Most offices have at least one water cooler and many of these have both a 'chilled water' and 'boiling water' function. So how much energy do they actually use?
The actual energy consumption of your water cooler will depend on how it is used, and how many people are using it. The only way to know the actual energy consumption of your water cooler is with a plug in power meter.
Here are our test results...
Power consumption of our office water cooler
Most office water coolers are using energy to keep water cool (and hot) continuously. This doesn't make much sense unless the office is open 24 hours a day.
At the Steplight office we use a simple plug in appliance timer so that the water cooler is only on during office hours. The timer is set so that the water cooler will come on an hour before anyone arrives and turn off when everyone leaves. (Timers can be purchased from a hardware store for less than $20.00). We also have the hot water function turned off.
We ran some tests using our appliance power meter to find the actual energy consumption of our water cooler (with and without the timer).
To get an accurate understanding of the water cooler's energy consumption we need to run the test over a 24 hour period. This is because just like a fridge or washing machine, the water cooler won’t be using a fixed amount of electricity (it cycles on and off).
We're a pretty small office of up to six people. In larger offices expect the savings to be much greater than below.
1. With timer, cold water only = 0.2 kWh/day
The water cooler used 0.2 kilowatt-hours in a 24 hour period, which equates to around 81 kilowatt-hours ($19.00) per year. The water cooler was using power for 2 hours and 15 minutes of the 24 hour period.
2. Without timer, cold water only = 0.3 kWh/day
The water cooler used 0.3 kilowatt-hours in a 24 hour period, which equates to about 109 kilowatt-hours ($26.00) per year. The water cooler was using power for 3 hours and 5 minutes of the 24 hour period.
3. With timer, cold and hot water = 1.9 kWh/day
The water cooler used 1.9 kilowatt-hours in a 24 hour period, which equates to about 693 kilowatt-hours ($166.00) per year. The water cooler was using power for 6 hours and 28 minutes of the 24 hour period.
4. Without timer, cold and hot water = 2.8 kWh/day
The water cooler used 2.8 kilowatt-hours in a 24 hour period, which equates to about 1022 kilowatt-hours ($245.00) per year. The water cooler was using power for 10 hours and 43 minutes of the 24 hour period.
What to do?
As shown above, using a timer switch is a simple and cost-effective change, no matter how much the cooler is used.
If you have a water cooler with a hot and cold option, consider deactivating the hot water option. This will yield the biggest savings. A kettle used only when needed would be a better option.
If you already have a fridge, why not switch the water cooler off completely, and a keep a filtered water pitcher in the fridge.
If you are still considering getting a water cooler then keep in mind the energy rating. Energy star qualified water coolers are about 50% more efficient than typical water coolers. To qualify for the energy star label, units that cool only must use less than 0.16 kilowatt-hours per day. Hot and cold units must use less than 1.2 kilowatt-hours per day. If you are leasing the water cooler, ask your supplier about energy efficient options.
Energy Rating Guides
When buying any new equipment a good site to check out is the E3 energy rating website. Unfortunately, it doesn’t rate water coolers yet. It does state that there are an estimated 450,000 water dispensers in use in Australia, consuming approximately 350 GWh of electricity every year (this includes bottled water and mains connected water). Since the market for these products is steadily increasing, annual energy consumption by water dispensers is projected to reach 570 GWh by 2020 without intervention.
And that's just the humble water cooler!
If you're interested in assessing energy usage yourself see our wireless energy monitors. Alternatively, we also offer business energy audits to professionally review your site's energy consumption.
- Holly Lovell-Smith