Skip to content
View in the app

A better way to browse. Learn more.

Power Forum - Renewable Energy Discussion

A full-screen app on your home screen with push notifications, badges and more.

To install this app on iOS and iPadOS
  1. Tap the Share icon in Safari
  2. Scroll the menu and tap Add to Home Screen.
  3. Tap Add in the top-right corner.
To install this app on Android
  1. Tap the 3-dot menu (⋮) in the top-right corner of the browser.
  2. Tap Add to Home screen or Install app.
  3. Confirm by tapping Install.

Large Aircon vs Multi Zone Aircon - Which is Better on Solar?

Featured Replies

Hi

We want to plan the aircons and the solar together. We live in a hot climate near Kruger. It's nearly 30 deg and sunny on most winter days, summer is hotter.

House Layout

So we have a house layout that looks like the attached image.

  • Small Squares 16m2
  • Large Left Squares 36m2
  • Main Rectangle: 65m2 (lots of glass as well)

Aircon Usage Times

  • Bedrooms we'd run at night. (smaller squares on right and larger squares on left)
  • Living Area - only run during the day (large rectangle in middle)

A Few Quick Questions

  1. Would you recommend 1 aircon per room?
  2. Or would you recommend a multi zone system? https://acdirect.co.za/product-category/air-conditioner-multi-split/three-zone/

What is the best setup for solar? 

Home Layout.jpg

Have you looked at indirect evaporative cooling?   They don’t add humidity, use low amount of energy and you could do a unit that has its splitter in roof space and octopus legs to pump fresh cooler air via bedroom ceilings.     If I could redo my house I would go that route as I really hate sleeping with aircon and evaporative air is new fresh clean cooler air.

  • Author
5 minutes ago, macafrican said:

Have you looked at indirect evaporative cooling?   They don’t add humidity, use low amount of energy and you could do a unit that has its splitter in roof space and octopus legs to pump fresh cooler air via bedroom ceilings.     If I could redo my house I would go that route as I really hate sleeping with aircon and evaporative air is new fresh clean cooler air.

Thanks! Do you have any links to any energy efficient ones to consider?

1 hour ago, AlexanderR said:

Hi

We want to plan the aircons and the solar together. We live in a hot climate near Kruger. It's nearly 30 deg and sunny on most winter days, summer is hotter.

House Layout

So we have a house layout that looks like the attached image.

  • Small Squares 16m2
  • Large Left Squares 36m2
  • Main Rectangle: 65m2 (lots of glass as well)

Aircon Usage Times

  • Bedrooms we'd run at night. (smaller squares on right and larger squares on left)
  • Living Area - only run during the day (large rectangle in middle)

A Few Quick Questions

  1. Would you recommend 1 aircon per room?
  2. Or would you recommend a multi zone system? https://acdirect.co.za/product-category/air-conditioner-multi-split/three-zone/

What is the best setup for solar? 

Home Layout.jpg

I would go with single room mini split, last time I checked it was the cheaper option and you can run shorter pipe lengths between inside and outside units giving better efficiency. I have both the Samsung inverter and LG Dual Inverters mini splits, I much prefer the LG Dual inverter one, it also has a mode where it limits the power it consumes, useful if running off batteries or you are getting close to your inverter limits. The LG ones are not always available however. 
 

One more thing, if you stay at 18000 BTU or less, you can plug the unit into a wall socket, so no dedicated electrical line to DB required, that makes the installation cheaper as well.

Strong like bull:
https://acdirect.co.za/product/lg-dual-inverter-wall-split-9000-btu-hr-inverter-air-conditioner/

Edited by HendrikBigChief

When considering solar power efficiency, multi-zone air conditioning systems generally have the edge over large single-unit systems. Multi-zone setups allow for more precise temperature control, letting you cool only the areas that need it, thus reducing overall energy consumption. This efficiency aligns well with solar power, maximizing the utilization of renewable energy.

On 2024/05/27 at 9:56 AM, AlexanderR said:

Thanks! Do you have any links to any energy efficient ones to consider?

Mine are factory-size but try Breezair, pretty sure they have a residential size indirect evaporative cooling system

  • 2 weeks later...
  • 1 month later...
  • 3 weeks later...

 

 

On 2024/05/27 at 8:49 AM, AlexanderR said:

Hi

We want to plan the aircons and the solar together. We live in a hot climate near Kruger. It's nearly 30 deg and sunny on most winter days, summer is hotter.

House Layout

So we have a house layout that looks like the attached image.

  • Small Squares 16m2
  • Large Left Squares 36m2
  • Main Rectangle: 65m2 (lots of glass as well)

Aircon Usage Times

  • Bedrooms we'd run at night. (smaller squares on right and larger squares on left)
  • Living Area - only run during the day (large rectangle in middle)

A Few Quick Questions

  1. Would you recommend 1 aircon per room?
  2. Or would you recommend a multi zone system? https://acdirect.co.za/product-category/air-conditioner-multi-split/three-zone/

What is the best setup for solar? 

Home Layout.jpg

 

Whether to use a number of smaller air conditioners or one larger multi-zone system is a matter of a personal preference. Multi-zone system will be cheaper and a bit more energy efficient, but there would be no redundancy. Once the outdoor unit fails you're done. On the other hand, shared outdoor unit will take much less space.

A number of discrete air conditioners will bring redundancy but I can't imagine a house with let's say 4 outdoor units mounted on.

In my country, most of the home aircons are single-phase, which is ideal for a small solar. Commercial units are 3-phase, which might be a problem sometimes. Just double-check before placing an order.

 

To the picture of a proposed setup: This will not work good. Cold air from the unit travels really slow and is unable to pass thru the walls and doors. Even if the doors would be open 24x7, the first kids bedroom will be cold, while the 2nd and 3rd will be much hotter. For the efficient cooling you need to install a dedicated indoor unit in the every room (or take down all the inside walls).

I know about houses where the indoor unit is mounted in the hallway that runs across the whole house, with the bedroom to the right and left from it. It works somehow, but in order to have a decent temperature in the bedrooms the hallway has to be kept freezing....which is not comfortable at all.

 

 

 

 

Let me share some numbers, as this might help with the solar setup planning:

  • This is 24 000 BTU/h minisplit unit
  • Cooling cca 50m2 livingroom+kitchen
  • Target temperature 22°C
  • Outside temperature is 35°C during day and 23°C over night

Power draw chart, 24hrs duration:image.thumb.png.fa2bed2a774af80119bc071b8b20480f.png

Energy consumption over 30 days:image.thumb.png.b9068f6b3d228baf6048df6827516d55.png

  • So it's roughly 6kWh of energy per day for cooling.
  • Normal power draw is 200 to 1000W, with occasional spikes up to 2000W.
  • Looking at the chart, it would be better to stop the aircon during the night, as it's not really needed and there are too many starts/stops of the compressor which is not good for the longevity of the unit.

Hope this helps ;)
Youda

PS: As monthly average might be tricky and misleading, here's the daily consumption chart for the last 30 days:averageistricky.thumb.png.017edf85e4f6ca32dd814672bfc0a093.png

 

Edited by Youda
more charts

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

Account

Navigation

Search

Search

Configure browser push notifications

Chrome (Android)
  1. Tap the lock icon next to the address bar.
  2. Tap Permissions → Notifications.
  3. Adjust your preference.
Chrome (Desktop)
  1. Click the padlock icon in the address bar.
  2. Select Site settings.
  3. Find Notifications and adjust your preference.