COLUMN | The fuel tank design dilemma [Grey Power]
Some of my best friends design ships for a living, but in their quest to devise dramatic solutions to the problems of decarbonising the shipping industry, I sometimes wonder if they might be going a bit over the top.
I was looking recently at a couple of designs for big bulkers that will be so much greener than their predecessors on account of the LNG with which they will fuel their engines. Admittedly, LNG is not perhaps as green as some would like, being still a fossil fuel, but the intentions surely are honourable. The immediate question, however, is about where the fuel tanks necessary for a long deep-sea voyage are to be situated.
You might think that the obvious solution would be to dedicate a large, heavily insulated space below decks, in the same way that some of the LNG-fueled container ships have been arranged. That may well have been considered, but rejected in favour of a far cheaper option of placing the fuel tanks on deck. Unlike tankers, where the tanks can easily be situated above the cargo tanks, this would not be an option for a bulker, unless one is willing to sacrifice valuable cargo space. So in one design, the LNG tank will straddle the poop abaft the island, while on the other, there are two huge cylindrical tanks, one on each side of the accommodation in which some 20 crew will live.
“With the use of LNG becoming widespread as a marine fuel, a lot of people who have never handled the stuff are going to find themselves involved with it.”
I don’t suppose for a minute that anyone thought about asking seafarers of wit and experience what they thought about living between these enormous tanks of volatile fuel for months on end, their view of the horizon thus obscured on either side. It was cheap and convenient and that was an end to it. We are rather more blasé about LNG than we were once, not least because it has been transported for about half a century in pretty near perfect safety by some of the best professionals ever to take ships to sea.
When the revolutionary idea of taking LNG to sea was in its infancy, there was no end of anxious foreboding about the notion. I can recall passing Methane Progress or her sister alongside her terminal at Canvey Island in the 60s and all hands being told to extinguish their cigarettes. Such was the fear of an explosion from the ship half a mile away.
I even have an account of a planning exercise in which it was assumed that a huge plume of explosive gas drifted over a city after an uncontrolled release, prompting mass evacuation. It never happened, but I suppose it was wise to consider such an emergency and I’m sure that local authorities with gas terminals on their patch have such plans carefully filed away.
Up to now it has been the realm of the cryogenic specialist sector, but with the use of LNG becoming widespread as a marine fuel, a lot of people who have never handled the stuff are going to find themselves involved with it. You have to hope that the regulatory and training regimes for bunkering and on-board handling are robust.
“I suppose some clever naval architect has considered all the things that can go wrong with all the new and exciting fuels we will see in the next few years.”
And it is not just the use of LNG as fuel that is attracting radical designers.
I was reading about a series of ships that have been constructed to carry containerised LNG in deck stowage racks and that seems quite a development. You have to hope that the dockers take good care to ensure the locks are all engaged when they lift them on and off the ship, being aware of the occasional dropped box in some hard-pressed terminals.
But I shouldn’t be such a pessimist, although I was brought up by miserable senior officers who taught you that if something could go wrong, it probably would. And as for those huge tanks on either side of the accommodation, my mind went back to my first car, which was a 1931 Austin 7 and which had a fuel tank under the bonnet sat across the knees of the front seat occupants. There was no fuel gauge, so you used a length of bamboo as a sort of dipstick.
I have to say I was always a bit apprehensive filling the thing, especially when the engine was hot. Once I overflowed the tank and the petrol ran into the dashboard and onto my girlfriend’s knees; fortunately, there were no electrics to cause a spark. I saw one of those little cars for sale the other day for about £20,000, but I sold mine for £17. 50, and bought a suit with the proceeds. That’s sufficient motoring, but you will get my drift.
I suppose some clever naval architect has considered all the things that can go wrong with all the new and exciting fuels we will see in the next few years as the great decarbonisation rolls on. Enormous batteries too might give regulators some cause for concern about fire safety. And although they never ask seafarers their opinion about these matters, it might be prudent to get some opinions from professional salvors, who know from experience that, more often than we like to admit, ships collide, catch fire and possibly even sink.
Maritime industry legend, and former long-term editor of Lloyds List, Michael Grey kicks off each month with topical issues affecting the maritime world at large.