Pool Heating, Compare the Cost of Different Fuels

When considering a boiler (furnace) for heatingthe deep end is 6 feet and the shallow end is 3
your pool, what fuel should you choose?feet, the average is 4.5 feet.
The first thing to consider is fuel storage, unlessThat make the area time the av. depth = xx
you have a piped gas supply you will need tocubic feetexample 500 (area) x 5 (av depth)=
have a tank for either heating oil or propane,2500 cubic feetto convert that figure to gallons
(LPG)multiply by 7.5 = 18750 gallonsand to get pounds
The types of boiler that you could choose areof water multiply by 8 = 150,000 pounds.
limited to those that burn fossil fuels directly, asNext you need to look at boiler efficiency, and
above, or electric, which are not really suitable forusing british government figures for new
pool sized volumes of water, unless they are ofcondensing gas boilers a 91% efficiency can be
very high wattage.expected the figure for LPG (propane) is better
Of the standard gas and oil burning boilers youat about 93% while oil boilers are up to 97%. The
would need to compare both the fuel costs, andfigure that you use will depend on the make of
the efficience of the boiler to make a soundboiler you decide on, and the official figures, but
comparison.what it means is a 100,000 btu boiler with a 91%
Basic Facts:efficiency will produce 91,000 Btu.
- BTU = quantity of heat required to raise theIf the water temperature is 68 f (20c) and you
temperature of 1 pound of water 1 degree F.want to raise that to 92f (30c) a 24f rise in
- 1 Therm of Natural Gas = 100,000 BTU'stemperature you multiply 150,000 pounds of
- 1 Gallon of Propane = 91,000 BTU'swater by 24 degrees and get a requirement for
- 1 Gallon of fuel oil = 130,000 BTU's3,600,000 Btu'sa 100,000 btu natural gas boiler at
- 1 Gallon of Water Weighs 8.00 pounds91% efficiency would burn for more than 39
- 1 cubic foot of water = 7.5 gallonshours and burn 3.6 therms of gasa 100,000 btu
The first figure you need to work out is the areapropane boiler at 93% efficiency would burn for
of your pool, If it is rectangular that is a simplemore than 38 hours and burn 40 gallons of
length x width.if it is circular use the formula pipropanea 100,000 btu oil boiler at 97% efficiency
times radius squared or half the width x half thewould burn for more than 37 hours and burn 28
width x 3.14it is better to over estimate yourgallons of oil
pool size for these fuel cost calculations.Substitute your figures in to the calculations and
The second figure that you might want is theuse current prices to see what your costs would
volume of the pool which is the area as workedbe.
out above multiplied by the average depth, so if