showerhead savings calculations

These calculations display your estimated savings based on assumptions below

For customized calculations enter your own data in the green fields

average shower head
Flow Rate
gallons per minute
number of people showering
length of showers mins
mins
mins
total shower use per day mins
type of water heater

water heater efficiency %
temp of hot water °F
temp of cold water °F
hot water %
cold water %
shower water temperature °F
1000 US gallon = 133.680556 cubic feet
fresh water cost
(kgal) cost per 1000 gals fresh
or
(HCF) cost per 100 cubic feet fresh
waste water cost
waste water processing

(kgal) cost per 1000 gals waste
or
(HCF) cost per 100 cubic feet waste
cost per kilowatt hour
cost per therm
cost per CCF
cost per cubic meter
1 CCF = 103,100 BTU = 1.031 therm
1 m3 = 35.31 ft3 = 0.3531 CCF

How your savings are calculated

Step 1 find cost per gallon

$2.80 fresh water + $2.80 waste water = $5.60 per 1000 gallons

$5.60 / 1000 = $0.0056 per gallon

Step 2 find daily gallon usage

30 mins x 2.5 gallons per min = 75

30 mins x 1.5 gallons per min = 45

Step 3 find the difference in gallons used

75 - 45 = 30 gallons savings

Step 4 find the cost savings in water

30 x $0.0056 = $0.1680 water savings per day

Step 5 find the number of heated gallons of water

75 x 60% = 45 gallons of heated water per day

45 x 60% = 27 gallons of heated water per day

Step 6 find the number of degrees of heating water

140 water heater temp - 57.5 cold water temp = 82.5 degrees

Step 7 multiply the number of degrees by the 8.337 BTUs it takes to heat one gallon of water one degree

8.337 BTUs x 82.5 degrees to raise by = 687.8025 BTUs to heat 1 gallon to desired temp

Step 8 take into account the hot water heater efficiency

687.8025 BTUs / 85% = 809.1794

Step 9 multiply your efficiency adjusted BTUs by the number of gallons to be heated

809.1794 BTUs x 45 gallons to heat = 36,413.0730 BTUs per day

809.1794 BTUs x 27 gallons to heat = 21,847.8438 BTUs per day

Step 10 convert BTUs to therms

36,413.0730 / 100,000 = 0.3641 therms per day

21,847.8438 / 100,000 = 0.2185 therms per day

Step 11 covert therms to kilowatt hours for electric water heaters

0.3641 therms per day x 29.3071 KWh per therm = 10.6707 KWh per day

0.2185 therms per day x 29.3071 KWh per therm = 6.4036 KWh per day

Step 12 find the cost of heating water with electric

10.6707 daily KWh use * $0.118 cost per KWh = $1.2591 per day cost

6.4036 daily KWh use * $0.118 cost per KWh = $0.7556 per day cost

Step 13 find the difference in electric savings

$1.2591 - $0.7556 = $0.5035 electric savings per day

Step 14 add the water and electric savings

$0.5035 daily electric savings + $0.1680 daily water savings = $0.6715 daily savings

Step 15 find yearly and lifetime savings in dollars with electric

$0.6715 x 365 = $245.10 yearly savings with electric

$245.10 x 15 year estimated life = $3,676.46 estimated lifetime savings with electric

Step 16 find yearly and lifetime electric savings

10.6707 - 6.4036 = 4.2671 daily KWh savings

4.2671 x 365 = 1,557.5 yearly KWh savings

1,557.5 x 15 year estimated life = 23,362 lifetime KWh savings

Step 17 find yearly and lifetime water savings

30 gallons daily water savings x 365 = 10,950 gallons yearly water savings

10,950 x 15 year estimated life = 164,250 lifetime water savings

$0.1680 daily water savings x 365 days = $61.32 yearly water savings

Savings calculations are presented as an example of potential savings; actual savings may vary based on use, utility rates and other factors. Calculations are based on national averages and assumptions and may be adjusted for a more accurate estimate of individual savings. While EnergyEarth strives to provide the most accurate information, we cannot guarantee the savings displayed.