Originally Posted by K1W1
NYCAP- I am pretty sure I have seen a few cruising sailboats with an alternator that is driven by a towed prop. These are used to charge batteries which I assume also provide lights.
I have not seen this on any motoryachts. Anything you tow that takes power to turn it will be costing you fuel, there is no such thing as free power, even the sailboats pay a bit in speed loss but as their fuel is free when sailing they are the best placed to take advantage of this type of thing.
There is no reason why you couldn't use a wind generator on a motoryacht I am not sure of the overall savings thugh when you consider the cost of the equipment and the fuel to haul it around whether used or not. It would give you some battery charging at anchor without running ya genset or main engine to provide the same.
There are well known ways of harvesting the waste heat from engines and exhausts but these are generally for heating feed water etc and are not widely if at all used to provide electricity. Most of these are in use on ships that are underway for days on end so the operation of these can stabilise.
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Thank you K1W1. Your 1st sentance was exactly the answer I was looking for. I'm quite aware of the limitations for wind generation, and suspected the same for water however I had not heard of anyone trying it (such as "an alternator that is driven by a towed prop"). As stated in the original post it was just idle curiosity.
"Mellowed with age" NYCAP