If you’re a factory owner in Thailand considering solar, the first question is always: “How much will I save?” Let’s break it down with real numbers.
The Short Answer
A 500kW rooftop solar system in Thailand typically saves a factory THB 2-3 million per year in electricity costs, with a payback period of 3-5 years for self-investment — or immediate savings under our EMC model with zero upfront cost.
The Detailed Calculation
| System Size | 500 kWp |
| Panel Count | ~926 panels (540W each) |
| Rooftop Area Required | ~3,500 sqm |
| Annual Generation | ~700,000 kWh |
| Self-Consumption Rate | ~80% |
Savings Under Different Models
Self-Build (EPC Turnkey)
- System Cost: ~THB 15-18 million (THB 30-36/W)
- Annual Savings: THB 2.2-2.8 million
- Payback: 3.8-5.0 years
- 25-Year Total Savings: THB 55-70 million
EMC Contract Energy Management
- Upfront Cost: THB 0
- Electricity Discount: 10-20% below grid rate
- Annual Savings: THB 350,000-700,000
- 20-Year Total Savings: THB 7-14 million
- No maintenance responsibility
Rooftop Lease Model
- Turn your idle rooftop into steady rental income
- No investment or operational responsibility
- Coming to Thailand soon
Factors That Affect Your Savings
- Electricity Rate — TOU tariff users save more
- Roof Orientation — South-facing generates 5-10% more
- Shading — Nearby buildings reduce output
- Consumption Pattern — Daytime-heavy usage maximizes self-consumption
- Tax Incentives — Up to THB 200,000 deduction
Storage Option: Enhancing Your Solar ROI
Adding battery storage can further improve economics: increased self-consumption to 90%+, peak shaving savings THB 200,000-500,000/year, backup power for critical operations.
