Driven by the “dual-carbon” goals, new energy power generation is gradually dominant, yet distributed energy’s intermittency and volatility challenges power system operation. Focusing on potential flexible resources in power systems and large-scale grid connection of new energy vehicles (EVs), this paper innovatively introduces EVs penetration rate and the weight coefficient for encouraging new energy power generation, and constructs a virtual power plants (VPP) optimal scheduling model considering such penetration rate and flexible electrical and thermal loads. To achieve coordinated optimization of flexible loads on both supply and user sides, with the goal of reducing the total operating cost of the VPP, an electrical load model with load shifting, transfer, and reduction functions is built. Case studies analyze the impact of different EVs penetration rates on its optimal dispatching, verified by multiple scenario comparisons. The research results show that as the penetration rate of EVs increases to 50%, the total operating cost of the VPP continues to decrease, with new energy output increasing by 9.2% and gas turbine output decreasing by 15.4%. This reduces reliance on traditional fossil fuels and accelerates the green and low-carbon transformation of energy systems, but also strengthens the substitution effect of new energy power generation for traditional energy-based power generation.