Ook's journey into PV land

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Communica in Midrand have a 3000w Synapse 3.0V+ inverter/regulator, 350w PV panels and deep-cycle batteries.

A pure-sine inverter may be a bit more expensive, but in terms of effectiveness it is a better purchase as your fridge motor and other electronics do not like modified sine, and may actually consume more power.


I purchased extra cable (10m) and the final price was around R15700. Not a bad price TBH. Only niggle was that they did not have the MC4 connectors. Went to ACDC and got these. You also get connectors for connecting panels in series or parallel. Makes connecting things so much easier.

You will definitely need those connectors. Please don't try to be clever and use rinkydinky DIY connectors, DC voltages can be deadly, and it is worth the money to do it properly the first time.

mc4-connector-500x500_1400x.jpg

Communica in Midrand have a 3000w Synapse 3.0V+ inverter/regulator, 350w PV panels and deep-cycle batteries.


I purchased extra cable (10m) and the final price was around R15700. Not a bad price TBH. The cable is a special type of cable, with a thick covering and a single core of conductive material. You'll notice some shops sell red and black cable (highly recommended) and others sell cable that's marked with regular red or white stripes for positive and negative.

Take in mind our Eskom account was (we terminated it a week ago, so getting a good PV system was a priority) more than R2500 per month, although we used electricity very sparingly. Bastards loaded it with transmission costs etc.

We will recoup it in 7 months. Once there, we can look at either improving it or getting a better system which you can upgrade by adding more panels and batteries.

So far everything works 100% - can run laptop, fridge, washing machine without any issues. But the 2x 100Ah is not enough storage to keep the fridge running 24x7 but YMMV. For now it is miles better than paying R2500 per month and trying to content with power failures etc. My idea is to get a timer and put the fridge on the timer, letting it run between 05:00 to 21:00. During night nobody opens the fridge, and it stays cool for long enough anyway.

Keep in mind if you need to run more equipment at night (like a TV set, or a laptop/desktop) you'll need to look at a different system that can handle extra batteries and PV panels easily.

Take in mind our Eskom account was (we terminated it a week ago, so getting a good PV system was a priority) more than R2500 per month, although we used electricity very sparingly. Bastards loaded it with transmission costs etc.

We will recoup it in 7 months. Once there, we can look at either improving it or getting a better system which you can upgrade by adding more panels and batteries.

So far everything works 100% - can run laptop, fridge, washing machine without any issues. But the 2x 100Ah is not enough storage to keep the fridge running 24x7 but YMMV. For now it is miles better than paying R2500 per month and trying to content with power failures etc.

Keep in mind if you need to run more equipment at night (like a TV set, or a laptop/desktop, extra security lights - preferably LED based) you'll need to look at a different system that can handle extra batteries and PV panels easily.

Oh, and one final thing - the Synapse inverter/regulator allows you to charge your batteries from a generator, it have that functionality. If you have a 3kVa genny, you can wire it up, and when the batteries run a wee bit flat (in the case of extended inclement weather) charge them with the generator plus run the fridge etc as well.
 
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For cellphone and tablet charging (as well as for a couple of 12v solar lights) we've got two extra PV panels, one a 20W and the other a 30W panel, the 20W panel charges a 18Ah battery, and the 30W panel charges a 33Ah battery.

12v charging is more efficient than charging via an inverter then back through a wall wart.
 
For cellphone and tablet charging (as well as for a couple of 12v solar lights) we've got two extra PV panels, one a 20W and the other a 30W panel, the 20W panel charges a 18Ah battery, and the 30W panel charges a 33Ah battery.

12v charging is more efficient than charging via an inverter then back through a wall wart.
How long does the 33ah take to charge?
 
With no load and a sunny day, anything from two hours to four hours (depending how flat it is)
With a 30w panel? That's pretty quick actually. Trying to find 12v floodlights so I can do a 30w solar panel hookup like that.
 
We also played around with the idea of converting a fridge to 12v (yes, you do get 12v fridge motors) but the problem with that is, if it packs up, you'll pay through the nose for another one.

So it actually works out cheaper (and quicker) to go with an inverter and a standard low-energy fridge.
 
My idea is to get a timer and put the fridge on the timer, letting it run between 05:00 to 09:00. During night nobody opens the fridge, and it stays cool for long enough anyway.
You're only going to run the fridge for 4 hours per day?
 
Most China malls got lots of interesting doohickery 12v stuff. Shop around.

Do not be ashamed to shop at big names like ACDC and Communica and compare prices. Solar panels are cheaper at ACDC than at the China mall, but china mall batteries are cheaper... if you don't mind buying a bit here, a bit there etc.
 
doh, edited my post, fat fingers. Thanks for pointing it out. Meant to say from 05:00 to 21:00
Ok - but eight hours is double the recommended time that your fridge can be off before food starts spoiling. Maybe once in a while but nightly and during the summer would seem ill advised.
 
With a 30w panel? That's pretty quick actually. Trying to find 12v floodlights so I can do a 30w solar panel hookup like that.
Protip - get a motion sensor floodlight. And a couple of 5w or 10w lights, which have a small power draw.

The idea is the small lights can stay on through the night, but if something triggers the motion sensor, the big lights come on.

Or you can just use motion sensor lights.
 
Suggest fix up your post, a lot of repeated paragraphs in there.

You also want to move to Lithium once you can afford it.
Costs for that are higher initially, but you get more lifetime and capacity vs Lead Acid.
 
Ok - but eight hours is double the recommended time that your fridge can be off before food starts spoiling. Maybe once in a while but nightly and during the summer would seem ill advised.
If sealed properly your fridge can be off for about 24 to 36 hours as long as no one opens and closes the doors a lot.
 
Suggest fix up your post, a lot of repeated paragraphs in there.

You also want to move to Lithium once you can afford it.
Costs for that are higher initially, but you get more lifetime and capacity vs Lead Acid.
Saw such a system at Communica, was R35000 something... but it was a complete system with circuit breakers etc.

It looked really neat. And heavy. I did not touch it, just looked at it.
 
If sealed properly your fridge can be off for about 24 to 36 hours as long as no one opens and closes the doors a lot.
The freezer, if it's full, but not the fridge. Of course a lot depends on the contents of your fridge.
 
You'd think that, but from experience it can last a lot longer than 8 hours.
Like I said it depends on the food that you're storing. Doing it night after night will also have an impact.
 
Like I said it depends on the food that you're storing. Doing it night after night will also have an impact.
I think Ook will have to see how it works out for him.
 
Please be careful buying cheap Chinese MC4 connectors for solar panels. Don't mess around with DC because there is no zero point crossover extinguishing like AC.

Scary stuff:

 
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