Sharing the same fate as solar power, sales of wind power in Vietnam are expected to be difficult because of "severe excess electricity" at some point in time.
The Electricity of Vietnam (EVN) Group has submitted to the Ministry of Industry and Trade a report on the situation of the power market.
So far, EVN has signed power purchasing contracts with 113 wind power projects with a total capacity of 6,038MW.
The number of projects put into commercial operation is 12, with a total capacity of 582MW.
The number of projects that will be put into commercial operation before October 31, 2021 is 87, with a total capacity of 4,432 MW.
The number that may not be commercially operating before December 31, 2021 is 14, with a total capacity of 1,024 MW.
In general, during the flood season and late months of 2021, excess electricity will appear when renewable energy sources account for a large proportion, especially on holidays and Tet (lunar New Year). From October to December, when wind power sources are in full operation, simultaneously with the flood season in the Central – Southern region, the excess capacity may be higher for a longer period.
From July to September 2021, the main flood period in the North will occur, which will facilitate hydropower generation. The northern power system will be balanced while power transmission between the North - Central region will be at a low level. This exacerbates the risk of system-wide overcapacity. Renewable energy cuts can be as high as 3000/6,500MW during the midday of weekday or weekend. Estimated cut for renewable energy output per month is more than 180 million kWh.
In the period of October-December 2021 - the main flood season in the Central and Southern region - as hydroelectricity is highly exploited, the reduction in renewable energy due to overloaded transmission and excess power supply on the system on weekdays or Sunday can reach 6,800MW/10,800MW. Estimated cut for renewable energy output per month is 350-400 million kWh.
"If renewable energy projects are put into operation earlier than scheduled or hydropower plants discharge simultaneously, the amount of renewable energy that will be cut may be even higher," noted EVN.
Many wind power projects are being developed at a time when the transmission line has become overloaded. As a result, there could be difficulty selling power.