There are many factors that affect market penetration, such as. According to the 20 12 forecast of Parker Research Company, the number of rechargeable electric vehicles (PEV) in the United States will accelerate in the next few years, and will increase by 43% by 20 17, with an annual sales volume of nearly 360,000 vehicles. However, the popularity of different regions varies greatly. For example, California has a large population and PEV has the largest sales volume. However, as a percentage of total car sales, smaller states, such as Hawaii, are in the lead. Due to the highest gasoline price in this state, its PEV market penetration rate is the highest, which is expected to reach 6.3% by 20 17. California followed closely, accounting for 5.4%. It is considered that the market penetration rate of PEV is influenced not only by oil price, but also by population factors, user awareness, convenience of related infrastructure, power incentive policies of local power companies and other factors.