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How does the kW power output of a split system air conditioning unit affect the energy efficiency?

Matt Mouritz · Director

When people look are researching split system Bonaire air conditioning in Perth, they can be confused by all the features and specifications detailed in the marketing literature. There are many different models to choose from, and one of the critical areas that most people are interested in is the energy efficiency of the unit. In this article, we will look at the relationship between the kW power output and the energy efficiency in a split system air conditioning unit.

The kilowatt (kW) output

Every Bonaire air conditioning system will have a stated power output in kilowatts (kW). This is often overlooked, but it’s extremely important, if you choose a split system air conditioning unit that’s too large or too small it will not be energy efficient. There are a number of factors to consider, such as the size of your home, the insulation levels, and the size or power output of your air conditioning system.

The capacity of a split system air conditioner is expressed in British Thermal Units or BTUs. The power output of the unit is measured in kW, and the energy efficiency is based on a start system here in Australia. Every appliance sold here has a score based on 1–5 stars, the more stars there are, the more energy efficient the appliance is. In any air conditioning system around 80 W of power is required per sq metre to cool or heat a space efficiently. Below we have listed general guidelines for some sample room sizes.

  • 20 m² – 2.8 kW
  • 30 m² – 4.2 kW
  • 40 m² – 5.6 kW
  • 50 m² – 7.0 kW
  • 60 m² – 8.4 kW

Some of the leading air conditioning system manufacturers such as Bonaire have split system air conditioners that have extra features to make them more energy efficient. This can include features that detect and adjust for sunlight levels in a room or intelligent systems that can learn and adapt to how you live. There are also energy efficient air conditioner systems available that go even farther.

Energy efficient air conditioning systems

The first thing that you need to know about these types of air conditioning systems is that they are more expensive up front. They cost more money because they are at the cutting edge of the HVAC industry and they have technology that has not trickled down to more affordable equipment at this time. However, if you can afford a unit like this, it will cost less to run, and the higher purchasing costs will be recouped over time.

If you want to know whether to purchase an energy efficient or a 5 star rated split system unit, it will be necessary to make the following six calculations.

  • Compare the purchasing prices.
  • Evaluate your daily energy usage.
  • Check the cooling power in kW.
  • Compare the energy that would be used over a set period in kW.
  • Extrapolate your figures over a ten year period to work out the running costs.
  • Compare the two split system units to find out the total cost of ownership.

When you take the time to compare two different air conditioning systems in this way, you can find out the system that offers the best value for money.

If you’re looking for Bonaire air conditioning in Perth contact us here at Mouritz for expert assistance.

Matt Mouritz · Director

Matt is a director at Mouritz, a Perth based air conditioning and solar specialist. He shares straightforward advice on choosing, running and looking after cooling, heating and solar systems, with a focus on what actually works for Perth homes and our local climate. When he is not writing, he is helping customers find the right setup for their home and budget.

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