Hello from Randfontein, South Africa.

[Stephen Palos]

Good day all.
I live on a small farm of about 30 acres, just outside a town called Randfontein, about 50km west of Johannesburg.

Our local, state owned power utility has been destroyed this past decade by such massive corruption it is beyond comprehension. From being one of the worlds lowest cost power producers, with excess capacity it is now more often off on what is called rotational load-shedding than up and running. If our economy was not equally destroyed there'd certainly be no capacity whatsoever to meet demand! Power prices rise annually at between 8 and 16%. I want to be totally free from this grid!

Five years of reading and asking, and now I want to start the process. Over time I will certainly ask many questions on these various boards and share my experiences and learning curves as I go.

 

[Steve_S]

Welcome to the forum. We have many members from right across Africa here, quite a few from South Africa too ! Lot of folks are "fed up" to be polite...

Take your time, ask questions, consider options carefully but most importantly, do not buy ANYTHING till you have a plan and know where you are going and how you are going to get there. Impulse Purchases are 90% a waste of good money.

The worst this is when someone shows up here and says: I bought this, that and that plus this, so now how do I put to together and make it work.
Lot of times, they get a Huge Battery & very little charging panels... ie: 24V/280AH battery with 2 100W/12V solar panels... DOH ! Never going to work.

Have fun & Good Luck.

 

[Stephen Palos]

Thanks Steve. Yes, I agree. You won't struggle to convince me on this point. Obviously, I will be locked into South African suppliers, but there are many and some are long-standing and I have confidence in them.

I have been advised that my borehole (water well) should be totally stand-alone, with own panels and solar controller to the pump. Although to me this seems to create a certain redundancy or over-kill, and I would prefer to have that capital doing other things too, I am learning to live with the concept and will simply use the additional pumping time to create a nice fishing pond (my well has more than adequate water for this)

I will start asking specific questions on appropriate boards in due course

 

[rin67630]

I live on a small farm of about 30 acres, just outside a town called Randfontein, about 50km west of Johannesburg.
Power prices rise annually at between 8 and 16%. I want to be totally free from this grid!

Are only the power prices rising or also the fixed part?
Since you already have a grid connection, think about it: on-grid solar, even with an unreliable and expensive provider is always better as being completely off-grid, where you must rely on batteries for everything.

 

[Stephen Palos]

Are only the power prices rising or also the fixed part?
Since you already have a grid connection, think about it: on-grid solar, even with an unreliable and expensive provider is always better as being completely off-grid, where you must rely on batteries for everything.

The fixed part escalates at the same rate, and on my current consumption this makes up nearly 50% of the bill. I could improve this ratio as I do have an overly large supply because the property used to house a poultry farm and abattoir, but even downsizing would set the fixed costs at about 35% of the bill. But the biggest problem is that our utility (Eskom) is really on a downward spiral and escalations are going to get much worse still. They have been deliberately raising fixed costs vis-a-vis consumption prices for years in order to receive revenue for no product actually delivered. It's a national crisis. Just Google "Eskom corruption".

I've taken the "not with MY money anymore" approach now...

 

[Hedges]

I have been advised that my borehole (water well) should be totally stand-alone, with own panels and solar controller to the pump. Although to me this seems to create a certain redundancy or over-kill, and I would prefer to have that capital doing other things too, I am learning to live with the concept and will simply use the additional pumping time to create a nice fishing pond (my well has more than adequate water for this)

Starting a large well pump is one of the most difficult loads.
If your grid power is sufficiently reliable, you could just have a water tank and fill it when the grid is up.
To run the pump off-grid, you either need a quality inverter with several seconds surge capacity about 5x the current rating of the pump (enough for "locked rotor amps"), or else a soft-starting pump.

Some Grunfos pumps have a 3-phase inverter drive and draw no surge current. Some run direct off PV.

You should run the pump when sun shines, when battery is full. Better to store water in a tank than electricity in a battery.

I would lean toward a single PV system able to run the pump and everything else. Enable the pump when battery is full and there is surplus PV production.

Don't know your power usage or financial budget. I'm a fan of SMA. You can built a system from 6 kW to 100 kW of battery inverter, and 3kW to 200 kW of PV array & inverter (from 220V single phase to 220/380V 3 phase). They have larger, commercial and industrial systems as well.

 

[Samsonite801]

Just Google "Eskom corruption".

I've taken the "not with MY money anymore" approach now...

I like your attitude on the subject, the best way to fight corruption is to opt out of it, and the best way to opt out of it is to stop sending them your money, then it doesn't matter what they do anymore... If everyone had that attitude, corruption couldn't survive anywhere, because generally, people in the largest quantity are good in nature, where the few bad eggs tend to control the bunch... But they can't operate without the money we give them...

 

[Stephen Palos]

Starting a large well pump is one of the most difficult loads.
If your grid power is sufficiently reliable, you could just have a water tank and fill it when the grid is up.
To run the pump off-grid, you either need a quality inverter with several seconds surge capacity about 5x the current rating of the pump (enough for "locked rotor amps"), or else a soft-starting pump.

Some Grunfos pumps have a 3-phase inverter drive and draw no surge current. Some run direct off PV.

You should run the pump when sun shines, when battery is full. Better to store water in a tank than electricity in a battery.

I would lean toward a single PV system able to run the pump and everything else. Enable the pump when battery is full and there is surplus PV production.

Don't know your power usage or financial budget. I'm a fan of SMA. You can built a system from 6 kW to 100 kW of battery inverter, and 3kW to 200 kW of PV array & inverter (from 220V single phase to 220/380V 3 phase). They have larger, commercial and industrial systems as well.

Thank you. The system I am looking at is

http://microcare.co.za/1-5kw-three-phase-solar-pump-inverter/

Together with nine 335watt panels it would cost the equivalent of US$1350
This will run my existing 1,5kw pump system which delivers about 6000 litres/hour. I do have adequate water storage, probably to cover 5 cloudy days, so I would still have excess pumping capacity which would feed some irrigation for grazing pasture and a pond if there is excess.

Our climate is on the very favorable side for both solar generally, and with clear, dry winters, for timing of the excess pumping time in our dry months, enabling good use for exotic winter pastures. Summer rains generally sort out that season, but dry spells could be easily covered now with "free" water from solar.

If ever I needed to increase the farming needs I'd up-scale to their 5kw unit and run a 3.75kw pump I have in storage. It's overkill for current needs.

 

[Hedges]

So you have a 3-phase well pump? That's great, can use a VFD for no start-up surge.

You should be able to put in a single-phase or 3-phase PV system to run your property, and have that connected to a VFD for the pump. Then the same panels as supply other loads would supply the pump as well. You could turn the pump on or off depending on whether you have surplus PV production, or simply based on battery state of charge.

If the pump works effectively over a range of rpm, varying water volume and power consumption, it could have speed control varied to use exactly the surplus power available. Don't know if that is available as an off the shelf product. If not, could be a microcontroller and DAC monitoring 50/60 Hz line frequency and controlling analog input of VFD. (For a system like SMA which varies line frequency to signal excess power availability.)

On the other hand, just putting in that stand-alone package for $1350 is cheap enough.

 

[mje]

Thank you. The system I am looking at is

http://microcare.co.za/1-5kw-three-phase-solar-pump-inverter/

Together with nine 335watt panels it would cost the equivalent of US$1350
This will run my existing 1,5kw pump system which delivers about 6000 litres/hour.

Hi Stephen,
Do you have an update on what you did? Just joined the Forum but I've had a 5KVA Victron based system with almost 10KW of LiFePO4 simply to beat load shedding. I installed everything. That runs everything - including a 750 watt swimming pool pump and 750 Watt Bore Hole pump (for irrigation only). Only the Geyser and Stove are excluded. Next job is to add PV Panels - after I change my roof to IBR. Looking at Rand Water (the water supply for Pretoria/Johannesburg and surrounds) might be using the Bore Hole as my main water supply! (I live in Pretoria East - oldish suburban area of the city - 10 or so minutes from where Elon Musk came from).
I initially looked at just Solar powering my pool pump but it quickly became obvious I should have one solution to power everything.

 

[RGIvy]

My brother recently disconnected all his boreholes from Eskom and is now pumping water on solar.
It is perfectly feasible ... pm me if you want his details.

 

[Pierre]

Good day all.
I live on a small farm of about 30 acres, just outside a town called Randfontein, about 50km west of Johannesburg.

Our local, state owned power utility has been destroyed this past decade by such massive corruption it is beyond comprehension. From being one of the worlds lowest cost power producers, with excess capacity it is now more often off on what is called rotational load-shedding than up and running. If our economy was not equally destroyed there'd certainly be no capacity whatsoever to meet demand! Power prices rise annually at between 8 and 16%. I want to be totally free from this grid!

Five years of reading and asking, and now I want to start the process. Over time I will certainly ask many questions on these various boards and share my experiences and learning curves as I go.

Indeed. From generating more than 60% of all the electricity generated on the continent of Africa to an empty shell.
Another state owned enterprise destroyed by the cANCer.

 

[mje]

It seems Water is next. The Dams (Val Dam @ 105% full) are full but citizens of both Johannesburg and Pretoria have been told by the Rand Water Board there is a great lack of municipal water. Probably no expansion over the last 25 years, in fact it sounds like the reverse may be true, along with an increased population. People will need power to pump their own water. My borehole has water at 4 Meters, the pump sits at 35 Meters. With Power Shedding promised for the next five years, those with Solar will potentially have the best access to Water.

 

[Freep]

Does anyone use their own water towers there? I ask because that's how my family in Canada does it with our cabin on the lake. We pump the water to the tower during the day and let gravity do it's thing.