AET Insights


Ship-to-Ship (STS) transfer operations are an integral part of the global energy supply chain.  This highly complex procedure (also known as ‘lightering’), enables tankers to offload their cargoes in smaller parcels whilst at anchor or underway offshore, without having to berth at a port.

Lightering provides operators with far greater flexibility to call at ports and terminals with draught or vessel size restrictions. It reduces berthing charges and enhances the overall efficiency of moving petroleum, gas and chemical cargoes worldwide. The vast majority of STS operations take place around major energy hubs across the U.S. Gulf, North Sea and more recently, Brazil, where AET has been providing STS transfers since 2013.

Whilst STS operations may sound routine, they are highly complex and skilled operations, and should be performed with specialist vessels and equipment, manned with highly trained crew and supported by attentive and dedicated teams ashore. Given the often challenging environmental and operating conditions offshore and the precision with which STS operations must be conducted, there is no room for oversight or error. AET built purpose-specific LSVs equipped with the latest technology to operate in the US Gulf of Mexico and partners with other high-quality providers to ensure all LSVs are operated by highly trained specialist crew and support teams.

For 24  years, AET has been a leading provider of STS transfer services, having completed more than 13,000 transfers to date. Just last year alone, AET safely carried out more than 800 STS transfers (which is more than 300 million barrels), primarily along the U.S Gulf and Atlantic Coast, Uruguay, and Brazil. Due to our vigilant operations, we also hold an excellent safety record.

This is testament to the efforts of our entire team; at sea and ashore. While vessel technology enables us to provide STS transfers, it is our people at AET, and our shipmanagement colleagues at Eaglestar – their knowledge, experience and commitment to safety and compliance – that make sure operations are successful.