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Zero emission - Viking Princess
Fuel cells, advanced battery packs and electric power – zero-emission technologies are becoming an emerging force in the offshore industry.
Zero Emission - Hybrid - Viking Princess
The offshore service vessel Viking Princess is refitted with a hybrid power system that incorporates batteries.

The international shipping industry is facing an increasingly tight regulatory environment, especially when it comes to emissions to air. And with the recent decision to implement the global sulphur cap in 2020 and to add the North and Baltic Seas to the list of nitrogen oxide (NOX) emission control areas, the pressure is on. For zero- and low-emission solutions such as fuel cells, battery and hybrid technology, these developments have been a real boost.

The oil industry is also changing mindsets, and big oil companies have started focusing on technologies that could improve energy production and enhance energy efficiency and other efforts to mitigate the risk of climate change.

ExxonMobil, for example, is going to partner with two Singaporean universities to open a Singapore Energy Centre in 2019 to develop and improve green technologies. Total bought the French battery maker Saft Groupe to invest in clean energy and Statoil STI invested in the battery manufacturer Corvus. Statoil Norway is complementing its oil and gas portfolio with a partnership with E.ON investing in the German Arkona wind farm in the Baltic Sea. Shell and Qatar Petroleum’s Wave LNG Solutions signed a framework agreement to develop an LNG bunkering infrastructure at strategic shipping locations across the globe.

As one of Statoil strategic goal’s is to continuously reduce its operational footprint, the company has awarded contracts to five shipowners for seven supply vessels to support the company’s offshore activities in Norway. 

The key decisive factor in the selection process was the ability to operate in an environmentally friendly way. Vessels that could demonstrate low fuel consumption have therefore been successful in this award. Based on Statoil’s experience battery operation has a good impact on consumption and emissions. None of the selected vessels have a system for battery-operation or shore power yet. This equipment will however be installed, and the NOX fund is a key support player and contributor to the shipowners in their effort of installing batteries. The vessels will have DNV GL‘s Battery Power class notation, which allows them to use the battery as spinning reserve (saving fuel and maintenance cost) while working in dynamic positioning alongside the installations. Statoil is also offering fuel saving incentives to serveral shipowners for vessels that are capable of operating energy efficiently, thus reducing the total fuel costs. These and many more initiatives showcase the demand for a clean supply chain among the entire offshore sector, including support vessels and the different fuel technologies that can lead to greener operations.

Zero emission - Pa-X-ell
Project Pa-X-ell, one of the e4ships pilot projects, is putting high-temperature PEM fuel cells to the test on passenger vessels.

Hybrid battery technologies 

As presented at this year’s Maritime Battery Forum, batteries are currently a fast growing technology in shipping with a compound annual growth rate of about 40 per cent in terms of megawatt hours (MWh) installed battery capacity. 

In October 2017 the platform supply vessel Viking Princess, classed DNV GL, returned to service after being refitted with a hybrid power system that incorporates batteries. It is the first offshore support vessel on which batteries have been used to reduce the number of generators on board. According to Wärtsilä the hybrid system will generate savings through improved engine efficiency, as the operating profile of supply vessels is highly variable. When using the energy storage system on board Viking Princess, the fuel saving potential can be up to 30 per cent in various operations and the CO2 emissions can be reduced by up to approximately 13 to 18 per cent per year, depending on the operational conditions and requirements. The vessel now runs on a combination of a battery pack for energy storage and three liquefied natural gas-fuelled Wärtsilä engines. 

“To date, hybrid battery solutions have been mostly confined to smaller offshore supply vessels and tug boats, where they can handle spikes in power demand,” says Narve Mjøs, Director Battery Services & Projects at DNV GL – Maritime. However, innovative research conducted to develop batteries for the automobile industry means that today battery cells boast enhanced power density. The cost of lithium-ion battery cells has been lowered by up to 80 per cent over the past four years, making battery and hybrid technology a more attractive option for larger ship segments as well. One of the latest innovations in this field is a wireless charging solution offered by Wärtsilä. The first 1 MW fully automatic charging station for a coastal ferry has been installed in September 2017.

Electric shore power 

In August 2017, the offshore vessel KL Sandefjord, owned by “K” Line Offshore in Norway received DNV GL’s “Shore Power” class notation. The new certification will allow KL Sandefjord to perform cold ironing, which means the vessel will be able to shut down its engines and rely on a shore-based electrical supply during berthing at port. Vessels are able to reduce their fuel consumption and eliminate various related emissions by employing cold ironing or using onshore electricity sources. 

The process is also helpful in improving air quality at the port and surrounding environment, since it helps reduce the levels of nitrogen oxide (NOX), sulphur oxides (SOX) and carbon dioxide (CO2) emitted from the ship.

Zero emission - Sandefjord
KL Sandefjord is the first offshore vessel with DNV GL’s “Shore Power” class notation.

A new generation of fuel cells

Another low-emission technology which has gained traction is fuel cells. Fuel cells are quiet, efficient and cause no noticeable vibration. The European Maritime Safety Agency (EMSA) contracted DNV GL to provide a technical study on the use of fuel cells in shipping to evaluate the potential and constraints as prime movers and energy sources in shipping. The technology overview includes the major maritime fuel cell projects to date. The second chapter is dedicated to current applicable standards, regulations and guidelines for bunkering, on-board storage and distribution of fuel as well as use of on-board fuel cell installations. Finally, a risk assessment study to analyse possible safety challenges for maritime fuel cell applications on ro-pax vessels and a chemical tanker investigated 148 failure scenarios related to the usage of the three different types of fuel cells and fuels. As a result, for a total of 100 scenarios, additional mitigation actions were recommended. Taking these recommendations into account, the analysis team recognized that tolerable risk levels (ALARP) could be reached with respect to operational and human safety.

In Germany, leading German shipbuilders, shipowners, suppliers and DNV GL have joined forces in the fuel cell project e4ships. Launched in 2009 with support from the German government, e4ships aims to develop technical solutions for the implementation of fuel cells in marine applications and feeds into the development of international regulations on fuel cells.

To make this technology safe to use and commercially viable, the e4ships consortium has developed fuel cells capable of running on low-sulphur diesel or methanol, and has tested them in several pilot projects. Currently, the e4ships project partners are focusing on the next development steps and prototype tests as well as the design of decentralized on-board networks comprising several fuel cells. Project phase II is scheduled to continue until 2021 – the ultimate goal is to present production-ready technologies.

Regulatory work with impact

New insights, generated by e4ships and its pilot projects, have already made an impact on the shipping world. “The results of the first phase have made an important contribution to the IMO’s International Code of Safety for Ships Using Gases or Other Lowflashpoint Fuels (IGF Code), which entered into force in January 2017. The code is an important prerequisite for fuel cell technology to reach market maturity, and we are very proud to be part of that,” says Dr.-Ing. Gerd Würsig, Business Director Alternative Fuels at DNV GL – Maritime. 

The code contains mandatory provisions for the arrangement, installation, control and monitoring of machinery, equipment and systems using low-flashpoint fuels, focusing initially on LNG. It addresses all areas that need special consideration for the usage of low-flashpoint fuels, taking a goal-based approach, with goals and functional requirements specified for each section forming the basis for the design, construction and operation of ships using this type of fuel. Technical provisions for other low-flashpoint fuels can be added as new chapters to the Code, but in the meantime, ships installing fuel systems to operate on other types of low-flashpoint fuels will need to individually demonstrate that their design meets the code’s general requirements.