Trade-EVs II – Trade of Renewable, Aggregated and Distributed Energy by Electric Vehicles
In the Trade-EVs II project, various intelligent charging strategies for electric vehicles were investigated. Such charging strategies can reduce the operating costs of electric vehicles, but their implementation is hindered by regulatory and technical challenges. The Trade-EVs II project has shown that the implementation of smart charging strategies is technically realizable. Annual savings of several hundred euros per vehicle can be achieved and the entire energy system can benefit.
Motivation
Electric vehicles offer a climate-friendly alternative to conventional vehicles with combustion engine and help to reduce CO₂ emissions in the transport sector. They are therefore a key technology in the fight against man-made climate change. However, increased electricity prices as a result of the energy crisis pose a challenge for the broad market launch of electromobility. However, intelligent charging strategies can make targeted use of price fluctuations on the electricity market and reduce costs. In addition, bidirectional charging enables surplus energy to be fed into the grid, which can generate additional revenue.
Use Cases and Regulation
Relevant use cases for controlled and bidirectional charging were identified at the beginning of the project. The unidirectional use case of spot market-optimized charging of electric vehicles was selected for the field test. The use cases of peak shaving, provision of primary control power and arbitrage trading were investigated using simulations. The use cases were each documented in standardized profiles and visualized using an e3 value model.
The implementation of these use cases is hindered by various technical and regulatory challenges. These challenges were investigated in the project as part of the accompanying research for the field trial. A non-static electricity tariff is required to implement the spot market-optimized charging use case. The legal background of non-static electricity tariffs was examined in a paper.
Further Information:
Field test
The use case of spot market-optimized charging was tested in the field test of the overall project. The fleets of the project partners SAP, Nextmove and EWS were aggregated and integrated into a virtual power plant. Coneva took on the role of technical aggregator and EWS the role of energy supplier. The FfE provided scientific support for the field test, and energy was procured at optimized prices on the spot market, taking fleet availability into account. The field test thus demonstrated the feasibility of spot market-optimized charging.
Revenue potential
In addition to the field test, various use cases were simulated using the eFlame optimization model. The simulation results show that annual revenues of several hundred euros per vehicle can be generated with the investigated use cases. Due to higher price spreads, higher revenues could be achieved on the intraday market than on the day-ahead market. Due to particularly high price volatility, the highest revenues were achieved in 2022. The combination of different use cases (multi-use) and markets is possible. By combining different spot markets, revenues can be almost tripled compared to the day-ahead market.
Further Information:
- Is charging electric vehicles with variable tariffs worthwhile? Attractiveness for electric vehicle drivers and business model potential for electricity providers and aggregators – FfE
- Opportunity or risk? Model-based optimization of electric vehicle charging costs for different types of variable tariffs from a consumer perspective
- Assessing the incorporation of battery degradation in vehicle-to-grid optimization models
Energy system impact
Both individual users of electric vehicles and the entire energy system can benefit from intelligent charging strategies. The energy system model ISAaR was used to investigate the impact of bidirectional electric vehicles on the energy system. For this purpose, a scenario without bidirectional electric vehicles (Ref) and a scenario with bidirectional electric vehicles (bidi) were analyzed. The results show that bidirectional electric vehicles contribute to a more efficient use of the overall system. The total costs of the energy system can be reduced by up to €11.6 billion per year, resulting in lower electricity costs. Fossil energy generation and the expansion of stationary battery storage can be reduced.
Projektpartner
For the Trade-EVs II project, FfE formed a consortium together with the partners SAP SE, CYX mobile KG (Nextmove) and EWS.
Funding
The research project was funded by the Federal Ministry of Economics and Climate Protection (BMWK) (funding code: 01MV20006E).