Bigger ships, less greenhouse gases
Saturday, 11 February 2012 | 00:00
Antipater of Sidon, a Greek poet, would be writing travel guides had he lived now.Back around 140 BC, he composed a list of the world's main theamata — literally, things to be seen — from the great Pyramid of Giza to the Colossus of Rhodes, a giant bronze statue of the Sun god Titan Helios that stood beside the island's harbour. Today, we know his list as the Seven Wonders of the Ancient World.
Lots of other people have composed similar lists. The American Society of Civil Engineers, for example, has the Empire State Building, the Channel Tunnel and the Golden Gate Bridge among its seven modern wonders. The Panama Canal is also on the society's list.
And who could argue against it? Both the effort that went into its construction and the effect it has had on the world were Homeric. Its expansion, due for completion in just three years, is similarly Herculean. And among the project's benefits will be a substantial reduction in greenhouse gas emissions that even the Oracle at Delphi might not have foreseen.
Spanish explorers first dragged ships the 50 miles across the Isthmus in 1514 and Charles V, the King of Spain, proposed a canal in 1526 to help him get his plundered Peruvian gold home more quickly. The Scots, Americans and French tried various schemes to cross the neck of land over the years, including a railway to supply the California gold rush, but it was only in 1914 that the US government finally succeeded in opening a passage for ships.
The Panama Canal has two lanes leading up from the oceans, with locks raising ships the 26 metres to man-made Gatun Lake, and saves 12,600 km on a trip from New York to San Francisco. More than 200 million cubic metres of earth and rock were excavated, 25 times as much as for the Channel Tunnel. The cost in terms of cash was US$375 million; of the 75,000 workers on the project, 5,600 died from disease and accidents.
It is the locks that determine the maximum size of today's container ships and cruise liners. The Panamax standard is for a beam (width) of not more than 32.2m while the length must be under 289.6m.
Some ships, notably most aircraft carriers, oil supertankers and many bulk ore carriers, are too large for the Canal. The rest are designed to be small enough to fit. Even though most of them will never actually use the Canal — it accounts for less than three per cent of global shipping — much of their value lies in the fact that they could if they needed too.
The Canal's US$25-billion ($2.1-trillion) expansion, which will add an additional, wider lane to the two that already exist, will lead, over time, to replacement of these vessels with bigger ships. And that, says a new paper in the latest issue of the International Journal of Maritime Engineering, will mean more efficiency.
The ships will be able to carry 13,000 containers, instead of the 5,000 that will fit on a Panamax ship at present.
Paul Stott, a naval architect and senior lecturer at Newcastle University's School of Marine Science and Technology, calculated that the new, bigger ships will require 16 per cent less fuel per tonne of cargo than existing vessels.
Since shipping is expected to make up 12 to 18 per cent of the world's CO2 output by 2050, and half of the world's larger vessels could be replaced, the potential savings could make a measurable difference.
"The size of the benefit is much larger than one might think, based solely on the canal's traffic statistics," said Stott. It has to be viewed in the context of the whole fleet."
The last decade saw a boom in shipbuilding, followed by a collapse in demand due to the world recession. As a result, freight rates are currently low, so a 16 per cent saving on fuel costs could make new, larger ships more attractive.
Source: Jamaica Observer