Running a petrol generator vs the cost of batteries compared

Big Rat

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If I interpret correctly what you are saying here, you are putting yourself and your family in great danger by reverse feeding through a plug outlet. Doing that is illegal and render the earth leakage protection inoperative and someone can get killed if toughing a live wire. Do yourself and your family a Favour and have a qualified electrician do a proper connection for the generator
Ok, qualified electrician told us to do it this way for ease of use. been doing it for 5 months now, no hassle. And if you have open live wires laying around the house you have bigger problems than this i would think. :oops:
But thank you, did not know about the earth thing. will chat to the leccie when i see him again about that and how to do a proper linkup
 

wingnut771

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Was also checking this out yesterday, already have a backup for the house but looking for a portable backup option, the LP Gas option is interesting due to it's shelf life vs. petrol.

This is what I could find so far, obviously a rough estimate :

Running a generator with a 3000-watt load for an hour would consume 2.95l of propane.
How many litres in a 18kg bottle? :unsure:
 

rh1

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Ok, qualified electrician told us to do it this way for ease of use. been doing it for 5 months now, no hassle. And if you have open live wires laying around the house you have bigger problems than this i would think. :oops:
But thank you, did not know about the earth thing. will chat to the leccie when i see him again about that and how to do a proper linkup
He connected this:


With the end point connected directly to the inverter, if not for solar, I would connected via a transfer switch to the DB

 

Neuk_

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Likes:

Powerful, can run fridges, microwaves and fridges and I had no issues running LED Tvs, Desktop PC and Laptops. Sevice kits starts from R150 last time I check.

Dislike: Noisy. Chinglish User Manual. Mislabled choke.

Edit: Relatively Cheap: R8995 now, last year this time it was R7995.

That is not an inverter :unsure:
 

rh1

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That is not an inverter :unsure:
Oops, was in a MS Teams meeting, I got this inverter from Powerforum-store:

 

Neuk_

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Oops, was in a MS Teams meeting, I got this inverter from Powerforum-store:


Cool :cool: Same inverter I am looking at but we will have a 15kVa generator.
 

rh1

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Ok, qualified electrician told us to do it this way for ease of use. been doing it for 5 months now, no hassle. And if you have open live wires laying around the house you have bigger problems than this i would think. :oops:
But thank you, did not know about the earth thing. will chat to the leccie when i see him again about that and how to do a proper linkup
Just to add this is the cable they created to connect the genny. It uses 2 x 25 amp plugs which came with the genny:

20220920_113743.jpg 20220920_113750.jpg
 

Neuk_

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What do you want to power with that?

With the generator? It was installed by the current owners of the house, they run just about everything besides the pool when there is load shedding.
 
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surface

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The assumptions made in the article border on ridiculous.

Why stop at 60, 120 and 180 days? Yes at those intervals the costs may be comparable, but generators are an ongoing expense where batteries/inverters are fixed.

Load shedding is not going to suddenly end in 6 months time...

Service costs for generator.
Replacement cost every 5 years for batteries.
Future price of fuel.
Lots of moving parts in this analysis...
5 years for batteries? You sure ?

If I look at geewiz products, they bring up this popup. Chances are that one has to replace 2 batteries every 6 months or even less than that.

1663669537118.png
 
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Mike Hoxbig

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5 years for batteries? You sure ?

If I look at geewiz products, they bring up this popup. Chances are that one has to replace 2 batteries every 6 months or even less than that.

View attachment 1386386
With lithium you're looking at 5 years minimum, even if you cycle it daily. If not it'll be even longer.

Also lead acid can only be discharged up to 50%. Lithium can be discharged until empty...
 

Neuk_

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With 15 kVA you can probably run the neighbour's house and their pool too...

I am generous but perhaps not that generous :unsure: The house, new to us, has two electric geysers excluding the electric geyser in the garage which isn't used, two ovens, two fridge/freezers, under floor heating, CCTv, electric fence, alarm, pool, two fountains, etc. in addition to the usual lighting.
 

Kosmik

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5 years for batteries? You sure ?

If I look at geewiz products, they bring up this popup. Chances are that one has to replace 2 batteries every 6 months or even less than that.

View attachment 1386386
This is a point I was about to type, anything with 200 cycles are so is going to die very quickly with the current level of loadshedding, life would be in months vs years.
 

Kosmik

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Ok, qualified electrician told us to do it this way for ease of use. been doing it for 5 months now, no hassle. And if you have open live wires laying around the house you have bigger problems than this i would think. :oops:
But thank you, did not know about the earth thing. will chat to the leccie when i see him again about that and how to do a proper linkup
Yes, please don't do this, pay the extra R1k or so for a proper cutover switch, you are playing with fire doing a reverse feed.
 

surface

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With lithium you're looking at 5 years minimum, even if you cycle it daily. If not it'll be even longer.

Also lead acid can only be discharged up to 50%. Lithium can be discharged until empty...
5 years is decent then. Depending on cost of course. Is it theoretical or have you actually had lithium batteries that lasted 5 years+

*I am skeptical of geewiz claims now
 

qscwbt

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I have a 7 kw (8.75kva) Generator. I thing it has a 30 or 40 liter tank. its connected to the db board with a switch.
It has the alarm that notifies you if the power comes on.

I have had generator back up for 7 years. I replaced my first one as i bought way to small. Even sold it and made profit.

The current one is probably 3 years old. key start and runs perfect. I replaced the spark plug this year R30 bucks. Oil i just use leftover oil from servicing the car. air filter is washable.

This thing is efficient. I get over a hour on a liter of fuel.

So with it connected to the db board the following will always be on

Outside lights 5 all led
cctv cameras
electric fence
alarm
3 ups
3 fridge / freezers
inside lights
tv
wifi

what i normally keep off but the generator can manage
Geyser. do have solar geyser so if overcast it will come on
Pool pump

MY wife still uses the kettle or microwave as needed.
 

hj007

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I have a 7 kw (8.75kva) Generator. I thing it has a 30 or 40 liter tank. its connected to the db board with a switch.
It has the alarm that notifies you if the power comes on.

I have had generator back up for 7 years. I replaced my first one as i bought way to small. Even sold it and made profit.

The current one is probably 3 years old. key start and runs perfect. I replaced the spark plug this year R30 bucks. Oil i just use leftover oil from servicing the car. air filter is washable.

This thing is efficient. I get over a hour on a liter of fuel.

So with it connected to the db board the following will always be on

Outside lights 5 all led
cctv cameras
electric fence
alarm
3 ups
3 fridge / freezers
inside lights
tv
wifi

what i normally keep off but the generator can manage
Geyser. do have solar geyser so if overcast it will come on
Pool pump

MY wife still uses the kettle or microwave as needed.
I need one of these .. but at 0db please.. sigh
 
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