iStock photo

Maybe this scene sounds familiar: It's Thanksgiving, you're sitting and watching the football game, and you want a beer. So what do you do? If you're like many Americans, you won't go over to the kitchen fridge, which is now crammed with leftovers. Rather, you'll trek down to the basement or out to the garage to the second refrigerator (aka, the "beer fridge").

Sure, it's convenient. But the growing trend of having second refrigerators is a major national energy blight -- not only wasting a lot of energy, but also potentially costing you hundreds of dollars.

From an energy standpoint, second refrigerators are bad news. The simple reason? They tend to be ancient. In fact, nearly 15 percent of U.S. homes have a second refrigerator that is at least 20 years old, which means it is virtually certain to be an energy hog when compared with today's models.

Refrigerators are an appliance category that has seen very dramatic strides in energy efficiency in recent years, thanks to an ever tougher set of state and national energy standards, most recently tightened by the Department of Energy in September. "A fridge that just meets the new standards will use $215 to $270 less per year in electricity than a comparable unit that met the first state standards set in 1978," writes Marianne DiMascio of the Appliance Standards Awareness Project (ASAP).

Here's a chart, from the ASAP, showing just how dramatic progress has been. As you see in the blue line, our fridges are bigger today. Yet as you seen in the red and green lines, both the cost and the amount of energy they consume have declined dramatically.

This can only be called an incredible success story -- one that has been enabled both by regulators but also by technical innovation. Strides in refrigerator efficiency have been driven by many important improvements, including better insulation, more efficient compressors and motors, and better temperature controls.

But, for precisely that reason, by taking an old fridge and putting it strictly on beer duty, you're sacrificing a dramatic amount of progress.

"The typical second refrigerator might be 15 years old when moved to the basement or garage, and might last 5 to 10 more years there," says Steven Nadel, executive director of the American Council for an Energy Efficient Economy. "Most second refrigerators are plugged in all year, but many are really only used for a few big parties, as well as to keep some extra drinks cold."

Nadel adds that these older refrigerators, aged 15 to 25 years, will use some 750 to 1000 kilowatt-hours (kWh) of energy each year. "At the national average electric rate of about 13 cents per kWh, this works out to about $97-130 per year," he notes.

And there's another problem. Because most second refrigerators tend to have started out life as a first refrigerator, they've probably ceded a prized space in the kitchen and instead wound up in the basement, the garage, or even outdoors. That means the refrigerator may have to battle the elements in order to do its job -- which, in turn, means using more energy, especially in summer.

Most significant of all, though, is that by keeping an old refrigerator as a second refrigerator, you nullify any energy advance that was gained when you went out and bought a newer, much more efficient fridge.

According to the EPA, replacing an old refrigerator with a new Energy Star unit can save $ 50 per year and 400 kilowatt-hours in energy use. But for each household that buys a new Energy Star fridge, but then shifts its old refrigerator to the basement, that's one more household whose energy footprint just increased, rather than decreasing.

Environmental Protection Agency Administrator Gina McCarthy mentioned "the war on coal scenario" at a Christian Science Monitor breakfast Monday, asserting that "the energy world is in a transition" partly due to natural gas. (The Christian Science Monitor via YouTube)

"One large refrigerator is cheaper to run than two smaller ones," adds the state of California's Consumer Energy Center. The Center also notes that a refrigerator that is full of food is better at retaining a cold temperature than a refrigerator that is relatively empty -- another fact that makes the occasionally stocked "beer fridge" problematic.

Nonetheless, second refrigerators seem to be quite prevalent, and may even be growing more so.

Based on data from the Department of Energy's 2009 Residential Energy Consumption Survey (which is the most recent installment), it seems to be only relatively recently that U.S. households have seen an upswing in second refrigerators. From 1978 to 1997, their prevalence in households only increased by 1 percent, from 14 to 15 percent. But from 1997 to 2009, they further increased to 23 percent, as shown in this chart of changing American appliance use (second refrigerators are the purple line):

U.S Energy Information Administration, 2009 Residential Energy Consumption Survey.

And the number of second refrigerators may have continued to grow since 2009. Another Department of Energy study put the prevalence of second refrigerators in homes even higher -- at 26 percent -- and suggested their penetration in households is growing at 1 percent per year.

Second refrigerators seem to be most popular in the Midwest, where they were in nearly 30 percent of homes as of 2009 -- but from 1997 to 2009 they grew in popularity in all areas. The states where they're the most popular are Kansas, Nebraska, New Jersey, North Dakota, and Wisconsin.

Who keeps a second fridge? According to EPA, owners of older, less efficient refrigerators (second refrigerators or otherwise) are actually often younger, well to do couples. "The size of the home appears to be the biggest indicator of having multiple refrigerators, while the age of the home seems to have little influence," adds another study. "The length of time in the same residence is also a large influence, possibly indicating that people simply keep their old unit when a new one is installed."

So what's the alternative? Refrigerator recycling, which is supported not only by the Energy Star program but also by many utilities across the country, some of which offer cash or a bill credit in exchange for turning in an old fridge. According to Energy Star, recycling an older or second refrigerator properly can lead to savings of $ 300 to $700 over a five year period, and avoid up to 20,000 pounds of greenhouse gas emissions.

So for the sake of the planet and your own energy bills, please reconsider whether you really need a second fridge (especially an older one). And for the sake of your gut, buy your beer one six-pack at a time.