Understanding your electricity consumption chart

For many, it would be hard to ignore this chart in their electric bills as it would easily give them an idea on whether they have increasing or decreasing electricity consumption.

One of the common mistakes people do in interpreting this graph is comparing current energy consumption with the immediately preceding month. That is, when they see a column representing current consumption that is higher than the previous month, the immediate conclusion is that they have increased electricity consumption, and then vice versa.

This is right in a way but only partly, especially if you have air conditioners, electric fans, electric water heater, or any cooling or heating devices in your house. Your aircons or electric fans would be used more during hot seasons and less during cooler months. Ambient temperature could vary from month to month and thus, your electricity consumption too.

So how do you know whether you have saved or increased on your electricity consumption this recent month?

The chart above represents 13 months of monthly electricity consumption, not 12 as many would think. The above example starts from March 2009 to March 2010. In order to determine your comparative electricity consumption for the most recently billed month which is March 2010, you would be more technically correct if you compare it with March 2009. The underlying logic behind this is that the same months theoretically would have the same climatic conditions that affect your electricity consumption.

You would notice on the chart that March 2010 is slightly higher than February and significantly higher than December and January. However, look further backwards and you would see that March 2010 is about the same with that of March 2009. So in this example, I would say that the electricity consumption for the recently billed month is just about normal.

There... so I hope that after reading this, you will no longer get sad when getting high electric bills during summer and don't get too excited either when you see low electricity bills during the cooler months. On the other hand, it is possible that I only confused some of you since I myself got confused when I was writing this piece. You may post questions on the comments section below and I hope we can find the answer together.