top of page

A nuclear sub with a recycling bin

Last week I wrote about the ongoing growth in global coal demand even as a number of governments attempt to start down the path of decarbonisation. I was thinking further about it over the week, in particular the relationship between ships and their cargoes.

Consider a modern Capesize bulk carrier. It may have a number of hydrodynamic and aerodynamic forms to help it sail more efficiently – a bulbous bow, low-friction paint on the hull, possibly Mewis ducts, a variable pitch propeller or a propeller boss. It may have aerodynamic topsides including bridge wings and a swept accommodation block. We might go further in new designs, with Flettner rotors or rigid sails on the deck, or solar panels on every available upward facing surface. Waste heat recovery systems are in operation to generate electricity to run the ship’s equipment, boilers, light, heat and kettle, at least when the engine load is great enough to run the turbines.

Inside the ship, the Engine Efficiency Design Index has been forcing engineers to be creative in reducing the energy the ship needs to propel itself. An electronically controlled engine burns VLSFO more efficiently than any previous engine design, and a scrubber may sit in the funnel so that old-recipe HFO can be burnt.

The next generation of bulk carriers will have dual-fuel LNG / fuel oil engines designed to meet miners' decarbonisation and clean-air policies. Last July, BHP issued the world’s first tender for LNG-fuelled bulkers to transport up to 27 Mn T of its iron ore. Rashpal Bhatti, Vice President, Maritime and Supply Chain Excellence recognised that “we have a stewardship role, working with our customers, suppliers and others to influence emissions reductions across the full life cycle of our products.”

There are those who say that LNG is not a long-term option, that its well-head to wake CO2 emissions are greater than fuel oil, but LNG does score better on sulphur and nitrogen emissions, which is why BHP said that “LNG may not be the sustainable homogenous fuel of choice for a zero carbon future, we are not prepared to wait for a 100% compliant solution if we know that, together with our partners, we can make significant progress now.”

Moreover, our next generation Capesize will be a fully-connected ship. Voyage optimisation software will compare its performance with other ships in the fleet, as the entire fleet’s AI learns the best way to operate in different seasons, weather conditions and sea states.

Better-quality engineering will reduce maintenance requirements and failure probabilities for moving parts, with spare parts being ordered on a just-in-time basis or even 3-D printed on the ship itself as required. The next generation of satellite communication with the ship and radar on the ship may allow for semi-automation, making port operations more efficient – like your self-parking car of today. Fleet optimisation software will reduce port-line ups and waiting days, reducing the overall demand for ships by increasing the capacity utilisation of the entire fleet. Chronic and significant oversupply could become a thing of the past as a fleet of ultra-efficient bulk carriers is built by fully-automated shipyards with just-in-time delivery.

The generation of smaller bulk carriers after that will be fitted with the first prototype hydrogen engines and with batteries, while ammonia-powered ships, already in the prototype state could be viable for long-haul business if the ammonia is being produced by a low-energy process.

This isn’t the stuff of science fiction, it’s the ships being built by 2030, probably in China under its Made in China 2025 attempt to introduce the best hi-tech and AI solutions to a shipping industry that will be even more dependent on China by then, as the Belt and Road Initiative stretches like a net even further around the globe.

But all of these efforts to turn the dirty old bulk carrier into a gleaming technological guardian of the seas will be pointless, because it and its sisters will still be shipping billions of tonnes of coal around the world to be burned to generate heat and light. The irony of a carbon-neutral ship carrying 180,000 Tonnes of coal repeatedly startles me.

If by some alchemy, some cold-fusion or quantum-energy transformative technology, the global economy can quickly decarbonise and stop burning coal, demand for the bulk carrier will shrink rapidly: coal provides about one third of all bulk carrier demand.

Alternatively, as the effects of climate change become more visible, expensive and politically disruptive, the political pressure to reduce coal use may get stronger. China and India may learn to switch off the lights when they leave the room, like the British did during miners’ strikes in the 1970s, or turn down our heating and wear more wool, like Jimmy Carter implored Americans to do during the second oil price shock.

More probably, investment in renewables will accelerate; the big coal-consuming countries could reach peak coal sooner than current models expect. Demand for seaborne coal could easily peak and go into reverse within the lifetime of ships on the water today.


Carrying 180,000 tonnes of coal on a carbon-neutral Capesize bulker is as cognitively dissonant as a nuclear attack submarine having an environmental policy and a recycling bin. Global coal shipments are in excess of one billion tonnes a year. Decarbonising the 18,000 or so bulk carriers of around 850 Mn Dwt that ship the coal (and all the other dry bulk commodities) is commendable but ultimately futile if the world can’t wean itself off coal in the first place. The greenhouse gasses emitted by ships are a small proportion of those emitted by burning coal. And if we do stop burning the coal, we won’t need all those bulk carriers anyway. No wonder the bulk carrier orderbook has been shrinking. There’s just no evidence that the world needs many more bulk carriers of today’s designs.

233 views0 comments

Recent Posts

See All

Lick it, or become like China

Coronavirus cases continue to mount world-wide. It’s getting to the point now where we all know somebody with symptoms and nearly everyone knows a family that has lost somebody to Covid-19. My family

The End of the Line for Small State Systems?

Last week we reported some Chinese state statistics that detailed the impact of Covid-19 on the economy in January and February, for which most statistics are combined to cover the Lunar New Year. To

bottom of page