Optimal energy purchasing and balancing services provision of a bus fleet operator

The EU aims to reduce carbon emissions by increasing the use of renewable energy. However, the volatility of wind and solar power can cause issues for the power grid. Sector coupling can help to ensure grid reliability. Electric vehicles can be used for sector coupling through vehicle-to-grid technology. This requires coordination between vehicle owners, electricity producers, and grid operators. However, frequent full battery cycles accelerate aging and increase total cost of ownership. Our method optimizes the benefits of sector coupling for a bus fleet operator, considering aging mechanisms, and shows significant advantages during regular operation under the assumptions of perfect foresight regarding price development, i.e. the consistent achievement of median market prices. We investigate different scenarios for the amount of actual control energy activated and demonstrate that it is economically feasible to participate in the energy-only balancing market already for a share as low as one percent control energy of the offered capacity.