Planning your own Solar Power System

I've been eye'ing the same inverter as the one the original OP mentioned. It's very decently priced, and absolutely great in terms of features. But I'm still very big in two minds over this solar thing...

A decent sized 6KVA or even 10KVA UPS, with additional batteries are FAR cheaper in terms of overall cost when compared to PV Array, Inverter, and Batteries.

If you want a redundant source of power (i.e. no load shedding), a UPS + Batteries, or a UPS + Gennie, is still far cheaper than going solar. If you however want to reduce your electricity usage (i.e. save monthly), then IMHO Solar will become viable (over 5 or 10 or 20 years depending on usage and amounts invested in the system), but the amounts of batteries required makes the costs astronomical.
 
A UPS is always the better option because it has a built-in battery charger and an automatic controller to detect power failure. This works well in computer installations provided the eletrician knows how to install a 'clean power line'. Most electricians don't do it right and that results in heaters and kettles being plugged into the UPS.
 
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This looks like the best option. A mains/gererator changeover switch is simpler than installing 'clean power lines' with red plugs but the Inverter/UPS will be overloaded by geysers etc.
 
russellw1 said:
A UPS is always the better option because it has a built-in battery charger and an automatic controller to detect power failure. This works well in computer installations provided the eletrician knows how to install a 'clean power line'. Most electricians don't do it right and that results in heaters and kettles being plugged into the UPS.
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Very true - but the same would hold true for Solar inverters and batteries as well. In layman's terms, the Solar Inverter is at the end of the day just a glorified UPS that uses a different means to charge the batteries. Heaters, kettles, geysers, anything that draws huge amounts of current will drain the batteries quickly, UPS or not.

I'm talking basically from a pricing perspective only at this stage. Installations can go wrong either way (Solar or UPS).

Peeps need to clearly understand precisely WHAT it is that they want to achieve, and look at ALL the options in the process - that's all I'm saying

PS:
10KVA UPS: 20K
12KVA Generator (incl. Auto Start & Auto Change Over): 50K
 
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I think people look at this whole issue with different objectives in mind for different problems:

If the problem you want to solve is - "how to survive power interruptions", and your objective is to spend the least amount of money and effort to solve the problem, well then you cant really beat a small cheap generator. It will provide more than enough power and its quick and easy and relatively cheap to install the necessary change over/isolating switch etc.

If the problem is - "how to survive load shedding without annoying the neighbours with a noisy smelly generator", and your objective is least amount of money, then a few batteries and an standby UPS or inverter might be the solution.

Neither of the above two options is going to save you money though. They are lowish initial cost but you will have to pay for fuel in the case of the generator and in the case of the UPS, you pay for the inefficiencies as well as periodic battery replacement which means you use more electricity than you would have before to accomplish the same thing. So in both cases your month bill probably goes up overall.

If your objective is to simply save money, well then then you need to understand your consumption behaviour and start systematically identifying ways to consume less.

If your objective is to become self sufficient at the lowest cost of ownership, then solar power/heating tends to be the best option in the long run, because we are blessed with plenty of reliable sunshine. At current equipment prices, this can also mean you save money in the long term, depending on a few factors. But the upfront cost is high, especially if you go the big bang professionally installed approach - which is why I think that for many people maybe the best approach is to start small and incrementally increase the scope of the project.

So it all depends on what exactly you are trying achieve?
 
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In places north of us where they only get a few hours of power a day, I hear that UPS's are quite common because the power charges the batteries and then the UPS takes over when the power fails. Some like Powerman can have external batteries for long backup time. A generator compatible option would be a good idea otherwise something like a 6kVA UPS charger will overload the smaller ones and the inverter bypass might kick in and add to problems for the gen.
 
What to do when you live in a complex and they don't allow solar panels, generators and such. I like the goalzero solar generator/battery thing they sell. I could just leave it plugged it and use it as a battery backup for small stuff but not sure where to get it or something similar in Gauteng.
 
ciscoyeti said:
What to do when you live in a complex and they don't allow solar panels, generators and such. I like the goalzero solar generator/battery thing they sell. I could just leave it plugged it and use it as a battery backup for small stuff but not sure where to get it or something similar in Gauteng.
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I must say that if that is the case then the body corporate are morons. Might it not help if you had a meeting with them regarding the issue?
 
ciscoyeti said:
What to do when you live in a complex and they don't allow solar panels, generators and such. I like the goalzero solar generator/battery thing they sell. I could just leave it plugged it and use it as a battery backup for small stuff but not sure where to get it or something similar in Gauteng.
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I can understand banning generators, they're horrible things, but solar panels?
 
The_Mowgs said:
I must say that if that is the case then the body corporate are morons. Might it not help if you had a meeting with them regarding the issue?
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maumau said:
I can understand banning generators, they're horrible things, but solar panels?
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I had the "its will be defacing the complex" comment, then I mentioned that is not a valid excuse. Anyhow, the issue now is who would be responsible for the panels etc if something goes wrong (and that includes insurance). Body corporates are responsible for anything outside the unit. So we need to get our documents right and it needs to be decided at an AGM where everybody votes.
 
Nefertiti said:
I had the "its will be defacing the complex" comment, then I mentioned that is not a valid excuse. Anyhow, the issue now is who would be responsible for the panels etc if something goes wrong (and that includes insurance). Body corporates are responsible for anything outside the unit. So we need to get our documents right and it needs to be decided at an AGM where everybody votes.
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Correct me if I'm wrong but if panels are placed on the roof, doesn't it form part of the unit?
Or if you don't/can't put them on the roof, putting the solar panels on an angled metal-panel on top of a pole, fixed to the wall or through the roof, it still forms part of the unit and thus is the responsibility of the owner?

(On a side note, the metal-fixture on a pole through the roof is gonna be what I'm gonna do when finances permits, as my roof is not north-facing).

-G-
 
Gallderhen said:
Correct me if I'm wrong but if panels are placed on the roof, doesn't it form part of the unit?
Or if you don't/can't put them on the roof, putting the solar panels on an angled metal-panel on top of a pole, fixed to the wall or through the roof, it still forms part of the unit and thus is the responsibility of the owner?

(On a side note, the metal-fixture on a pole through the roof is gonna be what I'm gonna do when finances permits, as my roof is not north-facing).

-G-
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I've been told that the from the outside layer of bricks outwards and the roof is the responsibility of the body corporate. Attaching a solar panel would by default make it the responsibility of the body corporate if no other decisions have been made. Thats my understanding from what various people have told me. I have the same issue as yours where my roof is also not north facing, so either a metal setup on my roof to raise it or it lands up on my neighbors roof. My neighbor doesnt mind at all, however the next owners may not be so happy about it. So yea, its working out who is responsible for what and how it will be set up.
 
ciscoyeti said:
What to do when you live in a complex and they don't allow solar panels, generators and such. I like the goalzero solar generator/battery thing they sell. I could just leave it plugged it and use it as a battery backup for small stuff but not sure where to get it or something similar in Gauteng.
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An inverter generator could also be an option. If they won't allow that i'd tell them to go **** themselves.
 
Hi,

I am in the process of building a new house and want to supply my own power, I am looking to push back into the grid, where do I get a meter that will spin back?
 
In South Africa ?

Not going to happen.... no such thing as selling back into the grid.

As for meters spinning backwards ..... illegal and only with old meters :)
 
gimpex said:
In South Africa ?

Not going to happen.... no such thing as selling back into the grid.

As for meters spinning backwards ..... illegal and only with old meters :)
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Already happening. There is a member here(Arthur) that is legally feeding back into the grid. The city of Cape town already have applications on their website. You will need to get a special four quadrant meter installed though.

As for meters going back, that is ideal but being done by some. You can't get these meters anymore.
 
off grid homes said:
Hi,

I am in the process of building a new house and want to supply my own power, I am looking to push back into the grid, where do I get a meter that will spin back?
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Depending on your grid supplier, this might be possible. I've been exporting to the grid for over two years, with full approbation. It's admittedly a pilot project, but it is approved and official. I know of many others.

I posted an outline project plan (for approaching your municipality regarding power exports to the grid) in the Solar Power thread here on MyBB. You can use it as a template for your approach to your grid supplier.

You can install a four-quadrant meter that measures both imports and exports. I have a Landis & Gyr, installed and paid for by my local authority as part of this project. Again, details in the pdf I posted over a year ago.

There are draft regulations for RE SSEGs (Renewable Energy, Small Scale Embedded Generators). It's essential that your grid-tied inverter be SABS approved and certified for things like auto-islanding, ie automatic disconnection when the grid is de-energised. Most of the inverters flooding onto the market in the wake of the present Eskom crisis are not appropriate.

The draft regs also propose thresholds for exports to the grid. You must be a nett consumer, for example. It is also proposed that SSEGs under 5kW not receive credit for exports. My PV array is 12kW.

In short: Yes, it is possible.
 
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Arthur said:
The draft the also propose thresholds for exports to the grid. You must be a nett consumer, for example. It is also proposed that SSEGs under 5kW not receive credit for exports.
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That, seriously, sucks.

It almost makes going grid-tied not worth it at all... I'm a heavy power user in terms of usage, and I require nowhere near above 5kW :cry: Most, would be more than sufficient for grid-tied on the sub 3kW region. It is pretty much enough to make me rethink the entire thing... If local government is going to be that restrictive, I don't even want to start thinking what limitations Eskom will think out for us that do not get our supplies from local municipalities.
 
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