# Unfolding Electrolyzer Characteristics to Reveal Solar‐to‐Chemical Efficiency Potential: Rapid Analysis Method Bridging Electrochemistry and Photovoltaics

## TL;DR

This paper introduces a rapid method to evaluate how efficiently solar energy can be converted into chemical fuels using electrolyzers combined with solar panels.

## Contribution

A new rapid assessment method is introduced to evaluate solar-to-chemical efficiency by unfolding electrolyzer characteristics.

## Key findings

- The method uses power balance requirements to convert EC characteristics into PV-EC system parameters.
- It enables assessment of solar-to-chemical efficiency under various irradiance and power coupling conditions.
- The approach is verified with CO2-reduction electrolyzer analysis and PV-EC experiments.

## Abstract

Development of photovoltaic−electrochemical (PV‐EC) systems for energy storage and industry decarbonization requires multidisciplinary collaborative efforts of different research groups from both photovoltaic and electrochemical research communities. Consequently, the evaluation of the solar‐to‐chemical or solar‐to‐fuel efficiency of a new electrolyzer (EC) as a part of a PV‐EC system is a time‐consuming task that is challenging in a routine optimization loop. To address this issue, a new rapid assessment method is proposed. This method employs power balance requirements to unfold the input EC characteristics into the parameter space of PV‐EC systems. The system parameters, composed with the EC output characteristics, yield the solar‐to‐chemical efficiency attainable by the electrolyzer in combination with any PV device under any irradiance at any relative PV‐to‐EC scaling and any mode of power coupling. This comprehensive overview is achieved via a mathematically simple conversion of the EC characteristics in any spreadsheet software. The method, designed to streamline the development and minimize the efforts of both the photovoltaic and electrochemical communities, is demonstrated via the analysis of CO2‐reduction electrolyzer characteristics and verified with dedicated PV‐EC experiments.

A method of unfolding current‐voltage characteristics of electrochemical (EC) cells to assess solar‐to‐chemical efficiencies achievable in combination with any photovoltaic (PV) device under any irradiance, PV‐to‐EC scaling, and power coupling mode. A comprehensive overview is achieved through a mathematically simple conversion of the EC characteristics in any spreadsheet software.