Anonymous wrote:

As for panels I'm looking at 3-400W as well (can't reasonably fit much more on a small boat) but I might want to split it over two panels to minimize issues with shading. For charge controller I think I'm going with the Victron MPPT 100/20. Not sure from where I'll buy these yet, gonna shop around for good deals when it's time to pull the trigger (soon, once I get home to Finland).

Interesting, Oscar! You're going for the Haswing Protruar 5.0 too? Is your source for the solar panel and controller the same as mine?

I wasn't aware of the Haswing at all but it looks like a solid choice, so yes, probably. :) Haven't really crystallized my plans in terms of brands/models/vendors just yet. I had been looking at a Caroute N300 (which was what initially triggered the idea of using an electric outboard) and it's quite similar in specs - 24V, 160 lbs thrust, 2.5kW. Managed to get as far as finding an Ebay seller that ships to Finland, but the Haswing actually seems like a much better choice since it's a) considerably cheaper and it's b) from an established brand so there would be a lot less hassle with warranty and parts (if needed).

As for panels I'm looking at 3-400W as well (can't reasonably fit much more on a small boat) but I might want to split it over two panels to minimize issues with shading. For charge controller I think I'm going with the Victron MPPT 100/20. Not sure from where I'll buy these yet, gonna shop around for good deals when it's time to pull the trigger (soon, once I get home to Finland).

Anonymous wrote:

Sounds almost excactly like the plan I’ve had in mind in case some kind of surpirise funding would suddenly appear. The Haswing has changed the situation a lot more appealing.

Haha yes, in fact I had decided on pretty much this exact setup a couple of days before this post. I'm very glad to see David having arrived at the same conclusions. I will be building the battery myself out of individual cells though and might up the capacity to 200 Ah but other than that the setup looks more or less identical.

Darren, great idea regarding the boost charge controller, it would enable me to use the 12V wind generator that I already have.

Anonymous wrote:

Darren wrote:

The oceanvolt looks marvellous, although the price must be shocking.  I was going to go considerably lower tech.  My take on hydro or wind is that they both don't produce much power at low velocity, so you might as well just optimise them for higher velocity.  Low tech hydro would be a towed version similar to a Hamilton Ferris or Ampair.  For coastal cruising it would seem like something like a WattandSea might be more useful in that it would be easier to kick up and put down. 

I'm not so sure about the Oceanvolt: it only starts charging at 4 knots - useless for a smaller boat.  I remember seeing the Hamilton Ferris on a boat in 1983 when we had an Ampair. I recognised it straight away when I followed the link, although I've never seen one since.  Out of curiosity, I have asked for more info.  We could hardly believe the owner of the one that we saw, when he told us about its output: as I recall, it was 3 or 4 times that of the Ampair and started putting out a noticeable charge at 3 knots.  Of course, in those days, we weren't quite so greedy and were more than happy to have something that would give us 2 or 3 amps.  WattandSea are also irritatingly reluctant to offer some figures on their site.  I suppose they would respond to an email, but somehow I think this is another charger that is aimed towards bigger boats that anyway motor when the speed falls below 4 knots.

I have had experience with a Ham Ferris water charger on one of my earlier off shore cruising yachts which was a Searunner trimaran. From memory the unit put out a very high rate of charge when used on a passage, so much that the inline blocking diode got too hot to touch. There was a problem though with the speed of the trimaran which was usually in the 6 to 9 knot range and so the towed propeller would skim pacross the surface of the water and tangle the tow line so I eventually stopped using the charger. But I think on a slower boat the charger would work well and still put out a useful amperage in the 4 to 6 knot speed range.

I am still a fan of solar panels and a smaller multiblade wind generator  such as the English Rutland units as a charging system for a cruising yacht. The key though to any charging system is minimising power requirements. LED lighting, electric refrigeration with a well insulated box, and minimising other electronic toys. I have been pleasantly surprised how well my 120 watts of solar panels with an MPPT solar controller more than meets our electricity needs on our current yacht which includes refrigeration  pressure water pump, LED lighting, and charging of phones, iPads, bluetooth speaker, and running a simple chart plotter.

Anonymous wrote:

£82.29 for a crimping tool?! Phew! There are, indeed, more affordable ones to be found on eBay.

But I already have a hydraulic press, for sail grommets. I might try a bit of DIY tool-making. It seems to be very simple to rig up something like this, using a V block and a pointed pin.

I should of said I linked to that tool just because it looks to be the exact one I have, which cost about $50Cdn (£30) on sale at a local tool store.  Prices on Amazon seem to cover a wild range.  Most of the hydraulic crimpers on Amazon come with metric dies which don't match the imperial fittings we use here in Canada or the US, otherwise I think I'd like one of those hydraulic crimpers.

I used to solder exclusively, but now crimp almost all the time.  I think crimps are better (faster, joint is mechanically fastened, easier to work in cramped quarters, you don't have a stress riser at the transition of rigid solder to flexible wire).  The only part that is harder with crimping is paying for the tool upfront.  However, there are a lot of tools that are sufficiently inexpensive now that they quickly pay for themselves.

Crimps work best if you use matched crimps and tools.  This isn't the least expensive way to go.  However, if you can match the mechanical strength in this table, then you should also have an excellent electrical connection.  This article describes the details better than I can.  I don't follow his guidelines exactly, but I do test my tools and crimps to make sure I'm making reliable low-resistance connections.  I have a ratchet crimper and the dimple crimper described above for larger terminals.  I use both with inexpensive uninsulated terminals that I cover with glue-lined heatshrink.  I've checked the results from both tools and they are able to pass the mil-spec rating in the table mentioned above.

Some time ago I came across some stats about boat fires/explosions.  Electrical fires were far more common in causing loss of the boat than propane explosions.  I suspect many folks worry about or don't have propane aboard, yet don't give a lot of attention to their electrical connections.