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Firstly, is there such a thing? I hope to do the wiring soon as the boat approaches its launch date.I plan to use two 6volt trojan batteries to power the basic requirements at the moment and will at a later stage add more power/storage with additional solar and batteries. i would like to power the following initially;

led nav lights

cabin lights




I have two small solar panels that are rated at 20 watt ea. This is hardly enough to recharge the batteries but will have to do for now.i hope to install more solar to about 200 watt eventually for extended voyaging.I plan to wire the boat so the additional kit will be able to be in place with not much more work.

your thoughts and ideas will be appreciated.

all the best


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Sorry I have to disagree with that, Lloyds, DNV etc state that if you must use solder, that the joint has to be crimped first. Mechanical joints (crimp or clamp) are preferred to solder for several reasons.

I've worked in the marine, space and nuclear industries for 20+ years, all use crimps.

Lee Dilkes said:

Learn to solder guys & gals it creates a far superior join every time.

Ahhh whoops my bad! Seems I have been given the wrong advice.

Belt and suspenders.  Why not do both?  By the way, Nev did know about the trick if the shrink sleeve with the glue inside.  He gets around.

Yeah I was blown away when I saw that... Glad you liked it and hope it helps :)

paul anderson said:

Excellent,this may be the way to go for puters on my boat without having to upgrade the whole system.i like this very much.

thanks Brandon.

I think I'll be starting out with the Nomad 7 setup on element just for a trial run and because I can use it for backpacking and many other applications and its cheap ($80 usd) then once it's been proven at sea I'll upgrade to the Sherpa 50 or Sherpa 120 and call it done. Even those are backpack-able!!  I mean what more could you ask of a power system It's light, portable, efficient, and all works well together easily... It just makes a lot of sense on a Wharram especially a smaller one. 

Brandon,i think this may be the way of the future for many applications, these guys will probably do well out of Sandy as people wake up to the fact that the power sometimes is off for more  than a couple of days.Please let us know how you go with this set up, i am sure many of us would be interested .

all the best


mgtdOcean said:

Doesn't one of your pics show a mount for an autohelm? That little sucker can eat some Ah . I think for trailer boat designing the port/std wiring to have minimal cross wiring is a big plus. Also I'd add a charger for those days you cab run a cord to a shore side plug.

You are right there about the autohelm mate, my thinking is first to get the boat in the water with the basic electric set up. Play with  the windvane first so that it is set and working. At a later stage i will add another battery dedicated to just the autohelm, with it's own panels etc or add the battery to the house bank, not sure yet.

You might consider using a tiny tiller pilot to operate a trim tab you could "Wharram stitch" on to the aft edge of the tillers with a tiny crossbar to operate them together.  You could re-fashion the designed rudders to make their trailing edge straight in stead of with that angle and that way the trim tab would work ok.  Those tiny tiller pilots use very little electricity.  We have one on Peace IV that operates an air paddle for our Monitor Wind Vane because Peace accelerates and decelerates so much the Monitor gets confused.  The tiller pilot keeps a compass course which is better for us.  The Monitor would be too heavy for a little boat, but there used to be a light weight Navik vane that would be maybe ok for the 26 or the 30.  Rory had a self steering system on his 21 that went around the world and twice across the Atlantic but I don't remember what it was.  Rory, are you still around here?  Comments please! 

I am endlessly facinated by all self steering set ups.    Ann

Pretty much what i have done Ann except I have not modified the rudder.


A Happy and sunny New Year to you from the wet and windy North.

I have been crunching the figures in this also as I want to use the laptop on board. Laptops use a fair bit of elec.

DISCLAIMER - This is based on research not experience.

From your list [very like mine] Nav Lt all night = 1ah. Cabin Lt less but say another 1 ah. Fishfinder i dont know but laptop 1 hour = 4ah. VHF receive very little, broadcast {25watt] 30 min = 1ah.  Spotlight [car halogen bulb] 50 watt but say Led alternative 5 watt 1 hour use 0.5 ah. Add up and round up =8 ah per day. Some elastic here already - how often will you run your Nav Lts all night / etc...Still we must start somewhere so 8 ah / day is the drawdown.

BEST CASE for panels is about 0.4 ah per watt of panel per day. So best case for 40 watt panel  approx 16 ah /day. Engineers often use half this output when designing systems so 8 ah reliable. 12 would not be unreasonable as a summer average perhaps. So you are spot-on with your 2 x 20 watt panels.

The recommendation for storage is usually output x 3. So say a battery of 30 ah. This will give 10 ah of power without stress.

So worth looking now at what we have with 40 watt panel and 30ah battery. First off there is enough in reserve to run for a day without any charge. For occasional heavy use we can draw maybe 20 ah in a day. This will use up both the incoming panel charge and the battery reserve. This is 250% the designed daily load. Of course you must use very little next day if you want to top the battery back up.

So weekenders should spend on batteries to store all that elec. generated on weekdays but liveaboards should invest in panels for constant supply.

There is a seperate case to be made for a minimum of 80/100 ah battery as this will allow you to run domestic power-tools of 500 watts or so for an hour with an inverter - very handy at fitting out or small repairs.

DISCLAIMER AGAIN..but I am going with 40 watt panel and big battery. And a Prayer To St. Patrick..

And that bastard Murphy! Thanks mate for your valuable input to this discussion. I am sure it will be helpful to others as well. In a lot of ways i think we are on the brink of new tech for power supply, almost like the beginning of the steam age when it's true potential to humankind had not been fully understood or realized.

On the weather front of here just to be smug, it was 32 degrees c with humidity.

Enjoy the craic

all the best paul.

I got the Guide 10 Adventure Kit from Goal Zero for Christmas. It came with The Nomad 7 panel and the Guide 10 battery pack/ charger. The quality is great and the panel charges my cell phone in abt 2 hrs. The Guide 10 battery pack takes abt 4hrs to charge from the panel and holds 4 AA batteries. The charged battery pack will charge my phone almost 3 times before needing to be recharged. I imagine the same would be true for a handheld gps or vhf.  A big plus for me is my navigation lights and fans on board are powered by AA batteries so I can use this to recharge them over and over while sailing. I've already sourced some of the best rechargeable AA's on the market and they aren't too bad. While this setup will be ideal for my Tiki 21 I imagine it would be a bit lightweight for a T26 or T30. So I only add this for any small Tiki owners who may be reading and to say that the quality from this company seems to be top notch and the products meet or exceed the advertising. (Which can be rare) Also the larger kits they offer while they my be expensive keep in mind that in most cases the battery is a lithium ion and will out last and out perform any AGM or lead acid equivalent. Just food for thought :)

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