Backup power for R35k - can it be done?

[Lupus]

For us it's at most 3x 2hr from stages 4 through 8. Schedules above 8 haven't been made public by the municipality so that's all speculative.

Double check those from 6,as ours remains 3 sessions but it goes up 2 hours per session.

 

[bwana]

Double check those from 6,as ours remains 3 sessions but it goes up 2 hours per session.

Double check what? It's been like this for a couple of years. We went from what was arguably the most arduous shedding schedule in the land to one of the better ones. From Stage 5 they start gradually adding industrial areas to the schedule. As a result 4 is the worst residential areas get.

 

[Lupus]

Double check what? It's been like this for a couple of years. We went from what was arguably the most arduous shedding schedule in the land to one of the better ones. From Stage 5 they start gradually adding industrial areas to the schedule. As a result 4 is the worst residential areas get.

View attachment 1294662

Freaking hell wish City Power would do that. We also switched to 2 hours a year ago, the 4 hours could be quite tedious.

 

[maumau]

You can yes... would just be the reverse of the install, so unmount from the wall and remove the inverter wiring from DB. Its not a small job but can be done

Generally Lithiums dont like being on 100% all the time, its actually better to cycle them

Thanks for the info. LURVE the "portability" of this system because I'd prefer to buy the best I can afford, maintain it well and keep it for myself , might be selling my house next year and would get the electrician who fitted it, to move it.

Could see it as an investment, like a car/bike etc.

 

[Mike Hoxbig]

Could see it as an investment, like a car/bike etc.

Cars are not an investment but the analogy is close enough. You need stable electricity just as you need to be able to get around...

 

[maumau]

Cars are not an investment but the analogy is close enough. You need stable electricity just as you need to be able to get around...

Point taken

 

[itareanlnotani]

If you don't mind installing yourself, can be done for 35k

5KW of LFP for 25k, a 5KW inverter can just about be had for 10k (as long as you don't mind an illegal in some area's) axpert or similar axpert "clone".

I'd up the ante a little bit more, and push for a better inverter, but you do what you can do with the budget you have...

 

[fragtion]

I've got a 24v 5kva microcare bidirectional inverter up for grabs for 17.5k if you're interested. It's designed for SLA batteries but I believe microcares can be programmed to work with lifepo. I realise this isn't a classifieds section but just throwing it out there in case this could work for you (or anyone else) drop me a pm if interested

 

[PhireSide]

Thanks for all the feedback so far, much appreciated all. Going to take the evening and sift through here and see what I can come up with and respond to some questions posed to me.

 

[Mike Hoxbig]

Before you take the plunge, get something like an Efergy and measure your base load. Stuff that you need to be on no matter what. This is typically an overnight load while you're sleeping. Also measure your typical evening load with the TV and some lights on. This will inform your choice of battery.

For most people 5kWh would be enough to deal with an extended outage in case the power doesn't come back on time; maybe 6-7 hours on average if you factor in evening + base load. 2.4 kWh might be enough to cover a load shedding slot, but not necessarily to deal with a long outage.

Once you have your battery figured out, measure your peak load. Basically when you're using the most power - this is typically cooking time with microwaves, kettles, stoves etc running at the same time. This will inform your choice of inverter - whether 5kW will be enough or whether you need 8kW.

By doing this little exercise you'll figure out how to get the most immediate benefit to deal with outages, while at the same time getting the best components as you look towards future upgrades to eventually rid yourself of Eskom.

Also where possible, try and become more energy efficient. Stuff like installing a gas/induction stove, replacing your geyser element with smaller one, installing a geyser timer and blanket, LED lights, etc...

 

[PhireSide]

Before you take the plunge, get something like an Efergy and measure your base load. Stuff that you need to be on no matter what. This is typically an overnight load while you're sleeping. Also measure your typical evening load with the TV and some lights on. This will inform your choice of battery.

For most people 5kWh would be enough to deal with an extended outage in case the power doesn't come back on time; maybe 6-7 hours on average if you factor in evening + base load. 2.4 kWh might be enough to cover a load shedding slot, but not necessarily to deal with a long outage.

Once you have your battery figured out, measure your peak load. Basically when you're using the most power - this is typically cooking time with microwaves, kettles, stoves etc running at the same time. This will inform your choice of inverter - whether 5kW will be enough or whether you need 8kW.

By doing this little exercise you'll figure out how to get the most immediate benefit to deal with outages, while at the same time getting the best components as you look towards future upgrades to eventually rid yourself of Eskom.

Also where possible, try and become more energy efficient. Stuff like installing a gas/induction stove, replacing your geyser element with smaller one, installing a geyser timer and blanket, LED lights, etc...

I measured our base load a while ago and it's around 200 - 300w typically, up to around 500w with some lights on and the TV connected.

The biggest consumers are of course the electric geyser and the oven, smaller ones would be the kettle, vacuum cleaner and microwave, and the relatively insignificant ones would be things like cellphone chargers, my NAS, a few Google Home speakers and the like.

I'm fairly happy to leave the oven connected to the mains and bypassing the inverter, as I wouldn't feel comfortable running it through an inverter anyway. On days with load shedding, we can just adjust accordingly and cook on the gas hob or use the microwave to heat up the odd meal.

I'm not looking to give Eskom the boot as that will cost a significant amount, but the idea is just to gain a bit of comfort and reassurance in knowing that we can at least have some form of normalcy in the house when the economic growth hits.

@bwana I wanted to reply to your message earlier but it slipped my mind - it's true that I could get away with running a generator and installing a cutover switch but I'd prefer to bite the bullet and get it over and done with. A generator running late at night won't fly with the missus, and we have no secure place to store it as-is, so we would need to either assemble a wendy or build on to our garage to accommodate that. And don't worry, I have funds earmarked for water tanks and filtration already since that is also pretty high up on the list of priorities. The joys of living in Gqeberha

 

[jdido87]

Been looking at one of these 2. There is a difference between them but I can't recall now. The CoC ain't a problem.

KODAK Solar Off-Grid Inverter VMIII 5KVA/5KW 80A MPPT 48V

KODAK Solar Off-Grid Inverter VMIII 5KVA/5KW 80A MPPT 48V Best suited to smaller domestic systems where no parallel operation is required. Features: Removable LCD control module with multiple communications Built-in Bluetooth for mobile monitoring (Android App is available) Supports USB...

thepowerstore.co.za

KODAK Solar Off-Grid Inverter King with UPS 5KVA/5KW 80A MPPT 48V

KODAK Solar Off-Grid Inverter King with UPS 5KW 48V

thepowerstore.co.za

Pylontech US2000C 2.4kWh 48V Li-Ion Battery

Advantages Vertical industry integration ensures 6000 cycles with 80% DOD. Compact and fashionable design fits in your home environment. Deliver up to 2.4KW* with single module (2.4KWh) - * please note this value is inverter/charger dependant, typically the maximum achieved value is 1.2kW per...

www.sustainable.co.za

 

[TheChamp]

Been looking at one of these 2. There is a difference between them but I can't recall now. The CoC ain't a problem.

KODAK Solar Off-Grid Inverter VMIII 5KVA/5KW 80A MPPT 48V

KODAK Solar Off-Grid Inverter VMIII 5KVA/5KW 80A MPPT 48V Best suited to smaller domestic systems where no parallel operation is required. Features: Removable LCD control module with multiple communications Built-in Bluetooth for mobile monitoring (Android App is available) Supports USB...

thepowerstore.co.za

KODAK Solar Off-Grid Inverter King with UPS 5KVA/5KW 80A MPPT 48V

KODAK Solar Off-Grid Inverter King with UPS 5KW 48V

thepowerstore.co.za

Pylontech US2000C 2.4kWh 48V Li-Ion Battery

Advantages Vertical industry integration ensures 6000 cycles with 80% DOD. Compact and fashionable design fits in your home environment. Deliver up to 2.4KW* with single module (2.4KWh) - * please note this value is inverter/charger dependant, typically the maximum achieved value is 1.2kW per...

www.sustainable.co.za

The King can blend AC and Solar.

 

[Magnum]

My inverter and battery is 40K Ran it as Backup yesterday during No power. Connected Extension lead as output and Bam. Worked as a charm. now that is 24H of UPS power drawing Pc internet and light.

This thing can supply Geyser and electric Stove simultaneously. I'm sorted. Just going to Connect 8 panels today to start some off grid Function.

 

[rrh]

Thanks for the info. LURVE the "portability" of this system because I'd prefer to buy the best I can afford, maintain it well and keep it for myself , might be selling my house next year and would get the electrician who fitted it, to move it.

Could see it as an investment, like a car/bike etc

If you intend to sell the house without the solar system be very careful to ensure that this information is detailed in any offers.

 

[TedLasso]

Can someone help me with math.

My base load at night (everyone sleeping) is about 650w. If I turn off the outside lights I can get down to about 540w. All lights already LED, etc

So assuming a base load of say 800w and my need to run off battery for 10 hours during the night, how many Hubble AM2 would I require?

Assume Hubble AM2s will be fully charged by solar / grid by evening.

During day, I expect solar to run geysers for 2 hours each. Have smart home automation already managing geyser and pool pump runtimes so those will never turn on at night.

 

[Thugscub]

Phireside take your money and move to a first world country. This **** hole is fusked.

 

[KleinBoontjie]

Funny, I emailed 6 and all 6 emailed me back with quotes within 24 hours.

They blind quote you? Without coming to your house and see how the lay-out is going to be?

 

[jdido87]

The King can blend AC and Solar.

Yeah I read that thread from start to finish at 2:30 this morning. A lot of bickering lol

 

[Tankwa]

That is quite an idea that, to get one that I can hook up to a second one if/when the need arises.

I don't mind doing the labour myself and getting a sparky in to do the CoC either. But at this stage the worst will be hooking up the secondary DB. There's no at heights work required as I'm not putting up solar yet, so it's just focusing on the inverter + batteries + ancillaries for now.

I must do my famous spreadsheeting tonight, and see what combo I can come up with

Better to start small then build up in time.
What worked well for me bought 3 x 3kVA 2400W units
12 deep cycle batteries
9 x 300w panels
I was also thinking of the 5kVA but the problem is if you off grid in the middle of the Karoo and your 5kVA gives in then you sit with no power but if you split you have 2 spare inverters to use.(Bit more expensive)
What I did find with the 3kVA is you can't use 8 x 100amp batteries on one inverter because there is not enough sun hours to charge them and using Eskom power it takes 5 hours at 30amp to get to reach full charge.
The solution I came up with is
1x3kVA inverter 4x 100amp batteries with 3 x 300w panels for kitchen plugs
1x3kVA inverter 4x 100amp batteries with 3 x 300w panels for bedroom plugs
1x3kVA inverter 4x 100amp batteries with 3 x 300w panels for lights
The other reason for 3 inverters is the old model 3kVA only allows 600w PV bypass(Newer models are 1500w) so if you using a 900w microwave you still drawing 300w from your battery bank but if you connect all the batteries together then you get 1800w bypass.