1. Current status of solar power development in Vietnam

- According to experts at the Vietnam Clean Energy Association, our country is located in the tropical monsoon region.The place with the most amount of sunlight shining in the top on the world solar radiation map. On average, in our country, the annual amount of solar radiation will range from 4.3 to 5.7 million kWh/m2.In which areas such as the Central Highlands and the South Central Coast, the number of sunshine hours will be from 2000 to 2600 hours per year. The average amount of solar radiation is about 150kcal/m2, accounting for about 2000 to 5000 hours per year.

- Accordingly, it is estimated that the theoretical potential of solar power is about 43.9 billion TOE. According to the prospect and plan given in 2020, it is expected to exploit solar power about 850MW. By 2025, the total exploited solar power is estimated to increase to 4,000MW. And it is expected to achieve 12,000MW of electricity from solar energy in 2030.

2. Mechanisms and policies for solar power development

According to Decision No. 2068/QD-TTg dated November 25, 2015 of the Prime Minister, the objectives and development orientation of solar energy are as follows:

- Objectives: the strategic objective is to increase electricity production from renewable energy from about 58 billion kWh in 2015 to about 101 billion kWh in 2020, about 186 billion kWh in 2030 and about 452 billion kWh in year 2050. Proportion of electricity produced from renewable energy in the total electricity produced nationwide will increase from about 35% in 2015 to about 38% in 2020, about 43% in 2050.

- Orientation for the development of solar energy sources:

Developing solar power to supply electricity to the national electricity system and border areas, islands, remote and isolated areas where electricity cannot be supplied from the national grid.

Electricity produced from solar energy will increase from about 10 million kWh in 2015 to about 1.4 billion kWh in 2020; about 35.4 billion kWh in 2030 and about 210 billion kWh in 2050. Bring the proportion of electricity produced from solar energy in total electricity production from negligible to about 6% in 2030 and about 20% in 2050.

In addition, according to the Prime Minister's Decision No. 428/QD-TTg dated March 18, 2016 approving the adjustment of the national electricity development planning for the 2011-2020 period with a vision to 2030.Regarding the development orientation of power sources, in which: Accelerate the development of power sources using solar energy, including concentrated sources installed on the ground and distributed sources installed on roofs: Bring the total capacity of solar power sources from the current negligible level to about 850 MW in 2020, about 4,000 MW in 2025 and about 12,000 MW in 2030. Electricity produced from solar power accounts for the proportion of Approx. 0.5% in 2020, About 1.6% in 2025 and About 3.3% in 2030.

3. The need for investment

Based on the national electricity development planning for the period 2011-2020, with a view to 2030, the adjustment and approval in Decision No. 428/QD-TTg dated March 18, 2016 of the Prime Minister, the electricity load forecast by 2030 as follows:

Note: Pmax is the maximum power of the power system. Power output SX = Pmax*24h.

With electricity demand growing by about 10% per year, Vietnam needs to add about 3,500-4,000 MW of new power capacity each year.In the condition that traditional power generation sources are close to the limit point such as hydroelectricity (there is not much room for development), thermal power (construction progress of thermal power plants is slow compared to the plan, no active source of electricity, etc.). coal supply ...), nuclear power has stopped construction, the development of renewable energy sources is being encouraged by the government.

Vietnam is located in the equatorial belt, which is considered to have a high solar potential compared to other countries in Asia.

According to domestic survey documents, the average total solar radiation in Vietnam is about 5.7 kWh/m2/day in the central and southern provinces, and about 3.3 kWh/m2/ days in the northern provinces. From below the 17th parallel, solar radiation is not only abundant but also very stable throughout the year, decreasing by about 20% from the dry season to the rainy season.

The number of sunshine hours per year in the North is about 1500-1700 hours while in the Central and Southern Vietnam, this number is around 2000-2600 hours per year.

4. Solar panels and inverter

- The most important elements of solar power projects are photovoltaic panels, and power converters.

- Solar panels have the function of converting sunlight to electricity.

- Inverter is the converter from the power of the panels to the appropriate voltage to connect to the grid.

 Photovoltaic panels and inverter

5. Principle of solar power plant

- Using an inexhaustible source of energy is the sun, which is absorbed by photovoltaic panels and converted to DC power.Because the power source of each of these panels has a small potential, many panels will be connected in series to create a high DC voltage, and then put into the inverter to convert DC current and voltage into AC power. 3 phase.

- A solar farm of 1MWp, consisting of 9 inverters with a capacity of 100KVA-121KVA will connect to a 1000KVA transformer to connect to the 22kv EVN grid.

- Solar power is built in places with good radiation sources, and used below to develop agriculture.

Author: Ngo Ngoc Bich