Shaft Power Meter

A shaft power meter measures the torque and rotational speed of the propeller shaft to compute delivered power, P = 2pin*Q, using strain-gauge torsion sensors or optical/magnetic phase-shift methods on the intermediate shaft. It is the primary instrument for verifying engine power limitation under EEXI (shaft power limitation, ShaPoLi) and for fuel-efficiency, CII, and hull-performance work, since shaft power tied to speed and fuel exposes hull and propeller fouling. IMO MEPC.1/Circ.815 and class guidance cover ShaPoLi monitoring; Kyma and similar makers supply certified meters used in EEXI technical files.