What is what does regen mean?

Regen is a term commonly used in the automotive industry to refer to regenerative braking. Regenerative braking is the process by which kinetic energy is captured and converted into electrical energy, which is then stored in a battery for later use. This is accomplished by using an electric motor to slow down the vehicle during braking, allowing the energy generated by the momentum of the vehicle to be captured and converted into electrical energy. Regenerative braking is a key feature of electric and hybrid vehicles, as it helps to reduce energy consumption and increase overall efficiency.