[Report] "Edison Was Right" From AC Back to DC, Power Industry Faces Major Shift

Gwangju 'Bigspo 2024' Preview
Unpack Showcases New Energy Technologies

On the 6th, at the DC Experience Hall within 'Bigspo 2024' held at the Kim Dae-jung Convention Center in Gwangju, an official is explaining the current war between Thomas Edison and Nikola Tesla. Photo by Kang Hee-jong.

At the DC (Direct Current) experience center set up inside the exhibition hall of 'BIXPO 2024,' which opened on the 6th at the Kim Dae-jung Convention Center in Gwangju, characters of Thomas Edison and Nikola Tesla stood side by side to greet visitors. This was to explain the Current War between Edison and Tesla in the late 1880s. The technological competition between the two ended with Tesla's victory when the alternating current generator, advantageous for long-distance transmission, was chosen at the 1893 Chicago World's Fair. Since then, for over 130 years, the AC system has been established as the standard for electricity.

However, now we are facing a major transition back to direct current. Recent technological advances have made it possible to transmit power over long distances even with DC. Moreover, DC offers excellent power efficiency, significantly reducing electricity bills, and does not generate harmful electromagnetic waves to the human body. Since renewable energy sources such as solar power, wind power, and fuel cells also produce DC, the connectivity with future energy sources is excellent. For home appliances, there is no need to equip parts that convert AC to DC, which reduces costs.

At the opening ceremony of BIXPO 2024 on the 6th, Kim Dong-chul, CEO of Korea Electric Power Corporation (KEPCO), declared a 'DC Vision' for expanding future power grids and advancing the domestic power industry overseas. CEO Kim emphasized, "As a result of the DC distribution network independent island demonstration project on Seogeochado Island in Jeollanam-do, we confirmed that energy efficiency improved by more than 10% compared to the existing AC system. If we can lead this trend of changing the power system standard from AC to DC, we will secure competitiveness in the global energy market, improve the quality of life for our citizens, and gain opportunities for new job creation."

KEPCO plans to expand DC infrastructure supply, lead technological innovation and standardization, and develop supply policies and market creation activities such as DC tariff systems. On the 7th, with about 100 related organizations attending, the 'K-DC Alliance' was launched to demonstrate the will to become a global leader in the DC field.

A smart home appliance system using direct current power exhibited at the DC Experience Center within 'Bigspo 2024,' which opened on the 6th at the Kim Dae-jung Convention Center in Gwangju. Photo by Kang Hee-jong

According to the Korea Electronics Technology Institute (KETI), switching from AC to DC could save about 6 trillion won annually in electricity bills for six major home appliances. Korea Electric Power Corporation could save 1 trillion won. Nationally, this would generate an economic benefit of 7 trillion won.

However, converting the national power system requires a long time and significant costs. "The cost required for switching to DC is estimated at about 30 trillion won, excluding construction costs," and "just as it took 40 years to switch from 110 volts (9V) to 220V in the past, a long time will be needed," it was explained.

On the 7th, a KEPCO official explained the medium-voltage direct current transmission (MVDC) equipment under demonstration at the KEPCO Energy New Technology Research Institute in Naju, Jeonnam. Photo by Kang Hee-jong

Currently, South Korea has commercialized high-voltage direct current transmission (HVDC) in some sections and is in the early stages of commercializing low-voltage direct current transmission (LVDC). Medium-voltage direct current transmission (MVDC) is currently at the demonstration stage. A KEPCO Energy New Technology Research Institute official conducting MVDC demonstrations explained, "We are conducting pilot projects installing MVDC in areas rich in renewable energy such as Sinan-gun and the Naroho launch complex."

The biggest attraction of BIXPO 2024 was the newly introduced Unpack event this year. Kim Bu-gi, CEO of Standard Energy, showcased the 'Energy Tile' using vanadium-ion batteries (VIB) for the first time at the Unpack event. Vanadium-ion batteries use water-based electrolytes, making them safe from fire hazards.

On the 6th, at the 'Bigspo 2024' unpack event held at the Kim Dae-jung Convention Center in Gwangju, Kim Bu-gi, CEO of Standard Energy, is presenting about energy tiles. Photo by Kang Hee-jong

The energy tile introduced that day was designed by shaping vanadium-ion batteries into tile forms so they can be attached indoors. It is an indoor energy storage system (ESS). Until now, ESSs were mainly installed outdoors due to fire risks. Vanadium-ion batteries have no risk of ignition, allowing indoor installation. Standard Energy also demonstrated that even when an energy tile was drilled through, it did not ignite and maintained its performance.

Park Jung-seok, CEO of Korea Mobility, introduced a hubless bicycle. The hubless bicycle is an electric bicycle that uses motor technology to rotate the rim without using hubs or spokes. This technology can be applied in various fields such as scooters, motorcycles, and electric wheelchairs. Because it has no hub structure, an electronic paper display (EPD) can be installed inside the wheel to be used as an advertising medium. Famous European football clubs such as Real Madrid and Paris Saint-Germain are already using this as an advertising tool. CEO Park said, "We are also developing a 'No-No Bike' that does not require charging."

At the Bigspo 2024 Unpack event held on the 6th at the Gwangju Kim Dae-jung Convention Center, Park Jung-seok, CEO of Korea Mobility, is presenting the hubless bicycle. Photo by Kang Hee-jong

Woo Seong-hoon, CEO of Amoji, showcased a power pack, an ammonia-based hydrogen fuel cell. Amoji is an integrated system that cracks ammonia into hydrogen and immediately produces electricity from a hydrogen fuel cell. It is already conducting demonstration experiments in the U.S. on drones, tractors, large trucks (300kW class), and currently on ships (1000kW class).

Woosung Hoon, CEO of Amoji, is introducing an ammonia-based hydrogen fuel cell product at the 'Big Expo 2024' unpack event held on the 6th at the Kim Dae-jung Convention Center in Gwangju. Photo by Korea Electric Power Corporation

Amoji, headquartered in the U.S., was founded by four Massachusetts Institute of Technology (MIT) alumni and is based in Brooklyn. It is a unicorn company that has received investments from Aramco, Korea Zinc, and SK Innovation. CEO Woo said, "Ammonia will be an important energy source for decarbonizing heavy industries. We are currently building mass production facilities and expect to commercialize fully from 2025."

Other exhibits at the Unpack event included Poneithers' air purification and carbon reduction solutions using microalgae, HD Hyundai Electric's world-first 1-megawatt (MW) class DC distribution system, LS Electric's eco-friendly superconducting power system, and LS Cable's subsea cables for floating offshore wind power.