Vietnam's Self Consumption Solar Rules — What EPCs Should Know

The Two Categories Under Decree 135 and Decree 58

Vietnam's current rooftop solar regulatory framework distinguishes between two types of installations:

Category 1: Self consumption systems with no grid connection

These are rooftop solar systems that serve only the owner's own electricity needs and are not connected to EVN's grid. There is no surplus sale, no bidirectional meter, and no grid interaction at all. Under Decree 135, these systems are subject to minimal regulation. No EVN approval is required before installation. The owner simply installs the system and begins using it. This is the lightest regulatory pathway available and the one that the government has actively promoted for rapid deployment.

Category 2: Grid-connected systems that sell surplus to EVN

These systems are connected to the EVN grid and can export surplus generation up to the current 20% cap (with a potential rise to 50% under the proposed amendment). These systems require prior registration with the local electricity authority and installation of a bidirectional meter by EVN. The connection process involves more steps and takes longer than the entirely self consumption pathway.

The Self Consumption Pathway — Step by Step

Step 1: Owner decision and EPC contract

The property owner decides to install solar for self consumption. No government approval is needed before starting. An EPC contract is signed and installation begins.

Step 2: Installation by a licensed electrical contractor

The system is installed by a contractor with an electrical installation licence. Equipment must meet Vietnamese technical standards. No pre installation inspection by EVN is required for systems below the registration threshold.

Step 3: Post installation registration

Under Decree 135, owners of systems above a certain capacity threshold must register their installation with the local Department of Industry and Trade (DoIT) within 30 days of commissioning. Systems below the threshold have lighter reporting requirements. The registration requires basic technical information: system capacity, panel specifications, inverter specifications, and installation address.

Step 4: Operation

The system begins operating and reducing the owner's electricity bill immediately. No EVN inspection is required for the self consumption pathway, and no bidirectional meter is installed. The owner simply consumes less grid electricity as a result of their own generation.

Why the Self Consumption Route Is the Default Recommendation

For most Vietnamese residential and commercial clients, self consumption is the better financial structure — regardless of the surplus sale cap. The reason: the price EVN pays for surplus (in the range of VND 670 to 1,000 per kWh) is significantly lower than the retail rate the client pays to buy electricity from EVN (which ranges from VND 1,806 per kWh for the lowest residential tier to over VND 3,460 per kWh for higher commercial tiers).

Every unit of solar electricity the client consumes directly avoids a grid purchase at the higher retail rate. Every unit exported to EVN is sold at the lower avoided cost rate. The financial value of self consumption is therefore 2 to 5 times higher than the value of exporting the same unit. A solar system sized to cover 80 to 90% of the client's daytime consumption is almost always the most financially optimal configuration, regardless of what the surplus export cap is.

The Government Priority — 10% Target

Vietnam's Prime Minister has issued a directive setting a target of solar panels on 10% of government buildings and 10% of households by the end of 2026. This directive has been backed by specific implementation requirements for government agencies and incentive communications for households. For EPCs, this government push means two things: increased consumer awareness and inquiry volume, and potential acceleration of the regulatory improvements that would make residential solar even more attractive.

The directive also creates a specific opportunity in the government building segment. Ministries, hospitals, schools, and other government facilities have been given explicit solar installation targets. The procurement process for government solar projects in Vietnam is typically through competitive tender. EPCs who are registered with the relevant government procurement platforms and who have track records of completed commercial installations are positioned to participate.

Frequently Asked Questions

Q1. What is the DolT and why do I need to register with them?

The Department of Industry and Trade (Sở Công Thương) is the provincial government body responsible for regulating electricity and renewable energy installations at the provincial level. Under Decree 135 and Decree 58, rooftop solar installations above the minimum capacity threshold must be registered with the local DoIT within 30 days of commissioning. The registration confirms technical compliance, records the installation in the provincial renewable energy database, and gives the owner formal documentation of their solar asset. Failure to register does not typically prevent operation of the system in the short term, but may create complications with future grid connection applications or property transactions. The registration process is straightforward and typically handled through the provincial DoIT's online portal or in person office submission.

Q2. Can a self consumption system be upgraded to grid connected later?

Yes. A rooftop solar system installed purely for self consumption can be upgraded to a grid connected system later by applying to the local electricity authority for a grid connection and having EVN install a bidirectional meter. This upgrade requires an application showing the existing system's technical specifications and compliance with grid connection requirements, including appropriate inverter anti islanding protection. If the client's inverter is already grid interactive (which most modern string inverters are), the upgrade process is primarily administrative. If the proposed 50% surplus sale cap is adopted and improves the financial return on grid export, many clients who installed purely for self consumption may choose to make this upgrade at that point.

Sources

• MOIT Vietnam — moit.gov.vn — Decree 135/2024/ND-CP and implementing circular (Decree 58) — rooftop solar installation, registration, and grid connection rules
• RECS International — recs.org — Vietnam country profile — rooftop solar regulatory framework, EVN purchase rates, Decree 135 overview
• Vietnam Briefing — vietnam-briefing.com — Vietnam rooftop solar 2026 — self consumption pathway, DoIT registration, PM directive target