Solar panel package suggestion.

[Ben Zioner]

6 minutes ago, kwak250 said:

I was wanting to build a car port  mainly for shade for about 4-5 cars and put the panels on top but 35 panels would be more like the car part in Tesco.

My estimate is about 11x9 meters, for 4 rows of 9 panels, I'll split over 2 slopes inclined at 10% facing full south. By now you might have guessed that my bill is about 2000 KWh a month.

[kwak250]

21 minutes ago, Ben Zioner said:

I don't know about that, but they quoted me 2.2 THB, but reluctantly yes. Some guys here boasted that they run their meters backwards, but that's illegal and PEA is in process of changing their gear.

Yes homepro have said to us if you fit Solar they will put a digital meter on your house.

Maybe I will get them to fit the old style meter first then get a local company to fit the solar at a later date

[kwak250]

3 minutes ago, Ben Zioner said:

My estimate is about 11x9 meters, for 4 rows of 9 panels, I'll split over 2 slopes inclined at 10% facing full south. By now you might have guessed that my bill is about 2000 KWh a month.

And do you have batteries or sell back to PEA?

What sort of cost was your system or did you DIY?

[Ben Zioner]

14 minutes ago, kwak250 said:

And do you have batteries or sell back to PEA?

What sort of cost was your system or did you DIY?

I am still at the planning stage. I think I'll go ahead with the structure and all 36 panels with a 20KW hybrid inverter. Batteries I might phase in progressively starting with a one to two hours backup capacity. 

 

Again prices vary tremendously between Huawei/Tesla and some other Chinese players, so I am torn between the fear of paying too much and that of buying garbage.

[UWEB]

1 hour ago, kwak250 said:

Thanks for this info

What size System would be needed for say 60 kw ?

Or how many panels/Batteries would be needed?

Sorry total novice with this just trying to work out the cost.

21kwp would that work for us?

I have 38 panels installed in three different directions East,South and West, so I never will reach the 21 kw peak. But production starts at 7.00 am till around 5.00 pm, let say 10 hours production. If I run my Air con's, Pool Pump , charge my EV with 5 kwh plus I have my 3 x 10kwh Batteries charged from 50% after night consumption to 100% I have at the end of the day appr. 85 kw produced. But off course I don't charge my Car every day.

I general the System looks a bit oversized, but if you have a cloudy day I still can run all my Equipment , charge my Car and have full Batteries in the evening for the night.

For Panels I have 550W and 580W Longi Panels, 2 x Deye 10 KW Hybrid Inverters and 3 x LV Topsun 10 kwh Batteries.

[GammaGlobulin]

1 hour ago, Ben Zioner said:

Now I am scared..

 

Someday, soon, I will solve my power-delivery problem.

Either that, or I will BLOW A GASKET, fuming...

 

 

[Davejf2017]

21 hours ago, kwak250 said:

I did see before someone mention about the meter running backwards but was told today all new meters for Solar will be digital

If you run a digital meter backwards (exporting to the grid) you will be charged for what you export.

[Crossy]

1 hour ago, Davejf2017 said:

If you run a digital meter backwards (exporting to the grid) you will be charged for what you export.

 

Let's add a "possibly" to that. There have certainly been reports of such practices but the few meters I've looked at log export separately and the units simply don't appear on the bill.

 

Anyway, attempting to do unofficial net-metering using an electronic meter is at best unwise.

 

The old whizzy-disk meters do happily go backwards, but as previously noted the practice is frowned upon by PEA/MEA and I wouldn't recommend doing it.

 

Things were different when we started doing solar and our local PEA boss-man said (after he had stated at great length "you will not spin your meter backwards") in hushed tones "don't let the meter reader see it going backwards"  

 

These days, anything DIY should avoid exporting energy to the grid**, if you have surplus generation that you want to use at night then batteries are the order of the day.

 

If you want to go official with export (and getting "paid" for the energy) then you need to go with a certified installer = $$$

 

** We have one member who has successfully got a DIY system licenced for grid export. The costs associated seem to be IMHO simply a non-starter, spend the money on battery storage.

[kwak250]

14 minutes ago, Crossy said:

 

Let's add a "possibly" to that. There have certainly been reports of such practices but the few meters I've looked at log export separately and the units simply don't appear on the bill.

 

Anyway, attempting to do unofficial net-metering using an electronic meter is at best unwise.

 

The old whizzy-disk meters do happily go backwards, but as previously noted the practice is frowned upon by PEA/MEA and I wouldn't recommend doing it.

 

Things were different when we started doing solar and our local PEA boss-man said (after he had stated at great length "you will not spin your meter backwards") in hushed tones "don't let the meter reader see it going backwards"  

 

These days, anything DIY should avoid exporting energy to the grid**, if you have surplus generation that you want to use at night then batteries are the order of the day.

 

If you want to go official with export (and getting "paid" for the energy) then you need to go with a certified installer = $$$

 

** We have one member who has successfully got a DIY system licenced for grid export. The costs associated seem to be IMHO simply a non-starter, spend the money on battery storage.

Many thanks 

I am starting to understand all the info being given.

From what I understand if I had say 30 panels and no battery for nighttime use then I might as well just have say 15 panels for now to use for air cons/pool pump.

Probably need to find a local solar installer as homepro sounds expensive

 

[Crossy]

18 minutes ago, kwak250 said:

Many thanks 

I am starting to understand all the info being given.

Fro. What I understand if I had say 30 panels and no battery for nighttime use then I might s well just had say 15 panels for now to use for air cons/pool pump.

Probably need to find a local solar installer as homepro sounds expensive

 

 

Before going to contractors, you need to decide exactly what you want to achieve:- 

• Reduce your existing bill at lowest cost but no protection from power cuts (grid-tie but with zero-export).
• Reduce your bill and have protection from power cuts (small hybrid with small battery).
• Eliminate your bill but maintain a grid connection for backup (bigger hybrid, bigger battery).
• Go totally off grid (even bigger hybrid and batteries with lots and lots of panels).

Knowing your day (9AM to 5PM) vs night (5PM to 9AM) usage is a good starting point to determining exactly what you need so you don't waste your valuable $$$.

 

Contractors always over-estimate what their system will deliver and quote what it will do on the longest, most perfect day "forgetting" that 99% of days are not perfect.

 

[kwak250]

24 minutes ago, Crossy said:

 

Before going to contractors, you need to decide exactly what you want to achieve:- 

• Reduce your existing bill at lowest cost but no protection from power cuts.
• Reduce your bill and have protection from power cuts.
• Eliminate your bill but maintain a grid connection for backup.
• Go totally off grid.

Knowing your day (9AM to 5PM) vs night (5PM to 9AM) usage is a good starting point to determining exactly what you need so you don't waste your valuable $$$.

Eliminate your bill but maintain a grid connection for backup.

This would be ideal 

Great info as always.

Our house won't be finished until around September so will be cooler than now.

I can see why I read about people adding panels or a battery especially when it's 38c most days.

December /January our bill drops right down so lots to think about.

If I base the power consumption on these hot months it might be better having a smaller system and pay extra for the hotter months through the grid.

[Crossy]

Have you applied any thought as to where you are going to put your panels?

 

I'd avoid the house roof unless space is seriously restricted and go for your car port and/or ground mounts. Easier/safer maintenance (cleaning) and the odd leak in a car port isn't a disaster.

 

We started out with 4 x 330W panels which bred whilst I wasn't looking and are now 79 panels of various flavours totalling 27kWP and covering an expanded car-port and every other viable flat space. Honestly, I never intended going this mad but I got a great deal on a stack of panels and batteries from an estate clearance (a mate's widow just wanted them out of the way) and well, here we are

 

Car port thread here: -

 

[kwak250]

26 minutes ago, Crossy said:

Have you applied any thought as to where you are going to put your panels?

 

I'd avoid the house roof unless space is seriously restricted and go for your car port and/or ground mounts. Easier/safer maintenance (cleaning) and the odd leak in a car port isn't a disaster.

 

We started out with 4 x 330W panels which bred whilst I wasn't looking and are now 79 panels of various flavours totalling 27kWP and covering an expanded car-port and every other viable flat space. Honestly, I never intended going this mad but I got a great deal on a stack of panels and batteries from an estate clearance (a mate's widow just wanted them out of the way) and well, here we are

 

Car port thread here: -

 

I am not wanting these on the house roof 

I was planning to get a car port built and originally for around 3 cars but might make it twice the size now to accommodate extra panels.

Like you say they are easier to clean and also don't like the look of them all over the house roof

Plenty of space but 79 panels wow..

I will look at the link I did see it before when I was not ready to get into solar systems but thanks for that .

[Crossy]

Car ports with solar panels make excellent (and cool) entertainment spaces 🙂

 

Stick some LED strip lights in there and you can host local wedding parties etc.

 

The underside of our car-port roof before we finished installing the panels, guess where the solar panels end ...

 

 

 

 

[kwak250]

41 minutes ago, Crossy said:

Have you applied any thought as to where you are going to put your panels?

 

I'd avoid the house roof unless space is seriously restricted and go for your car port and/or ground mounts. Easier/safer maintenance (cleaning) and the odd leak in a car port isn't a disaster.

 

We started out with 4 x 330W panels which bred whilst I wasn't looking and are now 79 panels of various flavours totalling 27kWP and covering an expanded car-port and every other viable flat space. Honestly, I never intended going this mad but I got a great deal on a stack of panels and batteries from an estate clearance (a mate's widow just wanted them out of the way) and well, here we are

 

Car port thread here: -

 

My wife just asked if y.ou supply the whole village hahaha

She thought I was crazy when I said I might need about 20 panels.

[Crossy]

Rule one of solar - We don't talk about solar.

 

Ah sorry, wrong rule!

• Rule one of solar - You can never have too much solar!
• Rule two of solar - You can never have too much storage!
• Rule three of solar - If you are breaking rules 1 and/or 2, buy an EV. 

 

Once you've been bitten by the free-energy bug you will be assimilated!

Resistance is futile!

[brfsa2]

I got a 5kW setup and paid roughly 210,000 baht. Without power optimizer, it would be 25K baht cheaper.

- Huawei 5kW inverter (it's the best you can get in Thailand, and the Fusion solar app is pretty good)

- 9 x 555watt Monocrystalline panels highest grade

- 9 x power optimizer (this is optional)

 

Batteries are super expensive here, unless you got with an inverter that supports any battery, such as Lead acid or LifePo4 batteries.

The downside of the Huawei inverter is that it only works with the Huawei LUNA batteries. It's 145,000 baht for the 7kWh LUNA battery.

 

My electricity bill went down from 15,000 baht to less than 5,000 baht now. (I have EV cars)

I sell back the excess to MEA at 2.20 Baht per kWh.

[brfsa2]

21 hours ago, Crossy said:

Car ports with solar panels make excellent (and cool) entertainment spaces 🙂

 

Stick some LED strip lights in there and you can host local wedding parties etc.

 

The underside of our car-port roof before we finished installing the panels, guess where the solar panels end ...

 

 

 

 

 

That's another reason I went for Solar on my Roof side that bothers me the most with the heat.

It's so much cooler now that side of the house.

[pdinbkk]

On 4/8/2025 at 8:36 PM, Middle Aged Grouch said:

They say Kunini Solar is the most reputable in Thailand ? Any comments or suggestions ? Thanks.

I have used them extensively.  They are excellent.

[kwak250]

1 hour ago, brfsa2 said:

I got a 5kW setup and paid roughly 210,000 baht. Without power optimizer, it would be 25K baht cheaper.

- Huawei 5kW inverter (it's the best you can get in Thailand, and the Fusion solar app is pretty good)

- 9 x 555watt Monocrystalline panels highest grade

- 9 x power optimizer (this is optional)

 

Batteries are super expensive here, unless you got with an inverter that supports any battery, such as Lead acid or LifePo4 batteries.

The downside of the Huawei inverter is that it only works with the Huawei LUNA batteries. It's 145,000 baht for the 7kWh LUNA battery.

 

My electricity bill went down from 15,000 baht to less than 5,000 baht now. (I have EV cars)

I sell back the excess to MEA at 2.20 Baht per kWh.

Sounds good.
Did you do the install?
Also how long did it take to manage to sell back excess as thought it takes a long time to set up with checks 

[1FinickyOne]

On 4/8/2025 at 3:33 PM, BritManToo said:

Around 105kbht all in and a bit of sweat!

And how much electric [in baht] will that give me per month? Is it finally at a point where it is worth it? 

[BritManToo]

16 minutes ago, 1FinickyOne said:

And how much electric [in baht] will that give me per month? Is it finally at a point where it is worth it? 

36 units a day = 150bht x 30 = 4,500-5,000bht a month

[Pink7]

I used to have 3-4k in electric bill per month  (upto 1000 units per month)

 

My setup is 2 x 5k Inverters, 2 x 280 amp battery packs, 28 panels x330 watt. Total 300K 2 years ago ( DIY with some hired help). Its cover 99% of our power needs.

 

BA

[BritManToo]

58 minutes ago, Pink7 said:

I used to have 3-4k in electric bill per month  (upto 1000 units per month)

 

My setup is 2 x 5k Inverters, 2 x 280 amp battery packs, 28 panels x330 watt. Total 300K 2 years ago ( DIY with some hired help). Its cover 99% of our power needs.

 

BA

Panel prices have dropped a lot since then, your panels would have cost around 3kbht each, now you can buy panels double that capacity for 2kbht each.

Your 28 units a day cost you 90kbht, now you can get the same number of units a day for 28kbht.

[Pink7]

1 hour ago, BritManToo said:

Panel prices have dropped a lot since then, your panels would have cost around 3kbht each, now you can buy panels double that capacity for 2kbht each.

Your 28 units a day cost you 90kbht, now you can get the same number of units a day for 28kbht.

Yes i noticed that. Its great so many more can go solar. I see batteries going down too.

 

BA

[brfsa2]

18 hours ago, kwak250 said:

Sounds good.
Did you do the install?
Also how long did it take to manage to sell back excess as thought it takes a long time to set up with checks 

no way I'd do it myself. even thou I have the full knowledge of it.

I could definitely do it on a smaller scale if not on a modern house roof with 2 guys helping me.

 

- If you are planing to do on-grid solar setup for your house, and looking to sell back to the grid, then get a reputable Vendor to do it.

- If you know electric, you want something small and off-grid and you have a few electricians to help you, then yeah you can do it.

unless you are expert like the other guys posting in this forum, just hire.

 

my house setup was 6 guys working on it, took almost whole day.

they started with

1. Roof rails, drill holes in the roof, attach rails

2. Attach panels

3. Wiring, and conduits

4. Dedicated Grounding rod (I now have 3 ground rods in my house, the more the better: built-in the House, EV chargers, Solar)

5. panels, inverter, meter.

 

and of course, they left many holes not fully closed in roof, normal in Thailand that 99% of engineers cannot finish the job, always leave something undone or half done

[BritManToo]

4 minutes ago, brfsa2 said:

no way I'd do it myself. even thou I have the full knowledge of it.

I could definitely do it on a smaller scale if not on a modern house roof with 2 guys helping me.

 

- If you are planing to do on-grid solar setup for your house, and looking to sell back to the grid, then get a reputable Vendor to do it.

- If you know electric, you want something small and off-grid and you have a few electricians to help you, then yeah you can do it.

unless you are expert like the other guys posting in this forum, just hire.

 

my house setup was 6 guys working on it, took almost whole day.

they started with

1. Roof rails, drill holes in the roof, attach rails

2. Attach panels

3. Wiring, and conduits

4. Dedicated Grounding rod (I now have 3 ground rods in my house, the more the better: built-in the House, EV chargers, Solar)

5. panels, inverter, meter.

 

and of course, they left many holes not fully closed in roof, normal in Thailand that 99% of engineers cannot finish the job, always leave something undone or half done

No need to put the panels on your roof.

Mine are on top of my garden wall.

[brfsa2]

8 minutes ago, BritManToo said:

No need to put the panels on your roof.

Mine are on top of my garden wall.

 

Nice! you can even wash it yourself. 

unfortunately my setup in Bangkok house has to be in the roof. It also helped a lot getting house 2nd floor cooler.

 

Now, on my new house in the country side I will also do it in the roof but it will be a flat concrete roof, so I can wash it myself.

still 2 years before the house is built.

 

I am also considering potentially doing it on the Garage roof, I will have a detached garage and storage room on the side.

Actually after I writing it, that makes even more sense now to put on garage. Let's see...

 

 

 

 

[Pink7]

23 hours ago, BritManToo said:

Panel prices have dropped a lot since then, your panels would have cost around 3kbht each, now you can buy panels double that capacity for 2kbht each.

Your 28 units a day cost you 90kbht, now you can get the same number of units a day for 28kbht.

Do you have link to the panel deal you found?

 

Pink

[BritManToo]

1 hour ago, Pink7 said:

Do you have link to the panel deal you found?

 

Pink

https://s.lazada.co.th/s.EY5iY

I paid 1,976bht Inc delivery in the 4/4 sale, same price on sale day every month.

And they work earlier and later than our 340w panels.

 

Today they're 2,092 delivered as not a sale day.