An experimental study on the thermal properties of iron filings and steel-fiber-reinforced concrete for solar/thermal energy storage application is presented in this report. It takes into account the results of measurements of thermal conductivity, thermal resistivity, thermal diffusivity and the results of compressive strength, density as well as energy storage capacity calculated from the knowledge of the above measured parameters. The experimental testing method is described as well: based upon the linear heat source theory, it requires the use of a special probe to be inserted into the sample. The experimentation was forwarded to test concrete aggregate mixtures with three different sizes and same quantity of steel fibers; two different quantities of iron filings and one plain concrete. The measurements were carried out from the pouring time of cubic samples and were ended up when hardened conditions were achieved. The results indicate that the steel fibers and iron filings have influence on the thermal and mechanical properties of the concretes tested, thus the iron filings and steel fibers reinforced concrete is suitable for better solar/thermal energy storage due to an increase in storage capacity over plain concrete.

Thermoelectric devices use the Peltier effect which creates a heat flux between the junctions of two different types of materials. The thermoelectric module also referred to as a heat pump transfers heat from one side to the other when a DC current is applied. This study carried out the theoretical and experimental analysis of a thermoelectric air conditioning system. A prototype thermoelectric air conditioner of 286 W cooling capacity was built and a testing enclosure made from plywood and Styrofoam was also constructed in order to validate the theoretical result with an experimentation. It was discovered that thermoelectric air conditioning took 4 minutes to reach its desired temperature of 22℃ whereas the standard air conditioning system (Refrigeration Cycle) took 20 minutes to cool to a room temperature. Economically it was also discovered that thermoelectric air conditioning system is 50% cheaper than the refrigeration cycle air conditioning systems. The thermoelectric air conditioner has cheaper maintenance and greater estimated life span of 7 years more than the refrigeration air conditioner. This is because the air conditioner that operates on the refrigeration cycle uses a rotating compressor while the thermoelectric air conditioner uses thermometric module.

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  Abstract-The study investigates the concentrations of CO, NO 2 , SO 2 , CO 2 and HC arising mainly from the activities of motor vehicles, on the ambient air quality of selected sites in the Lagos metropolis and the locations of Oshodi, Ojota, Yaba and Lekki. The final location (Lekki) was used as a control.Results from dry season vehicular emission monitoring indicate that the average CO concentration at the Oshodi site peaked at 29.04 ppm. The site also recorded the highest concentrations for NO 2 , SO 2 , CO 2 and HC at 0.042ppm, 0.040 ppm, 370.92 ppm and 0.030 ppm respectively. In the wet season, Oshodi also recorded highest CO concentrations at 18.72 ppm. NO 2 was highest at 0.03 ppm in Yaba and Ojota. Both Oshodi and Ojota areas recorded the highest SO 2 concentration at 0.032 ppm. Oshodi recorded the highest concentrations for both CO 2 and HC at 370.92 ppm and 0.028 ppm respectively.