Rapid Shutdown Devices and Risk Reduction in Rooftop Solar Power Systems According to EIT Standards

The 2022 Engineering Institute of Thailand (EIT) standard for rooftop solar power systems in Thailand mandates that rapid shutdown devices be installed, particularly to reduce voltage within the array boundary to no more than 80 volts within 30 seconds. This requirement has led to a significant transformation in the solar power industry in Thailand, especially for solar power systems ranging from 200 kW to less than 1,000 kW, which are exempt from requiring an energy business license but must apply for a controlled energy production permit. The Department of Alternative Energy Development and Efficiency (DEDE) is responsible for overseeing compliance based on the EIT standard.

As a result, solar power systems of 200 kW and above must install rapid shutdown devices as specified by the EIT standard (which do not specify a minimum system size required for rapid shutdown installation). Currently, the solar power industry is focusing on procuring module-level rapid shutdown devices, which are installed behind solar panels to reduce voltage within the array boundary, ensuring compliance with EIT standard. Available configurations include one module per panel or one module per two panels. When the EIT standard was first introduced, awareness and understanding of rapid shutdown devices were still very limited, and only a few suppliers were present in the domestic market. As a result, DEDE postponed the enforcement of the EIT standard until July 2026 to allow businesses more time to source and install the necessary equipment in compliance with the standard.