A Van de Graaff generator is an electrostatic generator which uses a moving belt to accumulate electric charge on a hollow metal globe on the top of an insulated column, creating very high electric potentials. It produces very high voltage direct current (DC) electricity at low current levels.
AGALABS Van de Graaff Generator is a standard apparatus for demonstrating the presence of static electricity. Overall, the concept of Van De Graaff Generator is very simple. A belt passes over two rollers, made of different materials (teflon and aluminum). Two metal combs are held near the belt surface and the lower roller is attached to the electronic motor. This device harnesses an effect called Electrostatic Induction in order to pump electrical charge. These electrical charges get accumulated on the surface of aluminum dome. As a result sparks are seen if the grounded aluminum sphere is brought near the dome, depicting the phenomenon of corona discharge.