Net Billing in Thailand: How It Works in 2026
🔑 Key Takeaways
- Net billing lets you sell excess solar electricity to PEA at ~฿2.70/kWh
- It's not the same as net metering — you buy at ฿5+ but sell at ฿2.70
- Application takes 2–4 weeks through PEA
- Available for systems up to 10 MW (residential and commercial)
- Maximizing self-consumption is more profitable than exporting
If you're considering solar panels in Thailand, you've probably heard about "net billing" or "net metering." These terms are often confused, and the difference matters — it directly affects how much money you make (or save) from your solar system.
This guide explains exactly how Thailand's net billing program works in 2026, how to apply, and how to maximize its benefits.
1. What Is Net Billing?
Net billing is Thailand's program that allows solar panel owners to sell excess electricity back to the grid. When your solar panels produce more electricity than you're using at any moment, the excess flows to the PEA (Provincial Electricity Authority) grid, and you receive a credit on your electricity bill.
The Simple Version
- Your solar panels generate electricity during the day
- You use as much as you need in real-time (free)
- Any excess automatically flows to the PEA grid
- PEA measures the export with a bi-directional meter
- You receive a bill credit at the wholesale rate (~฿2.70/kWh)
- Credits offset your next electricity bill
2. Net Billing vs Net Metering — The Critical Difference
This is where most people get confused. Thailand uses net billing, not net metering. The difference is significant:
Net Billing (Thailand's System)
- Export rate: ~฿2.70/kWh
- Import rate: ~฿5.00–6.00/kWh
- You buy high, sell low
- Credits are monetary (฿)
- Favors self-consumption
Net Metering (Not Used in Thailand)
- Export rate: Same as import
- 1 kWh exported = 1 kWh credited
- True 1:1 exchange
- Credits are kWh-based
- Much more favorable for solar owners
⚠️ Important Implication
Because Thailand uses net billing (not net metering), every kWh you consume yourself is worth nearly double the value of a kWh exported. This means system design and usage patterns matter enormously. Don't oversize your system — match it to your daytime consumption.
3. How Net Billing Works — Step by Step
During the Day (Solar Producing)
- Scenario A — You use 3 kW, panels produce 5 kW: 3 kW powers your home (free), 2 kW exports to grid (earns ฿2.70/kWh credit)
- Scenario B — You use 6 kW, panels produce 5 kW: 5 kW from solar (free), 1 kW from grid (you pay PEA rate)
- Scenario C — You use 0 kW (nobody home), panels produce 5 kW: All 5 kW exports to grid (earns ฿2.70/kWh credit)
At Night (No Solar)
- All electricity comes from PEA grid at normal rates
- Your daytime export credits offset this nighttime consumption
- Credits carry forward month-to-month within the billing cycle
Monthly Bill Calculation
| Line Item | Example |
|---|---|
| Electricity imported from grid | 800 kWh × ฿5.20 = ฿4,160 |
| Electricity exported to grid | 400 kWh × ฿2.70 = –฿1,080 |
| Service charge + VAT | +฿150 |
| Total Bill | ฿3,230 (down from ฿6,300 without solar) |
4. Current Net Billing Rates (2026)
| Category | Export Rate | Contract Duration |
|---|---|---|
| Residential (≤10 kW) | ~฿2.70/kWh | 10 years |
| Commercial (10–1,000 kW) | ~฿2.70/kWh | 10 years |
| Industrial (1–10 MW) | ~฿2.60/kWh | Negotiated |
Note: Rates are set by the Energy Regulatory Commission (ERC) and may be adjusted. The wholesale avoided-cost rate has been approximately ฿2.60–2.80/kWh since the program's inception.
5. How to Apply for Net Billing
Install Your Solar System
System must be installed by a licensed electrician and meet PEA safety standards. Your installer (like Bustan Energy) handles technical compliance.
Prepare Documentation
Required: house registration (ทะเบียนบ้าน), ID card, PEA account details, single-line diagram (SLD), system specifications, installer license copy.
Submit Application to PEA
Applications can be submitted at your local PEA office or online through PEA's portal. Bustan Energy submits this on your behalf.
PEA Inspection
PEA sends an inspector to verify the installation meets safety standards, including proper grounding, protection devices, and anti-islanding.
Bi-Directional Meter Installation
PEA installs a new meter that measures both import and export. This replaces your existing meter at no additional cost.
Contract Signing & Activation
Sign the net billing agreement with PEA. Your system is now officially connected and earning credits. Timeline: typically 2–4 weeks from application to activation.
6. Tips to Maximize Net Billing Earnings
Strategy 1: Optimize Self-Consumption First
Since self-consumption saves ฿5–6/kWh while export earns only ฿2.70, prioritize using your own solar electricity:
- Run heavy appliances (AC, pool pump, water heater) during 10am–3pm
- Use smart timers for washing machines, dryers, dishwashers
- Charge EVs during peak solar hours
- Consider a battery system for evening use
Strategy 2: Right-Size Your System
Don't install the biggest system possible. Instead, match your system size to your daytime consumption. A well-matched system achieves 70–80% self-consumption, maximizing overall value.
Strategy 3: Monitor and Adjust
Use your inverter's monitoring app to track production vs consumption patterns. Adjust your habits based on data — even small changes can shift your self-consumption ratio by 10–15%.
Strategy 4: Consider Time-of-Use (TOU) Rates
If your PEA account is on TOU billing, solar is even more valuable during peak hours (9am–10pm weekdays) when rates are highest. Solar production aligns perfectly with these expensive hours.
🇹🇭 สรุปภาษาไทย — ระบบ Net Billing คืออะไร?
ระบบ Net Billing ของประเทศไทย ช่วยให้ผู้ติดตั้งโซลาร์เซลล์สามารถขายไฟฟ้าส่วนเกินกลับเข้าระบบ กฟภ. ได้ในราคาประมาณ 2.70 บาทต่อหน่วย
ข้อควรทราบ: ระบบนี้ไม่ใช่ Net Metering (ซึ่งจะได้ราคาเท่ากันทั้งซื้อและขาย) แต่เป็นระบบที่คุณซื้อไฟในราคาสูง (~5 บาท) และขายกลับในราคาต่ำ (~2.70 บาท) ดังนั้น การใช้ไฟฟ้าจากโซลาร์โดยตรงจะคุ้มค่ากว่าการขายกลับ
ขั้นตอนการสมัคร:
- ติดตั้งระบบโซลาร์เซลล์
- เตรียมเอกสาร (ทะเบียนบ้าน, บัตรประชาชน, รายละเอียดบัญชี กฟภ.)
- ยื่นใบสมัครที่ กฟภ.
- รอตรวจสอบจาก กฟภ.
- ติดตั้งมิเตอร์สองทาง
- เซ็นสัญญาและเปิดใช้งาน (ใช้เวลาประมาณ 2–4 สัปดาห์)
Bustan Energy ดำเนินการเรื่องเอกสารและการสมัครทั้งหมดให้คุณ!
Frequently Asked Questions
Can I earn more than I consume? Will PEA pay me cash?
Credits can offset your bill to near zero, but PEA does not issue cash payments for excess credits in most residential agreements. Excess credits typically roll over to the next billing period. This is another reason not to massively oversize your system.
Do I need a special meter?
Yes. PEA installs a bi-directional (import/export) meter as part of the net billing activation. This is provided by PEA at no extra cost to you.
Can foreigners apply for net billing?
The PEA account must be in a Thai entity's name. If you own property through a Thai company (common for foreign owners), the company can apply. The signatory must be an authorized director.
Is there a maximum system size?
For residential net billing, systems up to 10 kW are standard. Commercial systems up to 1 MW (and beyond with special agreements) are eligible. Your system size cannot exceed your PEA contracted capacity.
What happens if the policy changes?
Your net billing contract locks in the rate for the contract period (typically 10 years). Policy changes would apply to new applications, not existing contracts.
Does Bustan Energy handle the application?
Yes — we handle the entire process from documentation to PEA inspection to meter installation. It's included in our installation package at no extra charge.
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