Changing From Wind to Solar Power - Question?

Dougal

Dougal

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Although where I keep the boat has reasonable winds, I've removed the Rutland913 and plan to use a couple of solar panels.

I know NOTHING about solar panels (yet). Do I need to buy marine specific items only?
 
Dougal said:
Although where I keep the boat has reasonable winds, I've removed the Rutland913 and plan to use a couple of solar panels.

I know NOTHING about solar panels (yet). Do I need to buy marine specific items only?
Click to expand...

Quick answer is no.

Lots of threads on the different types of solar panels: flexible, semi-flexible, monocrystaline and their pros and cons.

Lots of threads too on charging controllers. And the old perennial, how many panels do you need - those ones tend to lurk around the liveaboard forum.

In fact, if there was a way of harnessing power from forum threads on solar panels...
 
I suppose the first question would have to be about what your current (no pun) power demands are, after that you can start thinking about what (no pun again, I promise) you need.
 
We have 2 and I think Fascadale is correct. Do your power audit, then work out where you can put them and what sizes will fit. This will probably be your biggest limiter.
Try to use more than one, that way the inevitable shadows are less likely to hit both at once.
When fitting put some silicon grease on the wire joints or verdigris will bugger up the current flow. I've used expensive and I've used cheap and TBH I'd go for cheap every time, the outcome seems pretty much the same.
Regulator; try to get one that tells you what charge its putting in. Morningstar do several, their sunsaver duo lets you charge 2 battery banks and you can get an inexpensive plug in monitor.
My expensive one was a Sunware compact 60W and the cheap was from Pennygreenfingers (Titan)
http://www.marlec.co.uk/off-grid-products/solar-panels/sunware-solar-panels/
http://www.pennygreenfingers.net/60w80w100w-semi-flexible-solar-panels.aspx
http://www.marlec.co.uk/off-grid-pr...lar-controllers/morningstar-solar-regulators/
http://www.marlec.co.uk/off-grid-pr...lar-controllers/morningstar-solar-regulators/

No connection with any of the above, just used them. Marlec are very good with advice and after sales, I found.
 
Power audit first.

Remember that panels produce only about 50% of their wattage for about 6 hours, in summer.
The bigger the panel the more power it produces. Monocrystalline and polycrystalline are far more efficient than amorphous (flexible)
In terms of bang for buck you're best off buying a large domestic panel. These produce power @ up to 72volts http://www.kyocerasolar.eu/index/products.html
Most advertisers are agents - manufacturers are Solarex, Siemens in Europe, Kyocera in Japan and a host of small Chinese manufacturers.
Buying cheap PV panels is false economy - they last 3-5 years, the big producers guarantee output for 25.
I have bought Marlec amorphous semi-flexible, they're down to about 65% output after 5 years (good for cheap amorphous panels), whereas the 2 pairs of Kyocera I have are still putting out full power in fact the 100w KD panels, (if I remember to clean them) are better now than in 2009, when fitted.
If you relly want serious power you'll need an MPPT controller.
Suggest you PM Nostrodamus who has gone through the pain of learning about solar and has now got his desired set-up.

Mine is probably an extreme case, I live on the boat in the Med 6/12, usually @ anchor. My power budget is 50-80 AH (depends on temperature making the fridge compressor work harder and on how much I use the laptop).
I have 328w PV panels feeding 330AH of battery through a BZ500 MPPT controller - it means that I can lie @ anchor for 5-7 days without system volts dropping below 12.2v. And those panels are 2nd & 3rd generation and well obsolescent.

There are a lot of theorists out there, usually with obsolescent information, the pace of change in solar power is increasing - latest polycrystalline panels are 18-21% efficient - 10 years ago 8-9%, as the mix responds to wider and wider wavelengths.
The latest products are laid down on PET film (in production in Texas) and prototype work on 3 layer doping is nearly doubling (in lab) the current best panels.

Even in the windier parts of UK wind generation is fighting a losing battle - though the ideal set up IMHO is a balance of both, above 52 degrees. Here @ 35-40N solar is about 22% the capital cost of wind generation.
 
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sorry charles I have to disagree with the cheap option. I bought a cheap chinese panel some 8years ago and its still going strong. The time I bought mine the main manufacturers were over three times the price panel for panel, so if i have to replace next year i am still not out of pocket.
A close relative who worked at the Florida research centre two years ago said that funding is being pulled all over America, the Chinese are pouring funding into solar an battery development and attracting the best scientists aswell.


[/I]
charles_reed said:
Power audit first.

Remember that panels produce only about 50% of their wattage for about 6 hours, in summer.
The bigger the panel the more power it produces. Monocrystalline and polycrystalline are far more efficient than amorphous (flexible)
In terms of bang for buck you're best off buying a large domestic panel. These produce power @ up to 72volts http://www.kyocerasolar.eu/index/products.html
Most advertisers are agents - manufacturers are Solarex, Siemens in Europe, Kyocera in Japan and a host of small Chinese manufacturers.
Buying cheap PV panels is false economy - they last 3-5 years, the big producers guarantee output for 25.
I have bought Marlec amorphous semi-flexible, they're down to about 65% output after 5 years (good for cheap amorphous panels), whereas the 2 pairs of Kyocera I have are still putting out full power in fact the 100w KD panels, (if I remember to clean them) are better now than in 2009, when fitted.
If you relly want serious power you'll need an MPPT controller.
Suggest you PM Nostrodamus who has gone through the pain of learning about solar and has now got his desired set-up.

Mine is probably an extreme case, I live on the boat in the Med 6/12, usually @ anchor. My power budget is 50-80 AH (depends on temperature making the fridge compressor work harder and on how much I use the laptop).
I have 328w PV panels feeding 330AH of battery through a BZ500 MPPT controller - it means that I can lie @ anchor for 5-7 days without system volts dropping below 12.2v. And those panels are 2nd & 3rd generation and well obsolescent.

There are a lot of theorists out there, usually with obsolescent information, the pace of change in solar power is increasing - latest polycrystalline panels are 18-21% efficient - 10 years ago 8-9%, as the mix responds to wider and wider wavelengths.
The latest products are laid down on PET film (in production in Texas) and prototype work on 3 layer doping is nearly doubling (in lab) the current best panels.

Even in the windier parts of UK wind generation is fighting a losing battle - though the ideal set up IMHO is a balance of both, above 52 degrees. Here @ 35-40N solar is about 22% the capital cost of wind generation.
Click to expand...
 
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From solar thread on liveaboard, I suggested that:
First Q(s) to answer is where do you intend to fit them (two are more versatile than one) and what area (L and B) can you accommodate.
I would say that if you can accommodate higher wattage pannels than you calculate you require, it won't go amiss.
Solar o/p is seldom if ever its max rated, better to have spare capacity than insufficient.
 
In choosing to go solar for power on a boat along with the determination of how much current you need is the location and mounting of the panels. This will probably dictate how many watts you can fit. The normal location of the boat and particularly the orientation of the boat will dictate very much how much power you get. So a boat which is always moored in one direction can have the panels facing south at a suitable angle to give max power. While a boat on a swing mooring can end up facing any way so panels will probably be best horizontal but then a long way from facing the sun.
By comparison if it was solar for a holiday cottage then space is no problem and cost might be a factor.
So I think actual aesthetics and space will determine if you end up with solar that will simply keep a battery charged while you are away. You might be able to fit larger panels that will provide some or all of your power needs. If you are live aboard with no shore power then don't be too quick to get rid of the wind gen.
One point is that if you buy and fit a small panel and decide you casn fit and afford a bigger panel then they work quite well in parallel and whilst bigger means more watts per popund you won't be too far behind with smaller panels.
One good source if you have room is the domestic PV panels for houses. They tend to be around 200 watts @ 40 volts and are pretty big. You will need an MPPT controller that will happily take 40 v input to charge a 12v battery system. good luck olewill
 
I purchased one of these http://www.cleversolar.co.uk/shop/s...s/flexible-monocrystalline-solar-1094990.html for casual use last summer. IT really is quite flexible (at least 30 degrees) and with some shock cord attached sits nicely on the sprayhood or coach roof. I only went for the 60W for ease of storage below.

For 'real world' I did see >3.2A on a nice sunny day. Fed up with wind and the vibration issues but the Rutland/Marlec HRSi controller manages solar as well. The unit seemed to come from Germany and the supplier claimed that no blocking diodes were required due to the inherent high resistance, but I did fit one 'just in case'.
 
Has anyone got panels hung off the guardwires ? If so, do you remember which model/supplier you chose ? Am struggling to find one which is long but not too high. The maximum power is 50 watts as my Rutland regulator will only accept 100 watts.

Am also concerned about the weight as I am not sure if the top wire will be happy with 3 or 4kgs being hung off it. Do not want to stand it on its base as the idea is to angle it upwards/outwards when not sailing.

Finally, if anyone has gone down this route, are you happy with them or in hindsight would you do it differently ?
 
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