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This manuscript is about the electric output of the silicon (Si) photovoltaic (PV) cell versus the electromagnetic field of a radio wave and a monochromatic illumination in three-dimensional (3D) assumptions. The polarisation direction of the electromagnetic wave and power density are fixed. The electromagnetic wave is provided by electromagnetic emission sources such as the telecommunication, radio, or TV antennas. A PV system is installed in the vicinity of an electromagnetic emission source. The current produced by the PV cell is sensitive to electromagnetic field increase more than the electric voltage. The electromagnetic field causes the decomposition of the current into two components which are a transferred current and a leakage current. The transferred component provides the transmitted current to the external load while the leakage component gives the loss of the carrier charge into the junction. Consequently, this decomposition of the current shares the electric power in transferred electric power and leakage electric power. The transferred electric power is obtained only in the intermediate circuit, and the maximum power point (MPP) shifts to the short circuit situation as the junction dynamic velocity becomes the greatest. However, the leakage electric power corresponds to a loss of the minority carrier’s charge in the junction during the crossing of the junction. This loss causes a Joule heating effect of the junction. The heating of the junction causes the quality degradation of the PV cell mainly due to the electric component. The solar illumination wavelength is presenting the inversion phenomenon with the maximum of the electrical outputs of the silicon PV cell of around 0.70 μm which provides the greatest conversion efficiency. This value has been chosen for the modelling of the radio wave influence. Hence, the conversion efficiency increases when the PV system is far away from the electromagnetic emission source. PV system installation in the vicinity of an electromagnetic emission source is not advised.

Thermal comfort is one of the most important requirements that scientists and building designers must meet to ensure the indoor air quality knowing its importance on productivity and the health of occupants. However, it has never been of great concern for architects and architectural historians and seldom explores it. Buildings are the large consumer of the most energy consumption (around 40% worldwide) and generate around 35% of GHGs like CO2 that leads to extreme climate change. Hence, general and specific eco-friendly solutions in the field of building construction are required. Analysis of this study shows that air conditioning consumption can be significantly reduced thanks to the compressed earth bricks and by taking into account the climate and the orientation of the facades. However, this paper establishes viable low-cost option of building energy consumption while maintaining the thermal comfort and good indoor air quality. This work explains the effect of a single residential room orientation, by reducing the thermal amplitude, and improving the thermal phase shift in Ouagadougou climate conditions in April. Internal temperature was modelled with 8 cardinal orientations. The result corresponds to a decrease of thermal amplitude damping greater than 4°C between East-West and North-South sides and, with a thermal phase shift of 4 hours 30 minutes between the Nord and West walls.

The energy demand in buildings sector is always increasing due to the climate, the economic growth, and also the need for thermal comfort. The aim of this paper is to find a way that can significantly reduce the energy demand for a building through an improvement of the design of its thermal envelope. Within this work, we utilized the thermophysical properties of four building materials: three local materials (compressed earth block (BTC), lateritic block (BLT), and raw earth), and one modern (Hollow cement). The numerical optimization of the building design has been performed dynamically by Comsol 5.3a software: the case study is Ouagadougou and the surface is 100m2. Also, the temporal variations in the inside of the room, as well as the internal and external temperatures of the walls and the ceiling with four different materials, have been determined. The result of the simulation shows that, for BLT, the maximum of ambiante temperature is obtained 308K around 22h, for Adobe it is 308.8K around 21h, for BTC it was 309.2K at 19h30, and finally for cement block it is 310K around 17. We can safely say that BLT is the material leading to the lowest average daily indoor temperature variation, thus leading to the reduction of air conditioning load and the need for thermal comfort and around the order of 4KW of energy saving can be obtained.