Solar/Electric Powered MacGregor26

A forum for discussing boat or trailer repairs or modifications that you have made or are considering.
vincecate
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Solar/Electric Powered MacGregor26

Post by vincecate »

I have ordered a Minn Kota RT160EM which is a trolling motor that attaches to the outboard. This is 160 lbs thrust and should be fine in light winds. I will experiment to see how much wind I can handle. I am planning on having 4 big 6 volt batteries so that I can play around for an afternoon. This is probably about 400 lbs. I am thinking of just 2 solar panels of 170 watts each so it will charge up during the week and I can use it for an afternoon on the weekend.

The motor is 2784 watts so around 3.5 Hp.

These solar panels are 90 lbs each. I am wondering how many it would be reasonable to put on top. I have had a time where I had too many people up top (and maybe also too far forward) and the boat became hard to control while moving fast. With the electric motor I won't be going fast, so maybe this is not such an issue. Also, I won't be sailing, so maybe stability is not such an issue. Seems two panels at 180 lbs would be fine. Do you think putting 4 panels at 360 lbs or 6 at 540 lbs up on top would be ok? I could make power as fast as I was using it with 6 panels and 1/3 throttle.

Any other problems with this idea?

-- Vince
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BOAT
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Re: Solar/Electric Powered MacGregor26

Post by BOAT »

too much weight.
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Sumner
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Re: Solar/Electric Powered MacGregor26

Post by Sumner »

Wondering where you are going to put the panels. We have.....

Image

http://purplesagetradingpost.com/sumner ... de-33.html

....3 panels (200 watts) now and they take up a fair amount of space. If the panels are further forward and get shading from the mast, boom, sails or anything else they aren't going to put out much. I think even two 170 watt panels are going to take up quite a bit of room.

Since panels on a boat are never going to put out full rated wattage from personal experience and from others posting here is the formula I use to see on the average (good days and bad days) how many amp-hrs/day I can expect in a locale that gets better than average sunshine.

(((panel wattage)/12)*(6))/2 So a 170 watt panel might average about 40-45 amp-hrs/day. The formula is a little conservative, but I think pretty realistic in the real world. At least you are erring on the conservative side.

Our sailboat is already solar powered.........since the sun drives the planets weather and wind :wink: ,

Sum

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Boblee
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Re: Solar/Electric Powered MacGregor26

Post by Boblee »

Seems to be a lot of trouble for doubtful gains we just used our etec 50hp at av 1200rpm over approx 280k's for 40l of fuel and thats a lot of hours at 1200rpm.
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SKIPPER2C
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Re: Solar/Electric Powered MacGregor26

Post by SKIPPER2C »

I have 2 X 170 watt panels and the alternator connected to a Ctek D250S Dual Battery Charger and 4 x battery's and I have no power problems.I have all the the bells and whistle, Radar, Speed Instrument, Depth Instrument , fishfinder/sonar system ,auto pilot, LifeTag man overboard system, microwave ,2600 watt inverter , dvd player ,tv, FRIDGE, FREEZER, spotlights all over ,laptop, ACTV camera connected to the tv to sea before the boat while sailing. etc.
Can not believe the difference the D250s made. Is is the money well spend.

http://www.batterychargersdirect.com.au ... -dual.html

Renier
vincecate
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Re: Solar/Electric Powered MacGregor26

Post by vincecate »

Skipper2c: "I have 2 X 170 watt panels ..."

Where and how did you mount them?

I remembered reading a safety warning about having too much weight up high and just found it again (URL below). I had been thinking I could just partially fill the water ballast to compensate for the lead ballast I had from the batteries. This says that the water will slosh around and so make things unstable. Replacing the full weight of the water ballast with batteries might be more than I want to spend on batteries. Hum. Having an extra 400 lbs down low in the boat should not really be a problem, right? It is only how much weight in solar panels I have up high that hurts my stability, which is the real issue. Right?

I also wonder how water tight the opening is for letting water ballast in and out. If I have it closed to keep the water ballast tank empty I wonder if after a few hours moving slow with the electric motor there would be significant water sloshing around in the tank. So trying to keep the tank totally empty might be another problem.

http://www.macgregor26.com/safety/safety.htm

If I put a bunch of batteries and solar panels I am worried about how hard it will be to get the boat on or off the trailer. So my thinking was to load this weight on and off from the dock at the beginning and end of the summer and just leave the boat in the water (with undercoat) when loaded.

In the past when I have had the boat tied up at my mooring it sails back and forth or swings back and forth. Does anyone have a good way to deal with this? I am in the Caribbean (Anguilla) and the wind mostly comes from the East. I am thinking maybe a second mooring so the two lines would hold the front of the boat in one place. This means putting down a second mooring which is a bunch of work but as my old one is 6 years old it might be a good idea anyway.

I want to build a series of solar powered boats and putting solar on my MacGregor 26 is my way to get started and learning. I am going to put stuff at http://blog.floatingislands.com and http://floatingislands.com/ but not much there so far.

Thanks for the help,

-- Vince
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SKIPPER2C
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Re: Solar/Electric Powered MacGregor26

Post by SKIPPER2C »

I made a stainless frame for the panels. My boat is the king of heavy and no problem at all. I keep the water ballast full at all time when in the water.

Image

Image

Image

Renier
Last edited by kmclemore on Wed Feb 13, 2013 6:09 am, edited 1 time in total.
Reason: Fixed your picture links. (Yeah, I hate the new Photobucket, too!)
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JohnCFI
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Re: Solar/Electric Powered MacGregor26

Post by JohnCFI »

SKIPPER2C wrote:I made a stainless frame for the panels. My boat is the king of heavy and no problem at all. I keep the water ballast full at all time when in the water.
Renier
Just love what you have done at the stern, can you post some more detailed pictures (close-ups) and explain how it is all attached. Many thanks......
Boblee
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Re: Solar/Electric Powered MacGregor26

Post by Boblee »

Yes the Cteks are a great charger, the only reason for not buying one earlier was the price but now they are much cheaper and better.
Have several batteries here that were due to be thrown but they are now back in service.
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RobertB
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Re: Solar/Electric Powered MacGregor26

Post by RobertB »

Two questions:
How do you fish?
How do you trailer under a low overpass?
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SKIPPER2C
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Re: Solar/Electric Powered MacGregor26

Post by SKIPPER2C »

Two questions:
How do you fish?
1. In style. The black seats turns around.
How do you trailer under a low overpass?


2. Very carefully.

Just love what you have done at the stern, can you post some more detailed pictures (close-ups) and explain how it is all attached. Many thanks......
Will do so as soon as l take the pictures and sort the spelling out.
( On a new TOPIC.)

Renier
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Re: Solar/Electric Powered MacGregor26

Post by BOAT »

You don't look like Humphrey Bogart do you?
vincecate
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Re: Solar/Electric Powered MacGregor26

Post by vincecate »

So it turns out the 170 watt panels available on my island are actually only 35 lbs. So the weight is not nearly as bad as I thought. I may try to put on 3.

Does anyone think putting 400 or 500 lbs of batteries down low in the boat will be a problem?

Thanks for the pictures of how you guys mounted your solar panels!
bartmac
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Re: Solar/Electric Powered MacGregor26

Post by bartmac »

We have 2 186 Ah Geltech and 2 x 100 Ah Marine batteries (wet /lead)....not sure of weight but would go a bit less than what you propose.....fitted low they form part of ballast.Our ultimate aim would be to replace the 100Ah marine batteries with more geltechs but cost is currently not allowing this....I'd like to have the same type of batteries all around to simplify the charging system.Have found a supply of batteries second hand out of fire/security etc systems in high rise buildings....they need testing every 6 months and a big test every 2 years in Australia....some service people just replace after 2 years
vizwhiz
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Re: Solar/Electric Powered MacGregor26

Post by vizwhiz »

I'm still not sure I understand the reason for doing this - it seems to be a major complication, making the boat much more complex and loaded with infrastructure when the living space aboard is already limited...is this due to a significant limitation on gasoline? plans to get "off the grid" and not wanting to refuel for long periods of time? Or is there some other benefit to trading the already compact power/weight ratio of the gas motor for hundreds and hundreds of pounds of batteries and panels and wires and breakers and such? :?:

This is not meant to be critical, :) it is just difficult for me to understand the purpose behind it... In my head, it sounds like "should I jump off the skyscraper, or should I climb into the tiger's cage at the zoo?"...my thought is to wrinkle up my nose, raise my eyebrows, cock my head sideways and say "Why would you want to do either one?" :|

There may be a lot I missed...maybe another conversation already took place and I blinked? :D
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