Aaron Klein

While many water saving campaigns target tangible water use, such as washing your car or watering your lawn, you indirectly use water throughout the day without even thinking about it.  Whether your realize it or not, the electricity coming to your house is on-demand, it’s not stored in a battery waiting for you to turn on the lights; electricity is generated when you request it.  This means if you use less electricity, power generation directly decreases.  Fossil fuel based power generation especially uses large amounts of water for cooling. What many people don’t realize, then, is that using unnecessary electricity IS using unnecessary water. 

Most power generation in the U.S. falls under thermal electric power generation, in which water is boiled to spin a steam turbine.  Any combustion power generation, even nuclear and some forms of solar use this method.  The problem is this water must then be cooled.  When water runs through a cooling tower water is evaporated and is lost.  “In thermoelectric plants, 0.47 gal (1.8 L) of fresh water is evaporated per kWh of electricity consumed at the point of end use.” What does this water use look like?  A standard CFL light bulb (that’s the lightbulb that’s good for the environment) could be 45 watts.  A 45 watt lightbulb uses 0.02115 gallons of water per hour of use.  If you work 8 hours per day and commute 30 minutes each way, you could easily be gone for 9 hours.  Leaving that lightbulb on while you are at work would use 0.19035 gallons of water.  My small apartment has 10 lightbulbs.  Say I left the lights on all day that’s almost 2 gallons of water.

       

What if you don’t even have CFLs?  The 0.19035 gallons more than doubles! Let’s look at an appliance; a standard dryer is 4400 watts.  This means a 45 minutes cycle is 3.3 kWh, that’s 1.55 gallons of water.  A washing machine would use approximately 0.26 gallons of water per load (excluding its physical water use). You can view the power consumption of appliances around your own home here.

 

How can you use this information to save water?  Its simple use less electricity.  You can make sure to turn off lights when you leave the room, do a quick sweep of your living space before leaving for work to make sure all the lights are off.  If you don’t yet have CFL light bulbs switch now, depending on your current set up CFL light bulbs could be more than twice as efficient, saving water and your electricity bill.  Plan out your laundry: if you can do one load of laundry rather than two you would save approximately 1.81 gallons of water.  These washing strategies will directly save you money if you use coin operated machines.  You can even try air drying your clothes, its free and green.  Think about your heating and cooling habits; this means wearing clothes that allows you to have a more neutral thermostat setting.  On a hot day don’t try to make your living space icy cold. On a cold day lower your thermostat and layer your clothing.  In general if you have an opportunity to save electricity take it because you are also saving water.