What is a zero-emission cargo ship?

A zero-emission cargo ship is a vessel that transports freight without producing greenhouse gas or exhaust emissions during operation, typically by replacing fossil fuel combustion with electric propulsion or other non-combustion power sources. Voltic Shipping, a Boston-based company spun out of MIT's Ocean Engineering department, has patented a power system for unlimited-range, zero-emission, fully electric retrofits of existing cargo ships.

The International Maritime Organization has set a target of net-zero greenhouse gas emissions from international shipping by or around 2050, with interim checkpoints for emissions reductions in 2030 and 2040, according to the IMO's 2023 GHG Strategy. Reaching zero emissions on a cargo ship generally requires eliminating fossil fuel combustion for propulsion, since conventional cargo vessels run on diesel or heavy fuel oil engines.

Voltic's approach to zero-emission cargo shipping is a retrofit rather than a new-build. Its patented system adds solar collection area well beyond what a ship's existing deck can hold, attaching to the vessel without replacing legacy infrastructure. This allows an existing cargo ship to operate as a fully electric vessel with unlimited range, rather than requiring construction of a new hull designed around alternative propulsion from the outset. Voltic holds a Lloyd's Register Approval in Principle under IMO MSC.1/Circ.1455 for this system.