Here at the Consumer Electronics Show in Las Vegas, companies like GE and LG are showing off appliances that should be able to cut into your electric bill. But before you run out and pick one up, there are some things you’ll need to know first.

The most important thing you need to look into is that electric meter tacked onto the side of your building. If your electric company hasn’t installed a smart meter (i.e., a meter that communicates detailed usage information back to the utility company) that uses ZigBee wireless for communicating, these new appliances won’t be of any more use than the latest Energy Star-certified models. The best thing to do is contact your local electric company and find out if you’ve been upgraded to a smart meter and if there are plans to upgrade in the near future.

A GE rep estimated that most homes in the U.S. will have been upgraded to smart meters by 2020.

If you are fortunate enough to have a smart meter, then you’ll need to know exactly how these machines work to save you money and to use energy more efficiently.

Imagine you go to start a load in the GE Brillion dishwasher. If the device senses that this is a peak (and therefore expensive) time to run a dishwasher, it will suggest that you delay the load until a time when you’ll get the most bang for your buck. It is also set to automatically air dry dishes in times of peak use. Of course, if you need clean dishes now, there’s nothing stopping you from running the load immediately.

The Brillion washers and dryers have this same delay system and they have the option of running low-energy cycles if operated during peak hours. The Brillion refrigerator delays defrost cycles until non-peak hours.

GE’s GeoSpring hybrid electric water heater operates only in heat-pump mode during periods of peak costs. The company claims this reduces wattage by over 80% compared to a standard electric-tank water heater.

The company will also be selling its Nucleus Energy Manager for around $200. It’s a small device that communicates wirelessly with both your meter and all your smart appliances, even non-GE ones. Through your home computer, you can use the Nucleus’ interface to not only manage those appliances, but also monitor your electricity usage and time-of-use rates for your electricity.

What’s left for you to decide is whether or not the extra initial investment in a smart appliance is worth the long-term savings. Prices are not currently available, but the GE rep says that the incremental price increase between a Energy Star-certified and the smart, Brillion appliance will be about the same as the difference between a standard appliance and an Energy Star-certified one.

So if you’re someone who keeps appliances for more than five years, and if you’re not constantly overriding the energy-saving settings, then you should have no problem getting back that initial extra cost on the appliances.

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