Paper Conference

Proceedings of BSO Conference 2016: Third Conference of IBPSA-England


Pdec Tower Cooling Energy Performance Assessment Using Specific Enthalpy Calculation Methodology

John P Brittle, Mahroo M Eftekhari & Steven K Firth

Abstract: Passive downdraught evaporative cooling (PDEC) is a method of passively cooling an internal space using water micronisation i.e. introducing moisture into ventilation supply air streams. To date, PDEC design tools are very limited and varying relative humidity limits are not fully considered. This paper presents a design methodology using specific enthalpy calculations. A theoretical commercial building case study is developed (base case) using dynamic thermal simulation (DTS). Climate locations are hot climates (Lisbon, Portugal and Nairobi, Kenya) to compare differences in cooling potentials. Calculated values show that humidity levels at 50% have a greater rate of cooling capacity compared with lower RH values. Calculated annual mechanical cooling energy reductions while incorporating PDEC Tower are: • 12% (30% RH), 14% (40%RH) and 16% (50% RH) for Portugal. • 7% (30% RH), 8% (40% RH) and 9% (50% RH) for Kenya. This methodology is effective for calculating minimum PDEC cooling available in these climates. This method can be used for RIBA stage 2 analyses (concept design) and enable assessment PDEC system payback.
Pages: 211 - 218