Rooftop solar procedure under Decree 58/2025 in Vietnam

According to MOIT guidance at implementation conferences, the host building must have valid construction legal status; adding a rooftop system must not conflict with the building records and must maintain structural, electrical and fire safety.

• Legally built structure with a roof — or a house-like structure — able to carry the array.
• System capacity matched to on-site electricity demand.
• Respect the voltage level and current limits of existing metering equipment.
• Electrical safety, lightning protection and fire safety documents updated for the added scope.

Decree 243/2026/ND-CP widened the scope to systems installed on structures shaped like a house, not only on roofs of conventional buildings.

Depending on capacity and whether the system connects to the grid or exports, it may only require a notification or may need development registration with the competent authority. Identify this at design stage because it drives the schedule.

• Step 1 – Survey the roof, measure load, set capacity and decide whether any export is allowed.
• Step 2 – Determine the applicable route (notification or development registration) by capacity and connection mode.
• Step 3 – Contact the local power utility for connection and operating guidance.
• Step 4 – Build, test, commission and complete operating documentation.
• Step 5 – Archive legal records, acceptance reports and generation data for later reporting.

Exact capacity thresholds and document lists depend on the legislation and on local utility guidance; verify them before starting.

The policy direction prioritises on-site consumption and limits export. At the implementation event in Bac Ninh, a MOIT representative stated that self-production, self-consumption systems may sell surplus electricity up to 20% of generated output under the applicable rules.

• Non-exporting systems typically use zero-export devices and load-following control.
• Systems selling surplus must agree terms with the power utility and stay within the regulated limit.
• Adding storage absorbs surplus instead of exporting it, which suits plants with shifted load.

The 20% figure follows statements and guidance published on moit.gov.vn; conditions, pricing and procedures for surplus purchase follow the applicable regulations and are not an Orca Energy commitment.

• Sizing capacity above on-site demand, creating export that is not permitted.
• Ignoring limits of the existing meter and connection voltage level.
• Construction and fire safety records not updated for the rooftop addition.
• Missing equipment documentation (certificates, inverter data) in the first submission.
• Discovering only during construction that development registration was required.