Design method for nonimaging solar photovoltaic concentrators using genetic algorithms

Abstract

Off-grid solar chargers are one of the ways forward to achieve universal access to affordable, reliable, sustainable and modern electricity. To achieve this goal, the sustainability aspect of the solar chargers must be further improved. Nonimaging, static solar photovoltaic (PV) concentrators reduce the amount of PV material and thus the embodied energy and greenhouse gas emissions of the solar PV panel, improve its recyclability and reduce the use of hazardous chemicals during its manufacturing, recycling and disposal stages. A novel nonimaging solar PV concentrator named circular rotational square hyperboloid (CRSH) was recently proposed for portable solar systems for developing countries. To further reduce the material usage and production time of the concentrator while achieving an optical concentration ratio above 3x within the angles of incidence of ± 40º, the parameters of the design were optimised using genetic algorithms. The optimisation parameters are discussed and the influence of the objective function on the optimised design is presented. The genetically optimised circular rotational square hyperboloid (GOCRSH) concentrator shows an improved gain-to-volume ratio compared to the CRSH and to several nonimaging solar photovoltaic concentrators proposed for building integrated concentrated PV.

Design method of a compact static nonimaging concentrator for portable photovoltaics using parameterisation and numerical optimisation

“…Figure 1shows a simplified flowchart of a GA used in this optimisation [34]. The preliminary results of the concentrator optimisation were published in [35] which…”

“…To be able to numerically optimise the CRSH concentrator, the concentrator surfaces need to be in a parametric form. The initial CRSH design has a rotationally symmetric entrance aperture designed point by point, a hyperbolic side-profile and a 100 x 10 -6 m 2 square exit aperture [35]. The point by point created entrance surface aperture can be approximated in 2D…”

“…This function describes how close the performance of the evaluated concentrator design is to the desired performance or how it compares to that of other concentrators within the population. As described in the previously published conference paper [35] the objective function was developed stepwise using experimental testing. The choice of the objective function influences the resulting concentrator volume, concentrator height and the average Copt±40º of the optimised concentrator design.…”