Looking for a formula!

pitman9

Take the cost of a unit of fuel, multiply it by 100,000.

Now multiply the btus per unit of fuel by the efficiency of the appliance.

Divide the first result by the second result and you have the delivered cost per 100,000btu.

So if gas is $2 a therm and a therm is 100,000 btu and you have a 90% appliance it's:

$2 x 100,000 = $200,000
Divided by
100,000btu x .90 = 90,000btu
gives you $2.22 per 100,000 delivered btu

J. Reid

Looking for a formula!

Looking for a formula for cost savings in switching from LP to Natural. How many therms does one gallon of propane generate vs. Natural gas. Would appreciate any suggestions.

J. Reid

Looking for a formula!

Ok, the conversion of Natural gas is CCF and propane is measured in gallons. What is the conversion of CCF to gallons. I want to make sure I'm converting the same size unit.
Natural gas is .74 for 1 CCF and propane is 1.80 per gallon. So for instance, customer wants a 100,000btu 90% furnace and wants his cost savings from propane to natural gas, how do I figure it out?? Thanks!

STEVEN MARKS

1 gallon of propane = 91,800 btus'
1 therm or CCF of natural gas = 100,000 btu's
amount of fuel to heat house for seaon * price of fuel
annual fuel usage F= (heating load * 24(hours in a day)* degree days) / (boiler efficiancy * heating value of fuel btu's * design temp difference)

Steve Ebels_3

It's the btu's

You have to compare the btu's per unit, whatever that unit may be. Roughly, the btu's per unit are as follows;

Natural gas is 100,000 btu's per therm or CCF

Propane is 91,000 btu's per gallon

#2 Fuel oil is 139,000 btu's per gallon

Here's an equation using LP at a cost of $1.50 per gallon

$1.50 = 91,000 or N = 100,000

It goes like this $1.50 x 100,000 = 150,0000 then

150,000 / 91,000 = 1.65 or $1.65 per 100,000 btu's

Now divide that by an 85% efficient appliance for example and you get your true cost per 100,000 btu's delivered to your space. $1.65 / .85 = $1.94

Just substitute the numbers that you have to deal with locally and you'll find your answer quickly. Or post them up here and I'll crunch them for you.

pitman9

Okay, then it's:

> Ok, the conversion of Natural gas is CCF and

> propane is measured in gallons. What is the

> conversion of CCF to gallons. I want to make

> sure I'm converting the same size unit. Natural

> gas is .74 for 1 CCF and propane is 1.80 per

> gallon. So for instance, customer wants a

> 100,000btu 90% furnace and wants his cost savings

> from propane to natural gas, how do I figure it

> out?? Thanks!

pitman9

Okay, then it's:

$1.80 x 100,000 = $180,000

Divided by

92,000 x .85 = 78,200

giving a cost per 100,000 delivered btus of $2.30 for LP



$0.74 x 100,000 = $74,000

Divided by

100,000 x .90 = 90,000

giving a cost per 100,000 delivered btus of $0.82

So the new natural gas unit would cost around 36% as much to operate as the old LP unit.

Steve Ebels_3

I take it that

Your LP cost is $1.80 per gallon and your natural gas is $.74 per therm? If so you are correctamundo.