EVA: Fair and Auditable Electric Vehicle Charging Service using Blockchain

The recent success of electric vehicles leads to unprecedentedly high peaks of demand on the electric grid at the times when most people charge their cars. In order to avoid unreasonably rising costs due to inefficient utilization of the electricity infrastructure, we propose EVA: a scheduling system to solve the valley filling problem by distributing the electricity demand generated by electric vehicles in a geographically limited area efficiently over time spans in which the electric grid is underutilized. EVA is based on a smart contract running on the Ethereum blockchain in combination with off-chain computational nodes performing the schedule calculation using the Alternating Direction Method of Multipliers (ADMM). This allows for a high degree of transparency and verifiability in the scheduling computation results while maintaining a reasonable level of efficiency. In order to interact with the scheduling system, we developed a decentralized app with a graphical frontend, where the user can enter vehicle information and future energy requirements as well as review upcoming schedules. The calculation of the schedule is performed on a daily basis, continuously providing schedules for participating users for the following day.