78 Performance Assessment of a Novel Dew Point Air Conditioning System in the UK Climate Conditions

This paper investigated the feasibility of a novel dew point evaporative cooling for air conditioning of buildings in the UK regions. The issues involved analyses of the UK weather conditions, investigation of availability of water for dew point cooling, and assessment of cooling capacity of the system over various regions of UK. It is concluded that the dew point system is suitable for most regions of the UK, particularly the regions around Finningley and Aberdeen where the climate is drier than other regions in summer. Lower humidity results in higher difference between the dry bulb and dew point of the air, which benefits to the system in terms of enhancing its cooling performance. Tap water has a suitable temperature to feed the system for cooling and its consumption rate is in the range of 2.1 to 2.4 litre∕kWh output. The cooling output of the system ranges from 3.1 to 4.2 W per m³∕h air flow rate in the UK depending on the region where the system applies. For a unit with 2kW of cooling output, the required air volume flow rate varies with its application location and is in the 500 to 570 m³∕h range. For a 100 m² of buildings with 30W∕m² cooling load, if the system operates at working hours, i.e., 9:00am to 5:00 pm, its daily water consumption would be in the range of 60 to 70 litres. Compared with mild or humid climates, the dry and hot climates need less air volume flow rate and less water.