Turbochargers with variable turbine geometry change the output of the turbine as a function of engine load. In this way the optimum boost pressure can be maintained and optimum use can be made of the energy in the exhaust gas. Cross-sectional changes are made by resetting the turbine blades (smaller contact surface at low speeds, larger contact surface at high speeds). VTG turbochargers are particularly efficient at partial load and eliminate “turbo lag”. They increase engine power, increase throttle response and can also have a beneficial effect on particulate emissions. In addition, they open new perspectives regarding the control of exhaust gas recirculation.