Voyaging into the Future Rolls-Royce Style

Oskar Levander, VP of innovation, engineering and technology at Rolls-Royce talks about the challenges and opportunities for the marine world:

Ship efficiency is the principal driver for the future as it directly impacts operating costs. There are many ways to improve it – change the vessel’s design to do its job more effectively, improve the hullform and systems to reduce fuel burn, and by optimising the transport chain of which the vessel is a part. All these factors must be evaluated together, avoiding silos of thinking to get the best results.

Fuel transition

The era of cheap energy seems to be over; we are at the dawn of the fuel transition era. Today almost all marine fuel is oil based. In the future, there will be three or more choices. Heavy fuel oil (HFO) will not disappear, and low sulphur distillates will gain acceptance. Alternatives such as dimethyl ether (DME), methanol and other biofuels will probably play a smaller part. Fuel choice is driven by cost, and increasingly by emissions regulations. These rules mean there is no alternative but to move to greener fuels or fit abatement systems.

Emission control areas have been introduced to limit NOx and SOx in Europe and the U.S.
Legislation, plus incentives like Norway’s NOx emissions tax and subsidy, are cutting pollution levels. Now attention is turning to the gases which contribute to climate change, first is CO2. Reducing CO2 emissions is not so easy, and I have been convinced for a long time that LNG will be the fuel of the future for most ships. Natural gas is available worldwide and when used in a gas engine, CO2 reduction is sizeable, at over 20 per cent. It also supports human health concerns as particulates are negligible.

LNG as a marine fuel has begun to take off, but so far is restricted by lack of bunkering.
The engines and systems to burn the fuel are available, proven and simple to use. The transition looks like it will be similar to the change from sail to coal, which was first used on routes where coal was already available, before expanding worldwide.

Choosing a fuel is one thing, but improving ship efficiency to use less is another. Times are changing, with statutory measures such as Energy Efficiency Design Index (EEDI) coming in. I approve of the idea of encouraging more efficient ships with a design index, but I am sceptical about the formulations used in EEDI. It is penalising installed power and thereby ship speed, not focusing on the actual efficiency of the design in real conditions. There is no doubt fuel efficiency will remain prominent, with plenty of new ideas and new twists on old ones.

Propulsion systems

Rolls-Royce already has successful references for hybrid propulsion in various configurations combining mechanical and electric drive to get the lowest fuel burn in different operating modes. The use of permanent magnet motors also offers an increase in operating efficiency. The future will see other types of hybrid adding to this. Already with us, and discussed on page 12, are hybrids combining engine power with energy storage. Harbour tugs, due to their operating profile are ideal candidates for gas engines plus battery hybrid propulsion, as are many coastal and short sea vessels, MS Høydal being a good example.

Another approach is to harness solar, wave and wind energy. Solar cells are used in pleasure boats and small commercial craft, but the output is low. The question is whether solar panels can contribute to more than a ‘green feel-good factor’ for larger vessels.

Wind energy on the other hand can have a more positive impact, although I’m not suggesting a return to the days of clipper ships. Calculations show that even with today’s shipping routes and service speeds, auxiliary wind power could cut fuel use by five to 30 per cent and possibly more.

But there are constraints. Masts and sails must not get in the way of cargo handling and they should be simple to operate. It will be a significant challenge for soft sails to meet these criteria, but some types of hard sail may, as could Flettner rotors that have the advantage of simple control and no manual intervention.

Thinking the unthinkable

Sometimes what was unthinkable yesterday is tomorrow’s reality. So now it is time to consider a roadmap to unmanned vessels of various types. Steps have already been taken, mainly in the naval area. On the way, certain functions will be moved ashore. Engine/equipment monitoring and some underwater operations in the offshore sector could be the first. A growing number of vessels are already equipped with cameras that can see at night and through fog and snow, and have systems to transmit large volumes of data. Given that the technology is in place, is now the time to move some operations ashore? Is it better to have a crew of 20 sailing in a gale in the North Sea, or say five in a control room on shore?

When ‘fleet optimisation’ is considered, the advantages compound. The same person can monitor and steer many ships. As conditions ashore are often preferred, it will also help retain qualified and competent crew, and is safer.

Many facilities and systems on board are only there to ensure that the crew is kept fed, safe, and comfortable. Eliminate or reduce the need for people, and vessels could be radically simplified. Attitudes and ways of working will need to change, but safe operation is possible, particularly for vessels running between two or three fixed points.

Shipping’s approach is usually about complying to regulations in the most cost efficient way while addressing the key cost issues of fuel, finance, cargo handling and crew. They can all be influenced by holistic ship design. In the future, we must not think of a ship as a number of separate processes or systems, but as a whole where all aspects affect the other. Only by thinking the unthinkable can we truly affect costs.