I have a large volume of (free) natural gas sitting at 5,000 psi. I'd like to pass the gas through an orifice, give it room to expand on the backside, and use that to chill glycol. I would like to drop the output pressure to 100 psi in the process. I wish to use the chilled glycol to cool my home in the summer months, and the lower (output) gas pressure for other purposes. Excess gas will vent to atmosphere. Most common refrigerants only need a pressure differential of 150 psi or so to do their work. With my natural gas, will the btu chilling effect be proportional to the 4900 psi pressure drop? In other words, do I gain anything from starting out with such high pressure? As it comes from a well, I suspect the temperature of the gas is around 60 degrees F. To equal the equivalent of 6 tons of (conventional) cooling capacity, what am I looking at in terms of orifice/expansion chamber size? Thanks for any input.