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MAROFF-2-Maritim virksomhet og offsh-2

Cruising towards Zero Emissions - Development of innovative and integrated cooling and heating concepts onboard cruise ships

Alternative title: Cruiseindustrien mot nullutslipp - Utvikling av innovative løsninger for kjøling og oppvarming om bord i cruiseskip

Awarded: NOK 13.4 mill.

Cruising towards Zero Emissions (CruiZE) is a collaborative project between Norwegian technology suppliers, the world's largest cruise operator, SINTEF, and NTNU. The aim is to develop innovative energy efficient concepts towards a more environment-friendly cruise industry. The energy use for a cruise ship's hotel facilities, such as heating, ventilation, air conditioning and provision refrigeration (HVAC&R) averages 40% of the ships' total energy usage. This separates cruise ships from other ship segments where propulsion is by far the largest energy user. Traditionally, a cruise ship's energy demand is supplied by burning fossil fuels, leading to a high carbon footprint per passenger, and air pollution in ports. However, the cruise industry is facing ever more stringent emission regulations, both internationally, regionally and nationally. Today, the heating demands for ship hotel systems (such as space heating and domestic hot water) is primarily met by recovering waste heat from the engines, and supplemented with an oil-fired boiler. The boiler is only used when there is lack of waste heat, for example when connected to shore power in port, or when operating on batteries. For ships sailing in warm climates, the electric power for air conditioning (AC) is a major consumer, and is also produced with fossil fuels. Today's systems for AC and provision refrigeration use synthetic refrigerants, being harmful to environment and humans. During recent years, substantial R&D efforts have been made in developing energy-efficient propulsion and power generation systems. These include batteries, fuel cells, and engines using "greener" fuels. However, to achieve zero-emission operation in a cost- and energy efficient way, it is of key importance to reduce the energy usage of hotel facilities. Also, the change towards "greener" ships influences the total energy system onboard. This implies challenges for the hotel energy supply, such as a more varied availability of waste heat. The CruiZE project addresses these challenges, and tries to turn them into opportunities. This is done by developing innovative concepts that are well integrated with the ships' propulsion system and adapted to varying operating conditions. The goal is to come up with concepts that; enable zero emissions in ports, minimised emissions at sea, and achieve an average reduction in total energy use of 10-20%. The focus in CruiZE is on technologies related to: - HVAC&R systems using the natural refrigerant CO2 (with no negative environmental or health impact) - Improved utilisation of waste heat or cold, for example by use of thermal energy storage During the project several dynamic simulation models were developed. These were used to evaluate energy performance of novel concepts, accounting for ship's varying operating conditions. As input to these models, the cooling and heating demands for hotel facilities were estimated for different cruise ships. The characteristics of these "case ships" varies in terms of number of passengers, operational area and season, type of propulsion and fuel, and energy supply in ports. Results from evaluating the energy savings of various concepts are, to some extent, ship-specific. However, the results confirm a potential to reduce the energy use with at least 30% during sea passage, and to realise zero-emission operation during port stays or in environment sensitive areas. Further, there is a clear benefit with CO2 as refrigerant, to provide compact, flexible and environmentally-friendly HVAC&R systems. On ships with limited waste heat (partly battery operation) a CO2 heat pump could supply the heating needs with about one third of energy use compared to a boiler. The heat pump could also, simultaneously, supply parts of the cooling needs. Many cruise ships are today built for using liquefied natural gas (LNG) as fuel. Large power savings could be achieved by integrating the CO2 system with cold recovery from the fuel system. If the ship partly relies on battery operation, further relative improvement can be achieved with a cold energy storage. Generally, the results clearly show that thermal energy storage (both hot and cold) can play a key role in enabling periods of zero emission operation and maximising use of waste energy. A thermal storage with phase change materials (PCM), can significantly reduce the space requirements, but more R&D is needed on PCMs suitable for ship applications. To facilitate uptake of novel heating and cooling technologies on ships, a number of barriers were addressed. This includes, for example, the unclear regulations for implementing natural refrigerants, and that the hotel energy use is not addressed in environmental indices issued by regulatory bodies, cruise ports, etc. Also, the need for more operational data on ship hotel systems is considered crucial for the development and uptake of energy saving concepts. These barriers are now further addressed in other SINTEF projects.

CruiZE target group include ship operators, technology suppliers, cruise ports, maritime authorities, organisations, and research community. For the target group, the main project outcome is an increased awareness and knowledge about the significance of thermal energy systems on cruise ships, the so-called hotel systems. Specifically, industry partners benefit from new knowledge on natural refrigerants, thermal energy storage, and on how dynamic modelling can optimise systems. Collaboration with other research projects, led to knowledge sharing between shipping sectors, industry segments, and research disciplines. Instead of addressing technologies relying on heat recovery from the ships' fossil fuelled engines, the research focus was on innovative concepts valid for "greener" propulsion systems. CruiZE also adds to the research field on natural refrigerants and thermal energy storage, by evaluating their use in maritime application. Quantitative results on reduced energy use and emissions, are rather ship specific. However, together with the new-gained knowledge , the results will contribute to knowledge-based decision-making, being valid for ship owners, designers, technology and energy suppliers, authorities and ports. Three spin-off-projects initiated by industry partners show the need for further R&D, also in other ship segments, such as offshore supply vessels. Education of 1 PhD and 6 MSc, contributes to Norway's goal of increasing the maritime competence level. CruiZE has achieved its goal of developing concepts to reduce the ship hotel system's energy use with at least 30% during sea passage and to realise zero-emission operation during port stays or in environmentally sensitive areas. Since the novel concepts are also relevant for other ship types, their future implementation will have a positive impact on Norway's, EU's and IMO's work towards decarbonisation. New concepts supporting zero-emission operation is of high importance for Norway's cruise tourism and value creation. For ship owners, the novel concepts enable long-term regulation compliance, fuel savings, and market advantages. By being in the front of developing solutions for an increasingly large and global market, CruiZE and its spin-off projects, will contribute to secure Norway's position as a large global supplier of “green” technologies. CruiZE has clearly shown the importance of applying a holistic energy system approach in the shipping sector. Collaborations with new researchers and industries was established on this topic. CruiZE' addressed the following barriers for the uptake of innovative technologies: unclear regulations for using natural refrigerants on ships; hotel systems are not properly addressed in environmental indices for ships; lack of operational data on ship hotel systems. Activities to overcome these barriers were initiated together with industry partners and external stakeholder, and continue in other projects to facilitate uptake of result

The cruise ship industry is a global steadily growing market, representing an energy-intensive shipping sector. The energy consumption for the hotel facility systems on board, such as heating, ventilation and air conditioning (HVAC), freshwater generation and provision refrigeration, constitute on average 40% of the ship's total energy use. Traditionally, the energy demand for both propulsion and hotel facilities is supplied by burning fossil fuels, leading to a high carbon footprint per passenger. In addition, emissions of sulphur, nitrogen oxides and particles contribute to air pollution causing health problems in major cruise ports. The cruise industry is facing stringent regulations, especially in destinations like Norwegian ports and fjords. Current efforts towards "greener" cruise ships are to a large extent focused on novel propulsion systems. To realise low/zero-emissions, in a cost- and energy efficient way, it is of key importance to put more efforts to reduce energy usage of the hotel facility systems. Moreover, the new propulsion systems imply a significant change of the energy system, in terms of waste heat characteristics and heating/cooling load. The objective of CruiZE is to develop innovative heating and cooling concepts that are optimised for the ships' propulsion system and varying operating conditions, aiming at zero-emissions in ports, minimised emissions at sea and an average reduction in total fuel consumption of 10-20%. Solutions include technologies for waste heat/cold recovery, HVAC using natural refrigerants, compact thermal storage and concepts for proper integration into the total energy system. Development of dynamic numerical models will contribute to an efficient design and operation of the concepts, addressing the on-going digitalisation of the ship industry. Strong interaction among the project partners, representing cruise operators, ship designers and equipment/system suppliers, will ensure and promote a "greener" cruise industry.

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MAROFF-2-Maritim virksomhet og offsh-2