solar into the house.

A trouble with installing  3 phase into a village house is not many installers know about installing 3 phase.

Thanks for this.

Apart from the intial installation cost, are there any other cost implications, e.g. different consumer panel, etc?  I mentioned the idea to our electrician recently and he said different components would be needed but he didn't elaborate at the time.

I don't have any big motors or anything else that might need 3-phase but the resilience sounds handy - we get power outages frequently in the rainy season, and less frequently in the dry season.

So, the greater power capacity (probably handy if I get an EV eventually) and the resilience against power outages sounds good.  Are there any downsides, assuming my electrician can install it?

 

Probably the main downside is your electrician will say he can install anything, but if you start to ask them questions they really have no idea about 3 phase.

I got someone who installed factories so he knew more than others.

For me I did what the electrician recommended and bought the 4 Square brand Consumer Unit (CU) but 8 years later and know a little more I wouldn't go with Schneider 4 square as not very flexible and expensive. A few years ago a lightning strike took out my MOVs so to replace 3 was about B6000 from memory and when I opened one up for a look was a lot of expensive sand...probably all of B500 electronics.

I'd go for the DIN rail CU as you can install 3, one for each phase...more flexible.

I've also installed a 3 phase charger for my EV but at the moment it is just working on one phase as that's all I have in the garage at the moment.

Am going down the solar route that means for me to install it in the garage I need 8 (25mm2) cables. 4 from the grid to the garage (3 phases plus neutral), in my case from the house to the garage as already have the 4 wire 3 phase to the house and 4 coming from the garage back to the house.

And then if you arrange with PEA to buy your surplus you need cables back to the grid.

 

Sorry I just saw your post.

 

I'd draw up a box diagram, then get a schematic drawing from your electrician on exactly how he's going to do it.

Also install a 3 phase monitoring system like Zigbee energy meter and gateway so you can see exactly your energy use.

I was going to do the solar myself with help from the locals, but their too busy spacing out at the moment.

 

I had a quote to install just the one phase and it was under B100000, B20000 for the installers.

I think I can do 3 phase solar for around B200000.

@carlyai, thanks for your input.

19 hours ago, IsaanT said:

@carlyai, thanks for your input.

One more thing just remembered.

I wanted to add 3 phase RCBs for the 3 phase water heaters (2 off).

I couldn't buy a 3 phase RCB for the Schneider 4 square CU, but can buy them for the DIN rail system.

The manufacturers of the water heaters say you don't need an RCB as the unit is earthed, but .... 

So if you buy the 4 square system and want a couple of 3 phase RCB breakers it's a bit difficult.

This was the case a couple of years ago.