On March 03, 03, the Prime Minister issued Decree 2025/ND-CP detailing a number of articles of the Electricity Law on the development of renewable energy and new energy electricity. Decree 58 has regulated many specific issues and removed many obstacles that Decree 58/ND-CP issued in October 135 has not resolved.
Decree 58 and solutions to concerns
During many business trips to the southern provinces, GREEN IN experts have seen many shrimp farms consuming a large amount of electricity and having to pay tens of millions of VND for electricity each month. When asked why they did not install solar power to reduce the burden of electricity bills, shrimp farmers all gave the same answer that solar power is unstable and unreliable, especially for shrimp farms that have to aerate 24 hours a day.
If there is a problem with solar power, it will cause great damage to the health of shrimp and the property of farmers. In addition, farmers are concerned that installing solar power without clear regulations from the State on the mechanism can easily cause trouble in the future. Decree 58 has resolved these concerns of farmers.
Solar power is only generated during the day, with peak output at noon when solar radiation is at its highest. At this time, the national power system must also generate high output to meet electricity demand. Solar power systems help to share some of the burden on the national power system, saving fuel such as coal, gas or hydropower for when needed.
Economic and environmental benefits of rooftop solar
For households or businesses, the time from 9:30 to 11:30 is peak time, so the electricity consumption is also high. When installing rooftop solar power, the solar power system will take care of most of the electricity needs of households or businesses, significantly reducing monthly electricity bills.
My family in Hanoi also installed a 7,2kWp rooftop power system in 2019. It has been 6 years now, and the system has been operating completely stably, without significant damage, and only requires cleaning the panels about once every 1 to 2 months. In the summer, when there is a lot of sun, the family's electrical appliances that use a lot of electricity, such as air conditioners, use most of their electricity during the day from solar power. The monthly electricity bill is only half of what it was before installing solar power.
When the solar power system is connected to the grid, electricity from the solar power system is given priority to be used first. If there is a shortage, the system automatically takes the shortage from the grid to supplement it. When the solar power generated is too much but not used up, the system will automatically pump the excess electricity into the grid. The system works completely automatically without any human intervention.
According to our calculations, the current price of solar power in the Southern region is about 1.000 VND/kWh to 1.200 VND/kWh, cheaper than the price of household electricity by about 800 VND/kWh to 1.000 VND/kWh. Thus, if households use electricity at the price of household electricity, for each kWh or some amount of electricity saved, the household will save an average of 900 VND. For households using electricity at the price of business electricity, the benefits are even greater, from 1.500 VND/kWh to 2.000 VND/kWh.
We installed a 30kWp solar power system at a milk processing factory in Ba Vi, Hanoi. This solar power system is equipped with a zero export inverter that allows to take electricity from the grid but not pump excess electricity back to the grid.
GREEN IN handed over the solar power system at Ba Vi Milk Production Joint Stock Company
Before installation, the factory had to pay from 80 million to 100 million VND per month for electricity. After installation, the family's electricity bill was reduced by two-thirds, about 55 million to 65 million VND per month, saving about one-third of the monthly electricity bill.
Decree 58 also allows grid-connected solar power systems to sell 20 percent of their electricity to the national grid. It should also be noted that rooftop solar power is a form of self-produced, self-consumed solar power, installed primarily for on-site use and not for commercial purposes. So how much capacity is reasonable for each household or enterprise to install?
When the capacity of the rooftop solar power system is installed at the same capacity as the load capacity of the household or enterprise, the solar power output will be used nearly 100 percent. At the milk processing factory in Ba Vi mentioned above, the factory's solar power is consumed 99 percent, with only about 1 percent lost during the lunch break from 12:1 to XNUMX:XNUMX p.m. due to the use of a zero export inverter. If an on-grid inverter is installed, it is entirely possible to sell this excess electricity to the grid.
For households or businesses that need to know exactly how much capacity to install, expert help is needed.
For households in areas without a national grid, installing solar power with battery storage is the most feasible solution both technically and economically. We have supported people in Tinh Bien and Tri Ton districts, An Giang with thousands of small-scale solar power systems with battery storage. These solar power systems have improved the living conditions of thousands of households in this area.
Sustainable Development Expectations and International Commitments
In addition to financial benefits, rooftop solar power applications also help reduce greenhouse gas emissions and environmental pollution. To produce 1kWh of electricity, the Vietnamese power system emits about 0,66kg of CO2, a greenhouse gas that causes climate change and emits fine dust PM and toxic gases such as NOx, SO2, etc. When using each kWh of solar power, households or businesses will reduce 1kWh of electricity from the grid, which means reducing 0,66kg of CO2 and corresponding toxic gases. According to estimates at the milk processing factory in Ba Vi mentioned above, 20 tons of CO2 can be reduced into the atmosphere each year.
At COP26 in the UK, Prime Minister Pham Minh Chinh pledged that Vietnam would achieve net zero emissions by 0. Rooftop solar power application is a small but important contribution in fulfilling Vietnam's promise to the international community.
Decree 58 has opened a path for the development of rooftop solar power. Hopefully, rooftop solar power will develop strongly in the coming time, playing its proper role in the development of Vietnam.