Energy Efficiency and Insulation Thickness According to the Compactness Index Case of a Studio Apartment Under Saharan Weather Conditions

Abstract

Financial energetic problems oblige citizens to reduce the energy consumption. Accordingly, the recent research showed that major financial economies can be optimally achieved, by introducing some passive measures. The main objective of the current contribution is to investigate the impact of thermal insulation and compactness on energy efficiency. Following the assessment of the methodology, several input parameters were identified and economic insulation thicknesses were obtained. Finding revealed that the best effectiveness of solar gain has been observed for a better insulation and a good compactness, whereas a reduction of about 12.51% of energy needs can be achieved. Similar to the previous case, compactness has an attractive effect, provided that the building was well insulated. Furthermore, any variance cannot be occurred in economic insulation thickness by varying the building compactness. Unlike this remark, for a better compactness, a slight increase in the investment-return time has been noticed, following the energy bill reduction, which becomes more interesting. Hence, the comparative study averred that the previous passive concepts provide reduction in energy needs nearest 73.64%. Thus, reduction was nexus 82.17%, during cold season, and around 59.87%, in overheating period. As consequence, the studied structure type can be integrated in the buildings that have an energy label of “type C.”

Efficient Energy and Financial Solutions for Residential Buildings in Algerian Saharan Climate

“…The energy balance has to deal with the physical parameters, thermal properties, building design, climatic conditions…etc. In the heating season and during interseasons, consumption and heating energy needs for buildings are given by the following formula [20][21]:…”

“…Heating or/and cooling needs due to the building thermal envelope are defined by equation 3 [20][21]:…”

“…In any event, it is considered that the required volume of the hot water is 50 litters of hot water at 50°C per day per person. Energy needs for the DHW production is given by the following equation [20][21]:…”

“…The human being diffuses radiations in sensible (by the body at 37 °C) and latent (by the production of water vapor via respiration and perspiration) heat form. Different values are given in the literature [20][21], the heat diffusion (W) from the occupants' activities are given by table 2. The general equation that gives the values of internal gains is given by the following expression:…”

“…The solar gains depend on the incident solar radiation, the orientation of the receiving surfaces and some characteristics such as: shading, transmission and absorption coefficients. This energy gain will be calculated according to the following equation [20,22]:…”