One of the questions our customers ask most often is “how much does ducted air conditioning cost to run?” Sometimes this is asked after the exact air conditioning components have been selected, when it is relatively easy to calculate running costs. Other times a customer will ask without knowing the make, model, size, and other specifics of their air conditioning needs. That’s a little like asking what it costs to run a new Toyota car: without knowing the size of engine, the driving conditions, and the cost of fuel there is no way to accurately assess running costs.
How to calculate ducted air conditioning running costs
The first thing to do when calculating the cost of running air conditioning is to select your air conditioning units. You’ll need to consider the space you need cooled (or heated) and then size your unit requirements from this. You should also consider the energy rating of different units: the higher the rating, the more energy efficient the unit is. With your units selected, you can now do some simple calculations to accurately estimate the running costs. Here’s how:
Step 1: From a recent electricity bill find the cost per kWh in cents.
Step 2: From the air conditioning manufacturer’s brochure, or the printed label on the side of your unit, find the electrical consumption (Total Input, kw) at its rated capacity.
Step 3: Multiply the cost per kWh by the unit’s electrical consumption at its full rated capacity.
Step 4: The answer is the cost per hour in cents.
Step 5: Calculate your daily cost to run ducted air conditioning by figuring out how long it will run and at what capacity. For example, if your electricity costs 20 cents per kWh and your unit has a Total Input of 3kw per KWh at full rated capacity, the cost per hour would be 60 cents p/h. If you intend to run the unit for 8 hours at 50% capacity, then the cost per hour would be:
20 x (3 x 50%) = 20 x 1.5 = 30 cents p/h
And the cost for 8 hours would be 30 x 8 = $2.40.
And that’s all there is to it! Don’t forget, though, that you might have different rates charged for your electricity at different times of the day. If this is the case, you will need to make more than one calculation.
When your ducted air conditioning is up and running, it will benefit from regular servicing to keep it in tip top condition – and so will your running costs.