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Investigating the Effect of an Ir Emitting Element to the time Constant of Solar Energy Harvesting Device Lifetime
No full textSolar photovoltaic (PV) system is instrumental in provision of sustainable energy in the wake of social and environmental concerns. While research in solar cell efficiency has made great strides and achieved over 40%, key concern is however, reasonably extending the time constant of the solar cell lifetime in minimum or no insolation. This emanates from the fact that most of the solar cells have solid power storage which runs out under limited insolation and hence reducing the reliability of the cells. Therefore, innovation in PV is likely to rely not only on high efficiency PV with flexible and lightweight thin films, but also on reliability of the PV which can be guaranteed by ensuring the longest output time of the PV in limited insolation. This paper investigated the effect of an infra-red generating element on the time constant of a solar cell lifetime when the element is placed adjacent to the solar cell. Using a dye-sensitized solar cell (DSSC) using TiO2 electrode, maintaining the topology, thermal escape mechanism, quantum structure and optical absorption of In(Ga)As quantum dots in a wide gap Al0.2GaAs host material, the study investigated the effect of an IR emitting element on the solar harvesting device lifetime. The study shows that there was a minimum of 27% increase in power output under low irradiation while 14% increase in power output was recorded for high irradiation when an IR diode is mounted adjacent to solar cell. We conclude standardized IR element adjacent to a solar cell in a PV system can significantly stretch a solar cell lifetime and power output
Climate Change and Immovable Cultural Heritage in Kenya: Impact and Response Strategies
No full textImmovable cultural heritages represent past human life that links the past, present, and future landscapes. Protection and preservation of authenticity and integrity of these built heritages is a major challenge in the twenty-first century. Increased number of extreme weather events associated with climate change is a major concern in management and conservation of cultural heritage around the globe. This study assessed climate change impacts on immovable cultural heritage and the response strategies being employed along Kenya’s coastline. Two counties in the coast region (Mombasa and Kilifi) were chosen for the study because of their rich cultural heritage surrounded by natural hazard-prone environment which has seen some of the sites listed to be in danger due to climate change. Through engagement with practitioners responsible for management of the sites, the following elements were looked into: sea level rise, coastal flooding, temperature rise, coastal winds, coastal erosion, increased precipitation, and increase in acidity levels. Data was collected through observation, interviews, and administering of questionnaires in the eight immovable cultural heritage sites in Mombasa and Kilifi counties. Findings indicate that the immovable cultural heritage sites are greatly affected by the climatic changes. Presence and growth of plants, corroded metallic parts, cracks, fallen walls, rotten wooden parts, submerged structures, and flaked walls have been acerbated by extreme weather-related events. Furthermore, despite climate changes being a major threat to these sites, it has not been included in cultural management plans. Inadequate resources are the main barrier in adapting to climate change. Structural and managerial strategies employed in the management of heritage sites in the region are highlighted