Keith, Mark Stafford always appreciating your real-world numbers. Your almost 100watts regen @ 6knots.... what prop size/pitch? 12x8? The other problem with regen: most props are optimized for propulsion, not for braking.
Great traction analogy with golf-cart wheels vs propellers.
Mark Stafford
--- In electricboats@
>
> Most of the systems in use are in fact derived from golf-cart parts. But we typically use more efficient PM (permanent magnet) motors instead of the older series wound motors common in the used market. So it definitely can be done and I think a few on this board have examples. The drive and controller are only about 1/4 the total cost of a system so it's not really a great place to skimp.
>
> As for regeneration - it's one of those things that sounds great in theory but isn't really practical. Consider that all 4 tires on a golf cart are gripping the road with several thousand pounds of stopping friction - vs all that water easily slipping by a very small prop.
>
> So golf-carts get great braking, and a few watts of power - on a boat you just get more expensive electronics. I have a system that can regen and I get less than 100watts sailing at 6knots and then only when I carefully feather the controller (though I think the controller can be programmed to do this better). It's not impossible to boost this, but it's a science experiment, not a proven tech.
>
> Regards,
>
> -Keith
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