How much you will save by installing solar panels in South Africa

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How much you will save by installing solar panels in South Africa

If you are willing to put up a hefty initial investment, you can avoid load-shedding and reduce your reliance on Eskom using a solar power system.

There are many all-in-one solar power systems available in South Africa which offer enough power and capacity to take your home completely off the grid.

This is from the article:

"A solar power system comprises photovoltaic (PV) solar panels which collect energy from the sun and convert it into DC electricity.

This is then sent to an inverter which uses this energy to charge a battery system. The batteries are then connected to the mains and feed electricity into your home."



I thought it was solar into batteries, batteries into inverter and then into mains?
 

Radioboy

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Just one flaw in the article - maintenance.

Most people i have spoken to had to replace one or more batteries after 5 years.

EDIT for clarity
 

netstrider

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This is from the article:

"A solar power system comprises photovoltaic (PV) solar panels which collect energy from the sun and convert it into DC electricity.

This is then sent to an inverter which uses this energy to charge a battery system. The batteries are then connected to the mains and feed electricity into your home."



I thought it was solar into batteries, batteries into inverter and then into mains?
Generally PV into Inverter's built-in MPPT charge controller and from there the batteries are charged (via solar). If solar not available batteries will charge from mains. Depending on the inverter both solar and mains will be used simultaneously depending on load, or only solar if load does not exceed solar output or solar + battery etc.

If neither solar or mains available then the inverter will use the batteries only to run your appliances. Highly dependent on the inverter type, not all of them are this clever.

Some will use solar only until you exceed the solar capacity, then, instead of blending PV and mains will switch over completely to mains and your solar output goes to waste completely.
 

ActivateD

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R110k is a bargain as installing a 5Kv system cost me R130k (including labour).
 

newby_investor

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Just one flaw in the article - maintenance.

Most people i have spoken to had to replace one or more batteries after 5 years.

EDIT for clarity
For lead batteries, yes.

If you have lithium batteries though, no reason that they can't last 10 years or more if they were specced properly at the install time.
 

ToxicBunny

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R110k is a bargain as installing a 5Kv system cost me R130k (including labour).

Is that an off-grid type system (as in you can run your house largely without an Mains feed if you chose to?)
 

netstrider

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90% of the time most people are probably not even using 2000W, it's when the geyser is running and you're boiling the kettle while cooking dinner or the pool pump is running then suddenly you'll be over 5000W.

Of course, if you substitute the stove with gas that will help immensely, likewise with geyser (or use solar geyser).
 

xrapidx

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90% of the time most people are probably not even using 2000W, it's when the geyser is running and you're boiling the kettle while cooking dinner or the pool pump is running then suddenly you'll be over 5000W.

Of course, if you substitute the stove with gas that will help immensely, likewise with geyser (or use solar geyser).

Yeh, you can see where my geyser runs clearly.
Capture.JPG
 

blowdart18

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They are very optimistic for a 5kw system to save you almost R26 400 a year.
The ROI seems to be incorrect as well, You will probably only pay the system off over 10 years, and then start seeing the saving come through of roughly R12 000 per month.

R154 000 after 10 years with initial system being paid off . . . . . . the figures don't seem to work.

Even then R26 000 per month is roughly 33kw production per day.
 
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ActivateD

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Is that an off-grid type system (as in you can run your house largely without an Mains feed if you chose to?)
They are busy installing everything at my place at the moment so I will be posting soon about my experience and everything. Three quarters of my house will be off the grid except my pool pump, two geysers and oven. Everything excluded will be done in phase two when I totally get off.

I got a single 5Kw battery which cost a fortune but I hope it will be worth it.
 

Sinbad

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They are very optimistic for a 5kw system to save you almost R26 400 a year.
The ROI seems to be incorrect as well, You will probably only pay the system off over 10 years, and then start seeing the saving come through of roughly R12 000 per month.

R154 000 after 10 years with initial system being paid off . . . . . . the figure don't seem to work.

Even then R26 000 per month is roughly 33kw production per day.
The size of the inverter isn't really what will define your savings. The size of your batteries and PV bank, together with your electricity cost, will do that.

My system is 1 year old next week. 3.3KWp panels, 10.25kwh battery. Total solar generation since installation is 4810kwh.

City power peak prepaid rate is R2.16 per kwh
Therefore, total saved so far is R10 389. (Slightly less if you consider the lower electricity price from March to June 2019)
 

newby_investor

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The size of the inverter isn't really what will define your savings.
But you do need to spec your inverter properly according to your load size.

And it's worth getting one that can combine solar + utility if you're using more than the solar can provide, if it switches over 100% to utility then you're wasting the sun.

But otherwise excellent points. What did your setup cost in the end?
 

Sinbad

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But you do need to spec your inverter properly according to your load size.

And it's worth getting one that can combine solar + utility if you're using more than the solar can provide, if it switches over 100% to utility then you're wasting the sun.

But otherwise excellent points. What did your setup cost in the end?
Mine does the blending, it's a full on victron system. R180k or so.
 
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