Quote:
Originally Posted by irish1958
The only way one can get more distance out of battery propulsion than out of diesel propulsion is if the recharging of the batteries is a more efficient use of the diesel engine than using it for propulsion; and/or the propulsion of the boat by battery is more efficient than that of desiel. Is it?
When running on deisel only the speed is faster so the boat is using more energy per unit of distance to push the boat than the lower speed of the battery propulsion uses to push the boat.
You can test this: drive your car at 40 mph and check your fuel usage; now drive at 80 mph and recheck it.
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Not true. All motors, be they in cars or u-boats, have a optimum running speed. most cars run most efficiently at ~55mph.
A VIIC runs most efficiently at ~7knts on the surface.
It runs most efficiently below the surface at ~3.5knts, however this is less efficient than the surface speed of 3.5knts.
You only get out of the batterys as much as you put in the (minus the efficancy loss of the alternator and batterys)
It is impossible for the e-motors to improve efficancy |
