Study of The Energy, Economic, Environmental, and Thermal Comfort Impact of The Integration of Hemp Concrete and Hemp Plaster in a Residential Building Envelope in Morocco

Abstract

In the building sector, the majority of efforts are aimed at achieving greater energy efficiency, a low carbon footprint, and optimum thermal comfort to make buildings more efficient, more sustainable, and more pleasant to live in. In this context, this paper aims to assess the impact of integrating environmentally friendly and green materials (lime-hemp plaster and hemp concrete) into the envelope of an existing residential building. A numerical simulation study was carried out using TRNSYS 18, in four Moroccan climates: Mediterranean, cold semi-arid, hot semi-arid, and hot and dry desert, to study the energy, economic, and environmental impact, as well as that of the thermal comfort. The proposed construction scenarios are compared with the reference scenario in terms of heating and cooling requirements, electricity bills, carbon footprint, and percentage of annual thermal discomfort. The results show that energy savings are highest in the cold semi-arid climate (Oujda) at around 24%. Hemp concrete construction is more effective in reducing heating requirements, with a reduction of up to 39.4%. For cooling, the reduction is only 15.5%. The economic and environmental study shows that using materials such as hemp concrete in an optimal construction and climatic context can reduce electricity bills by 25% and CO2 emissions by around 23.7%. However, the reduction in terms of hours of discomfort is not yet significant enough. Hence the need to combine this technique with other strategies based on bioclimatic design. The use of hemp plaster and concrete for renovating existing buildings or constructing new ones represents a very promising alternative from several points of view: energy, economic, and environmental.