Generator or Inverter for residential use?

thechamp

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Thanks but thought I cant run geysers (have 3) from inverter???

Initially will have only 1 x 5KV. Will install 2nd 5KV next year.

Hopefully add more batteries as well. A frirnd had an outage for 4 days!
You can run anything that does not exceed the power rating of the inverter, the problem is usually the batteries and the continuous current they can supply while you are running the geyser, at 3000W you will need to draw about 62A from the 48V battery, unless you have a proper, massive battery bank you are going to fall short.

That is mostly why many installers prefer not to entertain the idea of feeding the geyser from the inverter.
 

adielk

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You can run anything that does not exceed the power rating of the inverter, the problem is usually the batteries and the continuous current they can supply while you are running the geyser, at 3000W you will need to draw about 62A from the 48V battery, unless you have a proper, massive battery bank you are going to fall short.

That is mostly why many installers prefer not to entertain the idea of feeding the geyser from the inverter.
At best my bank will be 4 pylotech lithium batteries.


For now only 2 lithium batteries
 

thechamp

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At best my bank will be 4 pylotech lithium batteries.


For now only 2 lithium batteries
Then you can technically run a Geyser from a 5kVA inverter connected to those, it just becomes complicated when you have a permanent load like a geyser, you'll forget about it and switch on other stuff which will cause the inverter to trip. A good management system could probably sort this out where you run the geyser at night while nothing else is drawing power.
 

Speedster

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Then you can technically run a Geyser from a 5kVA inverter connected to those, it just becomes complicated when you have a permanent load like a geyser, you'll forget about it and switch on other stuff which will cause the inverter to trip. A good management system could probably sort this out where you run the geyser at night while nothing else is drawing power.
Or afternoon when batteries are fully charged.
 

Speedster

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Just to expand on the solar geyser thing. You need about 6kWh per day to heat a 150l geyser (obviously depending on the amount of water usage). Retrofitting a 150l geyser for solar is about R15 000. If you have the inverter already, adding 6kWh of PV is about 1kW of extra panels (assuming there is no existing excess capacity), which will be about R7 000. If you have excess PV capacity in your system you'll need to add even less.
 

adielk

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Just to expand on the solar geyser thing. You need about 6kWh per day to heat a 150l geyser (obviously depending on the amount of water usage). Retrofitting a 150l geyser for solar is about R15 000. If you have the inverter already, adding 6kWh of PV is about 1kW of extra panels (assuming there is no existing excess capacity), which will be about R7 000. If you have excess PV capacity in your system you'll need to add even less.
I have 3 (three) geysers and a 5KV inverter plus 2 x 3.5kw x 48v pylontech lithium batteries.

No PV panels. Willing to add PV panels instead of retrofitting but would require more batteries and def another inverter?

6kwh x 3 = 18kwh daily.
 

Speedster

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I have 3 (three) geysers and a 5KV inverter plus 2 x 3.5kw x 48v pylontech lithium batteries.

No PV panels. Willing to add PV panels instead of retrofitting but would require more batteries and def another inverter?

6kwh x 3 = 18kwh daily.
My point is you don't need any batteries for the geyser, only PV. The inverter may well be too small for 3 geysers though, unless you can find a way to stagger their charge times.

This is all assuming you have Eskom backup for cloudy days
 

Vuilhaas

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I have 3 (three) geysers and a 5KV inverter plus 2 x 3.5kw x 48v pylontech lithium batteries.

No PV panels. Willing to add PV panels instead of retrofitting but would require more batteries and def another inverter?

6kwh x 3 = 18kwh daily.
Converting a geyser to solar (a thermosiphon system) is cheaper than buying a new Pylontech battery and will significantly lower your daily power consumption. I would definitely go that route if I were you
 

Speedster

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Converting a geyser to solar (a thermosiphon system) is cheaper than buying a new Pylontech battery and will significantly lower your daily power consumption. I would definitely go that route if I were you
Why do you need an extra battery for a geyser?
 

Speedster

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You don't, I was just pointing out that the solar conversion is cheaper than a battery
Which is a pointless point to point out, in the same way that pointing out a Big Mac is cheaper than a new TV.

Putting up a solar geyser (or retrofitting an existing geyser) is pricier than modifying a PV setup to accommodate the geyser.
 

chrisc

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I have read through pages of comments, and have one question please:

My neighbour in Montagu wants to buy a 1kW (or thereabouts) inverter and battery (or batteries) to keep his TV and media player going for a few hours

The inverter should also charge the battery

What particular model should he be looking at?

Thank you
 

Speedster

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I have read through pages of comments, and have one question please:

My neighbour in Montagu wants to buy a 1kW (or thereabouts) inverter and battery (or batteries) to keep his TV and media player going for a few hours

The inverter should also charge the battery

What particular model should he be looking at?

Thank you
Mecer or Ellies trolley

 

Vuilhaas

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Which is a pointless point to point out, in the same way that pointing out a Big Mac is cheaper than a new TV.

Putting up a solar geyser (or retrofitting an existing geyser) is pricier than modifying a PV setup to accommodate the geyser.
How is it cheaper? If your geyser is a 3kw unit, then wouldn't you need 10 300w PV panels (at around R2k each) just to accommodate the power requirements of one geyser? A thermosiphon conversion is around R12k for a 150l geyser.

The thermosiphon option also only takes up a small portion of your roof area instead of covering your entire roof with panels just for your geyser.
 

Sinbad

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How is it cheaper? If your geyser is a 3kw unit, then wouldn't you need 10 300w PV panels (at around R2k each) just to accommodate the power requirements of one geyser? A thermosiphon conversion is around R12k for a 150l geyser.

The thermosiphon option also only takes up a small portion of your roof area instead of covering your entire roof with panels just for your geyser.
PV to heat for water is stupidly inefficient and expensive.
Rather use a proper solar geyser.
 

Speedster

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How is it cheaper? If your geyser is a 3kw unit, then wouldn't you need 10 300w PV panels (at around R2k each) just to accommodate the power requirements of one geyser? A thermosiphon conversion is around R12k for a 150l geyser.

The thermosiphon option also only takes up a small portion of your roof area instead of covering your entire roof with panels just for your geyser.
I disagree. See this post

 

Speedster

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PV to heat for water is stupidly inefficient and expensive.
Rather use a proper solar geyser.
If you're only heating water, by all means. If you have the PV already, modifying for water heating is the easier / cheaper option
 
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