Why is YOUR Solar Panel a Piece of Junk ?

[Mr B]

Brand new MPPT controller, 20 amp. $80-00 Delivered, It is to replace the one I had that got drowned,

But it has to last a long time, and it puts a lot of charge into my Battery bank in that time,
Solar panel doesnt cost that much more, But its useless if the power it generates doesnt go into the batterys.

The point I am trying to make is that the sun is not always shining, so you have to collect as much energy as possible while it is shining,

But there are a lot of different systems out there,

[noelex 77]

For boat sized solar systems it is always cheaper to buy more, or larger panels than the extra expense of MPPT.
The small gain from MPPT is only justified when there is no more room, but this situation is very common on sailboat.
If you are going to fit a MPPT regulator get a good one. MPPT can be implemented in many ways and the cheap regulators give poor results.

[sailrj]

Mr B,

Be careful with the $80, 20 amp MPPT charge controller from China. I bought one and it turned out to be a PWM. There have been several posts about these controllers on CF.

[Mr B]

Originally Posted by sailrj

Mr B,

Be careful with the $80, 20 amp MPPT charge controller from China. I bought one and it turned out to be a PWM. There have been several posts about these controllers on CF.

Thanks for that, I will take piccys and put them on here, I did buy a PWM one but changed it to the MPPT one,

Not being a Electricaly Gifted, I can only go on the information supplied,

Keep tuned. The piccys coming,

[Mr B]

Here we go,

Have a look and tell me whether this is a PWM or MPPT, controller,

I dont have a clue, But it is what the seller called and advertised as a MPPT Controller,

and I did pay for a MPPT controller, As I cancelled the PWM to buy the MPPT one, from the same company, So they did know I wanted an MPPT Controller,

I pulled it apart so the GURU's can see whats inside it,

Sorry about the clarity of the index,

[zeehag]

wow---i have ghad nearly 10yrs good service from flexible annels (unisolar) with my ericson-- and i have been collecting the junk ones others give away when they deteriorate--lol--i have 3 bp panels, each rated at 3 amps, and put out 3.5 amps, i hve a 130 wtt kyocera i got5 free as it is a lil bit crazed from hail... and i have a simens rated 3.88 amps still puts out 3.5 amps and i have a huge 3.88 amp rated unisolar semi flexible still puts out over 3.5-----

please, when you have a deteriorating panel, i can use some more--i will take them off your hands---i dont care about brand name. i dont care about a lil corrosion on the edges---is alll good.

i can even place a 5/8 line over mine to keep em from flying away in a storm and they still put out massive amounts of juice for my batteries.

oh yes, and i use a nicely undesirable pwm controller that is good for total of 25 amps per hour and doesnt fail me-only 80 dollars online.....awesome stuff. my pwm controller has a nice digital gauge for charging input numbers and for battery condition.

i am truly happy with my inferior set up--it works awesome well.

[noelex 77]

Originally Posted by Mr B

Here we go,

Have a look and tell me whether this is a PWM or MPPT, controller,

I dont have a clue, But it is what the seller called and advertised as a MPPT Controller,

and I did pay for a MPPT controller, As I cancelled the PWM to buy the MPPT one, from the same company, So they did know I wanted an MPPT Controller,

I pulled it apart so the GURU's can see whats inside it,

Sorry about the clarity of the index,

I cannot be certain from the photo if it is MPPT, but It definatly has not got the circuitry for good MPPT performance.
One of the difficulties is that thre are many differently ways to implement MPPT. Some controllers stretch the term and their MPPT performance is a bit like calling a rubber band connected to a cars throttle a cruse control.

With reasonably flat batteries try connecting the panels directly to the battery, then via the controler. I would be very surprised if the former output with no controler is not greater ( providing they are nominally 12v panels)

[sailrj]

Originally Posted by Mr B

Here we go,

Have a look and tell me whether this is a PWM or MPPT, controller,

I dont have a clue, But it is what the seller called and advertised as a MPPT Controller,

and I did pay for a MPPT controller, As I cancelled the PWM to buy the MPPT one, from the same company, So they did know I wanted an MPPT Controller,

I pulled it apart so the GURU's can see whats inside it,

Sorry about the clarity of the index,

I'm not an electronics expert, either; but thats the same controller that my electronics Guru buddy proved was a PWM. MY PV's are 24 volt and there was little gain in amps as the voltage decreased. My electronics Guru agreed with the previous post that the internals are lacking to be a true MPPT, but it may have a circuit or two that could be interpreted as "MPPT". Life is never simple. Again, search CF and I have seen other posts on this topic. Good luck.

[Albro359]

20% is a lot to throw away !

Even if you have space for extra panels why not use MPPT to maximise the output?
True if your panels have differoing Vpp then it will be a mixed bag trying to get the max out of them. so make sure all the panels connected to the MPPT are the same.
A simple regulator just clamps the voltage down to 13-14.5, the current stays the same.
MPPT works like a DC transformer, so if for example you have, as I do 2 x 135W panels that have a peak VPP of 23V,then the peak current coming out of them will 135/ 23 = 5.8 A each
Standard regulators just clamp the voltage so the current stays the same ie 5.8A
MPPT maintains the power, so the 23V goes down to 14V, but the current goes up proportionately..so 135W @ 14V = 9.6A...not quite because there are losses, but say its 8.6A vs 5.8A, that's 32%...quite a lot.
SO for my money MPPT is well worth it

[noelex 77]

Originally Posted by Albro359

20% is a lot to throw away !

Even if you have space for extra panels why not use MPPT to maximise the output?
True if your panels have differoing Vpp then it will be a mixed bag trying to get the max out of them. so make sure all the panels connected to the MPPT are the same.
A simple regulator just clamps the voltage down to 13-14.5, the current stays the same.
MPPT works like a DC transformer, so if for example you have, as I do 2 x 135W panels that have a peak VPP of 23V,then the peak current coming out of them will 135/ 23 = 5.8 A each
Standard regulators just clamp the voltage so the current stays the same ie 5.8A
MPPT maintains the power, so the 23V goes down to 14V, but the current goes up proportionately..so 135W @ 14V = 9.6A...not quite because there are losses, but say its 8.6A vs 5.8A, that's 32%...quite a lot.
SO for my money MPPT is well worth it

The numbers you are using are not typical. Vmpp is usually about 17-18v @ a cell temperature of 20c. Typical cell temperatures are 40c and the negative temperature coefficient of the panels means the Vmpp is down to a bit over 16v Shadows will reduce this further. There are some gains to be had converting this voltage to the battery voltage, but once you factor in some inefficiencies in the conversion, the higher self consumption of the MPPT circuitry and some loss in current at the Vmpp (compared with battery voltage) the gains are quite small.
The big problem is if the regulator does not track the Vmpp well then the net result can be negative. This does not occur in the very good MPPT controllers, but these are expensive.

[Mr B]

Originally Posted by zeehag

wow---i have ghad nearly 10yrs good service from flexible annels (unisolar) with my ericson-- and i have been collecting the junk ones others give away when they deteriorate--lol--i have 3 bp panels, each rated at 3 amps, and put out 3.5 amps, i hve a 130 wtt kyocera i got5 free as it is a lil bit crazed from hail... and i have a simens rated 3.88 amps still puts out 3.5 amps and i have a huge 3.88 amp rated unisolar semi flexible still puts out over 3.5-----

please, when you have a deteriorating panel, i can use some more--i will take them off your hands---i dont care about brand name. i dont care about a lil corrosion on the edges---is alll good.

i can even place a 5/8 line over mine to keep em from flying away in a storm and they still put out massive amounts of juice for my batteries.

oh yes, and i use a nicely undesirable pwm controller that is good for total of 25 amps per hour and doesnt fail me-only 80 dollars online.....awesome stuff. my pwm controller has a nice digital gauge for charging input numbers and for battery condition.

i am truly happy with my inferior set up--it works awesome well.

Thats the way Zeehag, I dont care what it looks like either, as long as it works efficently, and the cheaper it is the better I like it,

I laugh at people with their very expensive brand name products, especially when I tell them I bought the same article from the same manufacturer in the same box, with the same specifications, Identical equiptment.
For next to nothing from the manufacturer in CHINA, Where their wizz bang thingo came from as well, Hahahahahahahaha

[bcripps]

Ah-h-h-h-h.... the geeks are taking over!

Guys... this thread is about durable solar panels.

All this about controllers has been covered elsewhere. Please can we get back on topic.

And BRAND NAMES have suddenly become a big secret. Let's have the dirt!

Thanks,
Bryan

[noelex 77]

Originally Posted by bcripps

Ah-h-h-h-h.... the geeks are taking over!

Guys... this thread is about durable solar panels.

You want is to stay on topic? That would create a precedent

I talk with a lot of fellow crusing sailors and with rigid panels failures and defective panels are very rare.
There has recently been an explosion of " home made " or semi home made panels that are available on eBay and from China. It is easy to construct to your own panel or go into limited production. Many of these panels are not as well constructed, or as efficient and my prediction is that they will fail much earlier than the panels from the brand name manufacturers, but solar is getting cheaper and an inexpensive panel with a 5 year life is still likely to be cost effective, so far there seem to have been few failures so the life of the cheap panels is open to speculation.
A bigger problem is the cheap panels are less efficient and on a boat space is at at premium. If you can fit 30% more watts for the same size panel it is worthwhile spending more money for many boats, especially when the cost of mounting the panels, wiring and the charge controler, is often greater than the cost than the solar panels.

Flexible and semi flexible panels are very different with many reports of failures. It is very difficult to pick the best brands of this type of panel. Even so a life of 5-7 years seems typical and some last much longer, which is still good when judged against the lifespan of many marine products although much less than the rigid panels.

[Dave]

Originally Posted by bcripps

Ah-h-h-h-h.... the geeks are taking over!

Guys... this thread is about durable solar panels.

All this about controllers has been covered elsewhere. Please can we get back on topic.

And BRAND NAMES have suddenly become a big secret. Let's have the dirt!

Thanks,
Bryan

I got a wholesale price on 2 X 123 Watt SHARP panels through a contact in the oil patch. NOT warrantied for mobile use anywhere. 3 years out they still look and work like new.

Dave L38 #38

[Zonker]

Yea .. this thread has been funny from the beginning. Nobody questions the quality of HP, Dell or IBM computers - they are the same as these no-name-cheapo computers because the components are from the same source but have a hefty brand-price-tag.

Even the dumbest dummy can build a "marine-proof" solar panel - it's all about putting some solar cells in a water tight frame. The cells are all +/- of the same quality.

If you really want to go with "reliable" US solar panels - then you might try First Solar (ahem ... < 10% efficiency) or Solyndra or any of these other almost bk companies.

Fact is - solar business is not magic and the Chinese made the right decision - KISS - whereas the US tried to make it fancy and failed. If you have failing solar panels, then most likely it's MADE IN USA.