Coastal Solar Technology
Home Owner Savings Calculation
Based on FSEC (Florida Solar Energy Council) Studies
Hot water usage assumption based on energy usage studies:
1st person uses 20 gallons per day. 15 gallons per day for each additional
person in the household. In this example we are going to use a 4 person
Lets assume your inlet water temperature is 70 degrees
and your outlet temp is set to 120 degrees. Remember this computation
is for 4 people in the household (65 gallons per day).
We now need to add 20% to this total which compensates for heat loss
in the tank and the pipes.
Now we need to convert BTU's (energy) into kWh (Kilowatt Hours) so
we can compute the cost of the energy required to heat your water.
To convert BTU's to kWh: BTU's/3413 x .9
The .9 is for electric heaters where there is an assumed 90% efficiency.
If you use gas use .6 as gas tanks have only a 60% efficiency.
- 32526 / (3413 * .9) = 10.6 kWh per day. Multiply by your
10.6 kWh by 365 to get your kWh per year usage = 3866 kWh per
Lets assume electricity in your area cost $.08 per kWh You can get
the exact figure from your electricity company.
- 3866 kWh* .08 = $310 per year to run your water heater.
Solar will save at least 80% of this bill. Your hard cash savings
on using one of our solar water pre-heaters will be $250 per year.
In addition, our heaters increase the hot water capacity of your home
by 35-50 gallons. Never run out of hot water again. It also provides
hot water during power outages using out 3-way system.
This figure does not include the reduction of carbon emissions
into the atmosphere, the reduction of our dependence on foreign oil,
or other intrinsic factors. This is the American thing to do. Your savings
begin immediately and our solar collectors have a 30 year lifespan.
Your savings after 30 years, not figuring the inevitable increased
cost of energy.
How many appliances do you have
in your house that will make you money as time progresses?