Performance is also key for Thais turning to this renewable energy
PUBLISHED : 29 Dec 2025 at 01:01
NEWSPAPER SECTION: Business
WRITER: Yuthana Praiwan and Kanana Katharangsiporn
As electricity prices remain volatile and climate concerns intensify, rooftop solar panels have become an increasingly attractive option for Thai households.
By 2026, the market is expected to be more mature, competitive and technologically advanced. Yet for homeowners, the decision is no longer just about price or panel size. Safety and performance have emerged as the defining factors that separate a reliable long-term system from a costly mistake.
According to Techatat Buranaaudsawakul, chairman of the Electrical Engineering Department at the Engineering Institute of Thailand (EIT), rooftop solar should be treated as part of a home’s critical electrical infrastructure, not simply an add-on appliance.
“Safety is a top priority for rooftop solar,” Mr Techatat told the Bangkok Post. “A solar energy system must be designed and installed to the same safety standards as any other electrical system in the house. If homeowners focus only on cost savings without understanding safety requirements and system efficiency, they may expose their families and properties to unnecessary risks.”
In 2026, a typical residential rooftop solar system in Thailand is expected to cost between 150,000 and 400,000 baht, depending on capacity, inverter technology, and whether a battery system is included. Falling equipment prices have made solar more accessible, but experts caution against choosing systems based solely on the lowest quote.
Hidden costs may arise if equipment does not comply with national standards or if essential safety features are omitted. These risks can translate into higher insurance premiums, inspection failures or unexpected downtime, eroding financial benefits.
For most households, rooftop solar offers a payback period of 4-5 years, depending on electricity consumption and system efficiency. Homes with higher daytime usage, such as work-from-home households or families with electric vehicles, tend to see faster returns.
Performance consistency is critical. Poorly designed or unsafe systems may suffer frequent shutdowns, energy losses or faster degradation, reducing long-term savings. High-efficiency inverters, intelligent energy management systems and certified batteries are crucial for predictable returns over a lifespan that can exceed 20 years.
Mr Techatat says safety is a top priority for rooftop solar.
Homeowners must apply for grid connection approval from the Provincial Electricity Authority or the Metropolitan Electricity Authority (MEA). Installations must comply with Thailand’s electrical standards and be certified by qualified engineers.
Documentation typically includes system design drawings, equipment specifications and safety compliance reports. Systems aligned with the latest EIT standards tend to pass inspections more smoothly, while also protecting homeowners legally and financially.
Thailand’s latest benchmark is the “EIT 2025 – Thai Electrical Code: Solar Power Supply and Battery Energy Storage Systems 2025”. The code emphasises fire prevention, arc fault protection, and rapid shutdown mechanisms.
One of the most critical requirements is the Arc Fault Circuit Interrupter (AFCI) for inverters. Under EIT standards, inverters must be equipped with DC AFCI capable of cutting off power within 2.5 seconds when an arc fault is detected, in accordance with IEC 63027 or UL 1699B.
“AFCI is essential for preventing fires caused by direct current electrical arcs, which are often invisible but extremely dangerous,” Mr Techatat explained.
Rapid shutdown functionality is also mandatory. This feature enables the system to quickly reduce voltage during emergencies, protecting firefighters, technicians and occupants.
Huawei’s inverter and optimiser meet these standards, with the inverter equipped with a built-in and AFCI-certified feature that cuts off DC arcs within 0.5 seconds. The optimiser features rapid shutdown that reduces voltage to less than 30 Vdc during a fire. Advanced solutions such as Huawei FusionSolar integrate high-efficiency inverters, intelligent monitoring, and safety-by-design architecture.
Compatibility between rapid shutdown systems, power line communication and other protective mechanisms such as earth fault detection is also critical.
“All components must work together seamlessly,” Mr Techatat said.
“If communication protocols are not properly designed, safety systems may fail to activate when needed.”
He also clarified a common misconception.
“Many people misunderstand that EIT standards require AFCI and RSD only for rooftop solar systems larger than 200 kW. This is wrong and leads to risks. All rooftop solar, regardless of capacity, must be equipped with AFCI and RSD safety functions,” said Mr Techatat.
For battery energy storage systems, safety certification is even more important. Batteries store large amounts of energy and must be designed to prevent hazards. Homeowners should look for waterproof and dustproof protection (IP66), high-quality cells, safeguards against electrical risks, and emergency pressure release systems to reduce ignition and fire spread.
Batteries should comply with internationally recognised standards such as IEC 62619, IEC 63056, UN38.3, VDE 2510-50, CE, RCM, ISO 13849, REACH and RoHS, covering thermal stability, electrical safety, transport safety, and environmental compliance.
Homeowners are warned against purchasing rooftop solar systems from small or inexperienced contractors whose installations may not meet required standards, said Poramate Pichitanont, manager for renewable energy at MEA Smart Energy Solution.
Many solar-equipped homes remain connected to the state grid, as households still rely on electricity at night. This requires inspection by electricity authorities to ensure that solar-generated power does not flow back into the grid improperly.
“Solar power cannot be used if the installation fails inspection,” Mr Poramate said.
He advised homeowners to look beyond promotional pricing by checking customer reviews, the credibility of parent companies, business track records, and any history of complaints.
“Rushing into a decision based on price cuts can cause problems and higher costs after installation,” said Mr Poramate.

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