I'm thinking of having solar panels fitted onto the roof of my small house build, how many panels for a smallish build like a 1 bedroom, lounge Bathroom/shower outside kitchen ( some power points ) cost ? installation details. thanks Barramarra.

Got me beat why anyone would want solar heating in Thailand. It does get a bit cool around Christmas in the north , granted.

17 minutes ago, emptypockets said:

Got me beat why anyone would want solar heating in Thailand. It does get a bit cool around Christmas in the north , granted.

Hot water for cleaning?

I don't know anything about solar heating i thought it was a power source for powering the home.

2 hours ago, emptypockets said:

Got me beat why anyone would want solar heating in Thailand. It does get a bit cool around Christmas in the north , granted.

For coffee

3 hours ago, BarraMarra said:

how many panels for a smallish build like a 1 bedroom, lounge Bathroom/shower outside kitchen ( some power points ) cost ?

One A/C running at a time .

Five 600w panels .

3Kw inverter .

All the railings, breakers etc installed and signed off by a certified electrician, less than 100,000 THB .

Adding a battery ? Double the price .

Yeah, not a million miles off.

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And it's worth noting: -

On 6/14/2026 at 10:29 PM, Packer said:

One A/C running at a time .

Five 600w panels .

3Kw inverter .

All the railings, breakers etc installed and signed off by a certified electrician, less than 100,000 THB .

Adding a battery ? Double the price .

At Bht 4 per unit, how long would the a/c need to be used to warrant Bht 100,000 investment?

Size the system by your current MEA/PEA bill, usage. Usage history will be on the bottom of the bill. 5 kW system should be a nice supplement for those no using much electric.

We have an 8kW system, and handles 1000+kWh a month with no problem. Are you home during the day ?

Our usage overnight is minimal, 14 hrs of no real production, and we only use 6-8kWh, and that's with 1 AC running all night. 55" TV would be the other heavy use appliance, but only 100w / hr.

If you want hot water for cleaning buy a black water storage tank and put it in a sunny area. By 10 am it should be plenty hot.

On 6/14/2026 at 6:24 PM, BarraMarra said:

I'm thinking of having solar panels fitted onto the roof of my small house build, how many panels for a smallish build like a 1 bedroom, lounge Bathroom/shower outside kitchen ( some power points ) cost ? installation details. thanks Barramarra.

Depends on your location as factoring Solar requires location, orientation, shading, estimated usage and load requirements and maybe calculations if trying to cool an older house with no ceiling insulation and poorly insulated windows, doors.

Quick method is like someone mentioned take your power and look at peak months usage. If your going to be staying long term than calculate a system that harvests 25% to 35% more energy for runs of cloudy rainy days.

Understand it is an investment. At 4 baht per KWH it will take you a long time to break even

On 6/14/2026 at 10:29 PM, Packer said:

One A/C running at a time .

Five 600w panels .

3Kw inverter .

All the railings, breakers etc installed and signed off by a certified electrician, less than 100,000 THB .

Adding a battery ? Double the price .

Or 20,000bht if you do it yourself.

Setting the break even point at around 18 months.

Edited Tuesday at 01:28 AM2 days by BritManToo

40 minutes ago, KhunLA said:

Our usage overnight is minimal, 14 hrs of no real production, and we only use 6-8kWh, and that's with 1 AC running all night. 55" TV would be the other heavy use appliance, but only 100w / hr.

No refrigerator at your house?

On 6/14/2026 at 6:24 PM, BarraMarra said:

I'm thinking of having solar panels fitted onto the roof of my small house build, how many panels for a smallish build like a 1 bedroom, lounge Bathroom/shower outside kitchen ( some power points ) cost ? installation details. thanks Barramarra.

I installed a 5kw inverter. 10 solar panels and 10kw batter.

Cost me just under 200k.

Saves me about 3000 baht a month.

Key is to know your energy usage. If you use 70% of your energy during the day. You need a battery, which is the expensive part. The overall usage determines what capacity you should have. If your bill isnt over 1000 i wouldnt bother, if over 2000 then you will get some value.

From your description it sounds like you a low user of electricity. Fyi. Most ACs use about 1 to 1.5kw per hour (read AC specs) . Thats the biggest user. Pool pump (if have) about 1kw. Lights tv refrig cooking and fans.. Thats less than 500 to 800 baht a month usually, so not much

1 hour ago, BritManToo said:

Or 20,000bht if you do it yourself.

3000w of panels, all railings, wires, breakers, grounding, + 3Kw inverter for 20,000, post the link.

14 minutes ago, Packer said:

3000w of panels, all railings, wires, breakers, grounding, + 3Kw inverter for 20,000, post the link.

I was thinking 6k2 inverter and 5x 580w panels for 20kbht.

Inverter PowMr 6k2 ...... 7kbht on Lazada (sale days)

5x 580w Split mono bifacial @ 2k5bht each ......... 12k5bht (sale days).

(my panels were 1k7 inc delivery, but price has gone up this month)

And a few lengths of 4x3 box steel to make the mount frames.

No need for battery as the PowMr can export to grid in SUB mode (I turn it off on meter reading day).

We have three houses, but I would only be looking to install solar power on the main house, as the other two have very minimal electricity usage.

The main house is a reasonably large bungalow. We have a fridge-freezer, a separate freestanding freezer outside, electric gates, two large televisions, and air conditioning in one bedroom, a washing machine, and the usual scattering of fans around the house.

Our average monthly electricity bill for the main house is typically between 2,500 and 4,000 baht. TBF, it usually hangs around 3200 baht to 3500 baht.

Given this level of consumption, would a solar installation be a worthwhile investment?

Moreover, are solar installation standards and after-sales support now well established in Isaan?

Our local PEA has been advertising systems starting at around 240,000 baht, and I would be interested to know whether this represents good value and what sort of payback period I could realistically expect.

I am not knowledgeable in this particular area of solar power supplies in Thailand, plus every man and his dog seems to be touting solar these days around here.

Edited Tuesday at 04:23 AM2 days by Scouse123

37 minutes ago, BritManToo said:

No need for battery as the PowMr can export to grid in SUB mode (I turn it off on meter reading day).

For On-Grid (Grid-Tied) Systems: If you connect your panels to the utility grid, you must follow regulations. Installing a grid-tied system without official approval is strictly prohibited because it can backfeed electricity, endangering utility workers.

On 6/14/2026 at 6:24 PM, BarraMarra said:

I'm thinking of having solar panels fitted onto the roof of my small house build, how many panels for a smallish build like a 1 bedroom, lounge Bathroom/shower outside kitchen ( some power points ) cost ? installation details. thanks Barramarra.

Had a hybrid solar system fitted mid April. 8×600W solar panels, 6kWh hybrid inverter, 10kWh battery, legally registered with the PEA, 150,000 baht. House is two bedroom with 12,000 and 9,000 btu AC units. I have an electric oven, electric showers and an electric well pump used for watering the garden. The last month was the first billing period for a full month of solar and the bill was 37 baht for 3 units. The way the inverter works uses about 0.1kWh of grid power per day. Max daily output I have achieved so far is 22kWh.

13 minutes ago, Packer said:

For On-Grid (Grid-Tied) Systems: If you connect your panels to the utility grid, you must follow regulations. Installing a grid-tied system without official approval is strictly prohibited because it can backfeed electricity, endangering utility workers.

Complete BS.

ALL inverters that can export to grid have anti islanding.

On 6/14/2026 at 1:39 PM, emptypockets said:

Got me beat why anyone would want solar heating in Thailand. It does get a bit cool around Christmas in the north , granted.

For example for hot water...😉 I use that, works perfectly, and sames me electricity in a four bed house...👍

Thanks for the Advice Fellas, think i will give the solar stuff a miss sounds very expensive and at my age don't think it would be beneficial years down the line fo any saving. Just have to remind the girlfriend to switch lights off when not needed.

1 hour ago, BritManToo said:

Complete BS.

"Thailand: Installing a grid-tied system without official approval is strictly prohibited"

You are completely correct; installing an unapproved on-grid (grid-tied) solar system is strictly prohibited under the Electricity Act, and doing so can void insurance and result in legal penalties. [1]

26 minutes ago, Packer said:

"Thailand: Installing a grid-tied system without official approval is strictly prohibited"

You are completely correct; installing an unapproved on-grid (grid-tied) solar system is strictly prohibited under the Electricity Act, and doing so can void insurance and result in legal penalties. [1]

It's a bit like not wearing a helmet when driving a m/c is strictly prohibited ...........

As for insurance, I don't have any for anyone to void.

is a solar system worth it? personally, i would look at it this way:

if your electricity bill is below 2,000 thb per month, it is usually not worth it, unless you plan to do it yourself and enjoy solar projects as a hobby!

from around 3,000 thb per month onwards, it can make sense. however, you should consider the following points when planning the system size:

• how many units of electricity do you use between 7:00 am and 5:00 pm while the solar system is producing power?

• how much electricity do you use during the remaining hours of the day without solar production?

this helps you decide whether an expensive hybrid solar system with battery storage (at what size) is worth installing ...

other factors to consider:

• is it a DIY project or will it be installed by a solar company? (professional installation can easily double the cost)

• does your house have a single-phase or three-phase connection? (this affects the installation cost)

• do you want to sell surplus electricity back to pea? this involves a lot of paperwork (and additional cost), and it can be even more difficult to obtain approval for a DIY installation.

but you can also start with a small plug-in solar project using a microinverter. this can be a simple and relatively low-cost way to gain experience with solar power and reduce some of your daytime electricity consumption ...

in the end, it is simply a numbers game. how much are you willing to invest, and does the effort and expected ROI make sense for you?

... have fun with your solar project!

1 hour ago, khunPer said:

For example for hot water...😉 I use that, works perfectly, and sames me electricity in a four bed house...👍

I also have solar to generate power. I didn't install it for the purpose of boiling a kettle to make a cup of tea.

I use an electric jug or gas kettle for that.

11 minutes ago, motdaeng said:

how many units of electricity do you use between 7:00 am and 5:00 pm while the solar system is producing power?

Good luck generating anywhere near rated output during those hours.

I've monitored my system and the hours when it approaches anywhere near rated power is between 10am and 3 pm.

1 hour ago, Packer said:

"Thailand: Installing a grid-tied system without official approval is strictly prohibited"

You are completely correct; installing an unapproved on-grid (grid-tied) solar system is strictly prohibited under the Electricity Act, and doing so can void insurance and result in legal penalties. [1]

And kill electrical workers. The system should shut down when the electrical supply from the authority is interrupted.

There may be systems where they will disconnect automatically from the supply and run in the local environment only.

15 minutes ago, emptypockets said:

And kill electrical workers.

He is both committing and promoting criminal acts that are not only are illegal, but could easily be deadly.

14 minutes ago, emptypockets said:

Good luck generating anywhere near rated output during those hours.

I've monitored my system and the hours when it approaches anywhere near rated power is between 10am and 3 pm.

the production is of course not linear throughout the day. solar output depends on the sun's position, weather conditions, temperature, panel angel, and shading.

you are right, most of the energy is typically generated around midday, while production is much lower in the early morning and late afternoon ...

32 minutes ago, motdaeng said:

is a solar system worth it? personally, i would look at it this way:

if your electricity bill is below 2,000 thb per month, it is usually not worth it, unless you plan to do it yourself and enjoy solar projects as a hobby!

from around 3,000 thb per month onwards, it can make sense. however, you should consider the following points when planning the system size:

• how many units of electricity do you use between 7:00 am and 5:00 pm while the solar system is producing power?

• how much electricity do you use during the remaining hours of the day without solar production?

this helps you decide whether an expensive hybrid solar system with battery storage (at what size) is worth installing ...

other factors to consider:

• is it a DIY project or will it be installed by a solar company? (professional installation can easily double the cost)

• does your house have a single-phase or three-phase connection? (this affects the installation cost)

• do you want to sell surplus electricity back to pea? this involves a lot of paperwork (and additional cost), and it can be even more difficult to obtain approval for a DIY installation.

but you can also start with a small plug-in solar project using a microinverter. this can be a simple and relatively low-cost way to gain experience with solar power and reduce some of your daytime electricity consumption ...

in the end, it is simply a numbers game. how much are you willing to invest, and does the effort and expected ROI make sense for you?

... have fun with your solar project!

The best question is: how much electricity do you want to use to live comfortably during the hot season? You cannot measure comfort and future safety only against money.

Get a proper company to do the work for you, and double the panels and battery capacity you calculate you need. But if you use less than 2,000 baht a month, I would not bother if the grid is reliable where you live.

Here, the grid is not only unreliable, it is unstable. It shuts on and off 10–12 times a week, especially during the rain season. The voltage drops below 170V and has dipped down to 153V during peak stress.

At that point, solar and batteries are not only about saving money. They are about protecting equipment, keeping the house running