A container ship just tested a system to capture its own CO2 emissions

Shipping companies are experimenting with onboard carbon capture systems, but they face difficult trade-offs on energy and space for regular cargo

By James Dinneen
16 February 2024

About 3 per cent of all carbon emissions are due to the shipping industry

A 240-metre-long container ship called the Sounion Trader recently completed a test of an onboard carbon capture system as it cruised around the Persian Gulf. It is one of a small but growing number of ships trying to reduce their climate footprint by capturing and storing their carbon dioxide emissions onboard – but finding space for tonnes of CO2 is a challenge.

“You’re miniaturising a system that was designed for huge power plants,” says Roujia Wen at Seabound, the UK-based start-up behind the Sounion Trader’s test run.

Shipping is responsible for around 3 per cent of global CO2 emissions. To reduce that, shippers are using cleaner fuels, lubricating hulls with bubbles to improve fuel efficiency and even turning back to sails. But near-term options to reach the industry’s pledge of net-zero emissions by 2050 are limited .

Another possibility is capturing ships’ emissions and storing them onboard, but it faces major obstacles. One is supplying the energy to recharge the chemical sorbents used to absorb CO2. Tristan Smith at University College London says some existing systems increase fuel use by a third just to catch half of CO2 emissions.