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Fuquay Varina, North Carolina, United States
A guy finding out if life really does begin at 50.

Tuesday, August 14, 2012

Never Assume

My refrigerator is 30 years old this month. It's a Kenmore that I got when I bought my first house all those years ago. It's served me well. In the 30 years I've replaced the thermostat, the fan motor, and the ice maker (twice). The ice maker started messing up 5 years ago and I decided not to fix the ice maker a third time. I've been thinking about replacing the fridge ever since. I remember why I chose that Kenmore model all those years ago. It had a light in the freezer which at the time was a 'high end' feature, and the yellow Energy sticker showed that it was one of the most efficient models at that time. I knew that today's refrigerators would be more energy efficient, but I 'assumed' not so efficient to make it worth replacing the old one. I figured I'd keep the old one until it broke, and I couldn't fix it myself. That changed when I helped someone move and was rewarded with an 18 month old refrigerator;  COOL! Before swapping them I decided to measure how much energy my old fridge used, then install the new to me fridge and measure and compare the two. I used my Kill-a-Watt to measure the energy (every home should have at least one Kill-a-watt).
Well I got a nice surprise. The new fridge uses half the energy as the old one!  As the chart shows the old fridge costs $110 a year to operate, and the new one only cost $55.

I used Google Drive (aka Docs) to create the spreadsheet and chart. If you mouse over the columns the fly over text will show you the exact amounts.

The spreadsheet shows the number of hours and the average (winter and summer) cost per Kilowatt for my utility. The Kill-a-Watt has a timer, and it accumulates the energy used.  So calculating the KW per hour is simple.
There are several reasons why the new fridge is less expensive to operate.
  1. The new fridge is smaller than the old one
  2. The new one does not have an ice maker
  3. There is no light in the freezer
None of those are the major reasons. I suspect the insulation and possibly the motors are smaller and more efficient. I have another device that monitors the kilowatt hours, time (duration), and on time. I'll hook it up and create a profile of energy usage, run time, and room temperature.

I know now that I should have replaced my fridge sooner since at $50+ per year saving, a $1500 refridgerator will pay for itself in 30 years, assuming it lasts that long.