Replacing a working fridge saves money on electricity only if the new one uses noticeably less energy. The savings are easy to estimate once you know both yearly energy figures.
Look for the yellow EnergyGuide label (often inside the door or in the manual), which gives yearly kWh from the standard test. Older fridges may have lost efficiency since they were tested. A plug-in energy meter left on for a week or two, scaled up to a year, gives a figure for your own fridge.
Choose the same type and a similar size. A certified bottom-freezer fridge is a fair swap for a bottom-freezer fridge; moving to a larger or different layout can cancel the savings. The median certified top-freezer fridge uses 363 kWh a year and the median bottom-freezer uses 563 kWh.
Yearly operating savings = (old kWh − new kWh) × your price per kWh. For example, going from a fridge using 700 kWh a year to one using 400 kWh saves 300 kWh, about $54 a year at 18.16¢ per kWh, or about $545 over 10 years if prices stay the same. These example figures are for illustration only; use your own.
ENERGY STAR estimates that properly recycling an old refrigerator and replacing it with a new certified one can save about $150 over the 12-year lifetime of the product.
Keeping the old fridge running in a garage as a second fridge adds its full running cost, not saves it.
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