Design and energy analysis of 100% fresh air based hybrid liquid desiccant air conditioning system – A case study of a thermal power plant TG building

Abstract

Turbine generator (TG) buildings in thermal power plants require chilled water air conditioning systems (CWAS) to control the temperature and humidity of heat dissipated rooms, which are energy-intensive and non-eco-friendly. As an alternative, a novel refrigerant-free 100% fresh air (FA)-based hybrid liquid desiccant air conditioning system (HLDAS) is proposed and presented the methodology to design it for a case study of TG building of 2X660 MW power plant in the most humid climate. The cooling and heating requirements for HLDAS are met with a cooling tower and potential waste heat from the plant. To assess the saving potential of the proposed system, annual energy consumption for the HLDAS, 10% FA-based CWAS (CWAS-1) and 100% FA-based CWAS (CWAS-2) are quantified and compared. The results revealed that HLDAS consume 55% and 31% of CWAS-1 and CWAS-2 power consumption, respectively. Low-grade potential waste heat from the plant is estimated and found to be sufficient for solution regeneration. The proposed system is extremely energy efficient for 100% FA applications where low-grade waste heat is available. In addition to this, since there are no ODP gases associated with the proposed system, the proposed HLDAS is recommendable in view of environmentally friendly technology and indoor air quality (since it is a 100% FA-based system). This work will support HVAC engineers and researchers in designing the LDAS for a given air conditioning application.