There are clear signs that as a result of rising oil prices, changes in taxation affecting fuels and corporate responsibility, newer ships are becoming 'cleaner' and many solutions are being developed to help address the environmental impact.
Lowering the speed of travel may be one way of reducing emissions, just as slowing down improves the mileage on your truck or car, but this seems to go against the trend of consumer demand for ever quicker logistics. Sails on ships have been trialled but these are not really feasible on short sea ferry movements. Mechanical sails, looking much like a huge vertical spinning cylinder that sits on deck, have also been developed and may offer a way to help reduce fuel consumption. Another option is the use of scrubbers to clean the emissions that fossil fuel produces.
The building of ships that use Liquefied Natural Gas (LNG) is another way to help towards the reduction in pollution but it is still a fossil fuel so has an environmental impact and is not sustainable. Electric propulsion is also being researched although it is less efficient and more expensive overall due to high installation costs.
Stena AB are also working on their Air Max technology. The air lubrication system works on the simple principle of trapping a layer of air bubbles beneath the ship’s hull. A dedicated system is used to generate tiny bubbles which then pass continuously beneath the ship’s surface, providing a layer of air on which the ship rides, reducing drag. Air lubrication could save around 12% of fuel consumption. That’s a substantial amount when you think how much fuel that could save for huge ships and ferries.
It seems no single fix or silver bullet can resolve the problem of pollution completely, but everything that is being done is making a contribution.