What does it cost to take a ten-minute shower in the morning!
You will be surprised the amount of money you can save each year, changing out your standard showerheads for a more energy efficient low-flow showerhead. You must remember the amount of wet you get doesn't change, just the amount of water waste. We are close to Minneapolis, MN so we will use this data for our example.To calculate the cost we need to know some things:
The cost of water in your city
The average cost of electricity per kilowatt hour (kWh)
The average cost to heat 1 liter of water
The average flow rate of your showerhead
The flow rate of a new low-flow showerhead.
A Residential shower:
The average cost of water in Minneapolis, Minnesota USA is $3.20 per unit (748 gallons).
This equals $.004278 per gallon or $.0011302 per liter. (3.785 liters = 1 Gallon).
Info Here
The most recent figure for average cost of electricity (2011) in the Minneapolis is 10.3 cents ($.103) per kilowatt-hour (kWh).
Info Here
Cost to heat one liter of water to average showering temperature is equal to $.103/kWh.
Multiplied by the "cost to heat one liter of water to average showering temperature" factor $0.1313685. Equals $0.013531 to heat one liter of water.
Info Here
Most regular showerhead fixtures installed before 1992 have flow rates of up to 5.5 gallons of water per minute. We will use is 3.5 gallons/minute for this example.
Info Here.
Using the information from the websites (linked above), we can do the math:
Cost of 1 liter of water:
$.0011302Cost to heat 1 liter of water:
$.013531The average cost of 1 liter of heated water:
$.0146612 (almost 1.5 cents)How many liters of water are used in the average ten-minute shower?
The flow rate of our showerhead uses 3.5 gallons per minute.Their are 3.785 liters in each gallon.
This is 13.2475 liters per minute, or 132.475 liters in ten minutes.
The cost of a 10 minute shower is:132.475 liters, multiplied by the cost per heated liter of water $.0146612, or $1.9424 for the average ten-minute shower in Minneapolis, MN.
If one person showered once a day for ten minutes the cost for one month (30 days) would equal: $58.27 per month.
So how much can you save?
Just by changing out your old shower head and replacing it with a new low-flow showerhead that reduces the flow rate to 1.5 gallons per minute, you can lower your cost per shower to $.8324, and save you approximately $1.11 per shower. If you shower 30 times a month on average that is a monthly savings of $33.30 per family member.