Energy Content of 1 Cubic Meter of LPG at the Meter?

http://en.wikipedia.org/wiki/Propane

Add this

http://en.wikipedia.org/wiki/Heat_of_combustion

(sroll down to see if your application is likely to depend on the upper or the lower heating value, scroll a bit further and there is a nice table for common fuels)

your 30g/cm2 are surely a gauge value. you just have to convert your cubic meter back to standard cubic meters for the math to be correct (30g/cm2 gauge are about 0.3bar, add your atmospheric pressure to get the actual gas pressure. Then use the good old gas laws; pV/ T is constant for a given amount of gas. So you have V_std=p_amb*V_amb*T_std/( T_amb*p_std). Don't forget that you have to express T in Kelvin)

I hope with that the PM has all the necessary info.

Grams/cm is not a unit of pressure. Did you mean perhaps g_f/cm²?

Is this a homework question?

You are correct, I goofed; the pressure out of the gas meter is 30 gm/cm^2.

No, it is not a homework question, but rather a matter of consumerism. How much are we being charged for that slice of energy, compared to other sources, such as electricity.

You can do the conversions but below is a little study I did a few months ago for another CR4 discussion. Of course prices have changes some but you'll get the idea.

My curiosity got the best of me so I ran some figures on the cost per thousand btu's of our three main fuels in western Montana. (we don't have natural gas here on the Rez).

Gasoline 3.59 per gallon /115,000 btu per gallon = .031 per M btu's

Diesel 4.19 per gallon /129,500 btu per gallon = .032 per M btu's

Propane 2.10 per gallon /84,500 btu per gallon = .025 per M btu's

so... .025(propane)/.032(diesel) = .78 which means propane is 22% cheaper than diesel. That translates to dollars in the pocket today, but today only. Who knows what tomorrow will be.

Diesel is good but it has some problems (like if it's green, it's got algae in it and it could cause pollution if it leaks. Natural gas would be ideal except what are you going to do when the supply line is cut from a flood or something else? LNG would be great except for the cost of the tanks. Propane is cheaper, it won't pollute, it won't go bad from long term storage, so...if you're a bean counter and a gloom and doom enviromentalist, there's only one choice. At least, in this part of the world.

This might help:

http://www.engineeringtoolbox.com/fuels-densities-specific-volumes-d_166.html

Check the calorific value of LPG which is generally in kJ/kg or kCal/kg. Covert 1 cu.m of LPG gas in kg (take temp & pressure correction) then you get value like kCal/cu.m. Now convert kCal to kWh (1kWh=830 kCal).

Dear Mr.Pradeep44,

1 KWHr = 860 K.Cal

DHAYANANDHAN.S