Hanh, the owner of a HCMC coffee shop in Go Vap District, said she had to close for half a day on May 18 because of a blackout.
"As soon as I opened the shop that day, the electricity went out. I couldn’t run fans or air conditioning, and it was too hot," she said. "Customers couldn’t sit in the cafe, so I had to temporarily close it."
Hoa, the owner of a boarding house in Hiep Phu Ward, HCMC's Thu Duc City, said her neighborhood suffered two power outages from the night of May 18 night to early in the morning the next day.
"It was very hot, so my tenants kept texting and calling. Asking the reason for the blackout and demanding that fix it," she said.
Other districts, including HCMC's Binh Thanh, Tan Binh and Thu Duc, have also had power cuts for many hours over the past few days.
A similar situation occurred in Hanoi. On May 18, the city recorded power outages in many areas.
Phan, a resident of Hai Ba Trung District, said his neighborhood blacked out twice, each time lasting 30-60 minutes.
In Bac Giang on May 18, the entire Song Khe - Noi Hoang Industrial Park and Van Trung Industrial Park experienced power outages.
Bac Giang Power Company said the two industrial parks consume some 3.6 million kWh of electricity per day and that if the power supply to them had not ceased, the entire residential area and other businesses in the province would have been affected.
The company said it was unknown when the electricity shortage would end because it depended on the weather.
Tran Viet Hoa, director of the Electricity Regulatory Authority of Vietnam, on May 18 cited data from national utility Vietnam Electricity (EVN), revealing that as of May 12, a total of 13 large hydropower reservoirs had been at or were approaching their dead storage capacity.
Most of the remaining hydropower reservoirs had water levels much lower than required, according to the data.
Earlier calculations by EVN showed that in the event of extreme situations the North would be at risk of a 1,600-4,900 MW electricity shortage this month and next.
However, electricity firms in Hanoi and HCMC have said that power cuts in the last few days were not related to supply.
According to Hanoi Power Corporation, a recent prolonged hot spell has cause a sharp uptick in electricity usage, especially at peak hours.
On May 17, electricity consumption in the capital city surpassed 85.3 million kWh, the highest level reached so far this year.
As a result, some electricity transmission lines and substations were overloaded or had problems, causing local interruptions of power supplies.
Bui Trung Kien, deputy general director of the HCMC Power Corporation, also said that sudden rises in electricity consumption this early summer led to some technical glitches, so the corporation had to cut power for a couple of hours to fix the issues.
Problematic transmission lines located underground take 5-6 hours to fix, he noted.
"We will ensure electricity supply for HCMC’s consumption and production needs, without rotating power cuts," Kien said.
Nguyen Phuoc Duc, general director of the Southern Power Corporation, said the electricity supply should be balanced and stable.
According to Duc, households increased electricity usage due to the hot weather, but many factories and production facilities narrowed their operations, so electricity consumption in industry has actually decreased.
Power corporations in Hanoi and HCMC are intensifying checkups on transmission lines and substations to replace or upgrade old ones.
On May 18, Prime Minister Pham Minh Chinh requested relevant ministries and sectors to ensure that there would be no shortage of electricity for production, business and consumption at least from now to May 25.
Mining and energy firms were urged to supply sufficient amounts of coal and oil and gas to thermal power plants.
EVN was tasked to make better use of hydroelectricity resources and further tap renewable power projects.
Earlier, experts had predicted that electricity shortages might occur in the peak months of hot weather, namely May, June and July.