Natural gas consumption in the United States was measured at roughly 24.3 trillion cubic feet (Tcf) in 2011, yet as shale plays in the country have expanded, so too has natural gas production. This has resulted in a glut of natural gas in the U.S. and Canada, increasing the desire to export it to other countries. This requires special infrastructure, though: the natural gas must be converted to a liquid to reduce space requirements and make it economical to transport and store. That’s where liquefied natural gas (LNG) facilities and vessels come in.

However, cost is a major concern for the development and construction of traditional LNG production and distribution infrastructure. The liquefaction plant itself — found in shipping terminals and used to convert natural gas into LNG — represents nearly 50 percent of a terminal’s total cost (PDF), more in locations like Australia where construction costs are higher. Equipment represents roughly 30 percent of total cost and includes refrigeration compressors and drivers as well as LNG storage tanks. The stainless steel piping and equipment used to more efficiently handle LNG at cryogenic temperatures also increases costs.

LNG carriers make up another vital component of the transportation network, and they too are not cheap. Averaging at around $200 million apiece, 394 vessels made up the global fleet in mid-2014, with enough demand to increase that number by 225 by the end of 2020. While styles vary and improve with technological advances, the general idea remains the same: several tanks, skirts, and pumps contain the LNG at pressure while insulation helps control boil off of the LNG. Receiving ports will then have the cargo pumped ashore using cargo pumps either to an onshore storage facility or a feed to a regasification plant. Storage tanks fully contain the LNG above or below ground, depending on the design. They maintain the LNG under a constant pressure, releasing boil-off gas from the tank which acts as auto-refrigeration.

As for the future outlook of LNG transportation and storage, offshore storage of LNG may become a consideration, using more traditional self-supporting tanks for their ability to better handle sloshing. Another future trend is the shrinking of LNG midstream infrastructure down to a smaller scale, bringing about shorter LNG transportation chains and making the product more available at smaller economies of scale.