Energy performance and energy conservation technologies for high-tech cleanrooms: State of the art and future perspectives

Over the past few years, numerous countries have rapidly expanded the number and size of their high-tech clean fabrications, to keep pace with electronic devices and Internet needs. Moreover, extremely strict dry-bulb temperature, relative humidity, and particle concentration requirements cause high-tech cleanrooms to consume enormous energy, which is nearly three times the average energy consumed by data centers. Reducing energy use while ensuring the required built environment for normal production has become key challenges in high-tech clean manufacturing, and gradually attracted public and academic attention. However, different from extensive research and review studies conducted on data centers, no study has systematically reviewed state-of-the-art research on the energy aspects of high-tech cleanrooms. Therefore, this paper comprehensively reviews the research work on energy performance and energy conservation methods for high-tech cleanrooms. The main features and energy use status of high-tech cleanrooms are presented and analyzed. The energy models and evaluation metrics of high-tech cleanrooms, as well as the performance assessments and analysis of their environmental control systems (i.e., air-conditioning systems) are summarized and elaborated. Efforts on the performance improvement and energy conservation of high-tech cleanrooms, particularly air-conditioning systems, are also reviewed from multiple aspects, i.e., cold-heat offset reduction, air exchange rate, and airflow resistance optimization, and cooling plant efficiency improvement. A future framework for establishing smart, sustainable, and efficient high-tech cleanrooms is also proposed and discussed.