Solar Panels

[Boatguy30]

I guess my point, is I have seen many news stories about premature panel failures in land applications over the last year or so. I have never heard of a failed Siemens panel and most burn out after 30 years or more.

In 5 years time, if I'm out in the Marshall Is where do I get a new solar panel when I need if?

[scoobert]

Originally Posted by Boatguy30

I guess my point, is I have seen made news stories about premature panel failures in land applications. I have never heard of a failed Siemens panel and most burn out.

In 5 years time, if I'm out in the Marshall Is where do I get a new solar panel when I need if?

you cannot. and as i said, all panels can fail. losing one, as long as they are run parallel is not a big deal. you replace it when your back in a reasonable location. all the panels i have listed are covered by a 20-30 year warranty. If you want a brand that has been out for a long time, get the sharp panels. That company is not going anywhere, and is a world wide company. Paying extra for a name, in solar panels, is not that smart. i don't care what name is on them, they are silicon, made from sand, and the structure is the same.

[s/vPainkiller]

Here's a vote for buying a reputable name brand backed by a solid warranty. We have Kyocera panels. You can definitely buy cheaper. I paid almost $3 per watt for 2 - 135 watt panels. I have heard from multiple sources, one of them a dealer in the business for many years, that A) Kyocera panels largely don't fail and they hold their output over many years, and B) if they do fail, they replace no questions asked even after 20 years.

I hope it never becomes an issue for me, but feel more confident knowing that if/when I have a problem, they will stand behind the warranty.

We also have a Blue Sky MPPT controller. I can't compare it to other makes, but so far it operates as advertised.

Scott

[Empty Pockets]

OK, I'm starting to try and sort out the same things for my boat. 42' starting out in the Caribbean.
Everyone says get as much as you can fit. 600W! 1000W! I have to ask like others have, what are you running? Or maybe I'm way underestimating my needs?

From a BoatUS article:

100-Watt Solar Panel
Typical Output/Week*= 3,500 Watt Hours

* Based on 5 hours of charging in full sunlight.

In a Typical Week You Can Run Watt Hours Required
12vDC bilge pump (36-watts) for 3 hours 108
19” color TV (70-watts) for 7 hours 490
VCR (40-watt) for 4 hours 160
Furnace fan (400-watt) for 3 hours 1,200
Satellite dish (40-watts) for 7 hours 280
2 fluorescent lights for 14 hours 448
Cassette player (30-watts) for 7 hours 210
Laptop (40-watt) for 7 hours 280
Coffee maker (900-watts) for 20 minutes 300
Total 3,476 Watt Hours

I don't have a TV, VCR, furnace, satellite dish, or coffee maker. Is the refrigerator the killer? Maybe 750 watts a day. The math still looks like 200W should be plenty?
What am I missing?
Another question. If I wanted 200W, would I be better off with 4 50W rather than 1 200W? Aside from the initial wiring, if one blows, the others are still working? And if one goes to sleep in the shade, the others still put out?
I'm sure the answers will bring up more questions.
Thanks in advance,
Pete

[tartansail]

Originally Posted by noelex 77

Why not indeed
That is a good plan especially now that solar watts are so cheap.

I would still encourage people to do some calculations it can answer questions such as is worth purchasing the more expensive high efficiency panels which will pack more watts into the given space, or a more expensive controller that will get a bit more power out of the same number of watts.

With the sort of array you are talking about Outback and Midnite make the best controllers it may be worth getting a model that is slightly oversize in case you decide to squeeze more watts in place in the future.
Many people once they have lived with the quiet, reliable, free power of solar want to be able to do with out their generator completely.

One advantage of solar is that the batteries get a much easier time. The solar panels will drive most of the loads over the 10hours or so that they are charging meaning that the draw from the batteries is less.
With solar you can get away with a smaller bank, there is also no need for battery type and size that will accept the high charge rate possible from a generator.
So it may be worth seeing how much of your power is produced by solar before deciding on the size and chemistry of a new battery bank.

Or you could do some calculations to tell you before hand

I follow these threads to get the insights from Noelex and some of the other electron gurus. However, I'd like to suggest a caution on the "smaller bank" issue. When you size your bank you need to be realistic about power consumption after dark. Especially with a refer/freezer, you could be in great shape from daytime solar production and still be harming your batteries with too much drain overnight.

As to the sizing question, we're doing fine in New England with 250 watts and a 460Ah bank of Sam's Club golf cart batteries. However, if we were full time liveaboards, I'd probably be looking to bump both by half so the Admiral and I weren't disagreeing on the need for the extra lights to be on.

[s/vPainkiller]

Originally Posted by Empty Pockets

OK, I'm starting to try and sort out the same things for my boat. 42' starting out in the Caribbean.
Everyone says get as much as you can fit. 600W! 1000W! I have to ask like others have, what are you running? Or maybe I'm way underestimating my needs?

From a BoatUS article:
100-Watt Solar Panel
Typical Output/Week*= 3,500 Watt Hours

Pete,
This can be overwhelming at first. I highly recommend spending some time perusing the archives. There have been a lot of threads on solar installations. There are a number of very experienced folks on CF with a lot of very informative posts. Take some time to digest what has been covered. It will help a lot.

Now a couple things I have learned. You can use 1/3 of the wattage as a rule of thumb output per day in amps. We have 270 watts total, so on an average day, we'll put in 90amps to the batteries. Note this means that on a cloudy day, you'll get less.

We have a dedicated fridge and freezer. On our boat this is the main consumer. I assume for purposes of the energy budget, that these run a 50% duty cycle. For consumption purposes, I assume that each one uses 50 amps per day or 100 amps total. The reality in the summer in SC, we consume way more than that. Cruising during the winter in the Bahamas, 50% might be about right.

For the rest of your budget, you also have to make assumptions about what is running and how many hours per day. Nav electronics, lights, entertainment, pumps, inverter, water maker, etc. It all adds up.

Remember that a few cloudy days will draw your battery bank down. Not a problem if you have other means of charging. However, if you are going to solely rely on solar for your charging needs, you need to consider worst case. That is why many advocate putting the most you can fit/afford.

FYI we also have a wind generator and Honda 2000 in addition to our main engine alternator. Battery bank is 800AH AGM's.

Hope this helps.
Scott

[jeremiason]

We have run Kyocera Solar Panels on our boat for 4 years without problems... They have a five year warranty on materials and workmanship and a 20 year warranty on power output.

We purchased them from NORTHERN ARIZONA WIND & SUN, which has some of the best prices in the USA.

We run a BlueSky Controller 3048, which takes 36v to 48v from the panels. Unfortunately, they don't make this model any longer. We use the panels in paired series... That produces a maximum of about 48 amps to the batteries at peak sunlight or about 300 ah per day. When in sunny places, that kept us on the hook indefinitely.

We found we were using the GenSet for heating the hot water and run the AC to put a load on it.

When we got down to the southern part of Central America we found the power from the panels decreased significantly due to the frequent Squalls and cloud cover.

Our plan is to install a AirMaax Marine Wind Generator to compensate for the lose of solar power on cloudy days. Although expensive, this wind generator is Military Spec'd, almost bullet proof in its construction and has very high output at low wind speeds.

[scoobert]

Originally Posted by Empty Pockets

OK, I'm starting to try and sort out the same things for my boat. 42' starting out in the Caribbean.
Everyone says get as much as you can fit. 600W! 1000W! I have to ask like others have, what are you running? Or maybe I'm way underestimating my needs?

From a BoatUS article:

100-Watt Solar Panel
Typical Output/Week*= 3,500 Watt Hours

* Based on 5 hours of charging in full sunlight.

In a Typical Week You Can Run Watt Hours Required
12vDC bilge pump (36-watts) for 3 hours 108
19” color TV (70-watts) for 7 hours 490
VCR (40-watt) for 4 hours 160
Furnace fan (400-watt) for 3 hours 1,200
Satellite dish (40-watts) for 7 hours 280
2 fluorescent lights for 14 hours 448
Cassette player (30-watts) for 7 hours 210
Laptop (40-watt) for 7 hours 280
Coffee maker (900-watts) for 20 minutes 300
Total 3,476 Watt Hours

I don't have a TV, VCR, furnace, satellite dish, or coffee maker. Is the refrigerator the killer? Maybe 750 watts a day. The math still looks like 200W should be plenty?
What am I missing?
Another question. If I wanted 200W, would I be better off with 4 50W rather than 1 200W? Aside from the initial wiring, if one blows, the others are still working? And if one goes to sleep in the shade, the others still put out?
I'm sure the answers will bring up more questions.
Thanks in advance,
Pete

a few things here.
first, who owns a VCR?
second, laptops can use over 150watts, when being used.
my personal laptop uses about 250watts at full load.
fridge is not mentioned, and uses the most power.

[scoobert]

Originally Posted by jeremiason

We purchased them from NORTHERN ARIZONA WIND & SUN, which has some of the best prices in the USA.

Kyocera 215 can be had for $246 there, not a bad premium if your a fan of the brand. much better then the $3 a watt i have seen elsewhere. only drawback is the necessity of a MTTP controller.

[jkindredpdx]

You're on the right track, buying all you can afford. I probably made a mistake. I bought small as a proof of concept planning to upgrade later.
I got 4 X 15w on sale at http://="http://www.wholesalesolar.c...salesolar.com/. The guys there were very helpful and have been at it awhile. The panels meet my needs so far (3 years) and upgrading isn't high on my project list. Do it right and do it once cuz it might be awhile before you circle back.

[scoobert]

Originally Posted by jeremiason

Our plan is to install a AirMaax Marine Wind Generator to compensate for the lose of solar power on cloudy days. Although expensive, this wind generator is Military Spec'd, almost bullet proof in its construction and has very high output at low wind speeds.

i spent about 10 min looking at this product, and found no spec sheet, and no output graph. kinda fishy. what size is it even?

here is a 400 watt marine unit for less then $1000
Air-X Marine 12V

for $2500 it had better be 1000 watts, or more.... doubtful.

[Empty Pockets]

Tom,
Do you have any pics of the panels on the boat? That's a lot of power. My boat's only 42 to your 47, but I'm trying to figure out where to put them all.
Pete

[scoobert]

Originally Posted by Empty Pockets

Tom,
Do you have any pics of the panels on the boat? That's a lot of power. My boat's only 42 to your 47, but I'm trying to figure out where to put them all.
Pete

the best mounting places are.
the obvious dingy davit, and the not so obvious safety rail/lifeline mount.
i could put 24, 240 watt panels on my lifelines :P

[jkindredpdx]

Originally Posted by Empty Pockets

Tom,
Do you have any pics of the panels on the boat? That's a lot of power. My boat's only 42 to your 47, but I'm trying to figure out where to put them all.
Pete

I'd say it depends so much on your boat and your traffic pattern. I'm on a center cockpit and didn't want to mount over my dodger, so mounted to my stern rail. That seems to get me the rays, but might not be such a good idea if I was towing a dinghy.

[noelex 77]

Originally Posted by Empty Pockets

OK, I'm starting to try and sort out the same things for my boat. 42' starting out in the Caribbean.
Everyone says get as much as you can fit. 600W! 1000W! I have to ask like others have, what are you running? Or maybe I'm way underestimating my needs?

From a BoatUS article:

100-Watt Solar Panel
Typical Output/Week*= 3,500 Watt Hours

* Based on 5 hours of charging in full sunlight.

In a Typical Week You Can Run Watt Hours Required
12vDC bilge pump (36-watts) for 3 hours 108
19” color TV (70-watts) for 7 hours 490
VCR (40-watt) for 4 hours 160
Furnace fan (400-watt) for 3 hours 1,200
Satellite dish (40-watts) for 7 hours 280
2 fluorescent lights for 14 hours 448
Cassette player (30-watts) for 7 hours 210
Laptop (40-watt) for 7 hours 280
Coffee maker (900-watts) for 20 minutes 300
Total 3,476 Watt Hours

I don't have a TV, VCR, furnace, satellite dish, or coffee maker. Is the refrigerator the killer? Maybe 750 watts a day. The math still looks like 200W should be plenty?
What am I missing?
Another question. If I wanted 200W, would I be better off with 4 50W rather than 1 200W? Aside from the initial wiring, if one blows, the others are still working? And if one goes to sleep in the shade, the others still put out?
I'm sure the answers will bring up more questions.
Thanks in advance,
Pete

The output quoted for a 100w panel is a bit optimistic. Certainly achievable in areas of good insolation, but as an average its too high. 3500 wHrs a week is about 35-38 AHrs a day.
Location and time of year are obviously critical to solar output and I would suggest calculations based on your likely cruising ground and time of year are going to be much more meaningful.
I have not read the BoatUS article but most of the rest of the figures are now out of date LCD TVs, MP3 players and LED lighting is used.

4x50w will give a bit more output on a boat than 1x200w for the reasons mentioned, but 4x50w is generally physically larger than a single 200w panel because of panel framing etc. The high efficiency panels increase the gap further and are only available in large high wattage panels.