Feasibility of a hybrid photovoltaic/thermal and liquid desiccant system for deep dehumidification

• Published in: Energy conversion and management 2018-05, Vol.163, p.457-467
• Main Authors: Su, Bosheng, Qu, Wanjun, Han, Wei, Jin, Hongguang
• Format: Article
• Language: English
• Subjects: Air conditioners; Air conditioning; Carbon; Clean Development Mechanism; Clean energy; Compression; Dehumidification; Desiccants; Driven force analysis; Drying agents; Economic analysis; Electric power; Electric power generation; Emissions; Energy conservation; Exergy; Feasibility; Feasibility studies; Humidity; Industrial applications; Investment; Liquid desiccant dehumidification; Photovoltaic cells; Photovoltaic/thermal collector; Photovoltaics; Power consumption; Power efficiency; Regeneration; Renewable energy; Sensitivity analysis; Simulation; Temperature; Two-stage dehumidification; Vapors
• ISSN: 0196-8904; 1879-2227
• DOI: 10.1016/j.enconman.2018.02.018

•A novel hybrid photovoltaic/thermal and liquid desiccant system is raised.•Moisture-removal ability of the desiccant solution is used in a cascade way.•Exergy destruction of the two-stage unit reduces concerning conventional one.•Dehumidification temperature has a decisive effect on the system performance.•Economic analysis shows the application value of the hybrid system. Air dehumidification is widely applied in the civilian and industrial use, however, conventional vapor compression air-conditioning system consumes substantial power. Using renewable energy in the air handling process has potential to further reduce the power consumption, meanwhile ease the carbon emission. This paper proposes a novel liquid desiccant system integrated with a concentrated photovoltaic/thermal collector for deep dehumidification. The generated electric power drives a vapor compression chiller for cooling the desiccant solution for a two-stage dehumidification, and the released heat from the collector is used for the desiccant regeneration. Simulation studies indicated the proposed system has a superior power saving ability of 55.65% comparing with the conventional one, besides the equivalent power generation efficiency reaches 8.7% in the base design condition. A comparative driven force analysis showed the two-stage dehumidification has a better match of driven force compared with the single-stage liquid desiccant dehumidification, thus leading to a reduced irreversible loss of 65.43%. Sensitivity analysis indicated that the dehumidification temperature has a decisive effect on the system performance. The exergy efficiency has a maximum value of 13% as the dehumidification temperature is 22.3 °C. The economic studies showed that the investment on the concentrated photovoltaic/thermal collector account for the largest share of the total initial investment, and has a significant effect on the payback period. The payback period would be reduced further if the benefit of the clean development mechanism (CDM) is considered.