Hanoi accounts for about 15 per cent of Vietnam's electricity demand, with consumption expected to continue rising through 2030 as urbanisation, population growth and expanding business and production activities drive demand.

The city has few large-scale power sources of its own and relies largely on electricity transmitted from elsewhere, putting pressure on transmission and distribution networks, particularly during peak demand.

Under the draft, households installing rooftop solar would receive VND 1 million per kilowatt-peak (kWp) of installed photovoltaic capacity, capped at VND 3 million per household. Eligible systems must have a capacity of at least 1 kWp.

Households adding battery storage would receive VND 1 million per kWh, capped at VND 3 million, for systems of at least 2 kWh. Combined rooftop solar and storage subsidies could reach VND 6 million.

Each eligible home would receive support only once, and households would have to operate the system for its intended purpose for at least three years. The subsidy would not exceed actual eligible costs after deducting any other state support.

Funding would come from the city budget, with commune authorities handling applications and subsidies. Households using fraudulent documents, misusing systems or removing them early would have to repay the full subsidy.

Hanoi has average solar irradiation of about 1,329 kWh per square metre annually, offering potential for rooftop generation without requiring additional land. Battery systems could store surplus daytime power for use in the evening.

Vu The Thang of Hanoi Power Corporation said households should size rooftop solar systems based on actual electricity demand, particularly daytime use.

Households should also consider roof conditions, grid connections and plans for surplus power. Those using more electricity at night should weigh the cost and payback period of battery storage.

Homeowners would be responsible for electrical and fire safety, structural integrity and environmental protection, while the city would set technical standards and oversee equipment quality and installers.