Underground compressed natural gas storage and service system

Underground compressed natural gas storage and service apparatus comprising:

• a plurality of storage containers, each container including:
• a gas vessel having a perimeter wall enclosing an inner cavity, said perimeter wall having a top end, a bottom end and a body portion connecting said top end and said bottom end together, said bottom end and at least a substantial portion of said body portion being positioned underground, said top end having an opening therein for allowing compressed natural gas to flow into and out of said inner cavity;
• a reinforcing sheath surrounding said bottom end and said portion of said body portion of said perimeter wall being positioned underground;
• and
• a siphon line extending through said top end of said perimeter wall into said inner cavity of said gas vessel for removing contaminating material from said inner cavity;
• a compressor for compressing natural gas for storage in said storage containers;
• and
• first conduit means for conducting compressed natural gas from said compressor to said storage containers and from said storage containers to a location separate therefrom.

A method of installing an underground compressed natural gas storage apparatus having a predetermined gas volume capacity comprising:

• determining the desired gas volume capacity of the storage apparatus;
• drilling a borehole into the earth, said borehole having a depth and diameter sufficient to accommodate the desired gas volume capacity of the storage apparatus;
• selecting a unit of oil field casing having a cylindrical outside surface, an inner cavity, an open upper end, an open lower end, a body portion connecting said upper end and said lower end together, and a length and diameter sufficient to accommodate the desired gas volume capacity of the storage apparatus;
• sealing said lower end of said unit of casing to prevent compressed natural gas from leaking therethrough;
• running said unit of casing into said borehole to a depth such that said sealed lower end and at least a substantial portion of said body portion of said unit are positioned underground;
• injecting hydraulic cement into said borehole to form a cement sheath between said outside surface of said unit of casing and the wall of said borehole;
• positioning a siphon line having a top end, a bottom end and a body section connecting said top end and bottom end of said siphon line together in said inner cavity of said unit of casing with said bottom end of said siphon line being positioned adjacent to said sealed lower end of said unit of casing and said top end of said siphon line extending through said upper end of said unit of casing;
• and
• sealing said upper end of said unit of casing to prevent compressed natural gas from leaking therethrough.