Douglas Yeboah

Wind energy is a reliable renewable source of energy with significant technological advancements. However, recovering wind energy from waste and predictable sources remains untapped. Certain industrial activities emit pollutants while generating wind energy, presenting opportunities for cleaner energy utilization. This study investigates wind energy recovery from an underground mine’s exhaust through experimental research and analysis. It revealed a drop in wind velocity at −2.5162 Hz frequency as distance increased. This frequency predicted a wind speed of 7.67 m/s at 1 m from the exhaust fan in a real mine. Theoretical calculations show significant wind energy potential of 1031.31 kWh over 13 hours, which is equivalent to 79.3 kW. Realistic estimates suggest 55.51 kW wind power can be recovered, yielding 721.63 kWh. Compared with previous studies in the mining industry, recovery potential varies based on site-specific factors. The study shows a recoverable power percentage of 28% ...

In recent years, thin film organic solar cells (OSCs) and perovskite solar cells (PSCs) based on solution processable organic semiconductors and perovskites, respectively, have attracted huge research interests as promising alternatives to conventional silicon solar cells, owing to their appealing features such as lightweight, large area production capabilities, low fabrication cost and mechanical flexibility. Although, OSCs have achieved power conversion efficiency (PCE) of about 12 %, it is still lower than 25 % obtained in silicon solar cells. In comparison, the PCE of perovskite solar cells has reached more than 22 %, which is much better but both OSCs and PSCs have a stability problem; their working lifetime is very short. As a result, both OSCs and PSCs have not reached the commercialization stage yet. Hence, the understanding of physical processes that govern the operation and stability of organic and perovskite solar cells is very crucial in order to find pathways to enhance...

Perovskite solar cells are regarded as a promising alternative for the next generation solar cells. Despite a significant improvement in their power conversion efficiency (PCE), the dependence of open circuit voltage ( ) OC V on material parameters has not been fully understood. We have derived two analytical expressions for the OC V in perovskite solar cells as a function of material parameters, such as electron (hole) mobility ( ) e h μ μ ,electron-carrier concentration (n),effective density of states of holes at the at the valence band edge ( ) V N , photo generation rate G , active layer thickness(d)and electron drift velocity ( ) e v . It is found that using perovskite materials with low V N , higher electronhole mobility ratio ( ) e h μ μ , and larger active layer thickness at high light intensity can lead to higher OC V and hence higher PCE in perovskite solar cells, which agree well with experimental results. These results may provide useful guidance in selecting materials l...