A system is described, in particular for cleaning, comprising: at least one high-pressure pumping unit (1) adapted to pump water or other similar fluids with a high output pressure; at least one electric motor (3) connected to the high-pressure pump (1) for its actuation; and at least one device (5) for regulating the revolutions of the pump (1), connected to the motor (3) for its control and for regulating the pump (1) so that it delivers high- pressure water, preferably from 500 to 2500 bar, and a very low flow-rate, preferably from 2 to 4 l/min.