Heat pumps are a great way of reducing the energy consumption of a household, and thus reducing the electricity costs. Besides their obvious benefits, they became more and more popular in the past years, as people are more and more aware of the fossil fuels emissions ‘impact on our planet.
Now, if you have already bought a heat pump, and are wondering if it is cheaper to run it throughout the day, instead of turning it OFF before you leave for work, and turning it back ON when you come back, the answer is NO, it is not cheaper, in fact it will cost you more. But of course, there is always a but, so you need to keep reading to better understand why it is like that.
One of the main parameters that influences the performance of a heat pump is the outdoor, or environment temperature. The lower the temperature outside, (during the winter, for example), the more work you need to put to heat up your house. Surprisingly, most of the heat pumps have the highest COP (Coefficient of Performance) at much lower temperature that you would expect- but more about that later, in another post. You will need to answer for yourself the next two questions before deciding what is best for you.
HOW WELL IS YOUR HOUSE INSULATED?
Now, if your house is not well insulated, then it means you are losing heat every second. The heat that you lose to the ambient due to bad insulation, or not air-tight windows, it’s called “heat loss”. It is this heat loss, that you need to calculate, or take into consideration, when you decide if it will be cheaper to leave the heat pump ON all day or not. Do you have a well-insulated house? Then the heat loss is at its minimum, and it might not be such a bit difference in electricity consumption if you were to run it all day long.
WHAT IS THE OUTDOOR AMBIENT TEMPERATURE?
Is the temperature outside -25℃ or more like 0℃ during the winter days? The higher the ambient temperature, the lower the temperature difference between outdoors and indoors. A lower temperature difference means a lower heat loss, but also less work for your heat pump. This translates to lower electricity costs for you.
WHAT SHOULD YOU DO?
If you are in for cutting your electricity bills at all costs, then the obvious answer is to turn OFF your heat pump when you leave for work. However, we all know that is not nice to come back to a cold house, so probably the idea of keeping the heat pump ON is very appealing. If you have the opportunity, the time, and the money, you should invest in proper insulating your house first. Then, you can always leave your heat pump ON at a lower temperature while you are away. For example, if you like to keep 22℃ while you are at home, then you can have the heat pump run on a lower temperature, like 15℃ while you are away. In this way, you will come back to a not-that-warm home, but warm enough that you will feel welcomed. Then, you can increase the output temperature of your heat pump to 22℃, and since the indoor temperature is already at 15℃, it will not take that long to reach your desired temperature conditions.