I’ve finally gotten round to plotting our gas consumption on a graph. I’m not expecting a measurable drop in our consumption yet. We finished insulating our living room in July 2011 and I’m only just getting round to insulating our bedrooms (Feb 2012). We installed a new condensing gas boiler and solar thermal in July 2011. But we also had a baby in August 2011 so we’ve had the heating on far more than normal for the last quarter of 2011!

Temperature data from the Heathrow MetOffice weather station

What does this data tell us? And why did it take a fair amount of effort to plot our gas consumption?

The solar thermal system (installed July 2011) looks like it reduced 2011’s Q3 gas usage compared to previous years. In terms of heating, every quarter of 2011 had the lowest or second lowest gas consumption; but 2011 also had the warmest or second warmest q1 and q4 in the timespan. I am pleased that our gas consumption for q4 2011 is the second lowest in our record, despite that fact that we left heating running all night every night (to keep our bedroom at 18 degrees C for the baby) during q4 2011.

To produce these graphs, I had to interpolate our gas meter readings using Python. I’ll update this blog post with more details soon.