Research on the valley-filling pricing for EV charging considering renewable power generation

The real-time dispatch of electricity grids faces two new challenges: the volatility of renewable energy power generation and the impact caused by the large-scale charging demand of electric vehicles (EVs). Under the premise that China's renewable energy power generation is a prior connection to the grid, this article aims to guide the coordinated charging of EVs through the design of the time-of-use charging price mechanism and to help achieve valley-filling. The peak and valley hours were divided according to the load of baseload units that do not include renewable energy power generation. A nationwide discrete choice experiment has been conducted to investigate the willingness to pay of 2637 Chinese consumers for charging at different times and to analyse the influence of heterogeneous factors. Finally, the power economic dispatch model has been used to simulate the effect of the charging time-of-use pricing on the cost and load of the regional power system. Policy recommendations are provided based on consumers' willingness to pay for charging at public charging stations and home chargers at different times on weekdays and weekends. The simulation shows that under the EV charging time-of-use price mechanism with a 50% price increase during peak hours and a 50% price reduction during valley hours, the total power cost of Beijing-West Inner Mongolia power systems is reduced by 302.3 million CNY compared with the current scenario. The average peak-valley difference of thermal power output can also be reduced by 11.7% on weekdays.