I sure am glad I read other people's blogs - it's keeping me on my toes! And a lesson in humility is never a bad thing.
I was visiting over at Learning to Step Lightly yesterday and in perusing her natural gas usage numbers I noticed a large error in my own calculations. I've been mistakenly touting our household as having achieved a 90% reduction in our natural gas usage, for both 2006 and 2007. I was proud of this, proud about how frugal we were in our house, even before jointing the Riot For Austerity. In fact, just the other day I turned the gas fireplace on because I was a bit chilly and thought I could comfort myself with both the warmth from the fire and the knowledge there was some 'slack' in our numbers. So what the heck eh? Turn on the fireplace.
Well, it turns out I made a miscalculation when I was converting Therms to gigaJoules, and put the decimal point in the wrong place. I thought the average North American household used 106 gJ of natural gas per month, but it turns out the average is only 10.6 gJs per month! Our 2007 average of 9.29 gJs/month is under this, but just barely! So instead of thinking we were only using 8.8% of the North American monthly average, we were in actuality using 88% of it. Time for some re-assessment here. I'll have to cloak myself in a sweater rather than in smug self-righteousness.
I'm fairly certain the rest of the numbers are I've posted in the past are correct, but if anyone notices any strange anomalies (past or future), please let me know!
2 days ago