Luminescent solar power: PV/thermal hybrid electricity generation for cost effective dispatchable solar energy

TL;DR

This paper introduces luminescent solar power (LSP), a hybrid PV/thermal system that enhances solar energy dispatchability and reduces costs by combining photoluminescent absorption with thermal storage.

Contribution

The paper presents a novel LSP concept that integrates photoluminescent materials with PV and thermal storage, enabling cost-effective, dispatchable solar energy.

Findings

Supports an additional 1.5kWh PV electricity per 1 kWh heat energy

Demonstrates experimental feasibility of the hybrid system

Potential to lower solar energy costs for base-load applications

Abstract

The challenge in solar energy today is not the cost of photovoltaic (PV) electricity generation, already competing with fossil fuel prices, but rather utility-scale energy storage and flexibility in supply. Low-cost thermal energy storage (TES) exists but relies on expensive heat engines. Here, we introduce the concept of luminescent solar power (LSP), where sunlight is absorbed in a photoluminescent (PL) absorber, followed by red-shifted PL emission matched to an adjacent PV cell's band-edge. This way the PV cell operates nearly as efficiently as under direct illumination, but with minimal excessive heat. The PL-absorber temperature rises due to thermalization, allowing it to store the excessive heat, which can later be converted into electricity. Tailored luminescent materials that support an additional 1.5kWh PV-electricity for every 1 kWh of (virtual) heat engine-electricity, with a dynamic shift between the two sources are experimentally demonstrated. Such an ideal hybrid system may lead to a potential reduction in the cost of electricity for a base-load solution.