The global appetite for natural gas is climbing. Natural gas – mostly methane – now accounts for a record share of primary energy (around 24–25% globally). It is relatively clean-burning compared to coal or oil, and it can back up intermittent renewables (e.g. gas-fired generators filled gaps when solar/wind output dipped). However, gas is often found far from end users or transmission pipelines. In these cases liquefied natural gas (LNG) – natural gas cooled to –162 °C to condense it – is used to transport fuel by tanker. Liquefaction shrinks gas volume by ~600×, making long-distance or off-grid delivery possible. Traditionally, LNG plants have been huge (millions of tonnes per year) to capture economies of scale. But in the past decade, small-scale LNG – compact liquefiers that produce well under a million tonnes per year – have become an attractive alternative for many niche markets.
Small-scale LNG plants bring the benefits of liquefaction to gas sources that cannot justify a mega-plant or a pipeline. They enable companies to monetize small or remote gas fields, flare gas from oil wells, or serve “LNG islands” (customers beyond the grid). In contrast, large-scale LNG plants are tied to major transmission systems and always export large volumes by sea. Understanding the differences and applications of small- versus large-scale LNG is crucial for planning new projects and meeting modern energy needs.