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Posted (edited)
11 minutes ago, Vetplant said:

I think so yes.

But, your solar energy isn't waisted, you can run your loads from the grid and then the solar power goes directly into the batteries to bring them up to charge. Once the solar is strong enough and the batteries have enough charge to manage any fluctuations it flips back to Solar+Batteries

I might be missing something, but what is the concern here?

I'm arguing with my neighbor ????

Basically how our system works (victron) is that you can run of battery (battery/solar) and if use more load than batttery(solar) can give,  it starts pulling the shortfall from grid, this is nice if you have small inverter and your geyser goes on, thuss you still run of solar and only small amount from grid.   , It seems like the "off grid kodak" will fall over to grid, heat geyser from there, and once load is down again then only go back to battery (solar).

(geyser just example load that runs long time.. guess any load could be issue if there is marginal sunshine)

 

 

 

 

 

Edited by Karman de Lange
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Posted
1 minute ago, Karman de Lange said:

I'm arguing with my neighbor ????

Basically how our system works (victron) is that you can run of battery (battery/solar) and if use more load than batttery(solar) can give,  it starts pulling the shortfall from grid, this is nice if you have small inverter and your geyser goes on, thuss you still run of solar and only small amount from grid.   , It seems like the "off grid kodak" will fall over to grid, heat geyser from there, and once load is down again then only go back to battery (solar).

(geyser just example load that runs long time.. guess any load could be issue if there is marginal sunshine)

 

 

 

 

 

Ah. 

My batteries can deliver all 5kW of power that the inverter is rated for. Go over that and the entire system trips. You switch everything off and restart from scratch, making sure the power loads are switched off. 

My solar geyser(3kW boost element) does not run off the inverter, but directly from the grid, as otherwise that would leave very little headroom for any other major load before it trips. Stove/Oven circuit is also directly linked to grid. 

A future upgrade could be replacing the element of the geyser with a 1.5kW one and swapping the electric stove for gas. But for now, we are happy to start up the Cadac if we need to cook during loadshedding. 

Posted (edited)

ok, brilliant.. thanks

Our whole house is behind the inverter.. the geyser's relay just gets power from grid(have "timer" on this power line for on/off), so if grid fails, relay cannot go on.  very crude method of making sure can run of the solar if need be (manual switch on), but won't be on by accident if grid trips.

the AC's etc just gets switch off with the HA when grid fails, but they hardly draw power once rooms at temp (inverter types).

 

 

Edited by Karman de Lange
Posted
8 hours ago, Vetplant said:

I'm running this:

https://thepowerstore.co.za/products/kodak-solar-off-grid-inverter-vmiii-5kva-5kw-80a-mppt-48v?variant=31599177695294&currency=ZAR&utm_medium=product_sync&utm_source=google&utm_content=sag_organic&utm_campaign=sag_organic&utm_campaign=gs-2018-09-19&utm_source=google&utm_medium=smart_campaign&gclid=Cj0KCQjw8IaGBhCHARIsAGIRRYoUcw8f6C2OHhw_eeTRBQQVC7uahk2xa3Q2EoUuta0NtLFTS6JUB4YaAkBTEALw_wcB

 

So, according to the description it is Off-grid.

Practically, it utilizes Battery+Solar together to get to the load level if the Solar itself isn't enough. It will only switch to Grid if you tell it to or if it hits the threshold at the bottom of the battery capacity you set it up to.

Not an issue at all,  not for me anyways.

My power bill for last month was R40.

This current month will be significantly more in terms of costs with the colder temps and a bunch of cloudy days. But I have not had a moment of power outage due to loadshedding, which was my main objective with WFH being a reality.

Guys i need help with this. Im no sparky. I cant work like this (i work from home). If i understand correctly, get that kodak inverter, some batteries, possibly connect some solar panels if my budget allows and then get a sparky to connect it all up? I dont need major appliances to run off grid, but if its feasible why not? 

Posted
4 hours ago, gemmerbal said:

Guys i need help with this. Im no sparky. I cant work like this (i work from home). If i understand correctly, get that kodak inverter, some batteries, possibly connect some solar panels if my budget allows and then get a sparky to connect it all up? I dont need major appliances to run off grid, but if its feasible why not? 

It just boils down to cost ...

 

If everything at home is used the total electrical load could potentially double or even tripple the cost of the system.

 

Thus the ideal approach starts with:

1. Analysis and measurement of your electrical loads.

 

2. The next step should consider energy efficient appliances, lights etc ... this has long term energy benefits.

 

3. Now the difficult step ... determine what you consider essential loads, ie what you want/need to keep running during load shedding.  This determines the inverter size, and to some extent the batteries.

 

4. Now your sparkie can start on the split DB setup .. this is needed to ensure the system will only power specific items during a loadshed. Sadly this is a very real practical problem in many homes .... ours is the typical modern townhouse with the DB in the kitchen.  Simply no way to do the split DB here, it would require a very significant rewire to get this to work.

 

5. The topic of power feedback to the grid, or not, is something you need to discus and decide upon with your spakie ....

 

6. As you are in the Western Cape your sparkie should work to the relevant by-law .... only specific brands of products are allowed.  Lengthy application process ... which includes the data of the steps above.

 

What are your primary requirements ?

- keep an office running during loadshedding, pcs only, no hvac ?

- backup power during a loadshed AND long term power savings ?

 

The former can be done under 10k ... the latter is an open checque .....

Posted

Gemmerball worth your while to wade through this load of paperwork ....

 

If you intend doing a legal installation in the Western Cape the installer SHOULD take you through this mountain of paperwork.

 

 

PS - these documents date back to 2018 and earlier, as the Western Cape was an early adopter of PV systems and set about providing a set of rules for this.  The recent national documents basically just repeat this.

 

PPS - reading up on the European systems, and the school fees they have paid, it becomes apparent that "power generation" is just one part of the cost of electricity.  The transmission grid is a significant portion of the final cost.  The scale of private generation in Europe resulted in increased costs for the transmission systems, without the income derived from selling electricity.  THIS is at the hart of the "availability fee" that is being discussed all over the world.  This is an ever evolving topic .... just no way eskom can afford to loose too many paying customers (YES, I share the emotions on this !!)  Just know that the goal posts are still moving, and potential savings is NOT as easy or fixed as it may seem. 

0 Alt energy act.pdf 1 Consultation Paper-Rules for Registration of SSEG.pdf 2 Requiremenst for Samll-Scale Embedded Generation.pdf 3 Application for connection of Small Scale Embedded Generation.pdf 4 Declaration for off-grid SSEG.pdf

Posted (edited)

Just indication on COC/Engineerings sign off prices:

Somerset West:  ~R3100, Stellenbosch ~R 5000

So just work that into the budget if you want to go legal, that is just labour/paperwork ..   Some Engineers insist that you install devices from their "associates " that is not needed. IE, a Friend of mine was told he needs surge protection before sign-off, the quote from the associate was nice R15k, luckily friend new its BS and got sign-off without.

If you just run as backup system, you often don't need sign-off, depending on muni bylaws as its just a UPS.  Some need COC as you wiring it into the DB.

 

good luck with trying to make your mind up ????

 

 

Edited by Karman de Lange
spelling
Posted
1 hour ago, ChrisF said:

 

 

PPS - reading up on the European systems, and the school fees they have paid, it becomes apparent that "power generation" is just one part of the cost of electricity.  The transmission grid is a significant portion of the final cost.  The scale of private generation in Europe resulted in increased costs for the transmission systems, without the income derived from selling electricity.  THIS is at the hart of the "availability fee" that is being discussed all over the world.  This is an ever evolving topic .... just no way eskom can afford to loose too many paying customers (YES, I share the emotions on this !!)  Just know that the goal posts are still moving, and potential savings is NOT as easy or fixed as it may seem. 

 

 

We already pay for availability fee in Stellenbosch (think R200), been like that for years...   Think they saw the writing in the wall ages ago .

Posted

So my new house has 16 solar panels installed with the inverters etc to power the house when it is nice and sunny outside. 
On average a family of 4 with staff and working from home only uses about R300 of electricity from the grid. 

The system is not setup for batteries at this stage and my estimate is around R60k to add the right bits and pieces to get off the grid completely. 

That is a LOT of money but with loadshedding becoming more and more severe with zero chance of it going away any time soon I'm considering it. 

Just need to find a reputable installer now. 

Posted
23 minutes ago, Steady Spin said:

So my new house has 16 solar panels installed with the inverters etc to power the house when it is nice and sunny outside. 
On average a family of 4 with staff and working from home only uses about R300 of electricity from the grid. 

The system is not setup for batteries at this stage and my estimate is around R60k to add the right bits and pieces to get off the grid completely. 

That is a LOT of money but with loadshedding becoming more and more severe with zero chance of it going away any time soon I'm considering it. 

Just need to find a reputable installer now. 

 

I would not go off grid completely , you can get away with lot less by having the grid as backup.. no need for generators , irritated neighbors etc

Posted

Thanks Karma, Frosty and ChrisF,

my first goal is to keep my house lights on and keep my home office running. Thats one wall plug powering my laptop and screen. No printers or anything else. Most of the house lights have been replaced with LED downlighters and the outside lights have also been replaced with LED’s. I would prefer to keep the outside lights on because of security reasons. Oh and the wifi router. My db is in the garage so thats one less issue to deal with. My house is only about 130m2 so its not too big. I dont need more than the aforementioned to be able to work. If its hot ill open the sliding door. If its cold ill run the gas heater. It would be ideal i guess to begin with a system that has the potential to be upgraded as time goes by, but that changes everything as i understand from your comments? In the long run im happy for the geyser to remain on the grid, if i can get the rest of the house to be off grid/grid tied. I only use around 10-12 units per day, no kids or wife around, the wife ducked about 8yrs ago ????

Posted

PS. If it wasnt for Autodesk software being so dependant on an internet connection, the wifi router could have been left out of my estimation. But then again i wouldnt be able to listen to sport while working!

Posted
1 minute ago, gemmerbal said:

Thanks Karma, Frosty and ChrisF,

my first goal is to keep my house lights on and keep my home office running. Thats one wall plug powering my laptop and screen. No printers or anything else. Most of the house lights have been replaced with LED downlighters and the outside lights have also been replaced with LED’s. I would prefer to keep the outside lights on because of security reasons. Oh and the wifi router. My db is in the garage so thats one less issue to deal with. My house is only about 130m2 so its not too big. I dont need more than the aforementioned to be able to work. If its hot ill open the sliding door. If its cold ill run the gas heater. It would be ideal i guess to begin with a system that has the potential to be upgraded as time goes by, but that changes everything as i understand from your comments? In the long run im happy for the geyser to remain on the grid, if i can get the rest of the house to be off grid/grid tied. I only use around 10-12 units per day, no kids or wife around, the wife ducked about 8yrs ago ????

just some general things to concider.

One options are to go lead acid on battery and bank on the fact that lithium will just get cheaper (and quickly).  so use the cheap lead acid for year or two (about how long they last) and invest into lithium or what ever is the latest then.   Lithium dropped by 50% in last 4 years and from what been reading will be about 50% again soon. (if tesla tech gets to the masses).

 

We basicly started with 4 x 120ah lead acid on 1600w inverter so I could keep on working.  added another 1600w invter and 4kw solar about year later.  Those days 1 inverter cost R20k    but payed itself back in lost labour very quickly.  Solar was R12/watt, now R4.50.  

About 4 years ago we installed ~12kwh lithium (home build, so don't know exact capacity) .  Now adding another ~3kwh cause I have the cells.  Shop bought would have been R160k, we paid R8k to build self.  now its about R80k.

This now been installed about 6 years.   Want to add more solar to cover heating in winter, about 2kw short to cover that, but probably only do that next year, hopeing prices will drop more.

 

 

Posted
25 minutes ago, gemmerbal said:

PS. If it wasnt for Autodesk software being so dependant on an internet connection, the wifi router could have been left out of my estimation. But then again i wouldnt be able to listen to sport while working!

 

Internet is another sub-set of issues ....

 

Lots of fibre nodes dont have enough backup for multiple loadshed.  And with more and more people gearing up to work through a loadshed some of these areas goes off air for part of the loadshed.  Some friends struggle with coming back on line as well ...

 

Ironically my old ADSL line is better for this :P

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