Power supply and renewable energy
"Battery energy storage systems (BESS) and the power conversion technology that controls them will become key competitive capabilities for addressing renewable energy intermittency and responding to rapid changes in electricity demand."
Kim Seong-yeop, chief of OCI Power, made the remarks on October 30 at the AI Gold Rush conference of Smart Energy Plus (SEP) 2026, held in Hall B at COEX in Samseong-dong, Gangnam, Seoul. Presenting on "The Importance of Renewable Energy and Battery Energy Storage Systems (BESS) in AI Data Centers," Kim identified stable electricity supply and energy storage technology as factors determining AI data center competitiveness.
Kim said securing renewable energy was emerging as a key competitive factor in the AI data center market. "Global companies such as Microsoft and Google are moving beyond RE100, or 100% renewable energy, toward the concept of carbon-free energy, which supplies electricity from energy sources without carbon emissions," Kim said. "In the future, major AI data center customers will place importance on whether they can receive electricity through renewable energy and power purchase agreements (PPAs)."
Renewable energy intermittency and fluctuations in AI data center electricity demand are challenges that need to be addressed. Renewable generation varies with weather and natural conditions. Solar generation is concentrated during daylight hours, while wind generation varies substantially with wind conditions. Alongside supply variations, AI data centers also experience large fluctuations in electricity demand. Servers based on accelerators such as GPUs and NPUs repeatedly perform large-scale computation and communication, causing power consumption to change rapidly on a millisecond timescale, with a millisecond equal to one-thousandth of a second.
Kim explained, "AI data centers consume power intensively when computation begins, but electricity consumption drops sharply when they enter the communication phase. Repeated fluctuations of this kind can affect voltage and frequency and undermine grid stability."
Battery storage and hybrid systems
Kim proposed BESS as an option for addressing these problems. "When a data center has been built but cannot begin providing services because electricity supply is delayed, using BESS could help reduce the burden associated with the time needed to build power infrastructure," Kim said. "It is also possible to store electricity when renewable generation is high and supply it to data centers when needed."
Kim also noted that conventional batteries alone may have limitations in responding to rapid changes in AI data center electricity demand. The alternative Kim proposed was a hybrid ESS combining ultracapacitors, or supercapacitors, with lithium iron phosphate (LFP) batteries. Unlike batteries, which store energy through chemical reactions, capacitors use an electric field. Although their energy storage capacity is relatively low, they can charge and discharge power rapidly.
Kim said, "Data center power loads change on a millisecond timescale, but conventional BESS have limitations in charging and discharging speed. A hybrid approach combining supercapacitors and LFP batteries could help respond to rapid power fluctuations."
Power conversion and grid-forming technology
Kim also emphasized the importance of power conversion system (PCS) technology. The explanation was that technology for reliably supplying stored electricity to the actual grid and data centers matters alongside battery performance. In particular, Kim expected grid-forming technology, which independently regulates grid voltage and frequency without relying on an external power grid, to emerge as a key technology.
Kim emphasized, "Batteries can be sourced anywhere, but the power conversion system connected to the battery performs the system's control functions. Ultimately, it is important to secure not only battery technology but also power conversion systems and grid configuration technology."
Original Korean article: Money Today
English brief by Korea Wind Intelligence, koreawindintel.com
