solar charging regulators - Page 5 - Electronic Circuits Projects Diagrams Free

tcmtech · 29th March 2009, 05:41 PM

Sunshine hours is simple, The year round standard is 12 hours of sun followed by 12 hours of dark. But the seasonal variance depends on how far you are away from the Equator.
Prove me wrong!

Actual intensity is almost never a realistic number I have found. Its only an average.

If your solar panels are in a location that gets even a little shade durring some part of the day they will be less efficient. OR if you dont have a full range of tracking from morning until night you wont get anywhere near what the maximum capability of the solar panel is.

And like its been posted on countless threads here. Most solar panel manufatures rate there panel output at bright sunlight while pointing directly at the sun. The real life values are often far less than the manufactures values.

Thunderchild · 29th March 2009, 06:18 PM

ebay, I got 20 W panels for £ 55 (yea some nutcases want as much as 200 but their crroks)

wombweller · 29th March 2009, 06:51 PM

Quote:

Originally Posted by tcmtech

Sunshine hours is simple, The year round standard is 12 hours of sun followed by 12 hours of dark. But the seasonal variance depends on how far you are away from the Equator.
Prove me wrong!

Actual intensity is almost never a realistic number I have found. Its only an average.

If your solar panels are in a location that gets even a little shade durring some part of the day they will be less efficient. OR if you dont have a full range of tracking from morning until night you wont get anywhere near what the maximum capability of the solar panel is.

And like its been posted on countless threads here. Most solar panel manufatures rate there panel output at bright sunlight while pointing directly at the sun. The real life values are often far less than the manufactures values.

My house is situated front east and rear west so at best I get sunlight on my shed 11.00am ish onwards.

ericgibbs · 29th March 2009, 07:06 PM

Quote:

Originally Posted by tcmtech

Sunshine hours is simple, The year round standard is 12 hours of sun followed by 12 hours of dark. But the seasonal variance depends on how far you are away from the Equator.
Prove me wrong!

hi tcm.
You are talking daylight hours, not sunshine intensity at ground level.

Actual sunshine intensity does vary from one annual season to another.

Tree rings are a good indicator of warmth/sunshine for summers in years gone by.

Are you convinced.?

wombweller · 29th March 2009, 07:11 PM

Quote:

Originally Posted by ericgibbs

hi Mark,
The Maplins data says that if the SLA battery is over 12AHr, [yours is 35Ahr] no controller is required.

Also the panel is already fitted with a reverse blocking diode.

Regards

EDIT: a starting point.

et Office: Regional Climate: North East England

Cheers Eric

Did look at the regional met site and couldn't find what you found

Yes I did see that about no blocking diode ect. required for my said battery but this being a GEL battery is this the same? If not I can always buy another.

Just need a supply of empty jam jars, maybe search the bottle bins

Like I said hook up maybe 4 sper bright LED's in each jar and stick them round the garden.Hooked up to a daylight sensor should do the trick.

Cheers Mark

Thunderchild · 29th March 2009, 07:34 PM

Quote:

Originally Posted by wombweller

Just need a supply of empty jam jars, maybe search the bottle bins

Like I said hook up maybe 4 sper bright LED's in each jar and stick them round the garden.Hooked up to a daylight sensor should do the trick.

Cheers Mark

find your local freecycle group (The Freecycle Network) and you will find someone that can give you some jars

tcmtech · 29th March 2009, 08:14 PM

you could have just copied and pasted from my own post.

I said...

Quote:

Actual intensity is almost never a realistic number I have found. Its only an average.

You said:

Quote:

Actual sunshine intensity does vary from one annual season to another.

Your statement is no different than mine. You are using a year to year comparison, I was just using a more generalized comparison.

The actual statement by me was:

Quote:

Sunshine hours is simple, The year round standard is 12 hours of sun followed by 12 hours of dark. But the seasonal variance depends on how far you are away from the Equator.
Prove me wrong!

Intending that you need to prove that you do not have a 12 hour day and 12 hour night when averaged over a one year time scale. And that being farther away from the equator creates a greater difference in the day to night ratio from season to season!

your trying to make a point about a differerent topic made after the "Prove me wrong" statement. Not before it!

I never asked to be proven wrong about intensity levels. I know they are variable given any reasonable time scale!

Hense the being referenced to an average number not an actual number.

**bryan1** · 30th March 2009, 12:35 PM

Well Thunderchild,
Do keep ya eye out for secondhand gelcell batteries and I can't complain as those 30 6 volt 110ah gelcells are still going strong 4 years after I got them from the junkyard. My 350 watts of pv keep them nicely charged even with a full size fridge going and the inverter on 24/7 I'm still dumping around 18 amps into my heating element and the ali backing plate is starting to warp after so much heat everyday. My other bank of 24 2 volt 275ah have only about a 140 watt PV array and they keep em topped up and once a month I change the bank over just to cycle the batteries. Even after 2 solid days machining the bank is still above 26 volts.

If your going 24 volts checkout Kipoint for inverters, my 3kw pure sinewave works perfect and you wont go wrong with one of them. A tip dont buy em off ebay email em direct and you'll get it cheaper.

Cheers Bryan

Thunderchild · 30th March 2009, 12:43 PM

well at present I'm on my old car battery and I'll look for something better in the mean time. do I assume correctly that a SMPS between the panels and battery will increase the efficiency as the panels are 17.5 volts nominal and i need around 13/14 volts or will voltage/current sort of self regulate making it redundant ?

I'm not sure how a SMPS will react to not having enough input amps to put out the amps it would want to though.

**Nigel Goodwin** · 30th March 2009, 01:39 PM

Quote:

Originally Posted by Thunderchild

well at present I'm on my old car battery and I'll look for something better in the mean time. do I assume correctly that a SMPS between the panels and battery will increase the efficiency as the panels are 17.5 volts nominal and i need around 13/14 volts or will voltage/current sort of self regulate making it redundant ?

The voltage will self regulate at the battery voltage.

If your panel can provide considerably more current than the battery can woithstand once fully charged, then use a solar panel regulator to dump the excess energy - this is how it's normally done.

Quote:

I'm not sure how a SMPS will react to not having enough input amps to put out the amps it would want to though.

Using an SMPS to try and keep peak efficiency will help to a certain extent, but the complexity probably isn't worth it - it's probably more cost effectvie just to buy a bigger panel in the first place.

Thunderchild · 30th March 2009, 05:28 PM

Quote:

Originally Posted by Nigel Goodwin

The voltage will self regulate at the battery voltage.

But does that mean that at higher battery voltage less current will be available and at lower voltages more current will be available ?

Quote:

Using an SMPS to try and keep peak efficiency will help to a certain extent, but the complexity probably isn't worth it - it's probably more cost effectvie just to buy a bigger panel in the first place.

well I suppose depends on how much gain, a SMPS is much cheaper than a solar panel and the more panels you have the more you are gaining.

Would I gain more overall efficiency by putting the 2 12 V (well 17.5) panels in series and uning a SMPS to bring the resulting 24-35 volts down to 14 volts ?

**Nigel Goodwin** · 30th March 2009, 05:54 PM

You need to measure the peak power under differing circumstances, under bright sunlight you will get the maximum power, and a direct connection to the battery is probably all that's required. Under poor light a peak tracking SMPS should be able to provide more current to the battery than a direct connection, it really depend how much more it manages, and if it's cost effective.

A while back someone posted here a link to a micro-controller based system for doing just that, perhaps you can find it?.

Bigger panels may cost more, but they provide more power, and it makes the job simple and reliable, as there's pretty well nothing to go wrong.

Thunderchild · 30th March 2009, 06:31 PM

right so really I'm not acheiving much with a SMPS then

**Nigel Goodwin** · 30th March 2009, 11:28 PM

Quote:

Originally Posted by Thunderchild

right so really I'm not acheiving much with a SMPS then

You need to test first and find out - but probably not a lot.

smanches · 31st March 2009, 02:13 AM

You specifically a MPPT controller. It's basically just a buck circuit that tracks the current/voltage curve of the panel.

Solar panels are constant current devices, so it wouldn't matter if you were charging a 6v cell or a 12v cell, it's still charging at the same current. MPPT controllers pull the power at the current panel voltage, then buck it down to the correct charging voltage, thereby increasing current.

On average it's about a 30% boost in full sunlight.

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29th March 2009, 05:41 PM	#61
tcmtech	Sunshine hours is simple, The year round standard is 12 hours of sun followed by 12 hours of dark. But the seasonal variance depends on how far you are away from the Equator. Prove me wrong! Actual intensity is almost never a realistic number I have found. Its only an average. If your solar panels are in a location that gets even a little shade durring some part of the day they will be less efficient. OR if you dont have a full range of tracking from morning until night you wont get anywhere near what the maximum capability of the solar panel is. And like its been posted on countless threads here. Most solar panel manufatures rate there panel output at bright sunlight while pointing directly at the sun. The real life values are often far less than the manufactures values. __________________ "Issue a general safety warning. Then look the other way and allow stupidity the chance to eliminate itself." -- tcmtech "Those who can, Will. Those who can't, will achieve positions of power over those who can and then promptly stop them." -- tcmtech "Your impossibility may just be my day to day routine." -- tcmtech

29th March 2009, 06:18 PM	#62
Thunderchild	ebay, I got 20 W panels for £ 55 (yea some nutcases want as much as 200 but their crroks) __________________ I AM the exeption that disproves the rule in many ways but the rules still apply (unfortunately) www.simonsphotography.org.uk/ - My other hobby www.rushdenrotaract.org.uk/ - make a difference and have fun ! Never buy "Trust" products, all mine broke !!!

30th March 2009, 12:35 PM	#68
bryan1	Well Thunderchild, Do keep ya eye out for secondhand gelcell batteries and I can't complain as those 30 6 volt 110ah gelcells are still going strong 4 years after I got them from the junkyard. My 350 watts of pv keep them nicely charged even with a full size fridge going and the inverter on 24/7 I'm still dumping around 18 amps into my heating element and the ali backing plate is starting to warp after so much heat everyday. My other bank of 24 2 volt 275ah have only about a 140 watt PV array and they keep em topped up and once a month I change the bank over just to cycle the batteries. Even after 2 solid days machining the bank is still above 26 volts. If your going 24 volts checkout Kipoint for inverters, my 3kw pure sinewave works perfect and you wont go wrong with one of them. A tip dont buy em off ebay email em direct and you'll get it cheaper. Cheers Bryan __________________ " The only way to avoid human error is to avoid the use of humans"

30th March 2009, 12:43 PM	#69
Thunderchild	well at present I'm on my old car battery and I'll look for something better in the mean time. do I assume correctly that a SMPS between the panels and battery will increase the efficiency as the panels are 17.5 volts nominal and i need around 13/14 volts or will voltage/current sort of self regulate making it redundant ? I'm not sure how a SMPS will react to not having enough input amps to put out the amps it would want to though. __________________ I AM the exeption that disproves the rule in many ways but the rules still apply (unfortunately) www.simonsphotography.org.uk/ - My other hobby www.rushdenrotaract.org.uk/ - make a difference and have fun ! Never buy "Trust" products, all mine broke !!!

30th March 2009, 05:54 PM	#72
Nigel Goodwin	You need to measure the peak power under differing circumstances, under bright sunlight you will get the maximum power, and a direct connection to the battery is probably all that's required. Under poor light a peak tracking SMPS should be able to provide more current to the battery than a direct connection, it really depend how much more it manages, and if it's cost effective. A while back someone posted here a link to a micro-controller based system for doing just that, perhaps you can find it?. Bigger panels may cost more, but they provide more power, and it makes the job simple and reliable, as there's pretty well nothing to go wrong. __________________ PIC programmer software, and PIC Tutorials at: http://www.winpicprog.co.uk

30th March 2009, 06:31 PM	#73
Thunderchild	right so really I'm not acheiving much with a SMPS then __________________ I AM the exeption that disproves the rule in many ways but the rules still apply (unfortunately) www.simonsphotography.org.uk/ - My other hobby www.rushdenrotaract.org.uk/ - make a difference and have fun ! Never buy "Trust" products, all mine broke !!!

31st March 2009, 02:13 AM	#75
smanches	You specifically a MPPT controller. It's basically just a buck circuit that tracks the current/voltage curve of the panel. Solar panels are constant current devices, so it wouldn't matter if you were charging a 6v cell or a 12v cell, it's still charging at the same current. MPPT controllers pull the power at the current panel voltage, then buck it down to the correct charging voltage, thereby increasing current. On average it's about a 30% boost in full sunlight.