Propane Outboards

[delmarrey]

Originally Posted by David M

Gas is such an inexpensive and plentiful resource in this country it's amazing we are not using more of it, over gasoline and Diesel.

If it were only economical to compress natural gas. There's so much of it out there that we sell it to other countries. >>>> NaturalGas.org

http://news.nationalgeographic.com/n...al-gas-export/

[HopCar]

Natural gas would be great if only it would turn to liquid at a low pressure like propane does.

[David M]

From what I have read to compress it is economical. The cost to compress it is still less than the cost of gasoline or Diesel for the equivalent energy content. Do you have a source that says different?

[HopCar]

David I don't know about the cost of compressing natural gas but propane turns to liquid at pretty low pressure and can be stored in pretty light tanks. CNG is stored at very high pressure in tanks similar to scuba tanks.

[delmarrey]

Originally Posted by David M

From what I have read to compress it is economical. The cost to compress it is still less than the cost of gasoline or Diesel for the equivalent energy content. Do you have a source that says different?

NOT!

I use to maintain (2) CNG 4500 psi, (3) 500 gallon vessel, compressors for the City. The (2) cost $100,000 and by the time they had 1000 hours on them they shut them down. They're good for 10,000 hours. They have to be run almost full time to turn enough profit to pay for themselves with all the maintenance and inspections.
All the fittings and hoses are hi-pressure SS and the electronics have to be adjusted with computers.
Another government sponsored R&R project I got to witness. Next were the Toyota Prius.

[delmarrey]

Originally Posted by HopCar

David I don't know about the cost of compressing natural gas but propane turns to liquid at pretty low pressure and can be stored in pretty light tanks. CNG is stored at very high pressure in tanks similar to scuba tanks.

Propane when compressed turns to liquid (LPG) at -44º F.

Propane Facts & Comparison Charts

[HopCar]

Propane when it's not compressed turns to liquid at about -44F. At 70 deg. F propane turns to liquid at about 120 PSI. At 4000 psi natural gas is still a gas and not very energy dense. Natural gas is liquified for bulk transport but it must be carried in cryogenic containers at very cold temperatures.

[rebel heart]

Interesting stuff. I never thought the Torquedos would make much progress but those are pretty awesome. Maybe this will get some legs as well.

[delmarrey]

Originally Posted by HopCar

Propane when it's not compressed turns to liquid at about -44F.

Actually it turns to gas from liquid unless under pressure, above -44º F.
Read this link. >>Propane Facts & Comparison Charts

[HopCar]

Delmarrey, I see what you're saying. Propane will boil at about -44F, It will turn back to liquid just below -44F at sea level. If you increase the pressure to about 120 PSI, it won't boil until about 70F. Think about what happens in a pressure cooker. At normal sea level pressure water transforms to gas at about 212F. If you enclose it in a pressure cooker and raise the pressure the water won't boil until it is much hotter. Conversly if you take your pot of water to a higher altitude and lower the pressure it will boil at less than 212F.