http://www.ck12.org Chapter 3. Making A Difference
For a time, I thought that the way to solve the long-distance-transport problem was to revert to the way it was done
before planes: ocean liners. Then I looked at the numbers. The sad truth is that ocean liners use more energy
per passenger-km than jumbo jets. The QE2 uses four times as much energy per passenger-km as a jumbo. OK,
it’s a luxury vessel; can we do better with slower tourist-class liners? From 1952 to 1968, the economical way to
cross the Atlantic was in two Dutch-built liners known as “The Economy Twins,” the Maasdam and the Rijnsdam.
These travelled at 16.5 knots (30.5 km/h), so the crossing from Britain to New York took eight days. Their energy
consumption, if they carried a full load of 893 passengers, was 103 kWh per 100 p-km. At a typical 85% occupancy,
the energy consumption was 121 kWh per 100 pkm – more than twice that of the jumbo jet. To be fair to the boats,
they are not only providing transportation: they also provide the passengers and crew with hot air, hot water, light,
and entertainment for several days; but the energy saved back home from being cooped up on the boat is dwarfed by
the boat’s energy consumption, which, in the case of the QE2, is about 3000 kWh per day per passenger.
Figure 20.31:NS Savannah, the first commercial nuclear-powered cargo vessel, passing under the Golden Gate
Bridge in 1962.
So, sadly, I don’t think boats are going to beat planes in energy consumption. If eventually we want a way of
travelling large distances without fossil fuels, perhaps nuclear-powered ships are an interesting option (figures 20.31
& 20.32).