There is no one answer to this question, as it depends on a number of factors, including technological advancement, cost, and public perception.
Electric vehicles have many advantages over gas vehicles, including lower emissions and lower operating costs.
However, there are still some challenges that need to be overcome before electric vehicles can completely replace gas vehicles. One of the biggest challenges is the cost of electric vehicles, which is still higher than the cost of gas vehicles.
Public perception is also a major factor, as many people are reluctant to switch to a new technology. However, as electric vehicles become more popular, this perception is likely to change.
So it's difficult to say exactly when electric vehicles will replace gas vehicles, but it's clear that they are the future of transportation.