Tracked my residential energy usage for the past 15 years

Lived in the same house for the past 15 years. I've plotted my natural gas and electrical usage in graph form every month for those past 15 years.

Natural gas I plot therms/day. Electric I plot kwh/day. Both are based on how many therms or kwh used per billing period. The billing period is spelled out in days as '29 days' or '32 days' for example.

During that 15 years I've slowly made multiple improvements in energy efficiency. The house was built in the 60's. When we arrived the roof and walls were not insulated. Incandescents everywhere. Old AC unit. Windows were single pane with old style storm windows and were not low E. Slowly over those 15 years we have:

Replaced all the windows with low E double pane.
Heavily insulated the attic

Sealed all cracks and holes in walls
Replaced the AC unit with a much more efficient unit
Replaced the old washing machine with an energy star unit
Use flourescents instead of incandescents
Programmable thermostat added

A year ago we insulated the exterior walls with blow in insulation. 30 large bags of cellulose insulation blown in between every joist in every wall.

Generally speaking the usage per year is basically unchanged when I average out the yearly usage. There are a few spikes where there was a rough summer or winter, which is understandable. But, all in all, no decrease in usage.
Electric usage spikes during end of Summer and is at its lowest in mid winter. Opposite for gas usage obviously. 15 'humps' on my graph.

Granted we have added two kids who are now pre-teens now. However, by far our largest energy usage is AC in summer and heating in winter, which aren't driven by extra people using more energy. The AC and heating are what cause the extreme spikes in summer and winter.

Whats up with that? And, no, I don't have a smart meter yet.

Last Edited by FLUFFY PUPPY on 07/21/2009 01:48 AM