Generator or Inverter for residential use?

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Jan 6, 2020
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If you add batteries in series the voltage will increase by 12v with every battery added (not ideal if you are running 12v only). In parallel the voltage will remain 12v but the available current will increase. Regular battery inspection and maintenance is a must. I have set up to run emergency lights and the TV/ decoder only from inverters / battery / solar panel recharging with two generators (2500w and 6500w) on standby if the power goes down for a long time (to keep refrigerators going). Not ideal but cost effective, and you can buy / add to the picture as funds become available.
 

Speedster

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May 2, 2006
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If you add batteries in series the voltage will increase by 12v with every battery added (not ideal if you are running 12v only). In parallel the voltage will remain 12v but the available current will increase. Regular battery inspection and maintenance is a must. I have set up to run emergency lights and the TV/ decoder only from inverters / battery / solar panel recharging with two generators (2500w and 6500w) on standby if the power goes down for a long time (to keep refrigerators going). Not ideal but cost effective, and you can buy / add to the picture as funds become available.
Only partly true. Decent batteries are 24V or 48V so keep that in mind.
 

Gaz{M}

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Feb 9, 2005
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6,160
We recently had no power for 9 hours and then again for 36 hours a week later. All my batteries, powerbanks, mecer inverter etc. died and my fridges got warm.

I've tried coming up with a plan to at least run fridges (250W+150W+150W) for a couple hours a day and recharge some of the batteries, but it is impossible to do for less than R5000 for a terrible generator or R9000 for an inverter generator or about R12 000 for a battery and pure sine wave inverter. Solar is even more expensive. Seems like too much to spend for a couple of long power cuts a year that will otherwise not be used.

Any ideas?

The pure sine wave requirement for the fridges really blows the budget out the water. Batteries are also now very expensive due to demand and the dollar rate blow out.

I have a 720W Mecer and a 60ah UPS battery. Good for 6 hours of loadshedding but nothing more.
 

thechamp

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Feb 26, 2011
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We recently had no power for 9 hours and then again for 36 hours a week later. All my batteries, powerbanks, mecer inverter etc. died and my fridges got warm.

I've tried coming up with a plan to at least run fridges (250W+150W+150W) for a couple hours a day and recharge some of the batteries, but it is impossible to do for less than R5000 for a terrible generator or R9000 for an inverter generator or about R12 000 for a battery and pure sine wave inverter. Solar is even more expensive. Seems like too much to spend for a couple of long power cuts a year that will otherwise not be used.

Any ideas?

The pure sine wave requirement for the fridges really blows the budget out the water. Batteries are also now very expensive due to demand and the dollar rate blow out.

I have a 720W Mecer and a 60ah UPS battery. Good for 6 hours of loadshedding but nothing more.
If I were you I would hope for the best in terms of power cuts and invest in a good minimum 1000-1500W pure sine wave inverter, it won't solve your immediate problems but you will have taken a step towards a long term solution. You can then save towards a battery to complete your fridge backup solution. Prices will come down if we manage to keep our good run with Eskom on loadshedding.

Having said that R5000 is just too ambitious to cater for a decent solution.

A generator does not make sense to me personally as it is just too much hassle to manage, but it could sort you out in the short term.
 

Daruk

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Jul 18, 2008
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Generators are good low capital outlay options to run your stuff for longer periods at higher per hour cost.
Inverter and batteries are higher capital outlay but ideal for running stuff at way lower per hour cost. If you can afford R100k+ you can run for many hours, if you can only afford R30-50k, expect much shorter run time.
 

The_Ogre

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Proper batteries used for solar (and normal inverter) installations tend to be 48V. 12V would only be used for relatively small installations
That would make your initial statement misleading.

A 12v (actually 13.6v) LiFePO4 battery is much more decent than a 24v lead-acid.
 

RaptorSA

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Sep 2, 2008
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Finally got my setup installed yesterday and today after having to watch it all lie on the ground during the lockdown.
Had some major issues initially but managed to figure it out (ended up using a CAT5 cable to get the BMS to communicate with the battery properly, that resolved any inverter errors).

It's in a 82 square two-bedroom unit next to my kitchen, so I'll probably spend some time in future repainting some of the walls and trunking and maybe mounting a white 250mm pine panel left of it so you don't have to look at the black side view when you walk into the unit and so it blends with the panel room dividers for the living room/home theatre... might even build a "corner closet" of sorts around it since airflow isn't an issue and the place is always a few degrees colder than the surface of Mars.

Noise wise that Growatt is a bit of a hoover like some have mentioned but for now I kind of enjoy the sound since it's like an additional "sense" when running high power consumption devices, no heaters and kettles and it's quiet enough for my taste.

When I've been running it for some time and did all the testing I wanted to do, I'll flip the DB board to mains power mode only and spare the fans, electronics etc. I'll just boot it up every now and again so the battery can charge if it needs to... but we'll see how it goes.

It's a lot of fun to finally be able to run around like an idiot and switch devices on and off to get an idea of what your actual usage is, no more crap spreadsheet calculations based on guesses.

Currently, with most of my lights + LED strip lights on, the WiFi router, fibre router, 55" TV, 2 Xiaomi Android TV devices, network switches and soundbar I'm only using around 250-300 Watts if I don't use the fridge...
Switching out the TV for the projector and 6.2 surround sound speakers get me to about 400 Watts, which is pretty decent I think. My goal was to not go over 500 Watts.. with 400 Watts the max I'd use... funny how my actual usage was in that range all this time.

No idea how long it'll last me, but I have a feeling if I don't use the fridge or unnecessary lights and appliances it might for be for days. That pack has a lot of energy in it for one person... but hey, f**k you Eskom.

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RaptorSA

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Installer? Total price of equipment + installation?
My budget was R50K but with equipment at R46K plus another R10.5K for install I went slightly over.
A similar system with two cool but butt ugly Pylon batteries would have been closer to R90-100K with install.

I'll PM you the guy/company I used if you're interested (Ranburg/Roodepoort region).

It was their first Lithium install but they were bloody excellent at support and I'd gladly pay it again if I could.

I almost tried the install myself at some point but that would have been a really dumb idea, you really need to know what you're doing (at least I can say I was the one who figured out the battery comms issue :))
 

TEXTILE GUY

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Oct 4, 2012
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Finally got my setup installed yesterday and today after having to watch it all lie on the ground during the lockdown.
Had some major issues initially but managed to figure it out (ended up using a CAT5 cable to get the BMS to communicate with the battery properly, that resolved any inverter errors).

It's in a 82 square two-bedroom unit next to my kitchen, so I'll probably spend some time in future repainting some of the walls and trunking and maybe mounting a white 250mm pine panel left of it so you don't have to look at the black side view when you walk into the unit and so it blends with the panel room dividers for the living room/home theatre... might even build a "corner closet" of sorts around it since airflow isn't an issue and the place is always a few degrees colder than the surface of Mars.

Noise wise that Growatt is a bit of a hoover like some have mentioned but for now I kind of enjoy the sound since it's like an additional "sense" when running high power consumption devices, no heaters and kettles and it's quiet enough for my taste.

When I've been running it for some time and did all the testing I wanted to do, I'll flip the DB board to mains power mode only and spare the fans, electronics etc. I'll just boot it up every now and again so the battery can charge if it needs to... but we'll see how it goes.

It's a lot of fun to finally be able to run around like an idiot and switch devices on and off to get an idea of what your actual usage is, no more crap spreadsheet calculations based on guesses.

Currently, with most of my lights + LED strip lights on, the WiFi router, fibre router, 55" TV, 2 Xiaomi Android TV devices, network switches and soundbar I'm only using around 250-300 Watts if I don't use the fridge...
Switching out the TV for the projector and 6.2 surround sound speakers get me to about 400 Watts, which is pretty decent I think. My goal was to not go over 500 Watts.. with 400 Watts the max I'd use... funny how my actual usage was in that range all this time.

No idea how long it'll last me, but I have a feeling if I don't use the fridge or unnecessary lights and appliances it might for be for days. That pack has a lot of energy in it for one person... but hey, f**k you Eskom.

View attachment 844601 View attachment 844605
View attachment 844613
Very very nice ...... very nice indeed sir :)
 

RaptorSA

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Sep 2, 2008
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Very very nice ...... very nice indeed sir :)
Thanks man... :)
By the way, I need to give a big shout out and thank you to @thechamp...

He pointed me to the installation company and the awesome dudes who did it, even though I've been a complete d1ck to him on-and-off for our differing views on political crap, it just shows how little that stuff matters in real-life.

Take this as a thank you, an apology and a lesson learned at the same time.
 

wingnut771

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Joined
Feb 15, 2011
Messages
7,827
My budget was R50K but with equipment at R46K plus another R10.5K for install I went slightly over.
A similar system with two cool but butt ugly Pylon batteries would have been closer to R90-100K with install.

I'll PM you the guy/company I used if you're interested (Ranburg/Roodepoort region).

It was their first Lithium install but they were bloody excellent at support and I'd gladly pay it again if I could.

I almost tried the install myself at some point but that would have been a really dumb idea, you really need to know what you're doing (at least I can say I was the one who figured out the battery comms issue :))
is that the 5kw ufo battery?
 

RaptorSA

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Joined
Sep 2, 2008
Messages
4,486
is that the 5kw ufo battery?
Yeah it's the 4.8 one here:

My guess is they save money on some of the components inside so I'd expect the battery cells to outlast the battery management components if all goes well.

It's one of the reasons I'll probably shut it down when not using, it's basically a permanent fixture now so I'd aim for decades and not years of use (assuming of course it's not ever going to be used for PV, which it might).
 
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