Not the only answer

In 2011, the first inland wind power generator was installed in Pohang, North Gyeongsang. But it caused trouble as it broke down every one or two years. Repair took four months because the generator, imported from Denmark, had to..

SOHN HAE-YONG The author is the head of economy policy teamof the JoongAng Ilbo.

In 2011, the first inland wind power generator was installed in Pohang, North Gyeongsang. But it caused trouble as it broke down every one or two years. Repair took four months because the generator, imported from Denmark, had to be fixed by Danish engineers. North Gyeongsang demolished it at the end of 2016, as it was wasting taxpayers’ money. The world’s first rotating solar energy system installed in a reservoir in Anseong, Gyeonggi, has solar panel modules that rotate like a sunflower and take in more sunlight. But when the reservoir dried out due to a drought in 2017, it stopped rotating and electricity production was disrupted.

In the Moon Jae-in administration’s nuclear phase-out efforts, solar and wind power are leading the expansion of renewable energy. But there are unexpected factors in maintenance and operation. The biggest weaknesses are the weather and climate change. Joo Han-gyu, a professor of nuclear engineering at Seoul National University, said that solar energy cannot be generated at night or on cloudy days. Wind energy cannot provide stable electricity because the amount of wind that fluctuates.

According to a report that People Power Party (PPP) lawmaker Yoon Young-seok received from the Electricity Exchange, solar energy only made up 0.4 percent of the total energy generation at the peak demand time between Jan. 1 and 14. Yoon explained that heavy snow from Jan. 6 piled up on the solar panels, and dropping temperatures lowered the power generation efficiency. In July last year, solar energy made up 0.8 percent of the total at its peak times, and 1.8 percent in August. That was when Korea recorded one of its longest rainy seasons in history. Wind energy didn’t help much during this time — accounting for only 0.2 to 0.5 percent at peak times.

Recklessly expanding solar and wind energy without taking their limits into account could damage the stability of electricity supply. The blackout in Texas last month is an example. The crisis grew after wind energy and solar energy — which made up a big portion — stopped in severe cold and heavy snow. The Wall Street Journal pointed out that wind and solar energy cannot generate electricity 24/7, but the belief in renewable energy was too big.

Renewable energy needs to be increased in the long run. But it is a multi-variable equation involving many factors, including changes in electricity infrastructure and expansion of energy storage system. Approaching the issue by treating nuclear and coal-powered generation — which supplied nearly half (46.3 percent) of the electricity supply last year — as “absolute evil” and new renewable energy as “absolute good” cannot produce an effective solution.