Optimization of CO2 heat pump system for simultaneous heating and cooling applications.

Many commercial buildings, including data centers, hotels, and hospitals, have a simultaneous heating and cooling demands depending on season, occupation, and auxiliary equipment. In data centers, electrical equipment produces heat, which must be removed to prevent the equipment temperature from rising to a certain level. With proper integration, this heat could be used as a cost-effective energy source for heating the buildings. Liquid-to-liquid carbon dioxide (CO2) heat pump systems are a promising technology for such applications. A data center on the Purdue University West Lafayette campus is modelled and analysed. A heat pump system with appropriate thermal storage is suggested for the data center application. The proposed heat pump system is compared to the existing conventional system for a 12-months period, which results into annual energy savings of 28%. This system also shows noteworthy fuel savings and reduction in the CO2 emissions.