Solar Installation Cost Calculator
Enter your electricity bill and choose the equipment you are interested in to see how many kW you need, a rough installed price, and exactly what you would be paying for.
Tell us about your electricity use
Monthly electricity bill
Check your past bills. If they vary, add up 12 months and divide by 12.
Or tap an amount close to yours
When you use power
Based on your bill and usage, the right size is about5 kW
See price and savings ↓Choose equipment to see a price
Try the brands and equipment you are interested in — the estimated price changes with each choice. The preset values are only a starting example.
Solar system size
The starting size is based on your bill and when you use power. Adjust it to compare prices.
Roof and meter
Equipment and battery
What battery size makes sense?
There is little surplus on average, so we do not recommend a battery if value for money is the goal. If you want emergency backup, start at 5 kWh and have the essential loads checked on site.
This size is a starting point for storing surplus solar power, not a guarantee of backup time. Sizing for backup means looking at the wattage of the air-con, pumps, fridges and anything else that has to run at the same time.
Choose a battery capacity first, then a brand
Estimated installation price
System size being priced
5 kW
Expected to generate about 6,750 kWh a year
Total monthly savings
~THB 2,250
Estimated installation price before VAT
THB 141,000 – 157,000
Including 7% VAT: THB 151,000 – 168,000
Estimated payback
5.6 – 6.2 years
Price including VAT divided by the savings of ~THB 27,000 a year broken down below.
Where the savings come from
- Monthly savings from the panels directly
- ~THB 2,250
- Extra monthly savings from the battery
- No battery selected
- Total monthly savings
- ~THB 2,250
- Estimated bill still to pay
- ~THB 2,250/month
- Approximate bill reduction
- ~50%
What this price includes
Equipment prices are based on the Thai market, last checked October 1, 2026.
Prices are checked again before every real quote. These prices are a first estimate only.
JA Solar solar panels
8 panels sized for this system
HUAWEI inverter
Converts solar power for use in the building, with a monitoring app
Mounting structure and fixings
Rails and fixings for a metal sheet roof
Switchboards, cabling, protection devices and grounding
Installed to the electricity authority's standards
Installation labor
Carried out by our own installation team
Permits and engineer certification
Grid-connection application to the PEA and a licensed engineer's sign-off
2-year installation warranty and 2 years of aftercare
Included at no extra charge: a yearly system check and panel clean
Total for everything above
THB 141,000 – 157,000
Before VAT · including 7% VAT: THB 151,000 – 168,000
Saves about THB 27,000 a year (~THB 2,250/month) on your electricity bill
Possible extra costs
- Roof reinforcement, if the purlins or rafters cannot take the extra load
- Meter replacement fees charged directly by the electricity authority
- Cranes or special lifting equipment for tall or hard-to-reach buildings
- Any travel charge, which we confirm before booking
This is only a rough figure for a typical site. The real price may change with roof direction, shading, roof strength and the times you use electricity. We confirm the price after reviewing your electricity bill and surveying the site — this figure is not a quote.
Where these numbers come from
How the calculator works
Rainy days already allowed for
A 1 kW system is expected to generate about 1,350 kWh a year. We use figures for Southern Thailand with the rainy season already allowed for. Real output still depends on roof direction and shading.
Based on power you can actually use
Savings are counted only from electricity your property uses straight away. Surplus power is not counted, so the figures stay conservative.
Sized to match your usage
A system that matches your daytime usage is usually better value than one that is too big. If you want a large system, your hourly usage data should be checked first.
FAQ
Common questions before installing
Is the price shown a real price?
It is a rough price based on the equipment and installation work you select, but it is not a quote. The real price may change if the roof needs reinforcing, cables have to run a long way, or the site is hard to access.
Why is income from selling surplus power not included?
Because you have to apply to the electricity authority and be approved first, and not every home can sell power back. We leave that money out to keep the estimate conservative.
Why don't you recommend the largest system?
A system that is too large may generate more than you use in the daytime, so the extra money you pay does not fully reduce your bill. We recommend a size close to your actual usage.
Can I use this figure to decide to buy?
Not yet. The calculator cannot see your roof direction, shading, the strength of the structure or when you actually run your appliances. Your past bills should be reviewed and the site surveyed before a quote is issued.
Systems of different sizes we have installed for real customers See all projects
Read before you decide
- Monthly Bill of THB 3,000, 5,000 or 10,000 — What Size Solar System Do You Need?The best-value size is not the largest your roof can hold — it is the size that matches the electricity you use during the day.
- Thai Electricity Is THB 3.95 per Unit for Sep–Dec 2026 — How to Calculate Solar Payback CorrectlyThe tariff you see in the news and the rate you actually pay are not the same. Here's how to work out your own real cost per unit so your payback calculation is accurate.
- Solar Payback in 2–3 Years? How to Work Out a Realistic Figure for Your HomePayback depends less on system size than on how much of the power you use yourself during the day. Here is every step of the calculation, and how much the result moves when each input changes.