AI data centers consume enormous amounts of electricity—not only to run thousands of GPUs, but also to keep them cool. A new study suggests that recovering waste heat while integrating on-site power generation and carbon capture could substantially reduce both their cost and carbon footprint.

Led by Professor Hankwon Lim of the Graduate School of Carbon Neutrality at UNIST, a research team evaluated a data-center energy system combining solid oxide fuel cells (SOFCs), carbon capture, and organic Rankine cycle (ORC) cooling. Compared with a conventional grid-powered, air-cooled system, the proposed approach could reduce total system costs by approximately 48% and lifecycle greenhouse gas emissions by up to 72%.

The system puts waste heat to work in two ways. High-temperature heat from the fuel cells supplies energy for the carbon-capture process, while heat removed from servers is recovered through an ORC to generate additional electricity. This reduces both the energy required for cooling and the amount of electricity the data center must draw from the grid.

The researchers modeled a data center with 20,000 GPUs and compared eight combinations of power supply, cooling, and carbon capture using energy prices and electricity mixes in Korea, the United States, and the European Union. Across a broad range of cost and emissions priorities, the combination of SOFC power, carbon capture, and ORC cooling consistently ranked highest.

ORC cooling performed particularly well across all three regions, reducing annual cooling-related electricity costs by as much as $19 million. Lower electricity demand also cuts annual greenhouse gas emissions by an estimated 80,000 to 150,000 metric tons, potentially avoiding $5 million to $10 million in annual carbon costs under carbon-pricing schemes such as the EU Emissions Trading System.

The preferred source of electricity varied by region. Relatively inexpensive natural gas made SOFC generation economically attractive in the United States, while in Korea, where natural gas is more expensive, grid electricity remained more economical when cost was prioritized.

“As AI data centers expand, electricity supply, cooling, and carbon emissions need to be considered together,” said Donghyoun Lee from the Graduate School of Carbon Neutrality at UNIST. “Our analysis shows how power generation, waste-heat recovery, and carbon capture can be evaluated as a single energy system.”

“The best strategy will depend on local energy prices and the carbon intensity of electricity,” said Professor Lim. “This framework can help identify energy systems that balance cost and emissions for data centers of different sizes and in different regions.”

The findings of this study have been published online in Chemical Engineering Journal on August 14, 2026. The research was supported by the National Research Foundation of Korea (NRF) and the Ministry of Science and ICT (MSIT).

Journal Reference

Donghyoun Lee, JeHyeon Seong, and Hankwon Lim, "An integrated solution for data center power supply, thermal management, and carbon capture evaluated through a multi-criteria decision analysis framework," Chem. Eng. J., (2026).