This paper analyzes the business case of offering secondary downward reserve for frequency control on the German market by a pool of electrical vehicles. Former benchmark studies promised high revenues especially for this case. The benefits could provide an incentive to customers to buy an electric vehicle. The business case is analyzed for the German market as a case study. Specific regulations for this market, real driving patterns and real market data are taken into account when calculating revenues. Secondary reserve is strictly regulated, requiring a very high level of availability. As a result, simulated revenues are lower than assumed. Simulation shows average revenues of less than 5 € per month and vehicle. As a major bottleneck for an offer of secondary reserve, fully charged batteries are identified. Additionally an issue is made of costs for communication and customer compensation. Based on the simulation results, it is argued that the market for secondary reserve should not be accessed with these small units. For electric vehicles, easier accessible markets with lower related costs should be considered instead.