LNG FAQ
Answers to the most frequently asked questions about liquefied natural gas (LNG) — production, storage, transportation, safety, costs, and industrial applications.
Frequently Asked Questions About LNG
Liquefied natural gas is a technology that many energy professionals encounter but few fully understand. These questions and answers address the fundamentals of LNG — what it is, how it works, what it costs, and how it is safely handled — to provide a practical knowledge foundation for industrial operators, energy professionals, and investors.
For a deeper understanding of LNG basics, see our comprehensive guide: What Is LNG and How Does It Work?
Production and Technology Questions
See the FAQ section below for detailed answers to all common LNG questions, organized by topic area.
What does LNG stand for?
LNG stands for Liquefied Natural Gas. It is natural gas (primarily methane) that has been cooled to approximately -260°F (-162°C), converting it from a gas to a liquid. In liquid form, LNG occupies about 1/600th of the volume of the equivalent amount of natural gas.
How is LNG different from propane (LPG)?
LNG is liquefied methane, stored at cryogenic temperatures (-260°F) at atmospheric pressure. LPG (liquefied petroleum gas, which includes propane and butane) is stored as a liquid at much higher temperatures (-44°F for propane) by applying moderate pressure. They are different molecules with different properties, applications, and infrastructure requirements.
Is LNG explosive?
LNG itself is not explosive. Natural gas is flammable only within a specific concentration range in air (5–15%). Outside this range, it will neither ignite nor explode. Additionally, natural gas is lighter than air, so it disperses upward rather than accumulating in low areas. LNG has an excellent safety record compared to heavier liquid fuels.
How long can LNG be stored?
LNG can be stored for weeks to months in properly insulated cryogenic tanks. All LNG storage systems experience some 'boil-off' — a small percentage that vaporizes over time as heat enters the tank. Well-designed storage systems manage boil-off through pressure relief and tank insulation systems.
What temperature is LNG stored at?
LNG is stored at approximately -260°F (-162°C) at atmospheric pressure. This extreme cryogenic temperature requires specially designed tanks with vacuum insulation systems using materials capable of withstanding cryogenic conditions without becoming brittle.
Can LNG be used in existing natural gas equipment?
Yes. When LNG is regasified (converted back to gas), it is chemically identical to pipeline natural gas and can be used in any equipment designed to operate on natural gas — boilers, furnaces, generators, turbines, and process heating equipment.
What is the energy content of LNG?
LNG has approximately 84,000 BTU per gallon in liquid form, and approximately 1,020 BTU per standard cubic foot when regasified as natural gas. One gallon of LNG is roughly equivalent to 6–7 pounds of LNG or approximately 8.5 therms of natural gas.
How is LNG priced?
LNG pricing for industrial and commercial users reflects the cost of the natural gas commodity (typically referenced to Henry Hub prices), plus liquefaction cost, logistics cost, and any applicable margins. Delivered LNG cost varies significantly by location, volume, and supply chain design.
What permits are required for on-site LNG storage?
LNG storage at industrial facilities in the United States is governed by NFPA 59A (Standard for the Production, Storage, and Handling of Liquefied Natural Gas). Local fire codes, zoning, and state environmental permits also apply. Requirements vary by jurisdiction and facility scale.
How far in advance should LNG deliveries be scheduled?
Most LNG logistics providers recommend scheduling deliveries 24–72 hours in advance for standard routes, though schedule flexibility varies by provider and region. Well-managed LNG supply systems include tank telemetry that allows the logistics provider to proactively schedule deliveries based on actual consumption, reducing the scheduling burden on the customer.
LNG Questions? Talk to Our Team
United Energy's technical team can answer your specific LNG questions and help design the right supply chain for your operation.