[Edaily Reporter Kim Hyung-wook ] During the National Fiscal Strategy Meeting on the 13th, President Lee Jae-myung remarked that electricity rates for general households should be set lower during off-peak hours when power is abundant and higher during peak hours when demand is high, bringing the discussion on introducing seasonal and time-of-use rate plans for residential customers to the forefront.

The government has not yet announced a specific plan regarding when or how this will be implemented. Realistically, it is likely to take a considerable amount of time before full implementation. However, as the share of renewable energy—particularly solar power, which is mainly generated during the day—is rapidly increasing, the need to encourage the shifting of electricity usage to daytime hours, when generation is high, through differential pricing continues to grow. Such differential pricing is already in place for other categories of electricity, such as industrial and general-purpose rates.

◇Using Multiple Appliances at Once After Work Could Dramatically Increase Your Bill

Assuming the government applies the new industrial time-of-use rate system—which took effect on April 16—to ordinary households as well, electricity bills could rise significantly if we do not change our daily habits.

Currently, electricity rates for residential households remain the same regardless of when it is used. For a four-person household, summer electricity consumption is about 400 kilowatt-hours (kWh); the bill structure consists of a base fee plus an additional 150 won per kWh, totaling 60,000 to 70,000 won per month. Although a progressive rate system is applied—where the unit price can increase up to 2.6 times depending on total monthly consumption—this system does not distinguish between seasons or times of day.

However, if seasonal and time-of-use rate plans—similar to those for industrial customers—were applied to residential customers, the difference in rates depending on the time of day could be as much as double. For industrial electricity rates during the summer (June–August), the average electricity charge is approximately 170 won; however, the rate during off-peak hours—from 10:00 p.m. to 8:00 a.m. on weekdays—is 116 won, whereas the rate during peak hours—from 3:00 p.m. to 9:00 p.m. on weekdays—reaches up to 229 won. This structure means that even for the same amount of electricity, the rate can vary by up to twofold depending on the time of day.

For example, turning on the air conditioner after work and running the washer and dryer before 9:00 p.m., then preparing dinner using an induction cooktop, air fryer, and dishwasher could be considered a luxury—using electricity during the most expensive time slot. When using a washing machine, dryer, dishwasher, and air conditioner (based on one hour of operation) simultaneously, the power consumption is approximately 4–5 kWh. Calculations show that while this would cost 500 won if used in the early morning or morning, it could cost 1,000 won in the evening. If this pattern is repeated 20 times a month, the difference in the monthly bill could reach 10,000 won.

Of course, there are also ways to reduce the burden of electricity bills. You can lower your bills by shifting the use of high-power appliances to off-peak hours—such as late at night, early morning, or the early hours of the morning—or by taking advantage of mid-day medium-load hours. Since many modern appliances have a scheduling function, utilizing this feature is another effective strategy.

◇Unlikely to be implemented immediately…but it will become a reality someday

Electricity authorities have long been exploring the possibility of introducing seasonal and time-of-use rate plans for residential customers. A prime example is the pilot program that has been in effect since 2021 on Jeju Island, which is rich in renewable energy. On Jeju, households can choose between a flat-rate plan or a time-of-use rate plan. Households that opt for the time-of-use rate plan are subject to rates that vary by up to 1.6 times depending on the time of day, based on summer and winter seasons.

It is unlikely that this system will be rolled out nationwide in the short term. If operated on an opt-in basis like in Jeju, only households whose existing usage patterns would benefit from it might sign up, potentially limiting the overall demand-shifting effect. Conversely, if the plan were mandated for all households or if the difference in time-of-use rates were set too high, it could spark controversy over skyrocketing bills—particularly among dual-income and childcare households—and lead to public backlash. Another reason there is no immediate need to expand this to residential customers is that applying time-of-use rates to industrial and certain general-use sectors—which account for more than half of the nation’s total electricity consumption—can already achieve a certain degree of demand shifting.

Furthermore, the infrastructure required for full-scale implementation of the system is still inadequate. Currently, installing Advanced Metering Infrastructure (AMI) is necessary to track each household’s electricity usage by time of day; while these meters are installed in most single-family homes, the adoption rate per household in apartment complexes remains in the 10% range.

However, discussions on its introduction are expected to continue. Given the rapid expansion of renewable energy deployment, it is highly likely that the system’s introduction will become inevitable within the next few years. Following the introduction of the new time-of-use rate plan for industrial and general-use customers in the first half of this year, authorities are exploring ways to extend its application to residential customers starting in the second half of the year.

#KoreaElectricPower Corporation (KEPCO) also introduced a new energy cashback program, limited to July and August of this year, that provides 500 won per kWh—up to a maximum of 10,000 won per month—in cash to households that reduce their electricity consumption on weekdays between 5:00 p.m. and 8:00 p.m. Since the introduction of a new system that increases the cost burden would be a significant burden, the government has initially opted to encourage time-of-use adjustments through “incentives.”

An official from the Ministry of Climate, Energy, and Environment stated, “We will continue to foster a culture where consumers flexibly adjust their electricity usage based on economic incentives to promote national-level energy efficiency.”