Thermal Analysis of Parabolic Trough Solar Collector and Assessment of Steam Power Generation at Two Locations in Cameroon

Abstract

The supply of electrical energy to households remains a major concern in Cameroon. Over the past two decades, the state has devoted enormous financial resources to the construction of thermal power plant working on Heavy Fuel Oil. Despite this effort, it has been noted that the production of electricity from fossil sources has not been up to the expectations of the population because the production cost that remains quite high limits the supply to major urban centers. In this context, it becomes a necessity to explore other sources of production and in particular renewable sources. This paper is concerned with the study of the steam production potential in the stations of Maroua and Yaoundé in Cameroon using Parabolic Trough Collectors. Two production modes are considered in this study which are: The direct mode using water and the indirect mode with TherminolVP1 as heat transfer fluid. The modeling of the system is based on the study of the energy balance of heat exchange between the receiver and the calorific fluids in order to assess the impact of incident solar irradiation on the fluid outlet temperature for each generation mode. Using PVGIS solar data, the outlet temperature profile of water as well as the thermal power generated and the system efficiency for different series associations using a variable number of collectors were analyzed. It was shown that the temperature of the steam increases with the increase in the number of collectors. For an association of 8 collectors, the average daily production time of pressurized steam at 40bars is 8 hours with a maximum temperature of 600 °C in direct mode and 490 ° C in indirect mode for the month of February in Maroua. The maximum efficiency for the same month is 72.7% in direct generation and 60.7% in indirect generation. These results confirm the possibility of energy generation combining solar sources with existing heavy fuel oil stations for better efficiency. However, further investigations about the energy demand and the supply are necessary for appropriate sizing of the solar generator.