My house uses natural gas for space heat and domestic hot water. When analyzing the benefit of my solar collectors, the obvious thing to do is to examine the actual change in my gas consumption. To answer this, I've plotted the amount of gas I burned per heating degree day (HDD) per month. Using HDDs adjusts for the variability of the weather and allows an apples-to-apples comparison between different years.

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I thought I'd share some graphs showing the output of my solar collectors and the results of my recent renovations (collector installation included) on my home energy use.  Here is the heat collected (measured in kwh) plotted with the maximum daytime temperature:  read more... »

Today (Saturday November 20th) was the first sunny day in a while.  While cleaning up the breakfast dishes I was not surprised to hear the solar pump start.  When I checked I found that my solar tank was down to 20 degrees C, the solar collectors were at 29 degrees C and the outside temperature was minus 17 degrees C.  What did surprise me was that when I left the house to run some errands (around 10:40 AM) I found the collectors were still partially covered in snow! 

Snow covered collectors

This mean that my collectors managed to get a 45 degree C differential to the ambient temperature even while partially obscured.  How great is that?

 This just in from resident Net Zero House expert and Edmonton green leader Bob Heath:

The latest issue of Home Power magazine has an article entitled "Blast From The Past" written by Martin Holladay. He tested a 33 watt PV module that he had bought in 1980 for $275.00 US. He found that the module was still performing at better than factory spec. A quote from the article - "A PV cell is a rock that makes electricity."
Another quote from the same issue of HP - "A PV module is the closest thing we have to perpetual motion [and] is the most reliable electric generator in the known universe." —Joel Davidson, SOLutions in Solar Electricity

Germany will install 6,000,000 kilowatts of PV modules this year. Shouldn’t we Albertans also be investing in these en masse in order to make our electricity supply more resilient (not to mention greener) in a future of declining fossil fuel availability?