In the realm of energy storage solutions, a team of researchers from Universidad Carlos III de Madrid has been exploring the potential of Power-to-Heat-to-Power Storage (PHPS) systems, also known as Carnot batteries. These systems could play a significant role in energy markets dominated by wind and solar power.
The study, published in the journal Applied Energy, evaluates the role of PHPS systems in the national energy systems of Denmark, a wind-dominated region, and Spain, a solar-dominated region. The researchers used the open-source PyPSA framework to model sector-coupled electricity and heating systems. They assessed individual and district heating configurations for residential heat provision, with and without PHPS waste heat recovery.
The results indicate that PHPS systems are most viable in individual heating systems, particularly in wind-dominated locations like Denmark. The low cost per energy capacity of PHPS systems enables them to balance long-duration fluctuations in energy supply. Waste heat recovery is crucial for enhancing the competitiveness of PHPS systems, allowing them to displace lithium-ion batteries. However, in district heating systems, PHPS systems are largely outcompeted by low-cost centralized energy storage solutions.
The viability of PHPS systems depends primarily on achieving low energy capacity costs and maintaining reasonable heat-to-power conversion efficiencies. While PHPS systems can complement existing storage technologies by providing dispatchable electricity and heat, their potential adoption is highly context-dependent. Factors such as climate, heating system configuration, and competing storage costs all influence the feasibility of PHPS systems.
For the energy industry, this research highlights the potential of PHPS systems as a complementary storage solution, particularly in wind-dominated markets and individual heating systems. However, the practical application of PHPS systems will require further reduction in energy capacity costs and improvements in heat-to-power conversion efficiencies. Additionally, the integration of waste heat recovery can significantly enhance the competitiveness of PHPS systems against other storage technologies.
This article is based on research available at arXiv.