As the global push for carbon neutrality accelerates, managing the massive energy demands and waste heat of industrial sectors has become a critical challenge. Industrial energy systems currently account for nearly 40% of global electricity demand growth. To address this, scientists are increasingly turning to a promising long-duration energy storage technology: the Carnot battery.
A newly published study in the journal ENGINEERING Energy by a research team from Zhejiang University and affiliated institutes offers a major breakthrough in making Carnot batteries more practical and efficient for real-world industrial applications. The researchers have developed a novel "quasi-dynamic" mathematical model to optimize Thermally Integrated Carnot Batteries (TI-CB) under the unpredictable, fluctuating conditions typical of factory environments.
The Challenge of Fluctuating Waste Heat Unlike conventional lithium-ion batteries, Carnot batteries store excess electricity in the form of thermal energy (heat) by creating a temperature difference between hot and cold reservoirs. When the grid needs power, this stored heat is converted back into electricity. TI-CB systems, which utilize an Organic Rankine Cycle (ORC), are particularly well-suited for capturing and upgrading low-to-medium grade industrial waste heat (typically between 60°C and 90°C).
However, real-world industrial environments are rarely perfectly stable. Waste heat temperatures and flows fluctuate constantly. "Most previous studies relied on steady-state models that fail to capture the dynamic nature of industrial waste heat conditions," the research team explains. "Our goal was to understand how these systems perform when operating under off-design, fluctuating conditions over long periods."
A New Modeling Framework To solve this, the researchers developed a quasi-dynamic mathematical model paired with a dynamic evaluation framework that accounts for the time delays between charging and discharging phases. By running thousands of simulations using multivariable sampling, they could systematically observe how different design parameters influence overall efficiency.
Key Findings for Future Engineering The study yielded several crucial insights for the future commercial deployment of Carnot batteries:
This comprehensive modeling approach bridges the gap between theoretical thermodynamics and practical engineering. By providing a clear roadmap for how to handle off-design fluctuations, this research brings Carnot batteries one step closer to widespread deployment, offering a powerful tool to decarbonize industrial parks and stabilize grids powered by intermittent renewable energy.
ENGINEERING Energy
Experimental study
Not applicable
Performance optimization of thermal integrated-Carnot battery for waste heat utilization in industrial integrated energy systems
25-Jan-2026