Trailing Generator - What a Beauty!

by Nancy Knudsen on 11 Jun 2008 Power generation is always a vexed question on a yacht – how much do you need? How will you generate that need? The modern sailing boat needs power – that is, if you want electronic instruments, computers, autopilots, as well as those items of personal comfort, refrigerators, deep freezes or microwaves.

Starting the engine every day to generate this power is a simple solution, as more systems means more complexity, and that means more stuff to break down or otherwise ‘go wrong’. We have one cruising friend who has lived and worked on his boat for 27 years, and starts the motor every day, rather than have to cope with the irritation of complex systems that can cause him times of grief.

However, fuel today is not only environmentally harmful but also expensive and getting more and more expensive. The wind and the sun are more and more being exploited by governments of the world in an effort to cut the use of depleting reserves of ecologically harmful fuels, and the cruising sailor need to take this 'on-board' as well.
If you haven't experienced trailing generators and how they work, now's the time to try them. You may hear that they are likely to be taken by a fish, which seems to have been the case when they were silver in colour, and resembled a fish travelling through the water.

However, the modern trailing generators are black, and probably invisible to fish. After 35,000 miles of cruising, with a spare in the hold (just in case), we have never had even a nibble, let alone a bite from a fish on our trailing genny.

The brand we use is an AMPAIR, and it puts in 6 amps at 6 knots reliably over a 24 hour period, though I am sure other brands may be just as successful. Unlike other natural means of power generation – ie. wind and solar - it doesn't care whether the sun is shining, and you don't need 20 knots of wind to make it effective.

It really is the simplest device in the world, consisting of a small generator attached to the stern of the boat, thirty metres of line, then the spinner, or propeller, at the end....and yes, you lose about .25 of a knot in speed. If you care about that, you'd better stick to racing!

(There is an option to have a 'double-use' product, usable as a wind generator or as a trailing generator, but mostly we have found we are using both constantly)

There are a couple of things to be careful of : The first piece of advice is to wear a pair of gardening gloves and let the line out somewhat slowly, as the impact load is huge when it reaches the limit of the line.

The other one is hilarious the first time it happens. If you forget you are in shallow water, and there's only a slight breeze, you may very well find you start sailing round in circles, anchored by the trailing generator to the bottom!

You'll find the product on Ampair's website, and they have world wide distributors..