Pressure caused by renewable energy sources
Mr. Vu Xuan Khu - a Deputy Director of NLDC said that Vietnam's power system has encountered a new challenge, i.e. a large number of solar power plants are coming into operation from now until June 30, 2019. However, these energy sources are generally unstable in power generation, which consequently will cause many difficulties in power system operation.
Speaking more specifically about this issue, Mr. Khu articulated: Because the power generation of a solar power plant changes instantly subject to weather conditions, those in the same area tend to swing, then lead to a simultaneous change in a large amount of power, which is an inherent risk exposed to the stability of power system. For example, Phong Dien solar power plant has a power generation variation of over 60% in a short time just 5-10 minutes, as a result the power system operation needs to be proactive and flexible to respond promptly to a very quick rise – fall in power.
In addition, how to both operate renewable energy power plants and secure not to cause overloading of power lines and transformers, especially in the areas of Ninh Thuan and Binh Thuan provinces, also puts substantial pressures on system operators. In fact, while solar power plants and wind farms are growing massively like mushrooms, the transmission grid system cannot grow up at the same speed and overload situations have occurred.
NLDC has been taking the initiative to work out solutions for operating the power system in a safe, reliable and economical manner in 2019
Improving the quality of load forecasting
In order to ensure the safe and efficient operation of power system and electricity market, NLDC has proactively developed yearly and monthly energy balancing plans, with the aim of establishing proper real-time dispatching plans. According to Mr. Vu Xuan Khu, NLDC has developed time-based operation plans, both short-term and long-term. At the same time, the calculation cycle has dropped from 1 hour to 0.5 hours at all stages, including the operation of power system and electricity market; power system operation modes, generation dispatching modes, especially the forecast of renewable energy generation has been regularly established, enabling the power system to operate in line with actual contexts and fuel supply situations; coal and gas supply capacity has been closely monitored. Thereby, NLDC has recommended to EVN appropriate and economical dispatching modes, in compliance with regulations of the electricity market.
NLDC has worked intensively with power generation units, creating the best conditions to bring new power generation plants into operation on schedule, especially solar power projects. Recently, A0 has strengthened their working time in 3 shifts, even on holidays; arranging additional personnel to support centers with high work pressure such as: The Central Load Dispatch Center, the Southern Load Dispatch Center, etc. to provide the best support to solar power projects coming into operation before June 30, 2019.
During peak months, NLDC has established a special daily operation mode, based on scenarios of simultaneously high growing loads in all three regions, to be ready to respond in the event of prolonged and extensive heat wave occurrence. NLDC has collaborated with transmission and distribution units not to carry out works on the grid during hot days, reducing the threat of overloading of the remaining elements.
Over the past time, the Center has cooperated with power corporations in performing Load Adjustment Programs, cooperated with relevant organizations to put into operation EMS/Scada systems, improving signal collection in the best way with better quality and reliability, supporting system operators in real-time decision making. The Center has step by step mastered new operation monitoring systems such as fault recording, wide area protection, power quality monitoring, etc.
National and regional load dispatchers will also constantly calculate and evaluate impacts on revenue of power generation units, cost of purchasing electricity of purchasers, etc.; operating the competitive generation market in a fair and transparent manner, securing the operation of power system in the most economical and effective way; giving reasonable answers to any claims or complaints.