In floor cost ele nat cost?

[dodge em]

I have in floor heat, 15x30 building with some insulation R6 pannel board celling, r13 walls, insulated doors and 2" under floor (best i can do toady, would like to blow in over the board)

. I am using a 15gal 6,000watt ele heater and it is running me $200 month to keep it at 58*f by calculation its running for 20min every hr.

What would i expect to pay to heat with a 36,000btu nat gas 40gal? $10.50cmf.
I took it off the stat and put it on a timer so i can controle my bill for the moment but i am unsure of the temp drop im going to see. I have it on for 15min every 2 hrs and that will still be $75 a month. Guess...

[regguy1]

Originally Posted by dodge em

I have in floor heat, 15x30 building with some insulation R6 pannel board celling, r13 walls, insulated doors and 2" under floor (best i can do toady, would like to blow in over the board)

. I am using a 15gal 6,000watt ele heater and it is running me $200 month to keep it at 58*f by calculation its running for 20min every hr.

What would i expect to pay to heat with a 36,000btu nat gas 40gal? $10.50cmf.
I took it off the stat and put it on a timer so i can controle my bill for the moment but i am unsure of the temp drop im going to see. I have it on for 15min every 2 hrs and that will still be $75 a month. Guess...

1000 Cu Ft of natural gas contains 1,000,000 BTUs so the 36K BTU / HR heater can burn for 27.77 hours on 1000 Cu Ft NG. So it should cost slightly under 40 cents per hour (at 10.50 per 1000 CF) that the burner is on. How many hours per day need to mantain temp...? your guess.

Using your burn time estimate:
15 min every 2 hr. would be 3 hours per day burner is on x 30 = 90 hr / month x .40 = $36.00 per month.
At the 20 min / hr figure it would burn 240 HRs / month = $96.00

sounds cheap. Disclaimer: Your Results May Vary !!

[dodge em]

Ok. So if i maintain my status as of yeaterday, that was on for 20min every hr. and upgrading to gas thats roughly $85mo based on the above and my calculations.
i would have more water vol (would help right?)and i would have an additional 15,522bts with the gas apposed to the 20,478btu @ 6kw. so it should run less to keep the garage at 60*f but there is a loss with the gas efficency tho. 20%? so they may pull me below the 20,000btus.

i called the gas company and asked a few q's above said idk sry.

[regguy1]

Originally Posted by dodge em

Ok. So if i maintain my status as of yeaterday, that was on for 20min every hr. and upgrading to gas thats roughly $85mo based on the above and my calculations.
i would have more water vol (would help right?)and i would have an additional 15,522bts with the gas apposed to the 20,478btu @ 6kw. so it should run less to keep the garage at 60*f but there is a loss with the gas efficency tho. 20%? so they may pull me below the 20,000btus.

i called the gas company and asked a few q's above said idk sry.

The BTU rating is the input, that's how much gas it will consume. The output depends on efficiency of the heater. The input rating will determine consumption. Base your calculations on that. I have a 45K BTU in my garage, but the output is about 36K @ 80% effiecency. The water volume might be a factor but I'm not sure how to evaluate it.

Bottom line is gas will most likely be 40-50% cheaper (hopefully)

[regguy1]

Some interesting stuff, The btu to watts conversion might help you to compare gas / electric costs.

Link:
http://en.wikipedia.org/wiki/British_thermal_unit

In natural gas, by convention 1 MMBtu (1 million BTU, sometimes written "mmBTU") = 1.054615 GJ. Conversely, 1 gigajoule is equivalent to 26.8 m3 of natural gas at defined temperature and pressure. So, 1 MMBtu = 28.263682 m3 of natural gas at defined temperature and pressure.
1 standard cubic foot of natural gas yields ≈ 1030 BTU (between 1010 BTU and 1070 BTU, depending on quality, when burned)
[edit] Associated units
The BTU per hour (BTU/h) is the unit of power most commonly associated with the BTU. The term is sometimes shortened to BTU hour (BTU.h) but both have the same meaning.

1 watt is approximately 3.41214 BTU/h[4]
1000 BTU/h is approximately 293.071 W
1 horsepower is approximately 2,544 BTU/h
1 "ton of cooling", a common unit in North American refrigeration and air conditioning applications, is 12,000 BTU/h. It is the amount of power needed to melt one short ton of ice in 24 hours, and is approximately 3.51 kW.
1 therm is defined in the United States and European Union as 100,000 BTU—but the U.S. uses the BTU59 °F whilst the EU uses the BTUIT.
1 quad (energy) (short for quadrillion BTU) is defined as 1015 BTU, which is about one exajoule (1.055 × 1018 J). Quads are used in the United States for representing the annual energy consumption of large economies: for example, the U.S. economy used 99.75 quads/year in 2005. One quad/year is about 33.43 gigawatts.
The BTU should not be confused with the Board of Trade Unit (B.O.T.U.), which is a much larger quantity of energy (1 kW·h, or about 3412 BTU