Comparison of Liquid-Desiccant-Assisted Air Conditioning and Dedicated Outdoor Air Systems

Researchers from Hanyang University assessed and compared the energy performance of two different novel air conditioning systems

Increasing heating and air conditioning energy consumption leads to high energy consumption in the building sector. According to China Association of Building Energy Efficiency: The Overall Situation of China’s Building Energy Consumption, 2019, in China, the energy consumed in the building sector accounts for around 30% of the national energy consumption. Among the several energy-conserving heating, ventilation, and air-conditioning (HVAC) systems, two novel applications: dedicated outdoor air system (DOAS) and the liquid-desiccant and indirect-direct evaporative-cooling-assisted air conditioning system (LD-IDECOAS) offer desirable energy-saving and indoor environmental quality enhancement potentials compared with conventional variable air volume systems.

Now, a team of researchers from Hanyang University conducted a series of detailed energy simulations to compare and analyze the energy performance of DOAS and LD-IDECOAS. HPLD-IDECOAS—Heat-pump-integrated liquid-desiccant and evaporative-cooling-assisted system uses 100% outdoor air. The team found that the HPLD-IDECOAS has higher energy-saving potential in warmer regions compared to the DOAS. The difference in annual energy consumption between the two systems is small at 18% in dry regions with high altitudes.

The major energy consumption of the DOAS is the use of the dehumidification part of the chiller and reheat coil, whereas the main energy consumption of the HPLD-IDECOAS is the heat-pump-integrated liquid-desiccant system. The HPLD-IDECOAS has more energy-saving potential in the selected cities compared to DOAS, owing to use of an HP instead of a chiller. HPLD-IDECOAS has more annual energy-saving potential compared with the DOAS. The annual energy consumption of the HPLD-IDECOAS saves a total of 51% compared to the DOAS. Increase in humidity, increased the energy-saving potential of the HPLD-IDECOAS compared to that of the DOAS. The research was published in the journal MDPI Energies on May 11, 2019.

You May Also Like