Energy–Carbon Synergy in Data Center-Based Energy Hub: Optimal Trading Decision in Coupled Electricity–Heat Markets Under Ladder-Type Carbon Trading

Data centers are becoming flexible prosumers in integrated electricity–heat systems (IEHSs) because of their large energy demand, workload flexibility, and waste-heat recovery potential. Coordinating these resources can improve energy utilization and carbon performance while supporting sustainable operation without curtailing computing services. This paper develops a trading decision-making approach for a data center-based energy hub (DCEH) participating in coupled electricity, heat, and carbon markets while accounting for independently operated power and district heating networks. The DCEH strategically bids electricity and heat prices and quantities and acts as a price taker in a ladder-type carbon market. A detailed DCEH model coordinates workload shifting, server operating states, thermal dynamics, waste-heat recovery, combined heat and power, a gas turbine, and energy storage. A bilevel model is then formulated in which the DCEH optimizes its bids and operation at the upper level, while the lower level clears the electricity and heat markets subject to network constraints. The bilevel problem is reformulated as a single-level mixed-integer linear program using KKT conditions, big-M linearization, and binary expansion. Case studies on a PDN33-DCEH-DHN32 system show that coupled energy–carbon trading improves the DCEH’s private financial outcome and reduces emissions, although the carbon-aware strategy does not necessarily minimize total physical system resource cost. Flexible DCEH operation further reduces the DCEH cost and emissions across different carbon mechanisms and grid-price scenarios, supporting more sustainable DCEH operation.