Assuming you aren’t playing video games at this very moment, it’s quite likely that your console of choice is sitting on a shelf or entertainment center, powered down, waiting for your return. By all rights, that console shouldn’t be sucking down huge amounts of electricity, right? I mean, it’s just sitting there. Sure, there’s a red light indicating that the thing isn’t broken, but how much energy is needed to power that stupid little indicator?

According to a new study from researchers at Carnegie Mellon University, that console (and millions of others like it) is still pulling down vast amounts of power, to the tune of $1.24 billion every year.

The underlying problem here is that modern consoles, unlike the classic 8- and 16-bit machines we grew up with, never actually power down completely. Unless you physically unplug the thing or flip a switch on the power strip it’s anchored to, your PlayStation 3 or Xbox 360 merely goes into idle mode when you instruct it to shut down. While idle the machine does drain far less energy than it would if you were playing Halo or Uncharted, but given that the consoles are often left in this idle state for hours or days at a time, the study claims that 68 percent of all energy consumed by gaming machines is devoured when they’re seemingly inactive.

As a result, idle American gaming consoles used 10.8 terawatt hours of energy in 2010, which translates to a total energy cost of more than $1.24 billion dollars.

That figure is a bit too astronomical for the average person to comprehend, so let’s put it this way: According to the study (PDF), if Sony and Microsoft were to implement automatic shutdown protocols in their machines that actually curtail energy consumption, the average console could pull down an estimated 75 percent less electricity, saving the average user between $30 and $100 annually.

Not mentioned in the study, though likewise beneficial, are the savings this would generate in pure console longevity. If the machine is truly off, it isn’t coursing with electricity. Less electricity means less wear and tear on the console, which translates to a longer lifespan for the machine. Those of you on your third or fourth Xbox 360 know exactly how frustrating it is to have to shell out for a new system when your old one suddenly decides to give up the ghost.

In the meantime, those of you interested in lessening your energy consumption can take very simple steps to ensure that your idle consoles aren’t costing you money. When you’re done playing, simply unplug the system from the wall (making sure to power it down properly beforehand). If you’re using multiple consoles, plug them all into the same power strip, then flick the switch on the strip to kill power to all of its attached devices. It’s an extra few seconds of work, but think of it this way: If you spend an extra few seconds shutting down your console properly, over the course of a year you will have saved enough cash to buy a brand new game (or a really ugly pair of pants).