Design and preliminary results of organic rankine cycle for liquid desiccant system

Abstract

In this study, the organic Rankine cycle (ORC)-based combined heat and power (CHP) system was developed and experimentally investigated to assess the feasibility of the application potential as an energy-efficient CHP system. This system harvests electrical energy from an unused district heat source and simultaneously provides heating for a liquid desiccant (LD)-assisted air-conditioning system. The working fluid selection is conducted considering its environmental impact under the operating conditions. When the maximum shaft power of ORC is 170.4 W under the tested condition, the thermal cycle efficiency is 4.5%. The ORC integrated with the LD (ORCLD) using Novec649 can provide a desiccant solution over 50 °C without an auxiliary heater and achieve the maximum overall CHP efficiency of 79.1%. Consequently, it is found that Novec649 is a suitable working fluid for the ORC when simultaneously harvesting the energy from the unused district heat and providing the hot water to the LD, and the current design of the ORC CHP system is well adapted to the district heating system and LD unit.