Performance Analysis of Solar Thermal Heat Pump for Hot Water Supply to Industrial Process

The thermal energy used in industrial processes is largely obtained from fossil fuels, causing global warming through carbon dioxide emissions. Worldwide efforts are underway to achieve decarbonization by using renewable energy sources to supply thermal energy. Solar energy, that offers infinite energy potential over a wide temperature range, and heat pumps, that provide a stable and an efficient heat supply, can synergize and capitalize on the advantages of each other. This study aimed to develop a solar thermal source heat pump (SSHP) to replace the existing 0.5 ton/h LPG steam boiler in food processing. Through a performance analysis, the heat supply ratio, solar fraction, and seasonal performance factor were derived based on the solar collector area and storage volume. The results indicated that the heat supply ratio of the SSHP was influenced more by the collector area than by the thermal storage volume. When the SSHP collector area was below a certain value, increasing the thermal storage volume reduced the SSHP heat supply ratio. Therefore, to operate the system stably and achieve a high performance index, the collector area must be larger. For the subject food process, a collector area larger than 210 m2 was required to achieve a seasonal performance factor exceeding 2.52, equivalent to power generation efficiency.