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37 minutes ago, Don said:

I just know my electricity bill has come down from R2500-R3000 a month to R200 (R176 to be exact),

You see now - TTT just got everyone realizing that they are on a fools errand and then you cock it all up by showing them real ROI.

The investment guru's say that for every R4000 pm required in retirement you will need R1mil in the bank (at budgeted 5% draw down) - so if you are saving R2000 a month then it is like you have just deposited R500k with Alan Gray - not too shabby! Of course the looming battery bank replacement may have the same effect as heart transplant surgery for the average pensioner!:)

 

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Thanks guys you have really opened my eyes. I now see that if I want to save money on power solar is not the cheapest way to go. I still would like to buy the solar components one at a time when I have the money to do so. What's your advice on the first thing to buy? Inverter, charge controller, solar panels and or battery bank. I know the cables and fuses would be the last thing to get. My electrician friend will do the wiring for a bottle of Bells which I give him after the job. Lol

Sent from my SM-A500F using Tapatalk

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I think one of the biggest barriers is that you need to buy everything at once more or less. I suppose it would make most sense in a grid tie situation to buy an inverter and a few panels first, then you can add panels incrementally later, once the wiring is sorted out and tested.

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Spot on guys!

FWIW, on another forum years ago we had a chat of Have's and Have Not's. It started when people said they will have a farm and grow all their food if the Gov. mess it all up. Same applies for Solar and water in cities, even more so I think. The Have Not's see what the Have's got and because the Have Not's are more than the bullets the Have's can store and use, the Have Not's take it all and move onto the next Have'er. If you do it for darker tougher times, you need to do it right so that no-one knows you are a Have'er. ;)

Any case, that is darker than the night with no moon and clouds subject and can be seen as fear mongering, even though in cities in has a "that make sense" ring to it.

 

We should have a Required Reading Section (RRS) for all newbies, asking why do you want to go solar, then explaining the costs, the pro's and con's of solar vs grid tie after they have read the new battery manual section and understand their local regulations ito feeding back. 

It is EXACTLY the same decision process for all of us as it boils down to in the end to one of 2 options:
Option 1: Getting the biggest bang for your buck spent.
Option 2: The most FUN in spending it on Solar.

 

Back to the matter at hand. @Newbie Charles, what are your thoughts after reading the above iro why you want to go Solar? 

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I lived in Hilton, KZN for 18 months while building a house on a small holding. In Hilton you normally only have 2 of the following: Lights, water or telephone. To mitigate this I installed LED lights throughout the house and a 1kva inverter on a relay on the light circuit. 2 102 Ah batteries powered the system and those were trickle charged with an electric fence charger while eskom was on. One plug was connected to the light circuit for the ADSL modum. 

This system helped with the numerous outages and is obvious to most members on this forum. Its cheap to install. The inverter was an old camping modified sinewave that cost about R1500. With a couple of solar panels and an MPPT it could be an off the grid project. It won't save money, but is a useful entrance to solar. 

I am now completely off the grid. Just had eskom lines through the farm removed. 

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12 hours ago, pilotfish said:

You see now - TTT just got everyone realizing that they are on a fools errand and then you cock it all up by showing them real ROI.

You see, that is one of the things that make solar so difficult to cost.

Let me explain. You don't work from home. Lets say you have a bill of R2000-R5000 and you decide to go solar. Everyone tells you to reduce your consumption to save on batteries and all that.

So you go out and do it. The question is: Do you do it BEFORE you solarize, or AFTER you bought the batteries?

If you do it, following the same stringent rules as if you had batteries i.e. measure your consumption day and night, switch things off, energy efficient pumps and fridge/freezers and geyser on EV tubes, gas stove, all the stuff we have done AFTER we installed our systems, you will turn the R2000.R5000 into R100-R1000 pm having spent 'n "pophuis vol geld" on reduction, energy efficient devices and made the family change their habits. Open Energy Monitor is a prime example on how to manage and save electricity, switching things on and off with cool devices using Pi's.

So after you have learned and understand your usage and consumption you realise, hold on, I have spent a "pophuis vol geld" already to reduce consumption, and going forward with solar only really leaves the evening loads i.e. batteries. Suddenly the whole picture changes.

Take my setup. After spending all the monies on first reducing, after I bought a Efergy meter and having studied the results for months, reducing month after month, I have the exact amount of panels to power the home office on average for a Cpt setup which is worse ito winter and rainy season. Once the solar system kicks in the house draws 60w on average, to solarise that is just not viable. Evenings are where most of my expense go as kids and computers are home and batteries will never ever be viable.

So my advice is, make a study of ones consumption, as if you have batteries, reduce your consumption to where it is comfortable / realistically do-able, NOW do the sums for solar.

And wot @Dave said - same drum I have been beating - there are other ways to sort outages than jumping into solar.

 

 

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@Don and @pilotfish, as well as @Gerald_db on another thread has said this now, and I've also said this before, the nice-to-have part. Sometimes we ask the wrong question. It isn't "what is it worth", it is "what is it worth TO YOU".

Sometimes, you get that unexpected windfall, maybe a SARS tax payback or something... money for mahala so to speak, and just blowing it on something that makes your life better is the most sensible thing in the world.

:-)

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It "helps" to have never had eskom in a rural setting. The money saved on eskom installation and line charges subsidises the off grid solar. @pilotfish is right about KZN. We often have 3 to 4 days rainy days in summer. This means that we need that many days of autonomy. I have run my generator at least 4 times last summer. I am not technical and i have found that there is a steep learning curve and it takes a lot of management. On the plus side having power when everyone else is bleating on the whatsapp group is priceless. 

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13 hours ago, pilotfish said:

You see now - TTT just got everyone realizing that they are on a fools errand and then you cock it all up by showing them real ROI.

The investment guru's say that for every R4000 pm required in retirement you will need R1mil in the bank (at budgeted 5% draw down) - so if you are saving R2000 a month then it is like you have just deposited R500k with Alan Gray - not too shabby! Of course the looming battery bank replacement may have the same effect as heart transplant surgery for the average pensioner!

But keep in mind that part of that saving was because of the Reduction of consumption , ie @Don had to change is power consumption habits so that his lifestyle could fit in with his solar system.
So the theory is if you are considering going off grid you would most likely look at a 5,4,3 setup ( 5Va Inverter , 400ah Batt Bank , 3kw Panels :))

BUT to be able to run that system you will have to reduce your consumption to about 8 kwh per day ( Working on my stats about 2kwh per night and 6kwh per day)

Let's work on 10 kwh per day - at current Grid rate of R2.00 per unit a 30 day month would cost you R 600.00 if you are full on grid only.
The cost of setting up 5,4,3 system is Roughly R 80 000. Hence why most guys will agree that you will be hard pressed to get a ROI on full off grid system IF you have Eskom available AND your are not living on a FARM with fixed line rates. 

@Newbie Charles - If you start to reduce your consumption you might find that 80% of your consumption is running on about 400w (which is still high) and seeing that you are considering running a split system , If you look at running a 1.5 kw system it could account for 80% of your load but will be a lot cheaper that catering for a full off grid system.

Bottom line spend a month or two determining what your loads look like even if you get a , not so popular , effegy meter once you have enough data  you can make a informed decision as to where you are going to spend your hard earned cash :) .

On the other hand if you won the lotto , gaan vir goud  and stuff ESKOM!.... 

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So to underline TTTs point above, if you are spending a lot of money on power, spending a lot  more on on solar will not solve your problem. Change your consumption habits firstly,  and solar may not even be necessary .

I am off grid because the sums worked, no other reason, the eskom line fee made it feasible, after all other savings had been made.

And PaulF is spot on with the 543 story, that works in the off grid situation 100%

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But also, knowing that you will never pay eskom a cent ever again is maybe it's own reward? An off grid system is the ultimate pre-paid. Eke as much life out of your batteries as you can,  and live off the land.....

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listening to what you have and what you want, have you considered adding 12v lights in your house??? We did this a while ago and added 2-8 down lights in each room and added a whole heap of outside lights as well. All running from a 120watt 12v panel, 150am/h battery. The key here was keeping it all 12v. That way, your wiring is way cheaper, you don't need an inverter. We do still have ESKOM lights in the house, we have just run a 12v system next to it. Total cost of running about 30 odd lights.........was under 10k.

I last used as ESKOM light in my house over a year ago. 

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On 6/14/2017 at 1:11 PM, flatfourfan said:

 have you considered adding 12v lights in your house???

 your wiring is way cheaper,

Technically the current drawn by the lower voltage lights of the same wattage will be higher than the mains lights - to minimize losses in the cabling, the cable for the low voltage installation should be thicker and therefor more expensive.

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1 hour ago, superdiy said:

Technically the current drawn by the lower voltage lights of the same wattage will be higher than the mains lights - to minimize losses in the cabling, the cable for the low voltage installation should be thicker and therefor more expensive.

True, but then people often run <10W lamps, which means that whatever cheap mains wire they already had (capable of 15 amps or so) is perfectly suitable, so it does work out cheaper. But yes... you did emphasise the same wattage, so absolutely agreed.

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On 6/15/2017 at 2:01 PM, superdiy said:

Technically the current drawn by the lower voltage lights of the same wattage will be higher than the mains lights - to minimize losses in the cabling, the cable for the low voltage installation should be thicker and therefor more expensive.

Understood, but I'm not running the same wattage as what we had before.......my biggest light in the house pulls 3 watts. 

 

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8 hours ago, flatfourfan said:

Understood, but I'm not running the same wattage as what we had before.......my biggest light in the house pulls 3 watts. 

 

...ignoring power factor and losses and efficiency...

3 watts on 12V => 3/12 => 250mA

3 watts on 220V => 3/220 => 13mA    

Even if you replaced a 50W incandescent bulb with a 3W LED lamp: 50 watts on 220V => 50/220 => 227mA - the 50W 220V lamp actually still required thinner wiring as the 3W 12V lamp...

Normally you would use 1mm2 or 1.5mm2 wire for lights; it will easily feed say 8 x 50W (400W) downlights => 400W on 220V => 1.8A on one light circuit.  If you replace those 50W downlights with equivalent LED downlights, you'll have to use at least 5W lamps to get a similar amount of light => 8 x 5W (40W) on 12V will draw 3.33A, almost double the current of the 220V lamps and you might start to think about using thicker wiring.

Just an example...

 

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I am not sure what the problem is.  It is only the negative which takes the full Amp load.  Every circuit on the positive is on a separate line.  The capacity of the 1.5 sqmm cable is approximately 16 A and I'm not even close to it. My circuit breaker is only 10A, if I have any issues then it will go first. Thicker wires will reduce voltage I agree. 

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On 4/22/2017 at 8:05 PM, Don said:

I agree. I cannot justify any of my installation cost, inverters, batteries, solar panels, or solar tracker. Looking at the figures, I should be on Eskom every day of the week, 24/7. The day it becomes viable, I probably would not have the money to install it. 

I will probably never recover the cost of my installation, unless I live another 25 years and refuse to move to another house.

I just know my electricity bill has come down from R2500-R3000 a month to R200 (R176 to be exact), but if Eskom rates shoots through the roof in the next 3-5 years or Koeberg or Medupi Power station explodes tomorrow, or we start load shedding again, it will not affect me. Life will carry on as normal in my house. 

Our cost came down from about R1800, in 2012, to R250 in summer and R300 in winter currently. I still need to put some insulation in the roof for winter months... Not a big ROI, but I had spare cash. And my wife's home office doesn't suffer any downtime anymore - which turned my ROI into an almost instant winner!

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14 hours ago, flatfourfan said:

I am not sure what the problem is.  It is only the negative which takes the full Amp load.  Every circuit on the positive is on a separate line.  The capacity of the 1.5 sqmm cable is approximately 16 A and I'm not even close to it.

The problem is that for the same wattage lamp on 12V compared to 220V, you'll need thicker wire because the current draw is higher, so your initial statement of "your wiring is way cheaper" is incorrect and misleading and might confuse people not that familiar with the subject.

14 hours ago, flatfourfan said:

Thicker wires will reduce voltage I agree. 

This statement is also incorrect. Thicker wires of the same material (e.g. copper) will have less resistance and therefore will reduce the voltage drop across the length of wire.

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8 hours ago, superdiy said:

The problem is that for the same wattage lamp on 12V compared to 220V, you'll need thicker wire because the current draw is higher, so your initial statement of "your wiring is way cheaper" is incorrect and misleading and might confuse people not that familiar with the subject.

This statement is also incorrect. Thicker wires of the same material (e.g. copper) will have less resistance and therefore will reduce the voltage drop across the length of wire.

Yup. If I was running the same wattage I agree. But I'm not running the same wattage globes, which I've said a few times already. 

As for the voltage comment... I noticed now that I left out the word drop. My bad. 

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