Air conditioning while running on home solar and batteries

Jan

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Best air conditioners for home solar systems

South African households who want their small to medium-sized solar systems to run air conditioners should use inverter-type systems.

The amount of power needed to regulate the temperature of a room can be substantial, particularly if the outdoor temperature is significantly lower or higher than your ideal indoor temperature.
 
Greatest thing I did last year, was changing all the office and home aircons to inverter type. I've seen consumption as low as 600w on the 12000 BTU units. Plus they are all on Wifi and you can turn them on before arriving in said room etc and can monitor if any staff has left theirs on via the app.

The solar system loves it too as it runs them so so easily.
 
I have 8 AC's in the house - all inverters, 6 9000 BTU, 2 24000 BTU

Initialy outlay is a b***ch. Almost R55k more than non-inverters.

But I can run all 8 on cool on only solar power and I have a smallish system of 12 panels. Those things are extremely light on power.

In Winter they do use more though. But still nothing to go completely off book.
 
Oh the irony.

I literally have the unit in the picture at the bottom but it's a 18,000 BTU.

The maximum it ever draws is 2,144 watts and in total uses about 3-5kWh a day.

While the inverter will be better and I wouldn't install a new one that isn't inverted, it makes no sense to rip out the perfectly good working one in favour of it.
 
I've actually seen PV compatible aircons (e.g. https://www.deyeinverter.com/product/solar-air-conditioner/hybrid-ac-dc-solar-air-conditioner.html ) that can connect to its own set of PV panels ... but no idea how good they are, availability, etc.

Really hoped this article would discuss that... :-/
You get similar dedicated panel system with water geyser.
Don't do it.
Not a good idea to split the PV to dedicated devices - 3 dedicated panels for Air-Con, 4 dedicated panels for geyser, 2 dedicated panels for TV.

Just add some extra panels to your existing PV system as this allows the energy to be used elsewhere when the air-con is not running.
 
You get similar dedicated panel system with water geyser.
Don't do it.
Not a good idea to split the PV to dedicated devices - 3 dedicated panels for Air-Con, 4 dedicated panels for geyser, 2 dedicated panels for TV.

Just add some extra panels to your existing PV system as this allows the energy to be used elsewhere when the air-con is not running.
It is a good solution for someone that does not have an existing PV system
 
I have 8 AC's in the house - all inverters, 6 9000 BTU, 2 24000 BTU

Initialy outlay is a b***ch. Almost R55k more than non-inverters.

But I can run all 8 on cool on only solar power and I have a smallish system of 12 panels. Those things are extremely light on power.

In Winter they do use more though. But still nothing to go completely off book.
Sounds like you live in Hotazel.

I've changed all except one over the years, it's the 15 year old 9000btu one that sounds like a tractor when running. It's my favorite, because it's in the room where the outlaw sleeps. It's so worth the extra power it uses to keep her awake all night.
 
Greatest thing I did last year, was changing all the office and home aircons to inverter type. I've seen consumption as low as 600w on the 12000 BTU units. Plus they are all on Wifi and you can turn them on before arriving in said room etc and can monitor if any staff has left theirs on via the app.

The solar system loves it too as it runs them so so easily.
My 36000 BTU unit uses under 800W when idling... and it's SO QUIET!
 
Oh the irony.

I literally have the unit in the picture at the bottom but it's a 18,000 BTU.

The maximum it ever draws is 2,144 watts and in total uses about 3-5kWh a day.

While the inverter will be better and I wouldn't install a new one that isn't inverted, it makes no sense to rip out the perfectly good working one in favour of it.
I'm going to replace the one in my bedroom with an inverter unit just for the noise factor. I'll still reuse the old one upstairs for one of the guest rooms.
 
Are you two aunties going to contribute or just sit there and whine?

Well, the biggest piece of nonsense is stating that non-inverters always stay on at full power even when they reach the target room temperature.

"If you want to run the aircon during the night, one hour will drain 3,500 watt-hours of capacity from your battery."

"Conventional air conditioners have motors that can only run at fixed speeds, so they will still be blasting away even when the temperature is right."
 
This article is a disgrace - obviously no research was done and salespeople gobbly-gook was used as evidence when compiling it.

A 12000 BTU machine may produce 3.5kw of cooling or heating power. But because of how a heat pump works, it only consumes about a 3rd of that in electricity. So 1.2kw roughly at peak. I've never seen mine draw more than that. And my non-inverter model also has sensors and stops blowing my wig off when the temperature reaches "just right". And you know what? It also stops drawing power at that point because the compressor switches off.

An inverter cannot "save" much electricity - it may be slightly more efficient because it runs at lower speeds, but the laws of physics are the laws of physics: to cool x volume of air requires x amount of kWh. The only difference is in how it is delivered - spurts vs continually.
 
I have 8 AC's in the house - all inverters, 6 9000 BTU, 2 24000 BTU

Initialy outlay is a b***ch. Almost R55k more than non-inverters.

But I can run all 8 on cool on only solar power and I have a smallish system of 12 panels. Those things are extremely light on power.

In Winter they do use more though. But still nothing to go completely off book.
Depends on how quickly you can get it to the set temperature in order for it to reduce the power draw.

If it never gets to room temperature, the compressor runs at full power, and there's no difference between inverter or non-inverter.

This is why insulation becomes important, in addition to having the correct size aircon for the room size...
 
This article is a disgrace - obviously no research was done and salespeople gobbly-gook was used as evidence when compiling it.

A 12000 BTU machine may produce 3.5kw of cooling or heating power. But because of how a heat pump works, it only consumes about a 3rd of that in electricity. So 1.2kw roughly at peak. I've never seen mine draw more than that. And my non-inverter model also has sensors and stops blowing my wig off when the temperature reaches "just right". And you know what? It also stops drawing power at that point because the compressor switches off.

An inverter cannot "save" much electricity - it may be slightly more efficient because it runs at lower speeds, but the laws of physics are the laws of physics: to cool x volume of air requires x amount of kWh. The only difference is in how it is delivered - spurts vs continually.
Yeah the article references output power. Input power is what it would draw from source...
 
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