Given the strong penetration of electric vehicles (EVs) and renewable energy sources, battery demand is dramatically increasing. To satisfy this huge request for batteries, a possible solution, taking into account a circular-economy framework, is given by second-life batteries (SLBs), a new technology that exploits deteriorated batteries from the EV sector for less demanding applications, such as stationary storage. On the one hand, SLBs make it possible to use batteries to their full extent. On the other hand, specific standards for SLBs are still missing and, from an industrial point of view, there are several factors that influence whether this business would be convenient or not. This article presents a possible lifecycle for EV batteries where SLBs are considered with different business strategies, also taking into account the possible SLB applications that can be derived from the reuse of batteries before being recycled. From an economic point of view, an economic assessment is introduced, providing possible parameters that may affect the SLB business either positively or negatively.

This paper presents an economic assessment of seawater thermal energy storage (TES) integrated with industrial heat pumps to couple renewable electricity generation with urban district heating networks. Using Amsterdam as a case study, we develop a techno-economic model leveraging real-world data on electricity prices, heat demand, and system costs. Our findings show that large-scale TES using seawater as a storage medium significantly enhances district heating economics through energy arbitrage and operational flexibility. The optimal configuration yields a net present value (NPV) of EUR 466 million over 30 years and a payback period under 6 years. Thermal storage increases NPV by 17% compared to systems without storage, while within-day load shifting further boosts economic value by 23%. Accurate demand and price forecasting is critical, as forecasting errors can reduce NPV by 13.7%. The proposed system is scalable and well suited for coastal cities, offering a sustainable, space-efficient solution for urban decarbonization and addressing renewable energy overproduction.