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islander bahama 24
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Discussion Starter · #1 ·
The poly panels are marginally cheaper is there any advantage of one type of panel over the other also do I really need to pay the extra for the mppt controller over the pwm controller for a 200 watt solar installed feeding a 4d two golf cart wet cell lead acid battery bank or should I spend the extra money on more led lights
 

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Beneteau 393
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My understanding is Monocrystaline is made with whole new silica wafers. Poly is made with the left over shards. Mono is smaller, more efficient, more expensive and looks better. But if size is not a problem the real differences must be small.

How many amp hours is 4D?

I had panels directly into the battery bank and it was fine. But I wanted a digital amp meter and volt meter and the cheapest way to buy that was in an MPPT controller. It beats sticking a multi meter into a cigarette socket 6 times per day.
 

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islander bahama 24
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Discussion Starter · #3 ·
Pair of dyno d105 at 225 ah and in series for 12 volt also there is already a volt/ amp meter in the switch panel the cost diference is 9 dollars more for mono panel pair and the pwm controller comes with the kit
 

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Old soul
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I'm in the process of adding more solar to our setup, so have also been doing my homework. From my reading, mono are considered to produce a higher quality crystaline structure vs poly. This produces potentially higher efficiency ratings. Mono is harder to create vs poly. and hence more expensive. However, it seems the gap in efficiency and cost are becoming less and less.

Some discussion I've read warns that quality of build is likely more important than simply looking at raw efficiency ratings.

I have a controller, but it's not an MPPT. It combines both my wind and solar in one controller, and lets me monitor and measure current amp inputs, as well as a cumulative measure for each. It also lets me set the cut off levels to protect the batteries from over charging.

For large solar systems it seems to make sense to spend the extra for a MPPT. So far, I'm not convinced it would matter much with my 200 to 400 watt system.
 

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Re: MPPT, the efficiency advantage is really only during bulk charging, not absorbance or float. If you plan to size/use your solar system mainly to maintain your batteries rather than as a primary charging source, PWM is good enough. If you deplete your batteries significantly between charges (~>25%) and you've got a large enough solar array to contribute meaningfully to the recharge, and you want to recharge quickly, then MPPT will get you an extra 20-30% effective power out of your array.
 

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Bristol 45.5 - AiniA
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When I was looking, I found out that mono panels are not as badly affected by shading than poly. Even the shadow of a shroud across a poly panel takes away something like 30% of your power. I ended up with poly because I could not get the right shape in mono for the place they were going.
 

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I have used both mono and poly. I prefer mono because they are better if there is any shading and also seem better on overcast days.

Controllers - if the panel can supply enough amperage to be of much use you need one.
There is a rule of thumb for this - If I remember correctly - if you are over 1 amp charge per every 100 amp hour battery capacity you need a controller - however I would use a controller on any size system. Low capacity controllers are not very expensive.

The main purpose of a controller is to prevent over charging the battery(s). For small systems any type, even the simple on/off ones will work but the PWM is much better. Power point tracking is usually reserved for larger (>1000 watts) systems which is where it begins to pay for itself.
 

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islander bahama 24
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Discussion Starter · #10 ·
Here's an accurate comparison between MPPT and PWM.

MPPT vs. PWM Controllers Photo Gallery by Compass Marine How To at pbase.com

MPPT wins hands down with a 20.8% gain over PWM with a single 135 watt panel - in Maine.

With the lower prices we are seeing for MPPT I wouldn't waste money on PWM if, as on sailboats, real estate for panels is so limited.
For everyone I am definitely using a charge controller my thing was is it worth the expense to use a mppt not on a 200 watt panel set to charge under 400 ah of wet cell batteries
Brian the 30 amp pwm comes with the panel kit
 

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For everyone I am definitely using a charge controller my thing was is it worth the expense to use a mppt not on a 200 watt panel set to charge under 400 ah of wet cell batteries
Brian the 30 amp pwm comes with the panel kit
A standalone 30A MPPT charger from Rogue costs $350. It may be effectively less than that if you unbundle the kit so you're not paying for the PWM charger, but no matter what, you're probably spending $200 extra for MPPT. As I mentioned in an earlier post, MPPT will give you the equivalent of up to 40W (20% of 200W) of extra power during bulk phase charging. However, since LED uses only 20% the power of incandenscent lighting) if you routinely use 50W or more of lighting at a time and can replace it with LED for the same effective cost as the MPPT, it's a better place to spend your money.
 

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islander bahama 24
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Discussion Starter · #16 · (Edited)
A standalone 30A MPPT charger from Rogue costs $350. It may be effectively less than that if you unbundle the kit so you're not paying for the PWM charger, but no matter what, you're probably spending $200 extra for MPPT. As I mentioned in an earlier post, MPPT will give you the equivalent of up to 40W (20% of 200W) of extra power during bulk phase charging. However, since LED uses only 20% the power of incandenscent lighting) if you routinely use 50W or more of lighting at a time and can replace it with LED for the same effective cost as the MPPT, it's a better place to spend your money.
From renogy its actually cheaper to get the bundle of two 100 w panels the mountings the connectors the wires and the pwm than to purchase the panels alone.found a mono bundle for just over 300 and a hundred and a half just for each panel.
 

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islander bahama 24
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Discussion Starter · #17 ·
Yesterday I replaced two 15 watt and one 25 watt incandescent with a 7.2 watt led light in the galley. And a 3.5 watt light in the passageway and head dad wanted brighter lighting so 55 watts incandescent changed to about 14 watts led cutting power usage by about 75% and the lights cost me 38 bucks deliverd. Should have taken pics for low buck thread
 

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Yesterday I replaced two 15 watt and one 25 watt incandescent with a 7.2 watt led light in the galley. And a 3.5 watt light in the passageway and head dad wanted brighter lighting so 55 watts incandescent changed to about 14 watts led cutting power usage by about 75%.... thread
The Led lights should be brighter than what you had. I usually figure a factor of 10. In other words a 10 watt incandescent can be replaced by a 1 watt led for the same or greater brightness.
 

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islander bahama 24
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Discussion Starter · #19 ·
The Led lights should be brighter than what you had. I usually figure a factor of 10. In other words a 10 watt incandescent can be replaced by a 1 watt led for the same or greater brightness.
I was not telling it right I put in the lights that use more power than I wanted to dad has macular degeneration the 7.5 watt light puts out about equivalent of 100 watts incandescent and the others are 50 watt equivalent lots brighter than I would have installed for myself
 

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From renogy its actually cheaper to get the bundle of two 100 w panels the mountings the connectors the wires and the pwm than to purchase the panels alone.found a mono bundle for just over 300 and a hundred and a half just for each panel.
Since the PWM is essentially free and since your Dad's vision situation requires bright lighting, I'd say you're putting your money in the right place with the LEDs. You can always upgrade to an MPPT controller later without much trouble.
 
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