Solar Power Trading Volume Drops Due to Monsoon and Typhoons... Increased Volatility in New and Renewable Energy

Longest rainy season in history and frequent typhoons
Frequent abnormal weather causes sharp decrease in sunlight hours
Stable power supply becomes difficult

[Asia Economy Reporter Moon Chaeseok] Due to the longest monsoon season in history and frequent typhoons, sunlight hours have sharply decreased, leading to a decline in solar energy power trading volume for three consecutive months. Since sunlight hours in August, when typhoons 'Bavi' and 'Maysak' struck, were halved compared to July, the usual pattern of 'increased trading volume in April-May → decrease in June-July → rebound in August' is unlikely to be repeated. This clearly reveals the fundamental vulnerability of new and renewable energy to supply instability caused by weather conditions. Concerns are rising that as unpredictable abnormal weather such as monsoons and typhoons due to climate change become more frequent, the intermittency of new and renewable energy could lower the stability of power supply.

According to the Korea Power Exchange's report on 'New and Renewable Energy Power Trading Volume (January 2015 ? July 2020)' released on the 8th, the provisional solar energy power trading volume last month was 370,055 MWh. After recording the highest trading volume ever at 571,155 MWh in April, it decreased for three consecutive months: 496,756 MWh in May, 489,060 MWh in June, and 370,055 MWh in July. Generally, solar energy trading volume is proportional to sunlight hours. According to the Korea Meteorological Administration, sunlight hours (based on Seoul) were 283 hours in April, then decreased to 177.9 hours in May, 206.1 hours in June, 119.4 hours in July, and 74.7 hours in August.

The problem is that abnormal weather has increased the volatility of new and renewable power production, expanding uncertainty. When production does not increase at times when it should, the predictability of power generation decreases, making stable power supply difficult.

Every year in August, when the monsoon season ends, solar energy power trading volume has rebounded compared to June and July, but this August, due to the impact of typhoons 'Bavi' and 'Maysak', sunlight hours sharply decreased, making it difficult for this pattern to reoccur. Looking at the solar energy trading volumes for July and August over the past five years: 137,720 MWh (July) → 151,267 MWh (August) in 2015; 165,980 MWh → 197,280 MWh in 2016; 187,602 MWh → 219,010 MWh in 2017; 315,522 MWh → 290,738 MWh in 2018; and 319,968 MWh → 374,271 MWh last year. Except for 2018, trading volume rebounded in August for four years.

Experts urge raising the reserve margin in the '9th Basic Plan for Electricity Supply and Demand' (9th Electricity Plan) considering the chronic intermittency problem of new and renewable energy. Since sunlight hours can decrease anytime due to abnormal weather, an 'insurance' to enhance the stability of new and renewable energy power supply must be prepared.

The working group, an advisory body for the government's 9th Electricity Plan, set the reserve margin at 22%, the same as the 8th Electricity Plan announced in 2017, in the draft released in May. To raise the share of new and renewable energy to over 20% in the 2030s while following government policies of 'nuclear phase-out and coal phase-out,' supply must be supplemented with liquefied natural gas (LNG) and other sources until intermittency-related supply instability is overcome. However, due to environmental issues such as fine dust, it is difficult to increase LNG power generation facilities, making it challenging to raise the reserve margin in the 9th Electricity Plan.

Professor Jeong Dongwook of the Department of Energy Systems Engineering at Chung-Ang University said, "Even considering that environmentalists might criticize oversupply of LNG facilities, it is puzzling that the reserve margin is maintained at 22%, the same as the 8th plan, while significantly increasing new and renewable energy. If sunlight hours sharply decrease depending on weather conditions in the future, power supply will have to rely on gas power generation, and maintaining the past reserve margin based on nuclear and coal power will inevitably increase power supply instability." An official from the Ministry of Trade, Industry and Energy said, "Even as the share of new and renewable energy expands, the reserve margin will be set based on a conservative scenario that can sufficiently prepare for this."

This content was produced with the assistance of AI translation services.