Hydrogen refueling station synergistically driven by liquid hydrogen pump and thermal compression

Abstract

The energy consumption of conventional 70-MPa hydrogen refueling stations (HRS) with liquid hydrogen (LH2) pumps remains at a high level due to the low efficiency of LH2 pumps working at extremely high pressures, up to nearly 90 MPa. This paper presents a novel HRS with significantly lower energy consumption, based on a step-by-step compression strategy enabled by a highly-efficient 50-MPa LH2 pump for low-pressure compression and a subsequent thermal compression module for high-pressure compression driven by thermal energy. The performance of the cryogenic pressure vessels in the HRS process is analyzed via a numerical model, and then several improvements to the HRS process are proposed for large-scale refueling requirements. Finally, the techno-economic performance of the HRS is compared with the conventional HRSs and the HRS with pure thermal compression. Compared to the conventional HRSs with 90-MPa LH2 pumps, the capital cost of the proposed 400-kg/day HRS is reduced to $1.52M from $1.80M, while its energy consumption is reduced to 0.3 kWh/kgH2 from 1.3 kWh/kgH2. This work provides a new solution for low-energy-consumption hydrogen refueling which would be beneficial for reducing the overall cost of the hydrogen supply chain.