A computationally simple method for induced electric fields near subsea HVDC cables

A simple method has been described to calculate the total steady electric field induced due to the steady geomagnetic field, two subsea high voltage direct current (HVDC) cables and the horizontal motion of electrically conducting water (with an arbitrary velocity profile near the ocean-sea bed interface). This method has two advantages over the most recently published method. First, it does not require the use of complex three-dimensional numerical methods accessible only by licensing expensive commercial software. Second, it does not require modeling the entire column of water from seabed to water/air interface. For typical parameters, the perturbation in the induced fields due to the HVDC cables are in the order of 0.05 mV/m and extend to a distance roughly 10 times the cable spacing from the center between the cables. These perturbations in the field are strong enough to be detected by (at least some) marine organisms. However, it is not known if the effect is responsible for any behavioral or biological changes in these organisms.