Interesting price difference between solar with grid backup, and going off-grid

Jan

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Solar power with Eskom grid backup vs going off-grid — surprising price difference

There is a monumental difference in the price you would pay for a solar power system capable of providing around 95% of your electricity usage compared to one that can achieve 100%.

AWPower's managing director and head of operations, Christiaan Hattingh, recently told MyBroadband that, for most households, he would strongly advise against an entirely off-grid solar energy system without Eskom as a backup.
 
I think the point they are saying is that 5% might be an entire week with no genertion. Can you make do without for a week.
 
OK, so why not take the 95% spec and just add a generator? Surely on those odd occasions you need a bit extra, a gennie can pick up the slack. Will also cost significantly less.
Or just be willing to suck it up if the 5% happens to overlap with loadshedding?
 
Electricity at the price of diesel or petrol? No thank you.... and noisy and poluting.
Well the difference between off-grid and 95% is about R300k+. How much petrol can you buy with R300k.
And it is only noisy and polluting if the install was done by an idiot.
 
My system manages 70% of my needs and cost R70k incl a lithium-ion battery
Installed in 2015, it paid for itself last year some time
 
My system manages 70% of my needs and cost R70k incl a lithium-ion battery
Installed in 2015, it paid for itself last year some time
What system are you running?
Is the R70K the 2015 price or the current price?
 
Well the difference between off-grid and 95% is about R300k+. How much petrol can you buy with R300k.
You're not buying petrol once off.
Unless you're American and have trouble living within a reasonable carbon footprint, you don't have to pay an extra 300k to be off grid. Just make sure you have sufficient storage and use gas to cook on / solar geyser. I can absolutely go off grid with another R120k on top of the R150k I spent to start with.
And it is only noisy and polluting if the install was done by an idiot.
Sure you can stick it in a rockwool laden box and add accoustic ducting, but not sure how that deals with the polution.
 
I agree. Just switch off the geyser and the aircon. Problem solved.
In my case I use the gas oven instead of electric and hang clothes up instead of tumble dry. I won't use the aircon of course. The rest is really minimal.
 
You're not buying petrol once off.
Unless you're American and have trouble living within a reasonable carbon footprint, you don't have to pay an extra 300k to be off grid. Just make sure you have sufficient storage and use gas to cook on / solar geyser. I can absolutely go off grid with another R120k on top of the R150k I spent to start with.
O I agree on that, my comment was relating to the prices quoted in the article.
But even so, even at a petrol price of R40/l you would still have about 1000-1500 hours of generator time. Also remember you only use the generator to recharge the batteries, plus even in the worse weather conditions your panels still generate some power. Based on the 600kWh assumption, your batteries should be good for at least 12 hours at a time. So you run the generator to charge the batteries and then switch it off.
Sure you can stick it in a rockwool laden box and add accoustic ducting, but not sure how that deals with the polution.
CO2 scrubbers similar to what they have on power plants, just on a smaller scale for residential use.
 
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Like the 1st reply said, the cheapest and only real solution is to emigrate. All the ROI calculations are flawed since the rules and tariff structures are constantly changing to prevent people from escaping a high household bill via their solar system investment. Emigration is 1st prize. There are no other prizes. You can try to go off-grid and conceal your solar system if you stay, otherwise buy a small eco generator and live with it.
 
But even so, even at a petrol price of R40/l you would still have about 3000 hours of generator time. Also remember you only use the generator to recharge the batteries, plus even in the worse weather conditions your panels still generate some power. Based on the 600kWh assumption, your batteries should be good for at least 12 hours at a time. So you run the generator to charge the batteries and then switch it off.
Either way, it doesn't make sense to pay BP instead of Eskom at the price. If you're in the sticks and Eskom doesn't exist or is down for extended periods regularly, fine, you probably already have a generator. If you have Eskom available... why go off grid?
CO2 scrubbers similar to what they have on power plants, just on a smaller scale for residential use.
Link please
FWIW I'm in agreement that a genny is better than nothing if you don't have options.
 
Either way, it doesn't make sense to pay BP instead of Eskom at the price. If you're in the sticks and Eskom doesn't exist or is down for extended periods regularly, fine, you probably already have a generator. If you have Eskom available... why go off grid?
Yes, this is pretty much where we are. Current prediction is of at least 61 days of loadshedding during the winter months.
Link please
FWIW I'm in agreement that a genny is better than nothing if you don't have options.
 
Like the 1st reply said, the cheapest and only real solution is to emigrate. All the ROI calculations are flawed since the rules and tariff structures are constantly changing to prevent people from escaping a high household bill via their solar system investment. Emigration is 1st prize. There are no other prizes. You can try to go off-grid and conceal your solar system if you stay, otherwise buy a small eco generator and live with it.
The problem is solar vs emigrating is like saying the solution to your car steering wheel vibrating is to buy a boat.
 
"R242,000 for 1,200kWh of consumption."

That is a kukload of energy and I have poor family members that'll spend more than that on a bakkie.
So maybe it's just me, but that's cheap.

If that's a good quality 20 year system it's R1008K PM.... to be completely off grid. No more loadshedding, home value increase etc.

It's a no brainer.
What am I missing here?
 
"R242,000 for 1,200kWh of consumption."

That is a kukload of energy and I have poor family members that'll spend more than that on a bakkie.
So maybe it's just me, but that's cheap.

If that's a good quality 20 year system it's R1008K PM.... to be completely off grid. No more loadshedding, home value increase etc.

It's a no brainer.
What am I missing here?
That's basically my usage, ±40kWh per day.

My system set me back R252k and I'm 100% off grid for 7 to 8 months of the year. From mid April to August my production is less than my consumption with some days being less than 10kwh in solar generation.
 
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