Abstract New technologies that can scavenge ambient environmental energy have attracted increasing interest in the past decades. Recently, triboelectric nanogenerators (TENGs) have been demonstrated as a powerful approach for harvesting various forms of mechanical energies. In this work, a newly designed TENG is demonstrated by coaxially integrating multiple layers disk TENGs into a whole system, which transforms the fluid flow into a rotation motion of multiple layers disks and generates a multiplied electrical output. To achieve the effective structural integration and output multiplication, a D-shape shaft is adopted to facilitate the synchronized relative rotation of all the segmentally-structured disk layers and light weight and low stiffness springs are employed to ensure the intimate contact of the tribo-surfaces. With the above design, the nanogenerator delivers an open-circuit voltage up to ~470V and a short-circuit current density of 90.6mA/m2, corresponding to an instantaneous maximum power density of 42.6W/m2 (2.68kW/m3) at a rotation speed of 1000rpm. By combining the TENG with a water turbine, the device can be effectively driven by a water flow from a common household faucet. This technology represents an important advance of TENGs toward practical applications and shows great potential in hydroelectric power and wind power industries.