J.O. Aguilar

Design, construction, and testing of a parabolic trough solar concentrator for hot water and low enthalpy steam generation

This paper reports the design, construction, and evaluation of a solar parabolic trough concentrator (PTC) with a rim angle of 45°, a length of 4.88u2009m, and an aperture area of 5.8 m2. The PTC is made of aluminium in such a way that both the manufacturing and assembly processes do not require complicated technology or skilled labour. Since the PTC is for low enthalpy steam generation and hot water, it is designed with an unshielded receiver and without a glass cover in order to reduce both production and transportation costs. A finite element stress analysis is conducted to determine the mechanical behaviour of the PTC under various simulated wind loads on the structure. A simple solar tracking system is employed when it is oriented in a North-to-South direction. The optical efficiency of the collector is also reported. Said efficiency depends on the optical properties of the materials involved, the geometry of the collector, and the various imperfections arising from the construction of the collector. The...

Parabolic trough concentrators for hot water generation: Comparison of the levelized cost of production

With the objective of demonstrating the technical and economic viabilities of a hybrid solar energy system applied to hot water generation, a simulation of a parabolic trough power plant with an auxiliary electrical heater system is presented. This article reports the procedure to obtain the characteristic equation of the useful heat value when N parabolic troughs are operated in series; the equation takes into account the heat loss through the pipes and the use of a heat exchanger. Additionally, this work reports a theoretical case study of a hybrid system that supplies hot water via solar energy and an auxiliary electrical system. The solar fraction and the global efficiency of the hybrid solar power plant are calculated. Using the results from the simulation, a cost analysis of the hybrid solar power plant was done where the levelized cost of thermal power generated is obtained; this in turn shows that the levelized cost of a conventional electrical heater system is one and a half times more than that ...

A Modular Linear Fresnel Reflecting Solar Concentrator for Low-Enthalpy Processes

One of the aims of solar-thermal engineering is to develop ‘medium temperature collectors’ in the range of 70–250 °C that are suitable for applications such as cleaning, drying, evaporation, distillation, pasteurization, sterilization and cooking, as well as applications with low-temperature heat demand and high consumption rates (domestic hot water, space heating and swimming pool heating), and heat-driven refrigeration and cooling. In this work, we present an applied research on the development of a modular linear Fresnel reflecting solar concentrator (MLFRC) for heating water and steam generation at low enthalpy in the temperature range of 70–110 °C. We present a simple mathematical method to determine the distance among the reflecting elements and the angle for each one in order to avoid shading between the elements during the period of operation. We designed a non-imaging CPC cusp-type collector with a cylindrical receiver as a secondary concentrator. We also evaluated the thermal performance of MLFRC according to the Standard ANSI/ASHRAE 93:2003.