According to the U.S. Energy Star website, a run-of-the-mill hot / cold bottled water cooler can suck back more electricity than a large refrigerator. That's a lot of energy for an appliance that only provides you with water.
If you find an Energy Star-compliant model, it will thankfully only need about half as much energy as a standard water cooler. It will also have met strict guidelines for energy efficiency, set by the EPA (Environmental Protection Agency) and the U.S. DOE (Department of Energy). A good indication you're in the right place is if the seller puts Energy Star claims front and center. It's likely they know the value of efficiency and will have several choices in that line.
Energy Star criteria include:
Money savings will work out to about $5 to $10 per year for a cold-only dispenser and up to $50 per year for a water cooler with hot and cold dispensers. You'll easily save the difference for a more expensive Energy Star water cooler in as little as a few years, and after that, it's all money in the bank.
Plumbed-in water coolers need not apply
Also called bottleless water coolers, plumbed-in systems aren't currently covered under Energy Star. If you are mathematically inclined, you'll have to figure out their running costs yourself to make a comparison.
Companies in compliance
Well-known water cooler brands like GE and Whirlpool are getting in on the energy-savings action. If you purchase your water cooler at a store, look for one that is clearly labeled "Energy Star." If it's from a dealer, ask for a model that won't require unnecessary electricity usage. Comparing more than one energy-efficient product can help you find the one with the lowest possible operating cost.
Don't give in to low-price temptation
It will be tempting to buy the water cooler that is initially lower in cost, but you'll end up regretting it if you have to pay more to run it. Energy efficiency shouldn't be compromised, it should be a necessity.
Visit the Energy Star website at www.energystar.gov