[speedgibson] Speed Gibson: Cold Reality

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Posted by Speed Gibson:
Cold Reality
http://speedgibson.powerblogs.com/posts/1199744361.shtml


   I had an hour to kill, so I put together a spreadsheet with sunrise
   and sunset times by month, plus the average high/low and record
   high/low temperatures. I then calculated the usage of a light bulb
   that switches on at sunset, off at sunrise. This computed to about
   4,300 hours. This would cost about $43 a year to light a 100 watt bulb
   at 10 cents a kilowatt hour.
   A CFC bulb is about 4 times as efficient as a TAE (incandescent) bulb,
   so it will cost about $12, saving you $31 a year, just for that one
   bulb. Or would it?
   Suppose it was an indoor bulb as most are, say a hallway you want
   illuminated all night for the kids' peace of mind. Is all that heat
   wasted? Not if it's below 70 degrees outside, i.e., the furnace could
   be running anyway. What my crude spreadsheet tells me is that occurs
   at least 80% of the time. Don't forget, the average low temperature is
   64 degrees in July.
   It wouild be fair to knock that down a bit for peak summer days given
   that the home's residual heat would swamp such effects, but the bulb
   also runs far fewer hours per day. Even so, the TAE bulb does not
   waste significant energy overall for fall, winter, and spring.
   Granted, your (non-electric) furnace is likely more efficient at
   producing heat. But the greenies seem not to worry about such things
   when urging us to plug in an electric car at night, and this varies
   significantly on a house by house basis.
   The optimum solution is obviously to put in a TAE bulb during the
   heating season and use the CFC bulb in the summer. But the hell with
   that. If you feel better putting in CFC's everywhere, fine. I have
   about 10 CFC's myself, but I'll decide when and where.