Development of a novel grid-free district cooling system considering blockchain-based demand response management

Abstract

District cooling system (DCS) enjoys improved cooling efficiency due to economies of scale cooling. However, most DCSs import electricity from the power grid, intensifying the electricity peak and grid investments. In addition, improving environmental sustainability is one of the major targets of DCSs. This study proposes a novel grid-free configuration to decouple the DCS from the power grid and natural gas networks. Meanwhile, an alternative operating strategy, waste cold energy recovery, ice storage, and cooling demand response are employed to promote the environmental sustainability of the DCS. Key results from this study have revealed that the proposed DCS does not need to import electricity from the power grid and facilitates a flexible plant location without the limitation of the natural gas network. Under the basic configuration, the daily primary energy saving rate (PESR) and energy cost saving rate (ECSR) can achieve 22.4% and 62.8%, respectively. The alternative operating strategy enhances the system’s part-load performance while the cold energy recovery unit facilitates extra cooling production. Further, the incorporation of the ice storage module improves the system’s average load rate and reduces the chillers' capacity. Finally, the blockchain-based decentralized network provides a trusted platform for implementing cooling demand response. Cooling demand response mitigates the cooling peak and total cooling consumption by precooling the space and adjusting the indoor set-point temperature in terms of the overall cooling load rate. Adopting these sustainable technologies yields the daily PESR and ECSR up to 35.2% and 68.9%, respectively.