Kpler tracks NGLs cargoes based on volumes carried and transported aboard vessels. Because NGLs products are shipped at very low temperatures but are often reported commercially at a standard reference temperature, volume differences naturally arise between these two measurement conditions.

To ensure consistency and comparability across the supply chain, Kpler applies a product-specific expansion ratio (also known as a thermal expansion coefficient) when converting between refrigerated vessel volumes and standard reference volumes.

NGLs products expand and contract depending on temperature & pressure.

During transportation, products such as propane, butane and ethane are often carried in a refrigerated state. However, commercial documentation and industry reporting often express quantities at a standard reference temperature of 60°F (15.6°C).

As a result, the same cargo may be represented by different volume figures depending on the measurement basis used.

For example:

Applying an expansion ratio ensures that volumes can be compared consistently across these different reporting standards.

Kpler maintains an expansion ratio for each applicable NGL product. The ratio is used to convert:

Refrigerated vessel volume → Standard reference volume (60°F)

This allows users to compare vessel-based estimates with market documentation that reports volumes at standard conditions.

Kpler's vessel-derived cargo estimates are primarily calculated using:

These estimates reflect cargo volumes under transportation conditions.

When users compare Kpler volumes with documentation reported at standard reference conditions, a volumetric adjustment may be required to ensure both datasets are expressed on the same temperature basis.

Bills of Lading for NGL cargoes commonly report volumes at 60°F.

Because vessel-based estimates and BOL figures expressed under different temperature assumptions, differences can occur even when both sources describe the same cargo.

When benchmarking Kpler data against BOLs or terminal-reported figures, users should take the applicable product expansion ratio into account to ensure a like-for-like comparison.

The expansion ratio is assigned at the product level and is not recalculated dynamically for individual cargo temperatures.

This approach provides a consistent and transparent methodology across all NGLs trades and regions.

If a volume is already reported at 60°F (for example, a BOL volume), no further temperature adjustment should be applied.

Applying the adjustment twice would distort the underlying quantity.

Kpler continuously reviews its methodologies to ensure the highest possible level of accuracy, consistency and alignment with industry reporting practices.

The application of product-specific expansion ratios helps bridge differences between refrigerated transportation volumes and standardized commercial reporting, enabling more reliable comparisons across datasets and providing greater transparency for NGLs market participants.