Tiếng ViệtWhen a solar power system is installed at a factory or workshop, grid connection becomes mandatory for the facility to synchronize with the national grid and register its surplus generation. This not only helps the enterprise harness renewable energy but also opens up the possibility of selling surplus electricity, creating an additional revenue stream.
The use of a bi-directional meter is a key component in completing this technical and legal process. The meter measures both the electricity drawn from the grid (consumption) and the electricity exported from the solar system (export)—thereby ensuring data transparency and protecting the interests of both the enterprise and the distribution utility.
New 2025 Technical Regulations Businesses Must Know
According to Decree 58/2025/ND-CP and guiding documents from Vietnam Electricity (EVN), rooftop solar power systems connecting to the grid must comply with the following regulations:
- The connection system must feature a bi-directional meter that is compliant with measurement standards and capable of continuous data transmission, ensuring transparency of all electricity purchased and sold.
- For rooftop solar systems eligible for grid connection, the surplus electricity exported to the grid must not exceed 20% of the total monthly generated output.
- The metering system must have remote data transmission capabilities (as a “smart meter”) and meet “smart-grid” requirements. Under the roadmap to 2030, traditional mechanical meters will be gradually phased out.
- The connection application procedure includes: submitting a technical file (drawings, equipment specifications), a connection point survey, signing a power purchase agreement (if surplus power is sold), technical commissioning, and finally, grid synchronization.
The Technical Process Businesses Need to Understand
To ensure the system is grid-tied and metered correctly, the following steps are crucial:
Step 1: Register the Connection Request – The business submits an application to the local power utility, including proposed capacity, connection point, and preliminary diagrams.
Step 2: Survey & Technical Agreement – The power utility inspects the transformer, power lines, and distribution capacity to determine a suitable connection point.
Step 3: Install Bi-directional Meter & Metering System – The meter is installed at the connection point to accurately measure all purchased and exported electricity.
Step 4: Commissioning and Grid Synchronization – Verify voltage, current, performance, and connections, then sign the official acceptance record before synchronizing with the grid.
Step 5: Monitoring and Reporting – The business must ensure metering data is transmitted to the power utility’s management system and is available for internal reports and ESG documentation.
Specific Benefits of Following the Correct Procedure
When a solar power system is connected and metered to standard, the business can legally and transparently sell surplus power exported to the grid. The bi-directional meter provides an accurate record of consumption and generation, which is the basis for EVN to pay for the renewable energy, creating a stable new revenue stream for the business. This also helps shorten the investment payback period, increasing the project’s economic efficiency.
The data recorded by the bi-directional meter helps the business monitor system performance and serves as a basis for ESG reports and energy audits. A valid commissioning and connection record is a mandatory legal condition for the system to be allowed to synchronize with the grid and operate stably. By strictly adhering to the process, businesses not only ensure technical safety but also avoid the risk of penalties or operational disruptions due to non-compliance.
Businesses should prioritize partnering with contractors or EPC units who have experience implementing solar power projects and a firm grasp of EVN’s connection and commissioning procedures. A professional partner will assist the business in completing all technical documentation, detailed drawings, and ensuring the grid synchronization process is safe, secure, and legally compliant.