Modelling of a Solar Heating System for Industrial Processes using Linear Fresnel Reflectors

Thermal energy in industries has a significant share of the total energy consumed by different processes in the industrial sector. In solar energy rich countries, like Libya, this can be significantly provided by solar energy technologies. Dairy factories involve a number of processes requiring heat at different temperatures. Some processes even require steam at high temperatures. Pasteurization, sterilization, cleaning, washing, and evaporation are some of the operations in dairy processing plants. Concentrated solar power plants can provide such high temperatures using a number of technologies, specifically parabolic trough reflectors, linear Fresnel reflectors, parabolic dish, and the central receiver with a heliostat field. Libya is located in the sun belt and is pleasant with high levels of sun radiation. This paper investigates the techno-economic feasibility of a concentrated solar power plant utilizing linear Fresnel reflectors technology to provide heat for the pasteurizing process at a proposed milk processing diary. A production rate of 100,000 liters per day of milk was assumed. All of the parameters involved in the design process, such as the available area, solar energy available at the location, energy demand of the process, inlet and outlet temperatures, energy storage requirement, and cost per unit of electricity, were fed to the Ressspi platform, a solar simulator for industrial processes. Results showed that the system is highly feasible in terms of technical as well as economic aspects. The heat generated by the solar plant was 1260661.4 kWh, while that consumed by the process was 1321636.8 kWh and that represents 95.4% of the energy needed for the process. The solar utilization factor is 77.1% as a result of energy lost due to defocusing of the Fresnel reflectors. The payback period of the project was found to be 5 years with an internal rate of return of 23.88% and a levelized cost of energy of 0.03228 €/kWh.