China's urban EV ultra-fast charging distorts regulated price signals and elevates risk to grid stability

The wide adoption of electric vehicles is driving the rapid deployment of ultra-fast charging stations, particularly in China. This study uses simulations based on extensive real-world charging data from major Chinese cities and finds that deploying 2000 ultra-fast charging stations in a city may increase the peak-to-valley differences of the public charging load by up to 31.61% daily relative to baseline cases. While integrating energy storage systems can help smooth short-term load volatility, it may simultaneously exacerbate short-term demand surges, particularly during the transition from high- to low-price periods. Under an unregulated scenario, large-scale deployment of ultra-fast charging stations with energy storage could raise peak loads by over 70-85% by 2030 and multiply them by up to 7.5 times by 2050. These findings underscore that a comprehensive rethinking of grid management strategies and market frameworks will be essential to ensure urban energy resilience in an era of rapid electric vehicle expansion.