Solar system???

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Great posts!!

There are PNW members here that espouse "solar will never work here and it is ridiculous to even contemplate" in just about every single other thread where solar panels have been discussed. Interesting to see hard data from someone who thankfully thinks outside of that box.
 
You are welcome for the data - I was sooo frustrated when I started things out not being able to find solid answers, I made a vow to collect real info and share it.

Now, I think the one thing that surprised me the most was how close our actuals tracked with the predicted. I went about predictions the hard way, and then found this tool: PVWatts Calculator

It is designed for land installs, but with some simple tricks can be used to product very accurate results for a marine/boat install as well. For fun, I used this tool just now - and looked at the differences between Friday Harbor up in the PNW, and Key Largo, down in the Sunshine State. Here is what I got for our 480W/12v system:

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Kind of interesting to see that during the peak 'cruising' months predict more out of our Solar Panels up North then in Florida! Because the modeler uses actual data as its input (you pick a reference point to use), it can make adjustments not only for latitude, but also typical cloud cover.

I have some more details about this tool, and how to make adjustments for 'marine' use here: mv.VikingStar: Solar Panels on the Boat - Modeling and Performance

And before folks start abandoning Florida for the sunnier PNW, better remind folks about all the floating debris/logs waiting to hole your hull - Mosquitoes with first and last names, and what every I can come up with :socool:
Boy, you can see the longer days for the PNW in those stats. It looks like my rule of thumb of 3.5 x wattage of the panels for daily production in our area during the cruising season is not far off....
 
On a different twist for solar, has anyone constructed a solar arhray above their flybridge bimini ? This appears to my largest unobstructed area. Large enough to support four 250 watt panels if needed. Attempting to determine my system requirements and any requirement to reconfigure my existing battery / charging configuration. I've seen a lot of panels laid out over the hardtop or in front of the flybridge. On sailboats I have seen smaller systems over the biminis but not sure if the weight of that many panels would be a problem with high winds ?

To me this seems like a win/win. The panels above the bimini, should make the flybridge cooler by absorbing the heat and protect and canvas below it. Interested in any feedback. My current house batteries are four 8D AGM and 4 GLT-6CT AGM. They seems to supporting the demand fine.

Thanks in advance for any recomedations
 
On a different twist for solar, has anyone constructed a solar array above their flybridge bimini ?
Rebel (John), occasional poster,did exactly that. Works fine, I believe holes were made and reinforced in the bimini canvas for the bolts securing the panels.
Sailboats with no bimini often fit a full width ss "square arch" carrying panels, at the stern.
 
As Bruce has written I placed 3x130w panels above my canvas bimini, I constructed an aluminum frame to support the panels bolted through the bimini frame. As Peter B commented at the time I was doing this, watch for chafing between the canvas and the frame. I added some rubber strip between the frame and the canvas at the fixing points. This system has been in place for about two and a half years now and so far so good. The pictures are not that clear I know but if you look carefully you will see some of the frame in my avatar. I guess the other aspect to watch out for is the size of your bimini frame. Mine is a solid one and a half inch s/s with strong attachments to the flybridge. I found a picture that is as close as I can get.

John
 

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2500 watt system on woman2blame

I will take pics but I have a 2500 watt solar set up, 24 volt with 800 amp/hr batt. System.Just got back from 3 months in exumas , Here's how it washed out. First off equipment, Full size frig. , freezer , sat tv system with 3 boxes and 3 big screens, dish washer, 40 amp batt. Charger for house bank. , micro / convection oven, 110 v head hunter pump for heads and fresh water, led bulbs in all 12 v lights, coffee pot, 2 lap tops and wifi modem , stereo sys. And misc. chargers. My gen is 15 kW and burns 1 gal / hr , I ran gen 2 hrs a day to make 60 gals of water each day. We watched 2 tvs approx 4 hrs each nite, frig runs 24 hrs . We anchored out every night so 22 hrs times 90 days = 1980 hrs gen didn't have to run equals 1980 hrs times 1 gal = 1980 gals times $4.00 per gal equals $7920.00 and govt. gave me 33% off taxes on a system that cost me $11,000.00 . I will show pics if anyone is interested.Plus my gen will last a lot longer and don't have to factor in replacing .And no noise.
 
Pics? You bet!! Sounds like the perfect balance to give you just what you need on the hook! If I could scale that system to about 1/4 size, it might be just perfect for my little 34 footer.

I recently completed all the electrical mods needed to allow me extended days on anchor. With all the conveniences of home - except washer and dryer - 2 small fridge/freezers instead of one big one, LED lights throughout, 12V 660AH house bank, 55A charger, Honda generator, Balmar 120A alternator, battery monitor, Wifi extender and router, 8-speaker stereo system, microwave, Keurig and Mr. Coffee, 12V HDTV, propane stove and grill and only a 1000W inverter. I need to run the Honda about 4 hrs/day to keep up with demand at a fuel burn of less than a gallon per day.

So generator operating cost is not a big issue but noise can be a problem in a crowded anchorage. I recently spent two weeks on the hook and little of that was in the company of other non-friend's boats, but free (after purchase) and silent is a good thing. I'm considering adding a cockpit cover to my boat....maybe solar panels would make a good addition as a cover in lieu of canvas.

What's the estimated longevity of today's panels? Aside from keeping them clean, is there any routine maintenance required to keep them producing efficiently? Do solar panels degrade over time and eventually become inefficient?

I hear the cost of panels has dropped considerably. I'm thinking a 600-800W system might fit my boat well to realistically restore the 175-185 AH needed, but I might only have room for 400-500W. Shadowing would be an issue in the cockpit aft of the FB and radar mast.
 
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Yeah!! I sure want to know everything you did for that system. I don't plan on 2500 watts, but 12-1500 for sure. My needs are much less than those you report.
 
..free (after purchase) and silent is a good thing. I'm considering adding a cockpit cover to my boat....maybe solar panels would make a good addition as a cover in lieu of canvas...

What's the estimated longevity of today's panels? Aside from keeping them clean, is there any routine maintenance required to keep them producing efficiently? Do solar panels degrade over time and eventually become inefficient?

...I hear the cost of panels has dropped considerably. I'm thinking a 600-800W system might fit my boat well to realistically restore the 175-185 AH needed, but I might only have room for 400-500W. Shadowing would be an issue in the cockpit aft of the FB and radar mast.
Al, barring some very clever fitting, panels won`t replace canvas, but they can afford some shade. Sailboats, lacking good places for panels, often construct a ss "square arch" just in from the transom to carry panels.
Most panels come with a 20-25 year guarantee of output, but finding the maker/seller to call on it might be tough. They don`t need maintenance, but the wiring/connections to the controller and to the batts, and any direct run equipment, might.
As to cost,panels do get cheaper. Most are from China, I think monocrystalline types are/were well regarded. I don`t worry about brand. I bought on Ebay, many do, the quality of framing may be indicative. You can get controllers on Ebay too, MPPT are the newest/best to get max out of the panels. Look for panels sized to suit the areas you have. I even separated pairs of "suitcase paired" panels to get what I wanted.
Say 500w, div by 12 = 41A, halve that for reality, = say 20A p/h. Digital controllers will tell you how much was produced, that day and 2 days previous,plus instant info amp output, panel voltage, batt voltage.
You have to accept some shading, dull days, etc. Once you check prices you`ll see it is not that expensive, and as well as saving/buying/storing fuel, peace may be with you. Confession of noisemaking sin may be less.
 
That's what I was talking about a couple weeks ago Al. Replacing my canvas with panels. I'm only in it for the shade anyway and if my shade can create electricity makes it a win-win in my book. The MPPT controller seems key to getting maximum output.
 
There is a company down in South FL that builds tops for boats out of solar panels, apparently with nothing under them except frames, Bimini top frame for instance, using some kind of sealing trim between the panels so the rain will not leak through.
 
Is the location data optimized for angle, meaning for the PNW the panels are at a greater angle than for CA? For a horizontal comparison how would the table look?

For land applications I have seen this is definitely the case with a 50 KW array I saw a month ago at Hakai Institute (51 degrees or so N) at about 45 degrees at 2 PM. The same type of array in AZ will auto correct to about 15 degrees in mid afternoon mid summer.

What is the installed weight of your current array and how high above CG?

Good work and it seems you've got a good setup for your cruising style.
 
Solar MPPT charge controller recommendations

I am installing three 150 watt semi-flexible solar panels to my my bridge canvas top. Can anyone recommend a good MPPT charge controller? The panels are 27.5 Vmp. I have a 12 volt system. I assume that I need a 40 amp controller to handle the potential 450 watt output ( I know I wont get 450).
Thanks,
Dave
 
MidNite Solar, model the Kid. Great controller.ImageUploadedByTrawler Forum1417976499.127001.jpg
 
Kyocera was the brand of choice three years ago.

As far as economics, the value of the solar panels comes if you replace generator usage. Doubt if the panels make economic sense if you are replacing shore power.
 
Outback FlexMax 60 would be fine, although a bit oversized for you as it can take up to 750W input for 12 V systems

FLEXmax_60.jpg

As far as economics, the value of the solar panels comes if you replace generator usage. Doubt if the panels make economic sense if you are replacing shore power.
Solar can replace your generator provided that you don't want to have aircon. Although I did add a Honda 2000 portable, just in case.
 
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To piggy-back... I have 275 watts of panels and a MorningStar Pro-Star30. I'm considering adding two more 100 watt panels for 475 total. That would put me over the top on the Pro30, right? (And mine's not MPPT -- I know that already)

Will probably add four more batts first because it's possible a bigger battery bank would eliminate the need for more solar.

What say the experts? Is the ProStar30 limited to 300 watts as I suspect? The paperwork doesn't say so and I've not researched this yet. Still up to my bilges in engine removal.

Does anyone want a Volvo mooring ball? It's sitting in the middle of my pilothouse. For sale. The price you may ask: FREE. But you have to come and get it. (I did take off the water pump, fuel pump, high pressure fuel pump and starter/generator. Those will cost money.) ;)
 
The ability to run the gen for the least amount of time at its rated capacity will improve your "economy". The idea is to run the noise maker the least amount possible and gain every single ounce of energy from every other source possible. Solar is a big step in that direction. The thought process is intense and requires a deep understanding of energy usage and what you really need.
 
To piggy-back... I have 275 watts of panels and a MorningStar Pro-Star30. I'm considering adding two more 100 watt panels for 475 total. That would put me over the top on the Pro30, right? (And mine's not MPPT -- I know that already)

Will probably add four more batts first because it's possible a bigger battery bank would eliminate the need for more solar.

What say the experts? Is the ProStar30 limited to 300 watts as I suspect? The paperwork doesn't say so and I've not researched this yet.


The data sheet for the Prostar 30 indicates it is rated for 30 AMPS. Using 12V and 475W of panels would produce almost 40 AMPS. So theoretically, you probably should have a larger controller. I am not an expert but my understanding is the 475W rating for the panels is based on being at the equator at noon and in reality you will never see anywhere near that wattage in FL. Also, the wattage ratings on solar panels are based on higher voltages which suggests the panels produce lower amperage than you would get with a 12V calculation. For example, the Kyocera 140W panel is rated at 17.7 volts and 7.91AMPs under maximum conditions. I suspect you can get by without a new controller but I would check with the manufacturer first. Certainly they would love to sell you a new MPPT.:hide:
 
To piggy-back... I have 275 watts of panels and a MorningStar Pro-Star30. I'm considering adding two more 100 watt panels for 475 total. That would put me over the top on the Pro30, right? (And mine's not MPPT -- I know that already)

Will probably add four more batts first because it's possible a bigger battery bank would eliminate the need for more solar.

What say the experts? Is the ProStar30 limited to 300 watts as I suspect? The paperwork doesn't say so and I've not researched this yet. Still up to my bilges in engine removal.

Does anyone want a Volvo mooring ball? It's sitting in the middle of my pilothouse. For sale. The price you may ask: FREE. But you have to come and get it. (I did take off the water pump, fuel pump, high pressure fuel pump and starter/generator. Those will cost money.) ;)

Janice, If you add more panels and total 475 watts you will have a potential of 40 amps. Reality is you will probably not get that. If the panels are laid flat you will reach about half that most of the time. Occasionally you might hit 30 but no more. The ideal angle for mounting panels is the latitude that you are at. If you are at 28 degrees then the optimal angle is 28 degrees. Most of the time on trawlers that is not practical. Bottom line, would your 30 amp controller work? probably, but it would be a potential hazard. I would not do it. If you do, make sure you use a 30 amp fuse.

When we had our sailboat I could tilt the panels. I would watch the meter and I would get a 50% increase in the output of the panels by tiling from the flat position to about 25 degrees. That is our latitude. On our trawler we have 4 120 watt panels all laid flat on top of the davits. The highest I have ever seen is 31 amps. Most days about 22 or 23, and usually about 110 to 120 ah. It is still enough to take care of our needs 90% of the time. Honda 2000 does the rest.
 
I am installing three 150 watt semi-flexible solar panels to my my bridge canvas top. Can anyone recommend a good MPPT charge controller? The panels are 27.5 Vmp. I have a 12 volt system. I assume that I need a 40 amp controller to handle the potential 450 watt output ( I know I wont get 450).
Thanks,
Dave

On this site you will find all the necessary tools to your calculations for choosing a régulteur increasingly took to get good and excellent service for your potential purchases.

http://www.altestore.com/howto/Calculators/c36/

See also the summary of my installation made in last May (Post # 34 of 01-17-2014).

Fully satisfied to date for optimal performance.
 

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On this site you will find all the necessary tools to your calculations for choosing a régulteur increasingly took to get good and excellent service for your potential purchases.

http://www.altestore.com/howto/Calculators/c36/

See also the summary of my installation made in last May (Post # 34 of 01-17-2014).

Fully satisfied to date for optimal performance.

Here is the specific link from above that tells you how to size the controller:

How to Size a Solar Charge Controller (PWM Type)

You might also want to note a second ProStar 30 can be added in parallel to your system to provide a total of 60AMPS. If it were my project, I would go with an appropriately sized MPPT.
 
Is the location data optimized for angle, meaning for the PNW the panels are at a greater angle than for CA? For a horizontal comparison how would the table look?

For land applications I have seen this is definitely the case with a 50 KW array I saw a month ago at Hakai Institute (51 degrees or so N) at about 45 degrees at 2 PM. The same type of array in AZ will auto correct to about 15 degrees in mid afternoon mid summer.

What is the installed weight of your current array and how high above CG?

Good work and it seems you've got a good setup for your cruising style.

Hi, so sorry for not looking at this thread sooner and replying to your question.. So, the modeling tool allows one to set the angle of the panels - depending on your installation. One of the 'hints' I offer is to set this to 0, to show the panels are flat on a boat. (Not really totally true, but then with things being dynamic on a boat, 0 is a good estimation IMHO).

Talking to 'Land People', they often have a challenge which angle to set for, as the optimal varies between seasons. So, do I set it for MAX output only during the Summer, with significant loss in efficiency during winter? Or perhaps set them to maximize output during Winter and know there will be some loss opportunity during Summer? Invest in a tracker, or change the angle throughout the year? Most seem to pick an angle between Summer and Winter optimal values. Ah, and one thought things got simple on land :)

Total install weight is for me is around 100lbs, I did not worry about CG issues - nor windage as I set my panels very low (We do not use the upper station at all)
 
. . . . Solar is a big step in that direction. The thought process is intense and requires a deep understanding of energy usage and what you really need.

Kulas is spot on here I think. Solar Panels have some down SO MUCH, that they are worth looking at, but one need to understand the overall system needs... For a weekend cruiser Solar is hard to justify based on $$ savings - but one might want to enjoy the weekend w/o listening to generators. Of course, installing a larger house battery bank might accomplish this as well.

And at dock, with really cheap electricity available (aka, $0.10 / Kwh), Solar can be a tough one to justify.

But in our usage model, away form the docks 8mo. out of the year and totally self sufficient with regards to electricity generation, Solar is a very viable solution. To the point that our ROI us under 2 years.

And if I was looking at our total system today, I would consider downsizing the house battery from 1,800Ah, upsizing the Solar, and perhaps even consider forgoing the Generator. But even that would need some careful planing around reserves and again considering expected boat/system usage.

-al-
 
I am installing three 150 watt semi-flexible solar panels to my my bridge canvas top. Can anyone recommend a good MPPT charge controller? The panels are 27.5 Vmp. I have a 12 volt system. I assume that I need a 40 amp controller to handle the potential 450 watt output ( I know I wont get 450).
Thanks,
Dave


Aside form the good ones noted here, I would offer the TriStar MPPT 45 controller. A bit expensive, but a good solid unit. It is what we have on Viking Star today.

If you are looking at Chinese controllers, be careful as many of the 'MPPT' ones are really PWM controllers. They may maximize the output around PWM, but have no capability to match panel to batteries in a true MPPT way. The lack of a rather large inductor is a primary clue...

And if there are any DIYs out there, I just ordered parts for a open-source MPPT controller I drew up over the past few months:

Smart MPPT Solar Controller

-al-
 
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Thank you gents re the question regarding going to 475... having real estate doesn't mean I need to use it. At least not yet. The most I've ever seen (at FL/GA border) is 17.2 incoming and since I go into absorption charge by 1300 at the latest on a sunny day, the wisest asset allocation is probably more batteries at this point.

The further south I go the more power I'll get so I'll live with the ProStar-30 for the time being. I've got the unit next to where I sit so I can watch the numbers. Today it's totally overcast (miserable, damp and gloomy) yet I'm seeing 1.8 amps incoming. The batteries are showing 13.9. (It's about to flip into flashing lights indicating absorption charge.)

All is well aboard Seaweed. Thank you again for your advice.
 
I am installing three 150 watt semi-flexible solar panels to my my bridge canvas top. Can anyone recommend a good MPPT charge controller? The panels are 27.5 Vmp. I have a 12 volt system. I assume that I need a 40 amp controller to handle the potential 450 watt output ( I know I wont get 450).
Thanks,
Dave


Thanks for all the input. I have ordered a Morning Star 45 amp MPPT.
 

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Can you use one controller for 2 banks? I set mine up with a separate PVs & controller, for each bank. Could one controller feed 2 banks with different draw needs?
 
Originally Posted by Jacques
Fully satisfied to date for optimal performance.[/QUOTE]
On this site you will find all the necessary tools to your calculations for choosing a régulteur increasingly took to get good and excellent service for your potential purchases.

http://www.altestore.com/howto/Calculators/c36/

See also the summary of my installation made in last May (Post # 34 of 01-17-2014).

Fully satisfied to date for optimal performance.
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My install is going well. The Morning Star MPPT is mounted and wired up on the battery, indication panel and controller side. Just waiting on the canvas shop to mount the panels on the top.
 

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