Lower than 3,000 baht
The payback may be long. Daytime loads should be examined and small systems considered carefully.
Article · Evaluate suitability
Is solar PV worthwhile for your home?
No need to guess from the size of your house. Try checking from 5. Matters that actually have an effect include the amount of the electricity bill, the time period of using the electricity, the roof, sunlight, and the original electrical system.
Short answer
What are the characteristics of a house that is worth using solar PV?
A house that has reasonable electricity costs and uses electricity regularly during the daytime. There is often the most worthwhile opportunity. For example, turn on the air conditioner during the day, work at home, use a water pump, multiple refrigerators, or charge an EV during the day and have a strong roof. Receives sunlight without much shade.
The word "worth it" should consider both the investment, the savings, the life of the equipment, and the period of time you plan to use the building. It's not just looking at the electricity bill for just one month.
Check the question at 1.
Is the monthly electricity bill high enough?
There is no minimum electricity bill that is guaranteed to be worthwhile. PEA uses approximately 3,000 baht per month or more as a preliminary screening guideline. But the time of using electricity is still more important.
From 3,000 baht and up
It's worth exploring if someone is home or if appliances are turned on regularly during the day.
Electricity cost is very high
That doesn't mean you have to install a large system. You must always look at kWh and power during sunny days first.
Check the question at 2.
How much electricity do you use during the day?
Let's look at the approximate range. 08:00–17:00 n. which appliances are working? Because the power from the panel will be used during this period first.
- Someone is home or working from home on weekdays.
- Turn on the air conditioner, water pump, washing machine. or daytime office equipment
- There is a refrigerator, freezer, fish pond, or appliance that works continuously.
- Washing clothes, pumping water, or charging EV cars can be moved to the daytime.
Simple way of thinking: The more solar electricity you use as it is generated, the more grid electricity you can avoid buying.
Check item 3–4.
Is the roof strong and well exposed?
enough space
Approximately, the 5 kWp panel kit may require approximately 25–40 sq.m. depends on panel power and installation distance.
Little shadow
Trees, nearby buildings, antennas, and water tanks may block some of the panels. causing electricity production to decrease
Ready to use for a long time
If your roof is old, leaking, or close to replacement. Should be repaired before installing the panels so as not to have to dismantle the system again.
It doesn't have to be a south-facing roof only. Experts can simulate the yield from the actual roof direction and angle before designing.
Check the question at 5.
Is the original electrical system supported?
The main cabinet, wiring, grounding system, meter size and power pattern must be inspected. 1 phase or 3 phase The surveyor should be able to tell what improvements need to be made and whether they are included in the quote.
- The electrical cabinet and circuit breakers are in safe condition.
- Have a proper grounding system.
- Have an area to install the inverter that is dry, ventilated and accessible for inspection.
- The wiring route is not at risk of being damaged or exposed to water.
Summarize by yourself
Checklist 8 How many questions does your house pass?
- Electricity costs approximately 3,000 baht per month or more as a preliminary guideline.
- Use electricity for several hours during the day.
- There are appliances that can be moved to open during the day.
- There is enough free roof space.
- The roof is still strong and there are no plans to replace it anytime soon.
- Not much shadow from trees or buildings.
- Plan to continue using the building for many years to come.
- Ready for experts to inspect the original electrical system.
If you pass approx. 5–8 Your house is likely worth exploring further. But the final answer should come from at least the electricity bill. 6–12 Month Load Profile or main machine use time and surveying the actual work site
Still not sure if your house is worth it or not?
Send your electric bill and roof picture to the PTH GREEN team to help with a free initial evaluation.
Read more: Price 3, 5 and 10 kWp · How many years will you reduce your electricity bill and payback?