The Energy storage and technology for improving the efficiency of REPs in Vietnam

Mr. Tran Tue Quang - Deputy Director of Electricity Regulatory Authority of Vietnam delivered the opening speech at the workshop

At the workshop, the representative of the Office of the National Steering Committee for Electricity Development in his speech provided an overview on implementing the power source and grid projects in the national power development planning (PDP) and challenges during their deployment.

Workshop overview

Accordingly, Vietnam's power system is one of the power systems with a high growth rate in the world, reaching 9.6% in the period 2011-2020, although it decreased in 2020 due to the Covid-19 pandemic. By the end of 2020, the total installed capacity of Vietnam system reached 69,342 MW, of which solar power was 16,428 MW and wind power - 538 MW. Although the installed capacity is relatively high compared to the peak load, the system's available reserve capacity is quite low due to the seasonal nature of hydropower plants, the need for repair and maintenance of the thermal power plants and the uncertainty of wind and solar power projects.

Mr. Hoang Trong Hieu - Deputy Chief of the Office of the National Steering Committee for Electricity Development with the presentation on "Overview of the implementation of power source and grid projects in the national electricity development planning and energy sector renewables in particular; challenges in implementation"

The North has the highest load growth rate in the country at 9.3%/year in the 2016-2020 period, higher than the growth rate of power plants. The Central region has a much higher increase in capacity of the plants than the load growth, and the growth mainly comes from solar and wind power projects. The South consumes the largest electricity output, so even though the power supply increases, it still has to receive a huge amount of electricity from the inter-regional transmission system. In terms of capacity, the North has the highest peak load and it also increases the fastest.

Regarding the power grid, the system has 8,527 km of 500 kV transmission lines as the backbone of the national grid. A number of the 500 kV transformer substations supplying electricity to the North and the South is either full loaded or overloaded, related to the fact that many RE projects have been put into operation in the recent few years. Vietnam's electricity grid is already a modern type with the power loss target of the whole system reaching 6.42% (by 2020).

Mr. Nguyen The Huu - Head of Power System Department of Electricity Regulatory Authority with the presentation on" Amendment and supplement of technical regulations of energy storage system in regulations on transmission power system and power system distribution"

The government has issued many different incentive mechanisms for RE projects, including preferential FIT for up to 20 years with the incentives for corporate income tax, equipment import tax, land use and financial access. Therefore, by October 31, 2021, 3,980 MW of wind power and 16,428 MW of solar power including 7,755 MW of rooftop power projects were put into operation. The rooftop solar power projects mainly concentrated in the Center and South and grown too fast.

In recent years, a number of the large coal and imported LNG thermal projects in PDP VII were behind schedule and faced many difficulties. So the total capacity of these projects putting into operation in the 2016-2020 period was only 28,377 MW equal to 80% of the planned. The high rate of RE requires new developing the large reserve power capacity causing investment waste.

Ms. Tran Thi Thu Tra - Development Strategy Department of the Electricity of Vietnam with the presentation on "Solutions and proposed mechanism for developing energy storage systems in Vietnam"

An EVN representative added that according to the national energy strategic orientation, the rate of RE projects will reach 15% ÷ 20% in 2030 and 25% ÷ 30% in 2045 in the total primary energy supply. In which, the output of solar power and wind power expects to reach about 10 MTOE in 2030 (equivalent to 116.3 billion kWh or 21% of the whole system power generation).

The daily average generation of the wind power projects should be largely different between the months in the year. Specifically, in May the average daily wind power output is equal to only 25% of the daily average output in the highest month (December).

The lowest average capacity mobilized at 1 am in May only corresponds to 11% of the highest capacity mobilized at 1pm in December. That requires a huge reserve capacity if developing wind power as in the draft Power Plan VIII. Solar power projects cannot generate from about 6pm the previous day to 5am the next day, the output fluctuation is not much as the output in December is the lowest, equal to 70.5% of the output in April the highest month. The variable speed of solar power capacity is large, that estimates at 132 MW per minute by 2030.

Mr. Nguyen Minh Quang - Methodology Department of the National Load Dispatch Center with the presentation on "Operating renewable energy in Vietnam's power system"

In 2020, the Prime Minister assigned EVN to research an investment in energy storage solutions for the power system. From the point of view of the National Load Dispatch Center (A0), increasing the wind and solar power projects requires investment in technologies to increase flexibility, ancillary services (synchronous and asynchronous reserves) for voltage stabilization, frequency control. Besides, the need to transmit capacity of solar and wind power projects in peak hours increases partial overload of power grid and also increases need for peak-bottom displacement of the load diagram. A0 made an initiative in dispatching power grid overload as timely communication to power plant causing overload. The system inertia sometime is seriously decreased as it happened in 2021 New Year (Tet), that leads to load dismissal.

EVN representative divided energy storage technologies to 4 main groups: (i) thermal, (ii) mechanical, (iii) Electrochemical, (iv) Electrical and introduced Bac Ai pumped – storage hydropower plant including 4 units with a total capacity of 1,200 MW, a reservoir capacity of 9 million cubic meters, an efficiency of 80% and a total estimated investment level of 980 million US$. The project plans to be completed in 2028 with a special role in the national power system and but not simply accounted by buying and selling electricity amount.

Considering a need of energy storage system and consulting the international experiences, the Electricity Regulatory Authority (ERAV) proposed to supplement the technical standards of energy storage systems to the current regulations. Based on assessing the pilot energy storage battery systems, ERAV will ask the Ministry of Industry and Trade to amend, supplement and adjust the current regulations on connecting the energy storage battery systems.

Mr. Nguyen Viet Cuong - EVNNPT Technical Committee with the presentation on "Develop a reasonable transmission grid to ensure safe operation of renewable energy sources"

Regarding the transmission grid, Vietnam will complete circuit 3 of the 500 kV transmission lines in the PDP VIII. The problem of transmission grid development in the coming time is local overload in some areas of the power grid from 110 kV to 220 - 500 kV due to putting RE projects into operation. The RE projects operate with a Tmax of about 1,500 – 2000 hours per year while the traditional power plants operate with Tmax of 5,500 – 6,000 hours per year. So if continuing to develop RE projects as in period 2019-2020, the transmission fee may increase by 20 - 30%. That why, energy storage should help optimize the transmission system.

Mr. Nguyen Thai Son - Permanent member of the Scientific Council of Vietnam Energy Magazine with the presentation on "The role of the energy storage system and proposed mechanisms and policies"

The Scientific Council of the Vietnam Energy Magazine high considered the role of the energy storage system and asked the Government to make policy mechanisms for promoting investment in energy storage system at solar and wind power projects or in power system to avoid reducing RE capacity and waste of the social investment.

Danish expert Loui Algren with the presentation on "The Danish perspective on energy storage"

In his speech, Mr. Luis Algren, a Danish expert informed that the Danish power system currently does not install the energy storage systems, although it has 47% wind power capacity and 3% solar power capacity due to this system is strongly connected with Sweden and Norway power systems and Denmark considers Sweden and Norway systems as its power storage systems. However, Denmark makes strong use of the electricity price mechanism to encourage peak coverage.

Mr. Do Hoang Phuong - Representative of SMA Solar Technology AG in Vietnamwith the presentation on "SMA's solution to the problem of capacity reduction and grid stabilization for renewable energy projects in Vietnam"

The companies supplying the storage equipment for RE power projects as SMA Solar Technology AG, Shenzhen Growatt New Energy Co. Ltd., Solis Inverter, Hopewind Electric Co. Ltd. presented solutions for stabilizing the power grid, minimizing capacity reduce of the wind and solar power projects in Vietnam.

Mr. Pham Hung - Marketing Director of Growatt in Vietnam with the presentation on" Energy Storage Solution (ESS) of Growatt"

SMA provided storage and inverter solutions for many large RE projects in the world and also provided a still very new solution for producing hydrogen and ammonia.

Growatt offered the solutions for independent electricity supply combining inverter and storage for customers from a household to enterprise.

Mr. Nguyen Quang Tu - Vietnam Market Development Manager SOLIS INVERTER with the presentation on "Solis energy storage solutions"

Those are specific large-scale projects in the world that have been put into use with different technical features depending on the needs of RE investors, or power system operators.

Mr. Banh Quan Thang - Commercial Manager of HOPEWIND ELECTRIC in Vietnam with the presentation pn"Comprehensive energy storage solutions and products"

The Power Engineering Consulting Company 3 (PECC3) presented a concrete case of RE supply with energy storage system in Bach Long Vi island of Vietnam.

Mr. Nguyen Hoang Dung - Head of Renewable Energy Department PECC3 with the presentation on "Application trend of energy storage system (ESS) in Vietnam and case study of ESS application of PECC3"

Some comments expressed at the discussion session:

Dr. Nguyen Manh Hien - Scientific Council of Vietnam Energy Magazine

Mr. Le Truong Thuy - General Director of Mai Chau Hydropower Joint Stock Company

Representative of AES Company

All the opinions in the Workshop were united that energy storage is an important item for reducing CO2 emission in the power sector but there is a debatable issue that whom belong the costs of energy storage system.

The workshop participants united to propose the Government to learn experience from promulgating the mechanisms for solar and wind power projects in recent time to develop the policy mechanisms for energy storage systems in coming time.

Mr. Nguyen Anh Tuan - Permanent member of the Scientific Council of Vietnam Energy Magazine concludes the workshop

Concluding the workshop, the Standing Scientific Council of Vietnam Energy Magazine considered the indispensable trend of using energy storage in Vietnam, the energy storage research, test and application must be carried out. The Government should as soon as possibly promulgate regulations for the model of the energy storage market and the necessary economic-technic norms for developing RE power projects – the abundant energy sources of the country.