Solar panels

Neil’s waiting to see if there really is a StBernard with a barrel of brandy. Reckon the guy in the 4x4 was the advance party.
On a more serious note. I will phone him every morning to see if he’s still in the land of the living. We don’t want to have him taking up a rally vacancy, if he’s no longer with us.lol I did remind him not to eat any yellow snow .
 
I am a bit too short Eric, son in law gets on the roof that way but I would probably break my neck lol. Doesn’t matter as I would maybe get 2 amps when sun at its highest, was more a joke really.

Just had a 4x4 full up nearby and the guy came to check if I was okay and if I needed anything as he has seen me here a few days. Thought that was nice of him. He said he didn’t think I would be getting anywhere if I wanted to, there are abandoned cars all over the place. Del just got out in time yesterday morning as he doesn’t like snow but Charlie is spitting feathers that he is missing it lol

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That's a bit more than we have in Hampshire, had some snow here but only about an inch at best. Expecting more today.
 
You need to try harder, think electric motor.
Or what about a big windscreen wipery thingy Bob.???
After all you've got loads of time on your hand sat in the snow in a wooded lane somewhere in Derbyshire.
I have a extending ice scraper, scraper one end brush the other, Aldi or Lidl, cheap as chips & tall fold up plastic step; Shorty still can't reach, so I would have to do it.:D
 
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Can anybody help, new to solar power! . I have a 100 watt panel inside my front window and it reads 14+.
But when I connect to battery it reads 12.1or 2. Many thanks in advance.
 
I asume it has a regulator in line with your panel.
The reason the voltage drops is because the panel will be charging the battery so in time the voltage will rise as the battery is charged up.
You can check this by measuring the voltage of the battery periodically with the panel removed and you will see the battery voltage increasing.
I hope this helps.
 
Can anybody help, new to solar power! . I have a 100 watt panel inside my front window and it reads 14+.
But when I connect to battery it reads 12.1or 2. Many thanks in advance.

You wont get much output unless it's in full sun, but it will depend what your battery voltage is, if that is 12volts it will drop the solar voltage down until the battery is charged. You could put an ammeter in line and see what you are getting, mine is running at about 2amps but flat on the roof. I think you will also find that your output will be lowered because your panel is behind a window. Are you using a controller?
 
Can anybody help, new to solar power! . I have a 100 watt panel inside my front window and it reads 14+.
But when I connect to battery it reads 12.1or 2. Many thanks in advance.
You should not be connecting a 100 watt solar panel to a battery. There should be a solar controller in between
The panel will be at about 16 to 18v in full sun with no load. The battery will be at 12 to 13.8v.
Join them together and the voltage of the panel will be the voltage of the battery. The panel will try to charge the battery, so that voltage will rise.
So in time and in bright sun, the panel will bring the voltage up to the point that the battery is ruined.
Thats why a controller is vital.
At this time of year, solar panels do almost nothing.
 
You should not be connecting a 100 watt solar panel to a battery. There should be a solar controller in between
The panel will be at about 16 to 18v in full sun with no load. The battery will be at 12 to 13.8v.
Join them together and the voltage of the panel will be the voltage of the battery. The panel will try to charge the battery, so that voltage will rise.
So in time and in bright sun, the panel will bring the voltage up to the point that the battery is ruined.
Thats why a controller is vital.
At this time of year, solar panels do almost nothing.
 

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That looks like a standard non-MPPT charge controller, though the wires look a bit thin!
In the feeble sun we get at this time of year, the controller will be passing through what power the panel can produce. The internal resistance of the panel will drop the voltage down to the voltage of the battery.
It looks as if it is working as it should.
 
That looks like a standard non-MPPT charge controller, though the wires look a bit thin!
In the feeble sun we get at this time of year, the controller will be passing through what power the panel can produce. The internal resistance of the panel will drop the voltage down to the voltage of the battery.
It looks as if it is working as it should.
What is an mppt charge control and what does it do.
 
What is an mppt charge control and what does it do.
The charge controller controls the charge (you knew that!).
A "normal" one works like a sort of tap: it limits the voltage output to the maximum the battery is happy with and it limits the current to the maximum the battery is happy with.
For rather technical reasons, this is alway going to waste a lot of potential power. In bright sun, the panel will put out 16.6v at 6A but the battery can only take 13.8v so the output is limited to 13.8v at 6A.
A controller with Maximum Power Point Tracking (MPPT) adjusts the power coming from the panel to get the best possible balance of volts and amps, then converts that to the best combination for the battery.
In the example above, the input might be the same (or perhaps a little better), but the output will be 13.8 at 7.25A. About 25% more.
Typically, an MPPT controller costs about £65 or more instead of about £10 or more, and gives 25% to 30% more output from the same panel(s). So for a 100W panel, it isn't worth the extra outlay, but for more or bigger panels, it is.
 
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The charge controller controls the charge (you knew that!).
A "normal" one works like a sort of tap: it limits the voltage output to the maximum the battery is happy with and it limits the current to the maximum the battery is happy with.
For rather technical reasons, this is alway going to waste a lot of potential power. In bright sun, the panel will put out 16.6v at 6A but the battery can only take 13.8v so the output is limited to 13.8v at 6A.
A controller with Maximum Power Point Tracking (MPPT) adjusts the power coming from the panel to get the best possible balance of volts and amps, then converts that to the best combination for the battery.
In the example above, the input might be the same (or perhaps a little better), but the output will be 13.8 at 7.25A. About 25% more.
Typically, an MPPT controller costs about £65 or more instead of about £10 or more, and gives 25% to 30% more output from the same panel(s). So for a 100W panel, it isn't worth the extra outlay, but for more or bigger panels, it is.

You can get MPPT controllers for much less than £65. See as example https://www.ebay.co.uk/itm/5C95-30A...047203?hash=item468ed53163:g:B70AAOSwpW5cT9zj

I believe I am correct in saying that with an MPPT you can connect panels of difference wattages and the system will work correctly but with PWM you lose power, as the different panels try to charge each other, well something like that.
 
You can get MPPT controllers for much less than £65. See as example https://www.ebay.co.uk/itm/5C95-30A...047203?hash=item468ed53163:g:B70AAOSwpW5cT9zj
Sadly, I am almost entirely certain that's a PWM controller with MPPT written on it.

I believe I am correct in saying that with an MPPT you can connect panels of difference wattages and the system will work correctly but with PWM you lose power, as the different panels try to charge each other, well something like that.
Not really. The panels will all have diodes to prevent current going the wrong way.
You can connect multiple panels together in parallel with a PWM controller.
With an MPPT controller, you can connect them in parallel or in series.
I have two 100watt panels in my garden, set almost vertical, facing south, connected to a good MPPT controller. They're connected in series so that even feeble light will give enough voltage to produce a tiny bit of charge. In Summer, they would be more efficient connected in parallel, but I don't need the power then, so I don't bother.
 
The charge controller controls the charge (you knew that!).
A "normal" one works like a sort of tap: it limits the voltage output to the maximum the battery is happy with and it limits the current to the maximum the battery is happy with.
For rather technical reasons, this is alway going to waste a lot of potential power. In bright sun, the panel will put out 16.6v at 6A but the battery can only take 13.8v so the output is limited to 13.8v at 6A.
A controller with Maximum Power Point Tracking (MPPT) adjusts the power coming from the panel to get the best possible balance of volts and amps, then converts that to the best combination for the battery.
In the example above, the input might be the same (or perhaps a little better), but the output will be 13.8 at 7.25A. About 25% more.
Typically, an MPPT controller costs about £65 or more instead of about £10 or more, and gives 25% to 30% more output from the same panel(s). So for a 100W panel, it isn't worth the extra outlay, but for more or bigger panels, it is.
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Well I finally got my gas struts fitted today and they work perfectly.The panel just floats up out of your hands. All you need to do is pull them back with the strap to the position of the sun and put rigid supports in place......it’s as simple as that!!! Really well chuffed at the way it’s turned out!
 

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