Effect of type of ground cover on the ground cooling potential for buildings in extreme desert climate

Developing hybrid cooling techniques to reduce domestic cooling demand is a key objective, but also poses a particular challenge in dry desert climates, such as that of Kuwait. Ground cooling, which is a passive cooling technique, could help meet this objective. In this study, the impact of different soil treatments on underground environment at 2.5m depth was investigated. The three soil treatments in this study were: dry ground (or bare soil) treatment, wet ground treatment and wet shaded treatment with grass ground surfaces in the underground environment. The tests were carried out at the three different locations over an entire year from the beginning of Jan. 2016 to the end of Dec. 2016. The findings revealed that the sub-soil temperature under wet shaded with grass surface is fluctuating less than that under dry ground surface. Sub-soil temperature curve under dry ground surface is showing temporal variations more emphatically than that for wet and wet with grass surfaces. These reductions were expected to be attributed to the variation of the above ground temperature due to vegetation which was carried out for the period from 12 to 26 August for comparison purposes. This comparison showed that vegetation above ground surfaces was found advantageous to reduce summer air temperatures by up to 7 Kelvin (K). To conclude, surfaces under wet and wet with grass ground cover can improve sub-soil cooling potential, creating advantageous soil surface boundary conditions. Furthermore, increase of sub-soil condition performance may be advantageous for sub-soil applications, such as underground buildings or earth cooling pipes, which will be investigated in the next phase in forthcoming research.