How green is my household?: Spring 2007 power bill

January 11, 2008

Spring 2007 power bill

Hi, Bruce here, I've been comparing our power bills for spring 2007 and 2006, and found that in both years, our electricity use dropped by 15%, as did our bill. So, we're continuing the decline in household energy use. However, it isn't quite a fair comparison, because we didn't start our first carbon neutral year until part way through spring 2006. By last summer we were working hard to reduce our energy use, so it will be interesting to see if we can make further reductions this summer. I suspect we might, but only by a few percentage points, certainly not by another 15%.

As the spring bill is the last for the calendar year, I've now got all the figures for 2007, so have created a graph comparing our annual electricity use and cost for the past five years:

Click on image to enlarge

You can clearly see the effect of installing a solar hot water system in April 2004. Overall, we reduced our electricity use by 60% between 2003 and 2007, with daily use going from 25.7 kWh in 2003 to 10.8 in 2007.

The costs are harder to analyse because, since 2005, we've paid a premium to be on 100% green power; also, electricity prices have risen. Despite this, our annual bill has dropped by more than 30%, saving us about $400.

Climate scientists have warned that the world needs to reduce greenhouse gas emissions by at least 60% of 1990 levels by 2050. As far as stationary energy use is concerned, one house has already achieved that goal, and it only took 5 years, not 60!

Posted at 02:27 PM in Electricity | Permalink