Solutions for loadshedding

[Shebeen]

Its a great forums with super helpful people. It does get a bit confusing with all of the info available though.

Not sure on the NMD limit locally but I dont think anywhere but the Republic of Western Cape actually supports SSEG. Most times either a hybrid or off-grid inverter would sit on the grid side and prevent exporting of excess power so Im not sure it would apply.

not even for grid export, just grid tied.

 

it's a serious bummer.

along with the refusal to encourage net-metering.

 

we have a shortage of power (and money) in the country, we should encourage people to install their own.

[Rocket-Boy]

not even for grid export, just grid tied.

 

it's a serious bummer.

along with the refusal to encourage net-metering.

 

we have a shortage of power (and money) in the country, we should encourage people to install their own.

I couldnt agree more, you hit the nail on the head.

 

I have two major issues with government/Eskom.

 

1. You cant make money by feeding excess power generated into the grid, Eskom is short on capacity but they also dont want you to help fix that.

 

2. There are no rebates and in most cases the municipality or Eskom wants to penalize you for not putting up with their inability to do their job. I know there is a tax writeoff that can be done for a business installing solar but it doesnt help individuals.

 

When Eskom is eventually split into its 3 separate companies then their plan is to increase the charge for grid availability and decrease the usage charges. The supposed idea is you would still be paying around the same total each month but they dont want people generating their own power.

 

Honestly the mentality is just nuts, Eskom desperately needs people to pay for all of the power they can generate but they also cant generate enough to satisfy the needs of everyone.

 

I dont want to have to worry about inverters and solar power, I would prefer to just have a normal reliable connection at home but it isnt the case and so I have to start exploring alternatives.

Over the last two weeks I was doing work for an international company which required me to work from 2am - 8am in their datacentres. As would be expected loadshedding happened more than once during that time and my tired batteries on my old inverter cant handle 3+ hours. So that meant I had to try and head into the office at stupidly early hours of the morning just to work.

[fanievb]

Is your geyser just a normal electric 2/3kw unit with no solar?

Those are very difficult to work with because they are pretty much maxing out smaller inverters from the time they get started.

Most often though you would separate out your "essential loads" from your "non-essential loads"

I.e your plugs and lights would be essential and others like pool pumps, geysers etc would be non-essential.

So when loadshedding is going the geyser and pool pump wouldnt work but the plugs and lights would.

 

Its the difference between say a R30k system and a R100k+ system.

 

Solar with "normal" back-up built in (totally solar jobbie)

 

The plan is to split the DB as you suggested.

 

The ideal would be to permanently run essentials (fridges, plugs & lights) off solar and use BCM only for high load items, as and when needed.

 

Our main usage is the pool, fridges, AC and geyser. we have a gas stove/oven which made a significant dent in usage.  

 

But I'm definitely going to look into getting the solar thingy just for the pool (the one you mentioned earlier)

[Wayne pudding Mol]

I run my house, cottage, small pool (tiny office, monstrous bike room mancave plus guest suite) 100 percent off grid, the system was expensive and the house shrunk from the original plan.  That was 4 years ago.  I feel smug a lot these days

 

I hate eskom/municipalities and have tried to give them electricity but they want money for this

 

If I was to advise someone retrofitting a cost effective solution, wire up your essentials (TV, dstv or netflix,  1 fridge, internet, lights, alarm and gate to a reasonable sized inverter, say 3kva and the appropriate battery bank (lithium is best but costs more)  With lithium battery, 3 300w panels this would be around 25k - this should last you through load shedding easily

 

If you have a spare bathroom, install a small gas geyser (battery operated AA) (about 4 grand off the top of my head)

 

My numbers are a bit inaccurate but not far off.

 

Make sure your sparky is decent

 

This 30k is way cheaper than trying to run your whole house off grid as a retrofit

 

If you are building new, get rid of all your old appliances and get inverter technology, full gas stove, shrink your house and go big with the solar system - tell your wife her hair looks better when she drip dries it.

[Rocket-Boy]

Solar with "normal" back-up built in (totally solar jobbie)

 

The plan is to split the DB as you suggested.

 

The ideal would be to permanently run essentials (fridges, plugs & lights) off solar and use BCM only for high load items, as and when needed.

 

Our main usage is the pool, fridges, AC and geyser. we have a gas stove/oven which made a significant dent in usage.  

 

But I'm definitely going to look into getting the solar thingy just for the pool (the one you mentioned earlier)

Ok cool so you are in a good space then. When they do the solar geyser then they put a smaller element in, Im pretty sure its a 1kw unit.

AC is a bit more tricky, if its a traditional AC(non-inverter) then the inrush current on startup is really high and can exceed the inverter capacity. Once they are running though the load drops a whole lot.

 

I have the exact same goal as you, I want to run the majority of my house off of solar during the day, then run the batteries to say 50% at night and if I need more power than that the grid will fill in.

 

The easiest way to achieve that is with a proper hybrid inverter, it gets set to which power source is priority(solar) and which you want to avoid if possible(grid) 

You can start with the inverter and batteries to get through loadshedding and then add solar later if needed. The hybrid inverters are expensive though.

Their main advantage is the ability to blend power sources - battery, solar and grid - and have priorities for each. Very cheap inverters can only switch i.e you have a 3kw load and your solar+batteries only produces 2kw so it switches the *entire* load to grid. A good inverter will first use the 2kw from solar+batteries and then pull the additional 1kw from the grid. It makes a substantial difference that way.

 

The alternative is to use a grid tied inverter with battery backup that gets fed by an off grid inverter. Its really the same thing as a hybrid inverter but can be purchased in phases too.

[Rocket-Boy]

I run my house, cottage, small pool (tiny office, monstrous bike room mancave plus guest suite) 100 percent off grid, the system was expensive and the house shrunk from the original plan.  That was 4 years ago.  I feel smug a lot these days

 

I hate eskom/municipalities and have tried to give them electricity but they want money for this

 

If I was to advise someone retrofitting a cost effective solution, wire up your essentials (TV, dstv or netflix,  1 fridge, internet, lights, alarm and gate to a reasonable sized inverter, say 3kva and the appropriate battery bank (lithium is best but costs more)  With lithium battery, 3 300w panels this would be around 25k - this should last you through load shedding easily

 

If you have a spare bathroom, install a small gas geyser (battery operated AA) (about 4 grand off the top of my head)

 

My numbers are a bit inaccurate but not far off.

 

Make sure your sparky is decent

 

This 30k is way cheaper than trying to run your whole house off grid as a retrofit

 

If you are building new, get rid of all your old appliances and get inverter technology, full gas stove, shrink your house and go big with the solar system - tell your wife her hair looks better when she drip dries it.

That is really awesome, I would love to go fully off grid but the battery cost is too high for me right now. The rest is fairly straight forward with a bunch of panels and a good inverter/MPPT mixed setup.

 

How much did you have to adapt to being battery powered and having to think about what appliances would be on at the same time?

[Wayne pudding Mol]

Ok cool so you are in a good space then. When they do the solar geyser then they put a smaller element in, Im pretty sure its a 1kw unit.

AC is a bit more tricky, if its a traditional AC(non-inverter) then the inrush current on startup is really high and can exceed the inverter capacity. Once they are running though the load drops a whole lot.

 

I have the exact same goal as you, I want to run the majority of my house off of solar during the day, then run the batteries to say 50% at night and if I need more power than that the grid will fill in.

 

The easiest way to achieve that is with a proper hybrid inverter, it gets set to which power source is priority(solar) and which you want to avoid if possible(grid) 

You can start with the inverter and batteries to get through loadshedding and then add solar later if needed. The hybrid inverters are expensive though.

Their main advantage is the ability to blend power sources - battery, solar and grid - and have priorities for each. Very cheap inverters can only switch i.e you have a 3kw load and your solar+batteries only produces 2kw so it switches the *entire* load to grid. A good inverter will first use the 2kw from solar+batteries and then pull the additional 1kw from the grid. It makes a substantial difference that way.

 

The alternative is to use a grid tied inverter with battery backup that gets fed by an off grid inverter. Its really the same thing as a hybrid inverter but can be purchased in phases too.

adding to this - buy a good inverter.  Make sure you get one that can be coupled  - for example I have a little stand alone system in my workshop (woodworking would be exagerating but I can build stuff like decks and houses)  The system can run most appliances but no simultaneously.  When/if cash becomes available I can buy another inverter/battery and panel combo and double up super simply

 

That was a long winded way of saying make sure your sh*t is upgradable

[Wayne pudding Mol]

That is really awesome, I would love to go fully off grid but the battery cost is too high for me right now. The rest is fairly straight forward with a bunch of panels and a good inverter/MPPT mixed setup.

 

How much did you have to adapt to being battery powered and having to think about what appliances would be on at the same time?

We don't think about it anymore - the system is big for us at 8kva and we only have 1 kid.  We don't need ac here.

 

Things we learned early

Iron early during the day and make sure the sun is shining

Goodbye tumble drier

Hairdryers and straighteners are for special occasions girls

Panfried toasted cheese is awesome

You need a regulated gas oven (2w fan)

Get good batteries if you like coffee

think about what you want from the fridge before you open it

small pools need small pumps

heat pumps are great

 

Neighbours don't like it when you have lights and they don't

[splat]

 

If I was to advise someone retrofitting a cost effective solution, wire up your essentials (TV, dstv or netflix,  1 fridge, internet, lights, alarm and gate to a reasonable sized inverter, say 3kva and the appropriate battery bank (lithium is best but costs more)  With lithium battery, 3 300w panels this would be around 25k - this should last you through load shedding easily

 

If you have a spare bathroom, install a small gas geyser (battery operated AA) (about 4 grand off the top of my head)

 

My numbers are a bit inaccurate but not far off.

 

Make sure your sparky is decent

 

I have a 3kV inverter + batteries - it's free standing (with extension cords) at the moment.

Next step is to connect that to the main DB - that's another R 7.5k for sparky to do a bit of rewiring and ad sub DB. That would run lights (with LED bulbs) and selected plug points.

After that, I would like to add some solar panels, but I have no idea of how many and what sort of cost is involved in that.

[Wayne pudding Mol]

I have a 3kV inverter + batteries - it's free standing (with extension cords) at the moment.

Next step is to connect that to the main DB - that's another R 7.5k for sparky to do a bit of rewiring and ad sub DB. That would run lights (with LED bulbs) and selected plug points.

After that, I would like to add some solar panels, but I have no idea of how many and what sort of cost is involved in that.

I'm not an expert and not sure of your batteries but ... 3 x 300w panels = R6000 - possibly a stand to get the angle correct

 

ps expensive sparky

[kosmonooit]

I

 

ps expensive sparky

Splitting a db involves a lot of work: identifying circuits, locating the neutrals, extending the wiring, often adding an external box, new circuit breakers, working to the SANS codes,   and often fixing cr@p work done previosuly;  R7.5k is not bad at all. I charge more.

[splat]

I'm not an expert and not sure of your batteries but ... 3 x 300w panels = R6000 - possibly a stand to get the angle correct

 

ps expensive sparky

 

Ok, so about R2k per panel (+ I probably need a solar charge controller if my Inverter doent have that built in)

Is that a DIY job, or does it also need qualified installers with certification etc?

 

Splitting a db involves a lot of work: identifying circuits, locating the neutrals, extending the wiring, often adding an external box, new circuit breakers, working to the SANS codes,   and often fixing cr@p work done previously;  R7.5k is not bad at all. I charge more.

 

Ja, that's what has been explained to me

[Rocket-Boy]

Ok, so about R2k per panel (+ I probably need a solar charge controller if my Inverter doent have that built in)

Is that a DIY job, or does it also need qualified installers with certification etc?

 

 

Ja, that's what has been explained to me

Pretty much all of the inverters have an MPPT charge controller. Where it gets tricky is that most are grid-tied so when you introduce solar they will most likely turn off when the grid supply goes down.

 

The other downside is that they normally can only switch loads and not blend power as required.

[Wayne pudding Mol]

Pretty much all of the inverters have an MPPT charge controller. Where it gets tricky is that most are grid-tied so when you introduce solar they will most likely turn off when the grid supply goes down.

 

The other downside is that they normally can only switch loads and not blend power as required.

So if this was a back up solution rather than power blending/power saving wouldn't the sparky be able to ensure it kicks in when eskom drops? - like an auto transfer switch

 

A lot of the installers still like a stand alone MPPT charge controller for some reason

[Rocket-Boy]

So if this was a back up solution rather than power blending/power saving wouldn't the sparky be able to ensure it kicks in when eskom drops? - like an auto transfer switch

 

A lot of the installers still like a stand alone MPPT charge controller for some reason

Yes when its just used with battery backup then they operate in UPS mode, but when solar is introduced then all grid-tied inverters have to turn off when the grid is off. Its designed that way to protect technicians working on the lines. Even with the export functions disabled they still behave that way.

 

Im sure the separate MPPT controller is related to brands like Victron keeping those functions separate and being the most popular(most expensive too!)

Ideally if you have a blended solution then having the off-grid, grid-tied and MPPT functions separated makes it a lot easier to make changes in future. It also means less damage in the event of a lightning strike vs an all in one solution like a Goodwe.

[Ispeed_V]

We are also looking at going off the grid totally.

 

Could end up being a costly outlay as we are a family of 4 as well as a self contained cottage that our domestic and her husband and son stay in. 

 

Would also need to run a pool pump (not a small pool) as well as the pump for the borehole.