Vietnam's economy is rapidly expanding, accompanied by a surge in energy demand. This problem presents numerous difficult obstacles when principal energy sources such as coal, oil, gas, and etc., have been depleted, leaving insufficient for domestic consumption, and hydroelectricity has been fully utilized. Just around 2.7 GW of large hydropower over 30 MW is supposed to come into operation between 2021 and 2025, with another 2.8 GW of small hydroelectricity still under construction. As a result, renewable energy development is an unavoidable trend and an essential additional supply for the electrical network, particularly for power supply to the South. This type is becoming increasingly significant.
The energy storage system's importance in the operation of Vietnam's power grid
Between 2019 and 2020, Vietnam saw rapid growth in renewable energy (RE), particularly solar and wind power. By the end of 2020, 16,700 MW of solar power capacity (including rooftop solar power) has been linked to the national electricity supply (accounting for 24 percent of the system's overall capacity). When the overall capacity of hydroelectric plants in operation (20.7 GW) is calculated, renewable energy accounts for 55.17 percent of its power system's total capacity.
The development context of non-hydro renewable energy in 2019 and 2020:
In 2019, total installed capacity of nationwide power sources achieved 55,231 MW, increasing 6,701 MW; total electricity output is 240.1 billion kWh; commercial electricity demand reached roughly 209.8 billion kWh, a 9.05 percent increase over 2018. (in which the South increased by 8.3 percent ) [1]. Electricity usage surged dramatically, particularly during the hot months between June and August. Drought happened in many locations, causing the water volume in hydropower reservoirs to be shallow, and hydropower output fell by 16.3 billion kWh compared to 2018. By the end of 2019, the total volume of water kept in hydroelectric reservoirs was 11 billion m3 short compared to the entire reservoir. There are almost no provisions in the electricity system. Central Power Corporation's (EVNCPC) total commercial electricity in 2019 obtained 72,671 billion kWh, up more than 9% compared to 2018 [2] (accounting for 34.6 percent of the entire national electricity demand), despite the fact that only an expanded Vinh Tan 4 coal-fired power source (600 MW) came into operation and the expanded Duyen Hai 3 coal-fired power plant (688 MW) had been initially connected to the grid at the end of the year. To supply electricity to the South, the system needed to mobilize 1.8 billion kWh of oil-fired power sources.
On the other hand, 2019 saw a significant expansion of renewable energy sources, particularly solar power. Solar power has increased more than 54 times from only 86 MW in 2018 to 4,696 MW in 2019. Electricity generation hit 4.932 billion kWh (in 2018, the output was only 22 million kWh). Along with energy generated by wind power sources (723 million kWh), biomass electricity 410 million kWh, and non-hydro renewable energy sources have contributed 6.065 billion kWh to the system.
According to EVN's assessment, the power transmission trend from the North to the Central and the Central to the South is still the dominant inter-regional transmission trend in the 2016-2018 period. However, by 2019, when the South was enhanced with a new power source, especially the renewable energy source, the transmission power on the inter-regional 500 kV transmission line had drastically dropped. Especially during the summer of 2019, when the North and Central of Vietnam raised their load owing to scorching and the high deployment of solar power plants, transmission has shifted from the South to the Central and North.
Renewable energy sources are focused on developing in the South with a total capacity of solar power reaching 3,491 MW and wind power of 288 MW in 2019, making an essential contribution to compensating for the electricity shortfall caused by delayed power sources here. However, due to the rapid growth of solar power, power grids in some places were unable to be created swiftly, resulting in transmission congestion and challenges in regulating and managing the system at a high or low point. The system has to reduce the generating capacity, only ensuring the release of 4,200/4,880 MW of renewable energy sources being put into operation.
At the end of 2020, the total installed power capacity of the whole system reached 69,300 MW, increasing 14,000 MW compared to 2019, of which renewable energy sources rose 11,780 MW. The entire system's electricity output hit 247.1 billion kWh, growing only 2.9% compared to 2019. National commercial electricity achieved 216.95 billion kWh, increasing 3.42% compared to 2019. The electricity demand has slowed down due to the Covid-19 pandemic's impacts. In 2020, non-hydroelectric renewable energy sources contributed 12,203 billion kWh, accounting for 4.9% of the electricity produced in the whole system, of which solar power produced 10,877 billion kWh, accounting for 4.4%. For the South, the total commercial electricity in EVNCPC's 21 provinces in 2020 reached 75.438 billion kWh, only increasing by 3.8% in 2019 [2].
It can be seen that the additional power capacity in 2020 is primarily from renewable energy sources, with solar power reaching 16,700 MW in 2020, accounting for 24% of total system source capacity. In 2019, the entire country had only 272 MW of rooftop solar power, but by the end of 2020, it would have reached over 7,780 MW, accounting for nearly half of the total capacity of solar power sources. Southern Electricity Corporation (EVNSPC) had the highest total capacity of rooftop solar power sources in the country, at 5,658 MWp. Ho Chi Minh City Electricity Corporation's location had a total capacity of roughly 365 MWp.
At the end of August 2020, 52 solar power plants in the South have been energized and put into operation, with a total installed capacity of 2,584 MWp. Solar power plants in the South contributed over 2.26 billion kWh (in the eight months of 2020), accounting for 4.43% of the total electricity output of the Southern power system.
In contrast to the features indicated above for 2019, load growth in 2020 was the lowest in more than a decade, owing primarily to the Covid-19 pandemic. Simultaneously, enterprises and individuals have massively expanded solar power sources to meet the time restriction for enjoying the incentive mechanism of solar power (according to Decision 13/202020/QD-TTG of the Prime Minister). However, the new capacity added in 2020 is focused in the final months of the year, so the main impact will occur in 2021. Although this year has seen a sluggish rise in electricity demand due to the insignificant additional traditional electricity, the amount of renewable energy has contributed to supplement power supply for the South, especially at the noon peak time of the load.
Solar and wind power development in the South in 2021:
Presently, the installed capacity of non-hydro renewable energy sources nationwide exceeds 18,000 MW and is expected to surpass 23,000 MW by the end of 2021.
According to EVN, by July 2021, enterprises will have signed a power purchase agreement (PPA) with EVN, including 144 wind power plant projects with a total capacity of more than 8,144 MW. Based on investors' progress reports, 21 wind power plants with a combined capacity of 819 MW have been put into commercial operation as of the start of August 2021. Before October 31, 2021, 106 wind power plants with a combined capacity of 5,655.5 MW are expected to go into commercial operation [3].
Regarding rooftop solar power, by July 24, 2021, 104,282 projects will have been installed with a total capacity of 9,580 MWp, generating 3,074 billion kWh to the grid; the calculated emission reduction is 3,263,122 tons of CO2. The majority of rooftop solar power installations are in the South, where there is a source of solar radiation and a large number of sunny hours.
1/Rooftop solar power:
The overall number of clients building a rooftop solar power with a total installed photovoltaic panel capacity of 5,523 MWp operation at the end of June 2021 is 54,062 (equivalent to 4,417.6 MW). In the first 6 months of 2021 EVNSPC acquisition of 3,189 billion kWh of rooftop solar electricity from consumers.
Ho Chi Minh City is also a location where solar power plants are significantly developed. In the first six months of 2021, EVN Ho Chi Minh city produces roof solar electricity from its consumers on the grid of 135 million kWh..
2/ Farm solar power plant:
By the end of June 2021, 66 farm solar power plants with a total installed capacity of 3,281.35 MWp will be operational in 9 provinces: Binh Thuan, Tay Ninh, Long An, An Giang, Ba Ria - Vung Tau, Ninh Thuan, Binh Phuoc, Hau Giang, Vinh Long.
The electricity generated by the solar energy plants in June 2021 came down by 396,03 million kWh, down 3,36 percent from May 2021 (increased 61.73 percent over the same time (244,87 million kWh) (excluding self-use and rooftop solar power of customers). In the first six months of the year, the overall energy production from solar plants is 2,452 billions of kWh, representing 6,01 percent of electricity received across the South.
3/ Wind power plant:
By the end of june 2021, 15 wind power plants were constructed in four provinces: Binh Thuan, Ninh Thuan, Bac Lieu and Ben Tre with a total installed capacity of 754,13 MWp.
The electricity generated by wind energy plants in June 2021 amounted to 69.73 million kWh, accounting for 1,04% of the system's total power generation. The electricity received from wind power plants accumulated over the first six months of 2021, is 588.53 million kWh, which accounts for 1.54 per cent of the entire system'S total electricity generation (excluding customers' self-consumed electricity).
The South's power usage reached 39.666 billion kWh in the first 6 months of 2021, a rise of 8,98% over the same period of 2020, according to EVNSPC (electricity consumed in the first 6 months of 2020 reached 36.40 billion kWh. kWh). In particular, renewable energy output reached over 6.229 billion kWh (588.53 million kWh, 3.189 billion kWh of rooftop solar power, and 2.452 billion of agricultural solar power plants), respectively.
Therefore, the total energy utilized by solar and wind power during the first six months of 2021 in EVNSPC accounts for 15,7%. Clearly, the electrical supply in the South has been supplied with substantial quantity from renewable energy.
The power generated and imported in the complete system was accumulated in the first six months of 2021 according to EVN, up 7.4% by 2020, which amounted to 128,51 billion kWh. In which the mobilized power output of some of the principal power sources is proportionate to the overall power supply of the entire system:
- Hydropower achieved 30.46 billion kWh and represented 23.7%.
- Coal thermal power achieved 51.9 per cent of 66.67 billion kWh.
- Gas turbines amounted, for 12.2%, to 15.66 billion kWh.
- Non-hydropower deployed renewable energy amounts to 14.69 billion kWh (wind, solar, biomass) or 11.4%. In which only 6.364 billion kWh of wind power and solar power are contributed by the southern area. [*].
-The power imported totaled 624 million kWh, or 0.5%
- The thermal power of mobilized oil reaches 2 million kWh.
When a set of wind power plants are placed into service by the end of this year, up to 23,000 MW of renewable energy, this pattern remains until the hot season when hydro-electricity reservoirs peak. Lowest water level (water storage preparation time), not creating sufficient capacity.
Renewable energy's contribution to the Southern region's electrical supply is becoming increasingly essential. As of the first six months of 2021, the South's electricity output from wind and solar power sources was 6.364 billion kWh, accounting for 43.3 percent of the country's total renewable energy (non-hydroelectricity) production. It is expected that by October 30, 2021, when 119 wind power plants with a total capacity of 5,655.5 MW will be put into operation to enjoy preferential prices (according to Decision No. 39/Q-TTg,10/9/ 2018 of the Prime Minister on the mechanism to support the development of wind power projects in Vietnam) [4,] the proportion of electricity produced from renewable energy will have increased.
Source:nangluongvietnam.vn