No, a world-circling river would not flow of itself under known physics, simply because it went all the way around a planet. (Conservation of energy, ditto Green's Theorem re closed-path integrals.) So putting turbines in it wouldn't produce free power. Sorry, this won't work unless your world has some premise or other handwavium for inducing the water to flow. BTW, the Riverworld Series by Farmer has something similar, but it's clearly artificially powered (via alien tech far, far about our current level.)

Qualification: There are current loops in our oceans, such as the one circling Antarctica. One could in principle get power out of currents like those with turbines or similar, but the energy is coming either from the sun's fusion reactions or radioactive decay, however indirectly. No perpetual motion involved.

No, a world-circling river would not flow of itself under known physics, simply because it went all the way around a planet. (Conservation of energy, ditto Green's Theorem re closed-path integrals.) So putting turbines in it wouldn't produce free power. Sorry, this won't work unless your world has some premise or other handwavium for inducing the water to flow. BTW, the Riverworld Series by Farmer has something similar, but it's clearly artificially powered (via alien tech far, far above our current level.)

Qualification: There are current loops in our oceans, such as the one circling Antarctica. One could in principle get power out of currents like those with turbines or similar, but the energy is coming either from the sun's fusion reactions or radioactive decay, however indirectly. No perpetual motion involved.

No, a world-circling river would not flow of itself under known physics, simply because it went all the way around a planet. (Conservation of energy, ditto Green's Theorem re closed-path integrals.) So putting turbines in it wouldn't produce free power. Sorry, this won't work unless your world has some premise or other handwavium for inducing the water to flow. BTW, the Riverworld Series by Farmer has something similar, but it's clearly artificially powered (via alien tech far, far about our current level.)

No, a world-circling river would not flow of itself under known physics, simply because it went all the way around a planet. (Conservation of energy, ditto Green's Theorem re closed-path integrals.) So putting turbines in it wouldn't produce free power. Sorry, this won't work unless your world has some premise or other handwavium for inducing the water to flow. BTW, the Riverworld Series by Farmer has something similar, but it's clearly artificially powered (via alien tech far, far about our current level.)

Qualification: There are current loops in our oceans, such as the one circling Antarctica. One could in principle get power out of currents like those with turbines or similar, but the energy is coming either from the sun's fusion reactions or radioactive decay, however indirectly. No perpetual motion involved.