Efficient solar collection beyond the etendue limit

TL;DR

This paper introduces a novel multi-element telecentric lens array that significantly enhances photovoltaic efficiency at large solar incidence angles, surpassing traditional etendue limits and enabling better energy capture throughout the day.

Contribution

The authors demonstrate a custom lens array that increases open circuit voltage at high incidence angles, extending PV performance beyond the conventional etendue limit.

Findings

132% increase in Voc over a full day at +/-80 degrees incidence

Increased field of view without violating etendue conservation

Prototype suggests potential for mass production and easy integration

Abstract

Photovoltaics (PV) are a versatile and compact route to harness solar power. One critical challenge with current PV is persevering the optimal panel orientation angle with respect to the sun for efficient energy conversion. We experimentally demonstrate a bespoke array of multi-element telecentric optical lenses that allow for a greatly increased open circuit voltage (Voc) at solar incidence angle of between +/-80 degrees compared to a standard panel. Our prototype lens-let shows a 132% increase in Voc over a full day, at optical incidence angles of +/-80 degrees. This many element array provides increased field of view without breaking the conservation of etendue. Our prototype indicates that this lens-let array could potentially be mass produced and be readily installed onto any PV system.