Skip to Content
Find More Like This
Return to Search

LNG – Engine Delivery

Idaho National Laboratory

Contact INL About This Technology

Technology Marketing Summary

This is a method of improved delivery of liquid natural gas (LNG) within an engine delivery system. The LNG is first pumped into the insulated holding tank from a fueling station. As a tank is refueled, any remaining natural gas vapors are condensed and returned to the liquid state. This allows the tank to fill quicker and hold more fuel, without having to vent any vapor into the atmosphere.


The tank uses two sections; one for a liquid, and the other for gas vapor section. The fuel system would maintain pressure so that fuel will flow to the engine without the aid of a pump, if desired. To keep the desired pressure within the fuel tank, the natural gas is heated as the pressure decreases so that it will maintain the proper pressure level. Because the holding tank is insulated it allows the liquid natural gas to be stored at the correct temperature for a longer period of time.

Based on the pressure within the holding tank the delivery system automatically chooses what form of gas to withdraw, so that pressure will remain at the correct level. The selected fuel l then passes through a chamber and into a heat coil to be flashed to vapor and then delivered to the engine, and to the holding tank to increase the pressure within as needed.


-        Improves LNG delivery to internal combustion engines.

-        Does not require electronic switch, solenoids, or computers to function.

Applications and Industries

Natural gas, alternative fuel, natural gas engine, liquid natural gas

Patents and Patent Applications
ID Number
Title and Abstract
Primary Lab
Patent 6,921,858
Method and apparatus for pressurizing a liquefied gas
Apparatus providing at least one thermoelectric device for pressurizing a liquefied gas container and methods employing same are disclosed. A thermoelectric device including a heating surface and a cooling surface is used for pressurizing a container by vaporizing liquefied gas within the container by transferring heat energy from a portion of the liquefied gas in contact with the cooling surface to another portion of the liquefied gas in contact with the heating surface of the thermoelectric device to convert some of the liquefied gas to a vapor state. Liquefied gas vapor and/or liquid phase may be supplied by disclosed apparatus and methods. The apparatus may also be used as a vapor pump or a liquid pump, or fluid pump. Methods of operation are also disclosed.
Idaho National Laboratory 07/26/2005
Technology Status
Technology IDDevelopment StageAvailabilityPublishedLast Updated
B-045; 6921858ProductionAvailable09/04/201209/04/2012

Contact INL About This Technology

To: Ryan Bills<>