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post #2 of Old 01-19-2002
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Electric propulsion

I have a little experience with electric aux. power having spent a few days messing about on a little gaff rigger with an electric system. Here are my initial conclusions.

Electric works best simple boats and for daysailer/overnighters. There really is a limited amount of electrical storage capacity so you don''t have the reserves to operate refrigeration or an autopilot, or some of the complicated electronic systems that have become so popular. You lack the kind of reserves to run navigation lights for several nights in a row. You lack sufficient reserves to motor upwind for a six or eight hours straight without either having a huge battery system or else spending a 8 to 10 hours on a charger. (I understand that you can charge faster than that but it shortens the life of the batteries dramatically.)

Most electrics lack the solar and wind generator capacity to regenerate solely from the charger systems on board. That means that longer cruises require time spent at a dock hooked to a charger. On some of my favorite cruises we put into a dock for less than an hour in an entire week. As most electric auxilaries are configured that simply is not possible. Of course it is posible to add solar cells and wind generators to replace daily losses expecially if you lived somewhere like teh Carribean where there are reliable winds and sunshine so you motor less and recharge more. Electric auxiliares at thier worst somewhere like the Chesapeake, where our winds are unreliable, and our sunlight levels are compromised by haze.

It is most ideal to keep an electric at a dock with adequate charger capacity rather than on a less expensive mooring. If you keep an electric on a mooring you need to be able to get aboard and maintain the system.

Electric works best in a boat that started life designed to have an electric auxiliary. The batteries and drive motor are quite large and outrageously heavy in proportion to the size of the boat (about 50% heavier than an equal power diesel engine, associated gear, and fuel tank) so careful placement is critical.

The electrical motors is wonderfully available and quiet. So if you try to sail into the dock and end up too fast or slow, you throw a switch and have instant brakes or a little extra push. They are not nearly silent but so much quieter than a diesel that it really is wonderfully nicer to use the motor.

The batteries eat up a lot of useable storage space. If you used normal wet batteries you need to have them in an easily accessible, vented locker. You have a lot of maintenance keeping the cells properly filled with distilled water. If you have sealed cells you have a much more expensive system with less capacity per pound and supposedly a much shorter battery life. Either way, it is my understanding from the discussion between people who actually had electric drive systems and which took place at a lecture that I attended on electric drive systems, neither system has the kind of 80k-100k hrs
maintenance-free reliability that you are suggesting.

Lastly, the Albin Ballads are wonderful boats. They sail well and are a joy to the eye. BUT they are not commodious and do not tollerate a lot of weight. I would think that they would be a very poor candidate for an Electric aux system. I would think that you could rebuild the existing Volvo or replace it with a small Yanmar for a fraction of the cost of the electrical aux system. You would end up with a boat with a bigger resale market and one that is easier to keep up.


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