Dominik Pelzer presents a framework for investigating and optimizing the profitability of energy storage systems. The author deploys the methodology to assess the benefits of electric vehicle smart charging and to investigate the financial viability of arbitrage using battery energy storage systems. He evaluates the factors influencing profitability and identifies conditions for profitable operation. Due to the framework's modular design, these considerations can be extended to a large variety of storage technologies and scenarios to identify optimal operating parameters.