An environmental protective electrical power generating system is formed by a penstock connected at its opposite ends to a large sewer for conveying waste water from feeder pipelines to a sanitary treatment station. Sewer waste water is propelled through the sewer line by pumping equipment which simultaneously pulverizes most large objects carried by the waste water. The waste water is diverted, through a control gate, into the penstock where it flows through and operates one or more water-operated turbines. The turbines are operatively connected to electrical power generators for producing electrical power and dispersing the power through an electrical power transmission system. Depending upon the size of the sewer pipes, the volume of liquid flowing there-through, and the turbine and generator equipment, electrical power is generated without affecting the environment or ecology and without the use of fossil fuels.