Vietnam's new decree lets rooftop solar sell up to 50% of excess power

The Vietnamese government issued Decree 243/2026, amending earlier Decrees 57 and 58, to create a formal mechanism for selling surplus electricity from rooftop solar installations to the national grid. The decree sets a default cap of 50% of the electricity generated by a rooftop system that can be sold, with the possibility of exceeding this limit after 31 December 2030 if the grid has sufficient capacity.

Pricing for the excess electricity is calculated based on the average market electricity price of the preceding year, but it cannot exceed the solar tariff ceiling established by regulators. Payments are made according to the contracted amount, or the actual measured output if it differs. The rules also apply flexibly to mountainous and island regions without grid connections, removing the 50% cap in those areas.

Vietnam currently has about 103,000 rooftop solar systems with a combined capacity of over 9,500 MW. The amendment supports the country's goal that by 2030, half of office buildings and households will generate their own solar power, easing pressure on the transmission network and boosting renewable energy adoption.