Dynamic Optimization of Proton Exchange Membrane Water Electrolyzers Considering Usage-Based Degradation

TL;DR

This paper develops a comprehensive optimization model for PEM electrolyzers that accounts for usage-based degradation, revealing its impact on costs, lifespan, and system design under different future scenarios.

Contribution

It introduces a novel integrated model that combines physics, operational constraints, and empirical degradation data for PEM electrolyzers, enabling more accurate techno-economic assessments.

Findings

Including degradation increases hydrogen costs and shortens electrolyzer lifespan.

Future cost reductions will enable larger, longer-lasting electrolyzers with less storage.

The model is adaptable to other electrochemical systems for decarbonization.

Abstract

We present a techno-economic optimization model for evaluating the design and operation of proton exchange membrane (PEM) electrolyzers, crucial for hydrogen production powered by variable renewable electricity. This model integrates a 0-D physics representation of the electrolyzer stack, complete mass and energy balances, operational constraints, and empirical data on use-dependent degradation. Utilizing a decomposition approach, the model predicts optimal electrolyzer size, operation, and necessary hydrogen storage to satisfy baseload demands across various technology and electricity price scenarios. Analysis for 2022 shows that including degradation effects raises the levelized cost of hydrogen from \$4.56/kg to \$6.60/kg and decreases stack life to two years. However, projections for 2030 anticipate a significant reduction in costs to approximately \$2.50/kg due to lower capital expenses, leading to larger stacks, extended lifetimes, and less hydrogen storage. This approach is adaptable to other electrochemical systems relevant for decarbonization.