Orkney International Science Festival 2023

By Eamonn Keyes

A New Day for the Ferryman?

Phoenix Cinema, Pickaquoy, Kirkwall

Given the political football that ferry replacement has become, along with the need to move towards Net Zero and re-examine energy requirements, it is timely to look at what the future might hold in term of ferry replacement for Orkney or alternative means of moving from the Scottish mainland to Orkney and within Orkney itself.

Orkney’s ferries are ageing and fuel-prodigal – but what can replace them? Could it be new energy-efficient ships, or bridges or tunnels or causeways – or a mix of all the various options?

Roy Pedersen, former head of transport for HIE and the original architect of the Road Equivalent Tariff (RET) scheme, joined Professor Alf Baird to set out the options. Prof. Baird is a former Professor of Maritime Business and Director of the Maritime Transport Research Group at Edinburgh Napier University. He also has a PhD in Strategic Management in Global Shipping.

The talk came in two parts, the first delivered by Professor Alf Baird looking at design options and examining the best value for ferry replacements.

Firstly, Professor Alf Baird spoke about ferry design, and gave a detailed comparison between monohull ferries and catamarans, taking in their efficiency, energy usage, building and operating costs, CO2 emissions, reliability and safety.

In every area it seems that catamarans are far superior, generally being twice as efficient and requiring less than half the fuel of the current Government favoured comparable monohull ferries, with only half the emissions. In addition, they cost around one third the price and operating costs are about half those of a monohull design.

The controversial Glen Sannox was originally scheduled to cost £50 million, which has now risen steeply to £150 million, whereas the Alfred, comparable in passenger and car capacity, cost £14.5 million. The point was made that Calmac could have replaced its entire fleet for that cost with catamarans, increasing capacity at the same time.

Prof. Baird then spent some time dealing with the arguments brought up against using catamaran designs and proceeded to demolish them one by one.

These included ferry reliability (comparison table shown below), safety, fulfilling regulations, using piers and many other issues.

Catamarans are more stable, are better at seakeeping, can carry much more cargo than monohulls and with their double hulls are 82% safer because of the double hulls, which also allow foam buoyancy to be added in areas fore, aft and under the car decks for additional safety.

The conclusion was that greatest value and better services would be obtained by making all replacement ferries catamarans, a choice which so far has been hindered by a lack of innovatory thinking in government.

The second part of the talk was presented by Roy Pedersen, looking at how the need to conserve energy and reduce emissions would impact on the choice of fuel possibilities for future ferries.

Roy Pedersen gave a history of the use of ferries to and within Orkney to date, starting with a 1960s Scottish Office declaration that there was ‘little demand for ferries for the North Isles travel and little potential for tourism’. The were no Roll On, Roll Off (RORO) ferries planned, with the emphasis being on Lift On, Lift Off (LOLO) ferries.

As a result ferry routes and times were scheduled around freight with little thought for passengers, and it was only with the coming of Pentland Ferries that it became possible to travel to the Scottish mainland and back within the same day.

The Norwegian MRF Report in 1963 set the standard for future systems with its findings.

These stated that the ferries should be part of the road system, the shortest most frequent crossings should be used, ships should be simple with minimal crewing, crews should live ashore, and terminals should have lock on linkspans, by which passengers should land and board.

With the advent of the Pentalina tourists began to take advantage of the service, leading to Orkney becoming a popular destination. Roy Pedersen then talked about the comparison between the Pentland services using the graphic below.

The differences in efficiency and costs between the two ferries are very clear from this graphic, and definitely support the rationale supported by both contributors.

Roy then gave us a tour of the available and upcoming new technologies.

This began with an electric Icelandic ferry, the Herjolfur, which can also utilise diesel.

Under favourable conditions the ship runs on electricity alone but can use up to 2.5 tons of diesel per weeks, as opposed to the 35 tons it would normally require. It is also silent!

Scotland has smaller hybrid electro-diesel ferries, such as the Lochinvar, but which then use more diesel than a pure diesel ferry such as the Sound of Seil, purely because of the huge weight of the battery.

New proposed designs are trying to maximise the use of renewable technologies in the move to Net Zero, and again, the Scandinavians are to the fore. These include real innovation (shown below), for example the Norwegian model which will use batteries, sail and solar panels together. When the wind blows three retractable sails will emerge from the decks to take advantage of it, and they will be covered in solar panels, which will recharge the batteries. This could be in operation within seven years.

Sails are already in use with some Norwegian freight carriers. Norway is unlikely to pursue battery power in the future, due to the means of their product, weight and life, and there is talk of them even banning electrical cars on board ferries because of the problem of runaway fires in electric car batteries, which can be very hard to extinguish.

Green hydrogen is one of the leading possibilities for future powering but requires cheap power for electrolysis in quantity to be commercially viable. The tidal stream of Pentland Firth could enable this if added to wind power to ensure adequate base load. Another contender is the Aquarius hydrogen fuel cell under development in Israel.

The world’s first hydrogen powered ferry has now gone into service, not surprising that it is again in Norway.  Carrying 300 passengers, 80 cars and 10 cargo trailers, the Norled Hydra design would seem ideal for use in Orkney. This can reduce carbon emissions up to 95%.

Once hydrogen is shown to be successful as a fuel it is almost inevitable that it will become adapted for use with aircraft, so the future for Orkney could well be hydrogen powered ferries sailing our waters with hydrogen powered aircraft overhead, all hugely reducing our emissions, becoming an efficient and effective way of providing an enhanced and more effective service for Orkney and Shetland.

Slides and images provided by Prof Alf Baird, Roy Pedersen, Mike Robertson and Eamonn Keyes.