Air conditioners are a household appliance that usually consumes the most energy, accounting for about 40% of electricity bills. Keeping a home comfortable and keeping bills down is possible when you choose an energy efficient air conditioner. In our article, we explain what energy efficient air conditioners are, the types of energy efficient air conditioners, and how to choose an energy efficient air conditioner.

What is an Energy Efficient Air Conditioner?

An energy efficient air conditioner is a unit that heats or cools a home with less energy consumption. Energy efficient air conditioners cost less to run and have less impact on the environment. The energy efficiency of an air conditioner is determined by energy efficiency ratio (EER) which is the ratio of the cooling capacity to the power output. An energy efficient air conditioner will have a higher EER than a less energy efficient unit.

How to Tell if An Air Conditioner is Energy Efficient

There are a number of ways to identify if an air conditioner is energy efficient. These include:

• Energy Rating Label: The best way to identify if an air conditioner is energy efficient is by looking at the energy rating label. This is a label on products that provides a star rating and energy consumption information. The star rating is a measurement of how much energy a product uses compared to other products. The more stars, the higher the energy efficiency compared to other similar sized units. Most air conditioners have been 1 and 6 stars but, with energy efficiency improving all the time, there are some products with 10 stars. The energy consumption figure is the amount of electricity a product uses each year in kilowatt hours (kWh). Energy consumption can be compared to any unit, regardless of the features or size. If you want to estimate how much the air conditioner will cost to run per year, multiply the energy consumption figure on the rating label by the amount you pay for electricity per kWh. For example, an air conditioner with an energy consumption figure of 384 multiplied by energy cost of 25c per kWh that runs for approximately three hours a day will cost an estimate of $288 per year.
• Energy Efficiency Ratio/Seasonal Energy Efficiency Ratio: The EER and SEER measure how an appliance uses energy. EER is the ratio of output cooling energy to input electrical energy at peak time like the height of summer. SEER is the ratio of output cooling to electrical energy consumption on average, including the highs and lows of a home’s cooling patterns.
• Inverter Technology: An air conditioner with inverter technology is likely to be about 30% more energy efficient than one without an inverter. Because it keeps compressor speed to a minimum it reduces energy consumption.

Types of Energy Efficient Air Conditioners

There are different types of energy efficient air conditioners. By understanding the options on the market, their features, pros and cons, you can make an informed choice on the right one for you.

• Split system. The most common types of air conditioners in Australia, split systems have an indoor and outdoor unit connected by pipes and wiring. Traditional split systems cool one room at a time, up to 60m2. These are quiet units as the noisiest part of a split system is outside the home. Split system air conditioners are known to be one of the most energy efficient appliances for cooling.
• Evaporative cooling. Evaporative coolers are an energy efficient and natural type of cooling, removing the heat from the air in a home. Evaporative coolers can reduce temperature by 10 degrees. They are a more natural approach to air conditioning in that they don’t use any chemical refrigerants. This type of air conditioning works by blowing air over water on a filter or sponge. Outside air is drawn through the unit and cooled via this evaporation process.
• Ducted air conditioning. Ducted air conditioning involves a central unit that is connected to ducts via pipes that distribute cool air throughout the home. This type of unit provides powerful cooling throughout a home. Because it is a larger unit, they may not be as energy efficient as other types of cooling. However, a unit with inverter technology will use much less energy.
• Wall units. This is a single box unit installed through an external wall or window. Wall units can cool open plan areas of up to 50m2. Modern wall units are equipped with an auto-swing, programmable timer functions and remote controls that provide higher energy efficiency.

The Most Energy Efficient Air Conditioners

The most energy efficient air conditioner overall is a split system. The design with an indoor and outdoor unit results in split systems using less energy to cool a room than other types of air conditioners. We have compiled a list of the most energy efficient air conditioners in the categories of split system, evaporative cooling, ducted and wall air conditioning.

Most energy efficient split system

Daikin Cora 2.5kW

This is the highest efficiency split system air conditioner, known for its quiet and reliable performance. The Daikin Cora 2.5kW has a 6 star energy efficiency rating and an EER/COP of 5.10/5.00. It uses R32 refrigerant which provides 66% lower ‘global warming potential factor’ than other split system air conditioners. The Daikin 2.5kW uses inverter technology to enhance energy efficiency, boasting the 2-area intelligent eye feature to save energy and minimise draught by moving the airflow towards or away from everyone in the room. The Daikin Cora 2.5kW is known for its whisper-quiet cooling operation with ‘industry-leading’ efficiency levels. With a dBA of just 19dBA, it is also barely audible to most ears.

Most energy efficient evaporative cooling

Breezair Extraordinaire

This is one of the best evaporative coolers for energy efficiency, with a cooling capacity of 17.4kW. It is the winner of the Good Design Award 2020 and the Energy Efficient Product of the Year 2019. It has an aeronautically engineered fan to maximise energy efficiency and air flow, while keeping the noise to a minimum. The fan pulls hot air into the unit and transfers it across the water, which then evaporates into vapour and is distributed as cool air into the room. This is the best evaporative cooler for energy efficiency as it has up to 80% less CO2 emissions than ducted reverse cycle air conditioning.
*Evaporative coolers are not subject to any energy efficiency rating requirements so EER and star rating is not available.

Most energy efficient ducted cooling

Daikin Premium Inverter Ducted Cooling

The Daikin Premium Inverter Ducted Cooling system is one of the most energy efficient systems in the category as it offers remarkable energy efficiency compared to some counterparts. It has a 5 star rating and an EER/COP of 3.30/3.87. This unit has a flexible design and can be retrofitted with existing systems. It has quiet night mode, and has heating and cooling capabilities. These systems are available in sizes ranging from 7.1kW to 24kW capacity.

Most energy efficient wall air conditioner

Kelvinator window-wall air conditioners

These window and wall air conditioners all have a 2 star energy rating which is good for a window/wall air conditioner as they don’t tend to be as energy efficient as other forms of cooling. Kelvinator window/wall air conditioners range in size from 1.6kW to 6kW. Window or wall air conditioners are one of the more budget friendly types of cooling to install. You can purchase a 1.6kW wall unit from Kelvinator for as little as $629 which is impressive for a unit that provides good comparative energy efficiency.

How To Choose The Most Energy Efficient Air Conditioner

Energy efficiency is gauged by the amount of electricity it takes to provide cooling to a home. However, the most energy efficient air conditioner for you will depend on a number of factors specific to your home and individual needs. We take a look at everything to consider here to find the most energy efficient air conditioner.

• Suits the space: When choosing the right sized air conditioner, you need to make sure it suits the space and take into account the room size and layout of your home. It can be tempting to want to buy the biggest air conditioner without looking at the space it needs to cool. A unit that is too large may make the room too cold, and use unnecessary energy. Alternatively, you might want to save money by installing a small unit which may not be able to provide sufficient cooling. In this case, it may need to be run on maximum at all times, causing wear and tear, and higher energy bills. When choosing the right size or capacity, remember it is measured in kilowatts. A small unit that has a 2.2kW capacity is suited to a bedroom, while a 6kW unit will keep a large open plan living room cool.
• The climate: Consider the climate when looking into which type of air conditioner to buy. Climate has an impact on how efficient an air conditioner will be. Dry climates are ideal for split system or evaporative coolers, while humid climates require a refrigerated system to provide maximum cooling.
• Energy efficiency ratings: Most air conditioners will display an energy efficiency rating. This is a label with stars that show how efficient the system is compared to other systems of the same size. The more stars, the better the energy efficiency.
• Controls: An air conditioner with controls like a thermostat and timer will be more energy efficient. The thermostat and timer helps to control the room temperature for maximum savings. The timer allows you to control when the air conditioner is on and will not let it run indefinitely and use unnecessary electricity.
• Smart features: Smart air conditioners can help reduce energy consumption as they have features like remote access to turn the unit on and off, versatile temperature settings, integration with other smart home devices, energy save functions and wifi connectivity.

How To Run An Air Conditioner Most Efficiently

Once you have your energy efficient air conditioner, there are some ways to ensure you get the most out of it. Here are some ways to ensure an air conditioner operates most efficiently.

• Adjust temperature settings: Set the temperature as high as possible while still being comfortable. By having the thermostat set at a couple of degrees higher, you can save hundreds of dollars on energy bills. A degree or two warmer will reduce running costs by about 10%.
• Don’t leave the air conditioner running: There is a train of thought that leaving an air conditioner running all day will help save on energy bills but it is not recommended unless you are away for a small amount of time. If you are away from the home for a significant amount of time, always turn the air conditioner off as it wastes unnecessary energy cooling a room or home with no one in it.
• Consider fans: Use a portable or pedestal fan to circulate the cool air that is produced by the air conditioner.
• Insulate the home: A well insulated home will keep the cool air in for a longer period of time. This means not only wall insulation but consider double glazing on windows for extra energy efficiency.
• Regular maintenance: Make sure you have the unit regularly serviced and maintained so it will work as efficiently as possible.

Making sure your home is cool in summer is important but you also want to save on electricity costs. That is where energy efficient air conditioners come in. Our article guides you through the best energy efficient air conditioners, and how to choose the right air conditioner for your home. For further details, contact the experts in air conditioning at Simplyair.