The Silent Revolution: How Old-School Efficiency Upgrades Are Outpacing Flashy Green Tech

Data, Ducts, and Diesel Savings

While headlines chase hydrogen hype and ammonia promises, shipping’s quiet efficiency revolution is delivering staggering results. Höegh Autoliners slashed emissions by 58% per vehicle on its Aurora-class carriers—without a drop of alternative fuel. The secret? Relentless optimization. Odfjell’s 53% CO2 cut across 70 vessels since 2008 proves this isn’t a fluke: 140 retrofits, from propeller boss caps to AI-driven weather routing, turned tankers into climate warriors. “Everyone’s obsessed with fuels, but efficiency is the cheat code,” says an Odfjell engineer.

Weather routing tech transformed our average sea state from 3.5m waves in 2008 to just 0.6m—that’s the difference between a rollercoaster and a river cruise for fuel burn.

Low-Tech Wins, High-Tech Flops

Odfjell’s 22m suction sails on the Bow Olympus tanker outperformed models, while hull cleaning saved 3.5 tons of daily fuel per ship. Even LED lights became unsung heroes, with annual savings of 40–100 tons per vessel. Retrofits like Mewis ducts pay back in two years, but not all tech passed muster. Air lubrication systems and solid oxide fuel cells (SOFCs) failed field tests, proving that simplicity often wins. With 63% of global ships still lacking basic energy-saving kits, the low-hanging fruit is rotting on the vine.

The 80% Problem

Here’s why efficiency trumps e-fuels: renewable energy loses 80% before reaching a ship’s propeller. Hydrogen production wastes 30%, ammonia conversion another 30%, and ship engines burn 50–60% of what remains. Compare that to wind-assisted propulsion’s 10% loss, and the math gets brutal. “We’re pouring clean energy into a leaky bucket,” admits an Odfjell strategist. Their new 57% emissions target leans harder on retrofits—because until the energy equation changes, the most sustainable fuel is the fuel you don’t use.