In this blog I will discuss about measuring the past performance of our Electricity usage. As I mentioned in the previous blogs we set a goal of reducing our household power consumption by 30%. We did not have any basis at that time since we did not have any measurements. I collected the previous electricity bills and the raw data is presented in table below:
The first thing we need to is remove the data that is not relevant to our current analysis. For example, we do not need 2006 and early 2007 data as they represent the consumption of our previous home – which was a smaller unit. Removing the unwanted data results in the following table:
There were few surprises to me when I look at the table:
July, October 2007 and 2008 were extremely close. We had a very consistent usage pattern. However, in 2009 the usage has decreased substantially. In fact in 2009 we have used less electricity throughout the year.
I can explain them some of the decrease in the usage. It is because of our vacation trips that reduced the consumption. Especially in December we went for few weeks of overseas trip. However, I am not clear at this stage the reasons behind the fall in usage. This needs further analysis.
Considering these facts, we can consider July and October data for the purpose of “baseline”. This baseline is a reference point for the goal we defined.
July baseline based on 3 year average is: $442
October baseline based on 3 year average is: $710
If I take 30% reduction of this figures, I get the number similar to 2009 consumption. The target (goal) is to spend $310 and $497 which are comparable with 2009 data. In other words we are not reducing the electricity consumption compared to 2009.
Instead, if I take only 2009 data as the baseline, my target should be $212 and $333.
Frankly, I do not know why our power consumption was less in 2009. If I can sustain that level of consumption I will be happy. My decision is to take the 3 year average as the baseline. In the coming weeks, we will do some analysis of the reasons behind our reduced consumption last year.
We also borrowed a kit from our Council library to monitor power consumption. I will share my experience in the future blogs. Stay tuned.