The 7 truths about Wind propulsion

Truth No 1: Wind energy supply is not constant, but variable in time and place – so what?

Every natural source of energy is periodical - by nature (sic) - and that even, asymmetrical in rhythms.

I haven’t seen any shipowner complaining to the shipyard or to the naval architect, when ordering a new ship and paying tens or even hundreds of million dollars, that the guaranteed speed and fuel consumption mentioned in the NB contract is referring only to calm water conditions and max sea state 2, which is a grand minority percentage of the real operational environment for a ship…

So why wind uncertainty becomes a potential issue for the Investor, while the Sea state uncertainty is not?

The Shipping Industry must accept Wind as a natural phenomenon, as has accepted the Seas, embrace and take it differently into account when making spreadsheet calculations about paybacks or return of Investment decisions. Wind is a powerful form of energy and despite its periodicity it has an aggregate long-term stability in intensity and flow, so it will always be there, available.

Truth No 2: Wind propulsion system providers should consider an Annual, Consistent, Global reach efficiency of their systems

We have heard so far numerous marketing and promotional announcements for how wind propulsion technologies are proven to offer from conservative figures of at least 5%-8% savings, promising and encouraging 10-20% savings or even shocking 40%-100% savings.

While the handful counted global running commercial ship references are 1 x RoRo sailing in specifically limited North Europe/Baltic voyages, 1 x RoPax ship with 1 line Port-to-Port service, 3-4 multipurpose cargo ships with regional coastal services, 1 x VLCC that has done a trial voyage from Middle East to Asia, a supramax bulk carrier and a product tanker that have done together 5-6 typical trade routes between 2 to max 3 adjacent continents, most being Test units (with every associated calibrations and corrections for performance simulations still on-going).

The aggregate operational feedback so far says little about the real efficiency and effectiveness of wind propulsion on ships, while excessive marketing efforts look to me like shooting at own feet. Even if an Owner signs exhaustive NDAs with any system provider, nobody so far has a consistent, annual, global reach show case to demonstrate.

This means ships that have been sailing consistently for at least 1 full year - or more, covering aggregately at least 80% of the dense global trade routes and have been diligently and optimally used during every such voyage wherever the wind conditions allow.

Truth No 3: Wind power is not primarily about fuel savings, but CO2 emission reductions and ship performance optimization

It looks incompatible as a statement, because where there is a power saving from exploiting the winds, there must be a fuel saving, however the more we delve into the pragmatic applicability of the wind propulsion and the more we march towards other forms of energy efficiency technology adaptations irrelevant with the wind, the business model for Investment should be built around CO2 emission reduction, viewing Wind propulsion contributing towards a step closer to a zero emission ship identity and status.

Therefore, when Ship Owners and Operators are trying to view wind propulsion technologies application on ships through a similar lens as they viewed i.e. Scrubbers or Mewis ducts for instance, (i.e. only basis economic payback) the investments will never be encouraged for prompt materialization. There is an obvious fuel saving when wind propulsion is applied on board, and it comes from reducing the power needed for keeping same ship speed, but it cannot be the Prime criteria for structuring an investment plan.

I have had dealt enough during the last 10 years with the ‘payback-burden’ for any modern, advanced, improved technology to be implemented on board and which can provide better quality of equipment, better ship functionality, better operational practices and improved service of transporting goods.

Truth No 4: Technology & Service providers sometimes tempt to have a ‘ship device’ selling mindset

The Rotor comes with a 100 years old invention history, the Turbovoile (Turbosail) of Jean Jacque Cousteau is 40 years old concept, all such come suddenly as a disruptive innovation towards zero emission ships, while some Port captains have laughed at me on the idea that a filthy and smelly Oil tanker deck will be filled with Masts, rigs and soft or rigid sails extending between the Main Manifold.

As a natural consequence, wind propulsion starts to look weird in nature and incompatible with current ocean going commercial and cargo ship benchmarks. In a way - that will be discussed later - it is.

This impression is aggravated when some Makers are promising, figures the likes of 40-100% savings for their technology. Their figures maybe totally Correct, but the questions are: Where, When and How?

This aggressiveness does not help the credibility of the adoption of the technologies, because shipping industry people nowadays are highly educated, highly informed decision makers who have been already bombarded for a decade with % reduction promises and products that were not able to consistently deliver in various other energy saving segments.

Wind technology providers should be more ‘technocratically’ transparent, and try to propose to the ship owner not another fuel saving device but a CO2 emission reduction technology which works periodically on board, which has a medium level of utilization rate on a statistical average consideration, and they should be discussing with the ship owners on how such technologies can improve other important ship performance features, for instance like roll damping, sea keeping and voyage optimization.

Rotors are offering supportive gyroscopic effect assistance to reduce low GM rolling motions in RoRo & PCTC carriers for instance (who are the most vulnerable), while the Propulsion Kite is highly helping the potentially unstable course keeping of the ship due to high swells and currents in tailwinds or quarter tailwinds, or when keeping course and manoeuvring in slow speeds.

Class Societies are putting AIP stamps like a cherry on top of the ‘marketing cake’, but they cannot help otherwise than using the same rules as they use for certifying Cranes to provide such preliminary approvals for novel wind propulsion technologies, and they just now enter the ‘deep seas’ of examining serious aspects such as intact and damage stability, hydrodynamic flow distortions in the propeller & rudder, manoeuvrability, even how to test these new systems during sea trials is totally unknown at the moment.

Any such kind of spasmodic actions do not help the Wind propulsion technology Industry to provide a reliable and mature face in alignment with the expectations of the demanding and highly accountable shipping community.

Truth No 5: Wind propulsion is a Naval Architecture issue, not a Marine engineering issue

When you still use a hull incorporated internal combustion engine which drives mechanically a propeller through a shaft, using the water inflow to steer the ship through a rudder, the efforts currently made to reduce the CO2 emissions from this propulsion train concept is to replace it only with a different ‘machine’ before the tailshaft that uses different fuel and/or a technique that emits much less or none CO2. You do not change the concept of energy transmission from fuel to thrust, and eventually all the rest remains the same: the hull form - pretty much, a propeller is always somewhere there pushing from outside, the ship dimensions, the cargo part, the accommodation part and the motional performance of the ship in seas and waves - all same.

This is a Marine Engineering problem to solve: how to replace fossil fuels with zero-emission fuels for an untouched, similar ship drive main technology.

Wind propulsion is a pure Naval Architecture problem: It all starts with the Wind.

How to build a ship that has specific main dimension limitations due trade restrictions so that she can be able to use the wind most optimally for her particular size and type. It is wrong to approach the wind propulsion as a marine engineering problem. It has of course engineering consequences to be addressed, but those come at a later stage of the ship design development.

Current wind technology providers, thinking of only promising fuel savings (pls see Truth No 3 & 4 above) are mainly opting for the retrofit market: And they are right. The existing ships will desperately need most of their systems implementation so that both CO2 emissions and fuel costs are reduced. However, the adaptation of such technologies even on a retrofit basis, after a certain scale of application, it will become a major naval architecture problem for the existing ships. Install a 6 series of 40x15m Wing Sails, or a similar large series of double rotors on a Capesize Bulk carrier each one after each cargo hold, and the ship will start to develop heel and leeways angles during BF 6-7 quarter wind, for which conditions she has not been initially designed.

Therefore, there will be physical limitations to the extent of applying wind propulsors on existing ships and this will eventually impact promised efficiencies to much less.

The Wind propulsion can disrupt the standard commercial ships naval architecture approach when it comes to Newbuildings: Ship Designers should start with the Wind when they think about their next VLCC or their next Panamax Bulk carrier, and how such exploitation of abundant energy can be maximized through design limitations.

Then, it would all make great sense, and positive surprises will emerge with open minded design thinking.

Truth No 6: There is a Timing for Everything, Wind propulsion included

Ballast water treatment on board has been discussed for implementation since 2004. It was finally adopted fully by 2016 and enforcement starting September 2017. 12 years later from the initial convention adoption, stemming from the righteous decision of the IMO to solve an indisputably large marine ecosystem biological problem.

Scrubbers have been in operation on board ships since 2010, when the first such were installed on DFDS ships - if I recall correctly - to cope with the SECA limits in the Baltics, where they were operating by 100% of their time. Despite of the benefits of the SOx emissions reduction, the relatively proven and conventional style of technology (similar to Inert Gas scrubbing systems on tankers and with 10+ prior applicability in the Industry), and the time availability ship owners had from 2016 when the 0.5%S global cap was adopted until 1/1/2020, by the end of 2017 we had roughly only 500 ships with such systems. From 2018-2020 the figure suddenly exploded to abt 4.000 systems.

So what will define the broad implementation of wind propulsion technologies? What will be the Accelerators of acceptance and adoption of such renewable energy sources of technology exploitation on ships? What is the history telling us on the behavioural economics that tend to apply in such cases on the Industry stakeholders?

The currently market available wind propulsion system providers have - to the large extent of them - very little ‘frictional’ experience with the ‘Roman arena’ of the shipping industry, therefore it is dangerous that they might make Investment and promotional mistakes they are not aware of how this market is truly functioning. While when the market matures enough to have technologically a bullet-proof marine application, why shouldn’t the Big Marine power/energy Giants leave this out of their portfolios? Personally, I expect various acquisitions, when sufficient references are built, and the research/regulatory framework is developed further throughout the years.

While, when it will be revealed that the optimal incorporation of such fragmented on-board propulsion power train requires a high degree of operational Automation, the presence of such Big Players will also enhance safety confidence for commercial stakeholders to adopt (i.e. Insurers, etc).

Truth No 7: Wind propulsion will Disrupt the way Trading routes are established

Wind around the globe is a product of weather formation, air mass circulation, geophysical terrain pressure dynamics, earth movement/positioning and even planetary influence determined, such as solar electromagnetic wave intensity and moon location in time.

Ships with wind propulsors on board cannot sail at the same routes where ships without wind propulsors do sail. Well, they can, but then the latter will be most of the time inactive (so why the fuss?).

When you have medium intensity winds, you have low wave heights, but the ship sails fast, so she has to slow down considerably to take up efficiently wind propulsion. When you have high intensity winds, you have high wave heights. When you have high waves, the ship slows down not only to preserve fuel but also to reduce damages due to bow slamming, propeller racing, roll resonance with wave encounter, parametric rolling, breaching and other unfavourable factors. Thus, when you have high intensity winds through high waves, you cannot speed up to use them as much as abundantly they are available for you.

The only way possible for any ocean going trading ship to exploit the optimal potential of any given wind propulsion technology in any optimal arrangement on board, is to have a 100% dependent functional, smart and automatic voyage optimization software which will take into consideration weather changes, weather forecasting, ship motions, cargo securing, safety of navigation, course keeping, sea keeping, speed and power adjustments of the full propulsion train, passenger comfort, fuel optimization and maintaining ETA, all under total orchestration.

This kind of optimal propulsion combination and operational control on board will change completely the way ships charter their routes, the masters are trained to think on each voyage, and the time/volume cargo partitions will reach their destinations.