Zero Emission Vessels – What Needs to be Done

This Report  was commissioned by Lloyds Register  and the Sustainable Shipping Initiative (SSI) and the research was undertaken by UMAS (the University Maritime Advisory Service) and published in May 2018.

UMAS is now working on a new report dealing with Low Emission Vessels.  Carlo Raucci from UMAS is speaking at the European Hydrogen Ports and Maritime Policy Conference to be held in Brussels on 8 November.

The objectives of the May report were to:

• Understand technology options that represent viable routes towards Zero-Emission Vessels (ZEV) for SSI Members.
• Understand the economic implications of adopting ZEV enabling technologies for SSI Members.
• Identify and support enabling drivers toward ZEVs.

Three technology groups were examined.  These were hydrogen fuel cells, electric vessels and biofuels and their suitability for use in Bulk Carriers, Container Ships and Tankers was examined.

The Report argues that the economic feasibility of ZEVs is highly dependent on the regulatory and economic environment that shipping operates in.  In view of this situation a scenario based approach has been used.    Two scenarios were examined and the assumptions for hydrogen were as follows

Scenario 1

• Hydrogen is produced largely from fossil energy sources and will be available to shipping worldwide at $2 per kilogram by 2030.
• In 2030, CO2 emissions from hydrogen production are relatively high at about 5.6 tonnes of CO2 per tonne of hydrogen. It is assumed that hydrogen will get cleaner over time reaching 3.82 tonnes of CO2 per tonne of hydrogen.
• In terms of the fuel cells, marine fuel cells are available at any power requirement.  However, they are mainly used in combination with gaseous hydrogen with a reformer.  Capital costs are $900 per kw and efficiency is close to 40%
• In terms of hydrogen storage, liquid hydrogen is developed but not as well as storage in gaseous form.  It has a capital cost of $300 per kilogram and it is assumed to have an efficiency of 60%.

Scenario 2

• Hydrogen is expensive and only green hydrogen is used in shipping to ensure zero emissions
•  In terms of fuel cells, further improvements are made in efficiency using heat recovery systems and reaching 75%.  As a consequence, capital costs increase to $1500 per kw.
• In terms of hydrogen storage, further improvements are made in tank insulation and efficiency increases to 80%.  This together with its use in combination with more efficient fuel cells encourages mass production with a reduction in capital costs to £30 per kg.

In its examination of the Low Emission fuel, UMAS concludes that none of the technologies are more profitable than a conventional ship and this means that there needs to be changes to regulatory policy as an enabler.

The study also analysed the profitability of ZEVs with a changing carbon price and concluded that there needed to be a policy change in this pricing to ensure the uptake of new technologies.

The Report concluded that advanced biofuels “may represent the most economically feasible zero-emission alternative for the shipping industry.”  However some positive comments were also made about hydrogen.  The Report’s conclusions stated that “for hydrogen fuel cell options, the associated costs of the technology on board (both hydrogen storage and the fuel cell) weighs significantly on the overall profitability.   However, given certain projections used in  this report, these costs may not be prohibitive, particularly if the development of the technology and its efficiency is encouraged through other industries or through policy changes.

Particularly when exploring the hydrogen option, it is important to take into account the range of  different hydrogen approaches.  For example, electrolysis with renewable electricity can be used to produce ammonia (indirectly from hydrogen, or directly), which is less costly to store on board.  Both hydrogen and ammonia can be used directly in internal combustion engines which can also help control capital costs.”

The voyage costs include the high cost of hydrogen.  The Conclusions argue that these “remain the largest contributory factor to the poor competitiveness of hydrogen fuel cells.  This becomes particularly apparent when preference is given to the greenest supply of hydrogen, given the costs currently associated with renewably generated electricity and electrolysis technology.  This gap in competitiveness does show great potential for reduction, even with the timescales used in this study – out to 2030.  With the ability to pass on voyage cost excess to the supply chain, effectively providing a premium on a zero emission service, the magnitude of the competitiveness gap decreases hugely and may indeed already render hydrogen fuel cells economically feasible for certain operators and routes.”