Freezer power consumption

I tested out 25+ year old freezer and our 3 year old freezer for energy usage with the watt meter I bought on ebay.

The old freezer uses 2.8 Kwh per day which is $56 per year.

The new freezer uses 0.82 Kwh per day or $16.40 per year.

But that is not the whole story, the new freezer is larger. In order to compare them equally we have to calculate the size of each, to be accurate I would have to calculate the interior volume, but they are full of food so I calculated the total volume by measuring the length X width X height.

New freezer volume 20,416 square inches.

Old freezer volume 38,016 square inches.

To find out how much energy the old freezer would consume if it were the same size as the new freezer we :   20416 / 38016 X $56 = $30.07

If we take the price of the old freezer’s energy usage per year and divide by the price of the new freezer’s usage we get 1.83 or 183%

My conclusion is that the old freezer uses almost twice the amount of electricity per year but for the extra $14 per year it is not worth buying a new freezer.