Renewable energy development: Challenge in operating Viet Nam’s power system

The nature of renewable energy (RE) always contains uncertainties and they will be a big challenge in operating the Viet Nam’s Power system when added to the competitive electricity generation market. A reporter from Electricity Magazine had an interview with Mr. Nguyen Duc Cuong - Director of the National Load Dispatch Centre (A0) about this issue.

Mr. Nguyen Duc Cuong

Reporter: When RE is developed, which are advantages and disadvantages for operating power system, sir?

Mr. Nguyen Duc Cuong: Under the adjusted Electricity master plan VII, by 2020, Viet Nam’s power system shall consist of 800MW of wind power and 850MW of solar power, which will continue to be increased in the coming years. The development of RE along with preferential incentive mechanisms will attract domestic and foreign investors, thereby reducing the pressure on arranging investment capital for the construction of power source works. Particularly, solar and wind power projects are mainly concentrated in the South and South Central Coast - the area with power load accounting for about 50% of the whole country. Therefore, RE development will contribute to reducing power shortage in the South, improving security of power supply and reducing the tension in operating the power system.

Apart from the positive aspects, RE also causes many difficulties in operating the power system. Particularly, with the total dependence of generation capacity on primary energy source in uncertainty as RE, the stability of the system will generally be affected if traditional power sources are not timely adjusted in line with the change in capacity of load and power source from RE.

As calculated, capacity use coefficient of RE sources (wind, solar) in Viet Nam is only about 18-20%, significantly lower than that from source of coal-fired heat by about 75% and hydropower by about 40-50%. Additionally, if RE is deeply involved in the system, the operation shall face the following challenges: The quality of power also tends to decrease, the phenomena of voltage exceeding the regulated value will further occur, particularly in areas with many sources and being far from load center, the process of system imbalance tends to faster and more strongly happen.

In the next three to five years, the development of solar power projects may exceed the loading capacity of existing power grid. Operation limitation of equipment in such areas with large potential for solar power as Ninh Thuan, Binh Thuan, Phu Yen, Khanh Hoa, etc., will be repeatedly violated, destabilizing the system, causing danger for equipment and generating many technical problems that the load dispatch levels have to be handled.

Reporter: What should be done to “solve” above-mentioned difficulties, challenges, sir?

Mr. Nguyen Duc Cuong: One of the largest challenges in the operation of RE sources is the uncertainty of generation capacity. In order to mitigate this impact, Viet Nam Electricity assigned A0 Centre to develop a short-term renewable energy forecasting system. The system will forecast the generation capacity of RE sources based on forecast information from hydro-meteorology, weather, operational characteristics and actual operating time of RE plants. Thereby, A0 Centre will prepare options to proactively plan for mobilization of RE power sources and plans to mobilize other support sources to control the frequency of power system. If the forecasting is properly performed, the power system will be stably, safely and economically operated.

Reporter: Is it difficult to develop a renewable energy forecasting system?

Mr. Nguyen Duc Cuong: This is a completely new system, A0 Centre has not had much experience, the implementation also faces many challenges. In addition to efforts made by A0 Centre, there should be the participation of other units such as: The unit providing high quality meteorological forecast service, ensuring reliability; the unit owning RE plant, etc.

 Currently, A0 Centre has actively exchanged and learned international and regional experiences on RE forecasting; assigned specialist, engineers to participate in conferences, workshops and intensive training courses on forecasting; connected with providers of solutions and infrastructures for RE capacity forecasting to learn about and set up to develop a forecasting system at A0 Centre.

At the same time, A0 Centre also proactively develops technical requirements for forecasting deployment, seeks for domestic and foreign meteorological forecast service providers, ensuring possibility of providing information on radiation, temperature, wind speed forecasts, etc., to serve planning and regulating power system; propose the Group, the Electricity Regulatory Authority of Viet Nam, the Ministry of Industry and Trade on adjusting and supplementing Circulars, procedures and regulations on investment obligations of monitoring system, forecasting and supplementing the list of signals that should be provided on Load dispatch levels.

Reporter: With uncertainty of RE source, was developing RE forecast system enough to ensure safe, stable operation of the national power system, sir?

Mr. Nguyen Duc Cuong: This is just one of the necessary factors for National Load Dispatch Centre to take initiative in planning the mobilization of power at each time. However, in order to safely, stably and economically operate the power system when RE develops, there is much work to be done.

A0 Centre has focused on bringing its regulations to full strength and organizing the control of current power system’s frequency. Particularly, A0 Centre has requested the Viet Nam Electricity and the Electricity Regulatory Authority of Viet Nam to update the methodology in determining the frequency modulation capacity and rotation reserve in the direction of more specific and detailed calculation for the power grid operation modes; reviewed the current status of frequency control in the system, coordinated with power generation units nationwide to test for adjusting the controlling frequency of automatic system, voltage; required to set up parameters and put into operation.

A0 Centre has also conducted study on new frequency and voltage control options on power system to support renewable energy integration. Currently, A0 has coordinated with the United States US Agency for Trade and Development to study on energy storage systems, etc., to continue promoting training and quality improvement of human resources; studied and learnt experiences from countries in the world with developed RE sources.

Reporter: Along with the efforts made by the Power sector in general, A0 Centre in particular, in your opinion, what should be done by the State as well as investors to ensure security of the power system when RE is intensively involved in the system?

Mr. Nguyen Duc Cuong: The investors should comply with standards as stipulated in selecting investment equipment for solar power plants. At the same time, they should closely coordinate with load dispatch levels in the technical agreement, energization in connection point, testing and acceptance as well as commercial operation of the system. Particularly, it is necessary to select areas that are capable of releasing capacity for developing projects, etc.

For State agencies, they should early issue a national solar power development plan, in which, issues of capacity releasing, technical requirements attached to incentive mechanisms, appropriate proportion of RE, ensuring a safe, stable and efficient operation system should be carefully taken into consideration.

Reporter: Thank you so much, sir!

  • 15/11/2018 04:20