Here’s an idea to beat load-shedding - instead of bailing out Eskom, subsidise solar power

elvis_presley

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#81
PS. I have a large domestic solar pv installation in one of the sunniest areas in the country, and many years of experience in running a house off solar. Have been exporting to the grid for six years.
I've only had mine for about a year, but realize now that it's totally different and you get very differing information when you're actually ready to put money down and start running real numbers. You see everything in a totally different light.

How are you exporting to the grid? Are you getting paid for it, or do you just have an old meter that runs backwards? I'm exporting to the grid, but have a newer electronic meter, so don't get any credit for it :(
 

Arthur

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#82
I had my local muni install a four-quadrant meter, so imports and exports are measured. No payment for exports, just set-off in kWh, so nett metering.
 

Arthur

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#86
Thanks. Will follow up in the new year. Once this kicks in, my system pays for itself in about 6 years, instead of 10+. Not that I bought it for that, it's just nice when things pay for themselves :)
Yup. My system is fully cost-recovered.

I posted full details and sample project plan/motivation in the Solar Power Thread on MyBB about five years ago. 12kW 55-panel array through three Outbacks to an MLT Drives Power Star II hybrid bi-di grid-coupled inverter, with 48 batts. Run everything, incl pool, irrigation, etc, etc. Most months my nett grid consumption is zero.
 
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lsheed_cn

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#87
Helped design a house in Montagu in 2012 using 100% solar. Plans were held up 14 months as municipality was told by Eskom to hold off on approval since there would have been no electricity connection

Owner went to see Eskom in Worcester and was given a variety of excuses why the idea would not work. He was told that "we do not like the idea that you appear not to be supporting us". He could not get a straight answer to the question that Eskom were trying to compel him to use Eskom power. The compromise at the end was to provide a service up to the boundary, but not connect it

City of Cape Town not much different. Fellow in Scarborough has gone off the grid and is harassed by City officials. They turned down his registration on the grounds that there is no earth leakage on some portions of the installation which are not usually included in a mains supplied house
I'm that vicinity more or less (+-30km away) and I'm offgrid without issues.

Built from scratch on part of old Solole, no electricity on the plot, and have run offgrid since day one.
No-one from CoCT has hassled me to get electricity.

Water is a rip off though, the original piping was 50mm, so wasn't changed, and now getting raped for 650+vat a month in having water available, before I even use it. I have been to Plumstead to complain, but apparently I'm one of many many many in the same boat, and we need to wait, while CoCT rips us off monthly.

I haven't signed off my build yet though (as I'm building a larger main house at the back of the plot), although still living here intermittently.

Was going to spring for some Lithium batteries this time, but the 2nd hand Dead Acid (12/220Ah x 4) I bought and literally just installed yesterday seem to be good, so will wait till next visit.


Battery pricing has dropped nicely for LFP, to the point where Dead Acid doesn't make sense for an offgridder like me.
 

Sinbad

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#88
Why? Wouldn’t they make the same profit and simply pay those feeding back into the grid (at a much lower rate) instead of Eskom?

It should be MORE profit for municipalities but less for Eskom.
Nope. I for one wouldn't feed back into the grid at the price they pay. Not worth my investment in capacity.
 

Arthur

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#89
Nope. I for one wouldn't feed back into the grid at the price they pay. Not worth my investment in capacity.
Agreed. Which is why we're unlikely to see nett metering in SA. At least not before the Great Devolution, which follows the Great Collapse.
 

elvis_presley

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#90
Nope. I for one wouldn't feed back into the grid at the price they pay. Not worth my investment in capacity.
Until you actually come to buy your panels. You'll need to get quite a bit more than is needed, because you have to assume it won't be sunny clear skies every day. So what are you going to do with the extra capacity on sunny days? I have a 5.5KW installation, and when I'm away at work on sunny days, it's sometimes got 4.5KW+ extra capacity.
 

supersunbird

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#91
It is a good idea, but it fails to mention several other issues...

1) The system basically has to be replaced every ten years (in an optimum scenario).
2) It takes more income away from Eskom and local municipalities thereby further endangering their economic viability.
3) If it incorporates a battry backup system, then it can take up some space and also increases insurance risk due to possible fire risk.
4) Theft of solar panels and electrical equipment is a high possibility in South Africa
5) Governments around the world have shown a higher propensity to tax such installations (due to decreased income) rather than subsidise such installations. In fact, Cape Town is trying to do this very thing, but requiring registration and licensing.
6) Etc.
At the moment Eskom (as it is being run) is threatening the whole countries economic viability. Will they change how Eskom is being run?
 

Swa

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#92
What you say makes total sense and I'd agree without other knowledge, but I've been at both IS and Teraco datacenters during load shedding, and both times they had their generator running BEFORE load shedding kicked in.

The price of diesel is inconsequential compared to them starting to trigger SLA failures. Why take a chance?
No generators are a precaution as well as to power what's not connected to backup power. Just because it's on doesn't mean power is necessarily being drawn from it. It will scale down and throttle if less power is drawn. Depends on how it's configured but either way it doesn't really matter as it's high grade and can deep cycle thousands of times.
 

elvis_presley

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#93
No generators are a precaution as well as to power what's not connected to backup power. Just because it's on doesn't mean power is necessarily being drawn from it. It will scale down and throttle if less power is drawn. Depends on how it's configured but either way it doesn't really matter as it's high grade and can deep cycle thousands of times.
My point stands. It's not expensive in the context of things.

Edit: Besides - why would they buy enough batteries to keep the datacenter up for hours, when diesel would be a fraction of that price? Datacenters are usually already fed by 2 grids, minimizing the risk. The generator's just the 3rd power source. Your solution isn't making sense.

I recently did the costing for a solution for an office park; R1.5m+ for batteries to hold it up for 3 hours, R250k for a generator. That buys you diesel for a LOT of load sheds! Generators are cheap to buy, run and maintain for a business, they pay themselves back in no time in potentially lost productivity.
 
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Swa

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#94
My point stands. It's not expensive in the context of things.

Edit: Besides - why would they buy enough batteries to keep the datacenter up for hours, when diesel would be a fraction of that price? Datacenters are usually already fed by 2 grids, minimizing the risk. The generator's just the 3rd power source. Your solution isn't making sense.
My point was never that it's expensive. It was claimed that they don't run them flat because there's generator power, but we don't know if that's the case.
1. Once you've already purchased the batteries it's more economical to use them rather than burn extra diesel.
2. It's irrelevant how much they're used as they are high end and tested to last thousands of full cycles.
 

elvis_presley

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#95
1. Once you've already purchased the batteries it's more economical to use them rather than burn extra diesel.
If you got them for free, then yes... but my point is - why would you buy them in the first place? For occasional usage like we're discussing, they become an insanely expensive source of power over the long term. Generators last decades if treated right. They're a very cheap source of power.
 

Eat my shorts

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#96
It's a damn good idea but remember that you have to get that half witted, corrupt government of ours to buy into the scheme, and if they cannot exploit the system to benefit their greedy, extravagant ways and lifestyles, that just ain't gonna happen.
They bit the e-toll scheme Hook line and sinker.
Even if it falls flat on there noses....again. at least every resident will be self efficient by then
 

SauRoNZA

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#97
You still lose the income from the people who now use solar and you end up paying them to do it as well.


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Yea, but you would likely lose them anyway and get nothing from them otherwise.

Now you get some benefit back.
 

Jaws677

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#98
If you got them for free, then yes... but my point is - why would you buy them in the first place? For occasional usage like we're discussing, they become an insanely expensive source of power over the long term. Generators last decades if treated right. They're a very cheap source of power.
Correct
But generators arent always allowed
 

Swa

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#99
If you got them for free, then yes... but my point is - why would you buy them in the first place? For occasional usage like we're discussing, they become an insanely expensive source of power over the long term. Generators last decades if treated right. They're a very cheap source of power.
Whether you paid for them or not is irrelevant. You have them so you might as well use them fully instead of generator capacity. Diesel isn't cheap. I'm not saying it's the case but it would be cheaper to use the stored capacity before using the generator. It's not an either you use the generator or the battery scenario here as generators either throttle down or up to provide the required power.

Yea, but you would likely lose them anyway and get nothing from them otherwise.

Now you get some benefit back.
Whether you get something from them or not depends on if you enable that ability. But subsidising them to no longer use your product is shooting yourself in the foot twice as you still lose income from them.
 

SauRoNZA

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Whether you get something from them or not depends on if you enable that ability. But subsidising them to no longer use your product is shooting yourself in the foot twice as you still lose income from them.
Eskom shouldn’t be a for profit company anyway.
 
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