IMO is set to cut the carbon footprint of shipping. The upcoming 7th HullPIC conference gives better insights into the industry’s psyche in seeing the EEXI and CII writing on the wall. By organizer Volker Bertram
The Big Zero is the long-term goal for the second half of the century, but as in football, the next opponent is a[ds_preview]lways the hardest. And next one up is EEXI and CII, mandatory as of 1st January 2023. The EEXI is the Energy Efficiency Existing Ship (Design) Index, akin to the EEDI for newbuildings, expressing the theoretically achievable energy efficiency for the ship as designed, in prime condition as in initial sea trials. The CII is the Carbon Intensity Indicator, calculated based on IMO’s fuel oil DCS (Data Collection Scheme), where the requirement to just monitor is now enhanced by grading the performance each year from A to E. Poor operational performance (E once or three consecutive years D) will entail mandatory action to improve performance, planned, documented, tracked, and audited in a SEEMP. So far, this summarizes the plan in a nutshell, where the big picture is known to most in the shipping community, but the devil lurks in the details, as always.
EEXI and CII cast their shadows ahead already. There is a certain tension in the air, reminiscent of pre-exam stress. What if the verdict – for some of the ships in a fleet – is »you have been measured and found wanting«? Not everyone was a straight-A student in university days, and not every fleet manager will have straight-A scores for his ships. Best to take a mock exam first to see how much we have to worry. But that at best gives only an indication, and we don’t just want to pass, we want to be best of class. Can we get some extra credit doing this or that? Rumors float around the corridors how you might argue for special status and pass that way. And most students play it safe, work hard and actually improve to pass the exams. But analogies carry you only so far. The upcoming 7th HullPIC conference gives better insights into the industry’s psyche in seeing the EEXI and CII writing on the wall.
It’s the speed, stupid
Suppose your energy efficiency is not good enough. What can you do to improve it? IMO gives some first pointers with its GHG studies and its GloMEEP website. To modify Bill Clinton’s campaign slogan slightly: »It’s the speed, stupid«. Older ships were often designed for much higher speeds than used in current operation. Engine power limitation (EPL) is then expected to be a measure adopted by many ships to achieve EEXI targets. EPL may come in various forms, e.g. through fuel index limiters or deactivating cylinders. Alternatively, one may consider ShaPoLi, a more recent entry to our acronym list. Shaft Power Limitation uses torque monitoring and an additional control unit to ensure the power limitation. In emergencies, this can be overridden. Another advantage is that the required sensor and monitoring equipment adds valuable data for performance monitoring insight. »[We] explore the possibilities of ShaPoLi as an accelerator of telemetry installations within the maritime industry«, says Hauke Hendricks, Head of Sales at Hoppe Marine, in this context.
The second-biggest lever after speed reduction (with associated power reduction) is better hull management, where a standard reference is given by the Clean Shipping Coalition which estimates that 10 % of the world fleet’s fuel consumption may be saved through better hull management, i.e. better coatings and cleaning strategies. Ships typically gain on average 7 %–10 % per year in resistance and thus fuel consumption at given speed due to progressive fouling and hull roughness. Cleaning, in drydock every 5 years or in between in water, restores the performance at least partially again, resulting in characteristic zig-zag curves in performance over time.
Coating and the CII
Better hull management aims at smaller slopes of the zig-zag curves through better antifouling solutions with less degradation in performance, and overall lower peaks through shorter cleaning intervals. One of the problems here is that currently most popular self-polishing copolymer (SPC) antifouling coatings degrade rapidly with conventional cleaning, reducing the lifespan of coatings with increased cleaning frequencies. As a consequence, premature drydocking for recoating to avoid dramatic performance loss with largely eroded antifouling protection may be needed. The potential for energy efficiency improvements is there, but cleaning strategies need to be adapted to different (and for some operators new) coating systems. »Hull coatings can have a significant impact on CII, as proven in performance monitoring, but operators need to be aware of implications of different coating technologies,« points out Stein Kjolberg, Global Category Director Hull Performance at Jotun.
The key word here is »proven«. Much of the discussion in the community is around reducing uncertainties for better decision making. How can we more accurately predict energy savings for assorted technologies? And how can we track and verify these savings, both for future decisions and for performance-based contracts, e.g. between charterers and owners? Richard Marioth, founder of Idealship, brings it to the point: »Monitoring per se does not improve energy efficiency, but insight gained from it leads to better decisions.«
Hapag-Lloyd on board
Better decisions in how to operate ships, for example. It has long been suspected that performance monitoring feedback to crews also has an indirect training effect changing crew behaviour towards better energy efficiency. One of the highlights of HullPIC 2022 is a paper by Martin Köpke, Manager Fleet Analytics & Technical Optimization at Hapag-Lloyd, with a detailed confirmation of the effect of sharing operational insights with the crew: »In order to achieve a higher level of transparency and mutual understanding, Hapag-Lloyd introduced automated feedback to vessel crews for all 250 operated ships. Each reported value is compared to an expected value which is based on a virtual model of each individual ship. This way the crew is immediately aware of reporting errors, measurement errors and possible excess consumptions.« The contribution is all the more valuable, as it also reveals unsuspected hurdles encountered during the initial implementation.
Better decisions through performance monitoring applies also to the assessment of energy saving devices, which enjoy increasing interest in the context of the EEXI and options to improve it. For energy saving devices, the best way to assess their effectiveness is long-term monitoring. But often ship owners don’t have the luxury of such experience with proven savings for their type of ships and operational profiles. In many cases, »it’s complicated.«
CFD application
For propulsion improving devices (PIDs), i.e. assorted nozzles and fins intended to improve the propulsive efficiency of the propeller, traditional model basin tests suffer from large scale-effects, as neither boundary layer near the propeller nor propeller rpm can be similar in model tests. Instead, CFD simulations for full-scale conditions have become state of the art in the industry. »The new [EEXI] regulations and trends in shipping pressure ship owners to quantify the effect of these devices, giving rise to an uptake in CFD application for this purpose,« reports Inno Gatin of In Silico, whose »Cloud Towing Tank« has been busy with such investigations for the past 12 months. He will share his findings in an attempt to draw general observations on the effectiveness of different PIDs. While the CFD methods as such may be very mature by now, the actual assessment of PIDs is not yet. The industry still focusses on design conditions, in the simulations and in the sea trials for verification.
Off-design conditions
This may be understandable in view of achieving a certain EEXI value, but for the larger picture, for reducing the long-term carbon footprint, we should look at performance in off-design conditions. How does a given PID perform at lower speeds that are much more frequently found in the operational spectrum? And how do changing boundary layers due to increasingly fouled hulls impact a PID’s effect on the propulsive efficiency? At least, these questions are discussed at HullPIC. Raised awareness is already a step in the right direction.
Wind power
The issues become even more complicated for wind-assisted ship propulsion (WASP) systems. For sure, they will save fuel, but business cases and energy saving metrics require quantification, again not just for a design condition, but for a realistic operational profile. Sofia Werner, Manager Strategic Research at the Swedish ship model basin SSPA gives a glimpse into the issues: »The number of [WASP] installations is predicted to increase rapidly in the coming years, and thereby the number of different technologies and makers. This development calls for standardised procedures for validation of the [WASP] performance in full scale. However, such standard procedures or guidelines are still lacking.«
Her team proposes a methodology based on short sea trials, combined with CFD modelling and statistical voyage analysis. Still, business cases are by their very nature particularly difficult for WASP installations as both variations in operational speed and operational areas strongly affect the saving potential. In one DNV study for a Flettner rotor on a tanker, the range was 1.4 % to 41 %, to give an idea. This is a handicap for vendors of WASP technology, but time seems to be on their side, and increasingly a broad spectrum of operational assumptions yields acceptable business cases. Performance monitoring also gets more complicated for WASP systems.
»The simpler the propulsion system on a vessel, the easier it is to obtain reliable results quickly. However, vessels will become more complex, [e.g.] harvesting energy from the environment,« says Falko Fritz of Skysails Marine Performance, based on his experience both with kites and performance monitoring. One of the issues here is that standard performance monitoring based on ISO 19030 filters out data sets above Beaufort 4, as wind speeds and resulting forces are afflicted by high uncertainties. But it is for these higher wind speeds where WASP systems harvest the most savings.
Faster and better monitoring
Much of the discussion at HullPIC in May is expected to be on the CII. All details for the CII calculation (including details of interpretation by authorities) are not yet on the table, but a sometimes-heated discussion has already started. The CII will be assessed on a yearly basis, but this may just be too slow in some cases to address corrective measures, for example in hull management. We need faster and better monitoring with early warnings allowing timely response, linking state-of-the-art performance monitoring to CII energy efficiency rating.
Charter party contracts are likely to require a minimum C rating both at start and end of the charter duration. In any case, the traditional charter party contracts need updating in light of the coming CII scenarios.
Adaption of charter parties
IMO makes the owners responsible for the CII grades achieved, but the charterers make the operational decisions that ultimately decide the CII. This »whipping boy« scenario can only be managed by adapting the charter party contracts to align responsibilities and operational decisions.
That we will see such changes is certain, how exactly we will draft and live such future contracts, we will see. It is safe to say that discussions will continue well beyond 2023, and performance monitoring schemes will increase in importance, before finally coming to come to a shared, transparent and objective view of a ship’s performance.
EEXI and CII pose new challenges and hurdles for the shipping industry. Most stakeholders work hard together to get fit for the future to take these hurdles. But at the same time, another discussion is starting on whether it wouldn’t be possible to take an easier route, trying to find some loopholes. It lies in the nature of new, major regulations that there are teething problems that were not foreseen when drafting them, but now stir up the industry where some shout »foul« and others shout »just clever«. Exploiting loopholes may not be fair, but it is legal and human. It is up to the regulators to identify loopholes and close them by updating regulations and interpretation guidelines.
Stricter ship type definitions
For example, the EEXI like the EEDI is ship type specific. That makes sense. Containership are slender and operate at higher speeds, bulk carriers are bulky and operate at lower speeds. Let’s compare apples with apples, and pears with pears, thought the authors of IMO’s EEDI/EEXI regulations, using different baselines for required values for a given ship size. But what if you transported some containers on a bulk carrier and then submitted this ship as »containership«? This loophole can be closed by adding stricter definitions of the criteria for assigning »ship type« baselines to a specific ship, based on design and cargo records.
Or one can seek to exploit leeway in measuring and calculation procedures. For example, there is the discussion on the weather factor in the computation of the EEDI. The basic intent of the weather factor is good, reflecting that ships usually operate not in sea trial conditions with calm weather, and that ships with lower energy requirements in realistic ambient conditions should be rewarded with a better energy efficiency index.
The problem lies in the uncertainties in determining the speed loss in waves and the flexibility given in the regulations. Deliberately choosing assessment tool and calculation parameters in one’s favour could be used to improve the energy efficiency index on paper without corresponding improvement in real energy efficiency of the ship.
Let’s be realistic
Shortcomings in details are not justification to reject IMO’s efforts to decarbonize shipping. Teething problems are normal. Awareness and open discussion allow timely responses to existing loopholes. The current state of energy efficiency assessment and monitoring is not perfect, but we have come a long way in the last seven years, when HullPIC started to bring together technology providers and users, and new challenges rather seem to fuel the dynamics in the community.
