Li-Ion Battery versus Pumped Storage for Bulk Energy Storage - A Comparison of Raw Material, Investment Costs and CO2-Footprints

摘要

The balancing of load and generation is a major challenge in electricity systems shaped by renewable energy sources. In this context, large-scale storage systems as a temporal flexibility option contribute to the balancing process by participating in portfolio management, energy only markets as well as system reserve markets. Over the past years particularly battery storages experienced a tremendous ‘hype’ in public discussions due to technological innovation and a significant cost decrease. As a result, several new stationary battery storages in the order of magnitude of hundreds of megawatt hours have been constructed during the last decade. However, the question remains whether the falling costs of a stationary battery storage can be competitive with well-established technologies such as pumped storage hydro. This paper compares the marginal costs given by the specific raw material costs of a representative stationary battery storage with the respective costs of a pumped storage scheme. It is evident that both systems need completely different types and quantities of resources leading to substantial differences in their specific raw material costs. In addition to the raw material costs, annual lifetime investment costs and land requirements for both technologies were examined. Finally, the different contributions to the over-all CO2-footprint are analyzed. This paper, consequently, contributes to the ongoing and controversial discussions around the different storage technologies for stationary application with respect to their economic efficiency and their environmental impact.