In recent years, the IMO has accelerated regulatory efforts to cut the carbon intensity of all ships by at least 40% by the year 2030 and make the industry net zero by 2050. Because of this, creating an alternative fuel source has become a necessity, and many companies are now working towards that aim.
Nuclear propelled ships are by no means new; they have been used in the past, perhaps most commonly on nuclear submarines, but examples can also be found in surface vessels such as Russian icebreakers and the NS Savannah as far back as 1959. Generally, nuclear has proven itself to be a stable means of propulsion. Still, safety concerns, along with the fact that initial installation costs for a nuclear reactor have traditionally been so high has put many shipping companies off using them. However, with fuel costs currently so high, could nuclear power save ship owners thousands in the long run and help the sector meet its 2050 obligations?
Nuclear energy has been used in the past, but it has never been fully commercialised in the merchant sector due to challenges around the training of seafarers, cost effectiveness, piracy and terrorism, the current lack of legal frameworks, and environmental issues. Here, we will examine these questions and ask whether nuclear energy could now be the solution for reaching net-zero by 2050.
Nuclear power and the maritime industry today
Nuclear power was first introduced to the shipping industry in 1955 when the U.S. Navy developed its first series of ship borne nuclear power plants. This then evolved into the development of high-performance submarines and surface ships. It is estimated that 100 nuclear reactor warships are in use in countries such as the US, Russia, China, France, the United Kingdom, and India. Russia has also developed nuclear icebreakers and floating power plants.
When nuclear power was first introduced, it was said to be the next big thing and was predicted to replace the use of fossil fuels in cargo ship designs. In 1959 a prototype, NS Savannah, was launched, becoming the first ever nuclear powered merchant ship. The ship was in use until 1972, but due to the high cost of operations, the vessel was then decommissioned.
The combination of high oil prices and an emphasis on the need to reduce fossil fuel consumption has reignited the interest in using nuclear power onboard commercial ships. The United Kingdom Maritime and Coast Guard Agency has begun creating regulations for nuclear-powered ships, both for UK flagged vessels and international nuclear vessels hoping to visit UK ports. The IMO has also created regulations for the existence of nuclear ships under the Code of Safety for Nuclear Merchant Ships even though the NS Savannah was the last built of its kind.
Recently there have been fast and major improvements in the nuclear field. It is attractive to the maritime industry given the combination of larger vessel tonnage, higher demands for trade, the increase in prices, and the pressure to reduce fossil fuels to address climate change. There has been reluctance in making any major changes without the certainty of major nations allowing the berthing of atomic ships at their ports.
With the MCA beginning to produce frameworks for nuclear ships, it sets a benchmark for other countries worldwide to enforce similar legislation. Nuclear propulsion appears to be the fastest way to decarbonise the shipping industry, which is why such emphasis is being placed on the possibility of making this a reality. Companies such as Earth 300 Ventures, have dedicated their time to environmental research and technology development and have announced their aim to create a research vessel that is controlled by nuclear power, using a salt reactor.
As mentioned previously, the IMO expressed its wish to reduce greenhouse gas emissions from the shipping industry by at least 50% by 2050, with efforts towards zero emissions as soon as possible.
What is nuclear power?
Nuclear energy is derived from nuclei, which are the core components of atoms made up of positively charged particles called ‘protons’. Nuclear energy can be produced in one of two ways:
Nuclear Fission
Atoms are submicroscopic particles found in molecules. They are made up of protons, neutrons, and electrons, that together form the building blocks of all liquids, gases, and solids. At the centre of an atom is the nucleus, which contains protons and neutrons surrounded by electrons. Protons carry a positive charge, electrons carry a negative, and neutrons don’t carry a charge at all. With all of this, a huge amount of energy is present which bonds the nucleus together. However, breaking these bonds by using a process called nuclear fission causes the rapid liberation of energy from the atom. If harnessed correctly, it is possible to use this powerful energy to generate usable electricity.
During nuclear fission, a neutron collides with an atom which causes it to split. When the atom is then split, it releases a large amount of energy in the presence of heat and radiation. When the atom splits, it produces more nuclei which are themselves then split again, repeating the process on itself. This is known as a nuclear chain reaction. To maximise the yield from this process, neutron-rich elements known as isotopes are used as feed stock. Of these, the most unstable are used such as uranium and plutonium. These are known as radioactive isotopes.
Nuclear Fusion;
Nuclear fusion is essentially the opposite process, where atoms are combined or ‘fused’. It is the process where two atomic nuclei combine to form a single heavier one, resulting again in the release of a massive amount of energy.
Fusion reactions occur in a state of matter called ‘plasma’, which is an ultra-hot, electrically charged gas made of positive ions and free-moving electrons with unique properties that differ from solids, gases, or liquids. This fusion powers the sun and stars. However, for this reaction to occur, the atoms must collide at the very high atomic speeds only possible at ultra-high temperatures so that they can overcome their mutual elecro-magnetic repulsion – both are negatively charged. Once the nuclei are within close range of one another, the attractive nuclear force between them outweighs the electrical repulsion, allowing them to fuse. For this to occur, the nuclei must be within a confined space to increase the chance of collision. Since the massive pressures present in the sun’s core are not replicable on earth, synthetic nuclear fusion requires the attainment of temperatures 10 times that of the sun’s surface. Because of this, there are real challenges to overcome in reactor design and the cost and difficulty of creating sustained nuclear fusion on earth makes it a commercially non-viable form of generation at present.
Nuclear Fusion is still being researched, with many private companies worldwide taking a keen interest in the advancement of the energy source. It is expected to be commercialised within the next 20 years. Recently, there have been multiple breakthroughs in nuclear fusion, with many experts believing that it really could hold the key to climate change and the energy crisis. The first successful nuclear fusion was recorded in August 2021, but laboratories around the world have since failed to replicate the results.
Nuclear fission, on the other hand, has been in use for decades and is responsible for providing around 10% of the world’s electricity. Highly advanced designs have increased safety as a result of amendments to the technology. This is due to an increase in private investors contributing to the manufacturing and the modernisation of regulatory frameworks.
At present, advanced nuclear energy consists of two major systems which are generation III+ and generation IV. Generation III+ uses water reactors, standardised designs, and mass produced parts to enhance passive safety and produce less waste. Generation IV systems are still being developed, but it is predicted that the new reaction designs will provide a range of benefits, such as improved safety, reduced waste, and cost effectiveness.
Why should nuclear energy be used onboard ships today?
It’s already been established that the use of nuclear propelled merchant vessels is a proven possibility. The NS Savannah was the first ever nuclear propelled cargo/passenger vessel, but she was decommissioned due to the cost of keeping the vessel running. Today, crude oil pricing is itself becoming harder to bear and global trade is much larger, with more goods being shipped than ever.
In addition, the IMO announced in 2018 that the aim is to cut annual greenhouse gas emissions by at least half by 2030, and work towards phasing out greenhouse gas emissions from shipping entirely as soon as possible within this century. Incorporating nuclear energy into the maritime industry would absolutely accelerate carbon-free shipping. Nuclear energy does not produce direct carbon dioxide emission, meaning if used, it would reach the IMO’s aims of being GHG free overnight. It would also ensure that companies could avoid carbon taxes that have been set, but also sell carbon credits to others in the same way that Tesla does with electric cars.
Today’s maritime industry needs to support ships such as supertankers and container ships, meaning they need to support powerful engines and fission technology has proven to do so with the example of large aircraft carriers and naval crafts. It’s been suggested that by using nuclear energy, vessels would not need to take on bunkers for over 20 years, making it ideal for merchant vessels that are required to be at sea for long periods of time.
Although there are naval engineers who are qualified to operate nuclear powered ships, it does pose a question over the potential setbacks it may bring the maritime industry with regard to having qualified personnel to operate the reactors. The Royal Navy requirements for submariners explain that after basic training is completed, a submarine engineer must complete a 10-month full time Diploma in Nuclear Reactor Technology to qualify to operate the machinery. As it stands, nuclear reactors are not included in the maritime curriculum for merchant engineers. This would suggest that should nuclear energy be incorporated into the mainstream, plans must be in place to ensure that competent personnel are available to use the equipment.
Is it possible for nuclear energy to be incorporated into the shipping Industry?
The global nuclear energy sector is going through one of history’s most innovative and transformative periods. When most lay people think of nuclear energy, they think of huge power plants and find it hard to imagine how such a concept can be incorporated aboard a ship where space is at a premium and operating conditions are often challenging. However, in recent years, much work has been done to develop Small Modular Reactors (SMR’s). Compared to regular-sized reactors, SMRs have a much smaller footprint, which means they can be built in a shorter timeframe and then shipped out to the installation site.
The World Nuclear Association defines SMRs as being nuclear reactors of generally 300MW or less. Currently, a large ship is only required to run on 80MW of main engine power. However, Bill Gates is currently working on an SMR capable of producing 345MW of fusion thermal power, capable of propelling a convoy of 4 to 5 ships to speeds of up to 20 kts. The reactors are built on-site in factories and have standardised designs, which means they can be produced at scale, reducing cost and lowering the risk of construction delays. As they are built onsite, it can reduce preparation time and construction costs as well as making it possible to send them to remote locations.
Molten Salt Reactors (MRS) are also a contender for supplying nuclear energy to the maritime industry. MRS is lauded as a newer, safer type of nuclear reactor and could be on par with the cost of more conventional low emission fuels, which could make them more desirable. MRS also has a long life expectancy, with ships needing to refuel every 3-30 years depending on the design and type of fuel that has been used. According to Lloyds Register and companies such as TerraPower and CorePower which are in the midst of developing MRS, aims are to build the reactors so that the fuel would last the same amount of time as the life expectancy of the ship (25-30 years). This means that they would need no refuelling after the initial build of the ship, removing the logistics, as well as the combustion cycle, of traditional fuels. Using reactors will also free up space onboard the vessels, allowing additional cargo to be stored as the need for a large volume for bunkering would no longer be required.
However, although nuclear energy is capable of being installed on merchant vessels, it seems that it can only be installed on new-build vessels. A draft of the MCA’s MGN for Nuclear Ships gives an insight into the regulations to be expected for the construction of nuclear vessels. It highlights that;
- The MCA should be approached in the early stages of construction and design so they can approve the vessel.
- The reactor installation is the ship’s main propulsion system
- The reactor installation should be designed having regard to the special conditions of service onboard the vessel in both normal and expected circumstances
- The design, construction, and standards of assembly and inspection should comply with the requirements in the 2021 regulations of the Nuclear Code and be subject to the approval of the MCA in light of limitations
Certainly, with the reactors needing to be installed on newly specialised designs, it will come at a cost. Nuclear energy is usually considered expensive due to the large upfront costs for the building and fuel. The builds look at the lifetime cost of operations, including refuelling (if necessary) and fuel disposal. Current fossil fuel engines need the initial upfront cost as well as the cost of the continued fueling. In June 2022, bunkering costs soared to an average of $1,125.50 per mt. Considering a VLCC when loaded can consume up to 70mt a day, the daily fuel burn would cost the operator $78,785. The cost for an SMR can be anywhere from $5,500 -$8,100 per KW. As there hasn’t been a nuclear propelled merchant ship designed since the NS Savannah, it’s difficult to gain an accurate figure for total costs in the contemporary context. The NS Savannah cost $46.8 million ($28.3 million of which was on a nuclear reactor and fuel core), which in today’s money would equate to over $518,400,000.
Problems with Nuclear Energy
When talking about nuclear energy, the first concern that many people think about is the nuclear disasters that have occurred such as Chernobyl, Fukushima, and Three Mile Island, along with the legacy of radioactive waste that could remain for thousands of years. Many environmental organisations such as greenpeace have recently questioned the safety and security aspects of nuclear ships, should they be hijacked. Shipping routes such as the Gulf of Aden are among the most popular routes for terrorist and pirate attacks. The threat from piracy or hijacking of a nuclear vessel are self-evident.
Nuclear expert at Greenpeace, Jan Haverkamp told E&T;
“Over the years, nuclear shipping has had its fair share of incidents; there was the whole Kursk affair (a nuclear submarine that sank in an accident in the Barent Sea in 200, killing 118 personnel onboard) and a host of reactor problems, including during construction and maintenance. Norway is investing hundreds of millions of euros to help Russia take apart its decommissioned ships to reduce the risk of radioactive pollution”
Most reactor related accidents are caused by a loss of coolant that will trigger a chain reaction generating explosive heat. Ships are constantly moving and are exposed to external factors such as temperature oscillation, wind and water resistance, collision and corrosion, which will increase the risk of an accident.
The sinking of a nuclear ship could be catastrophic to the marine environment. Radioactive substances are easily detectable from the use of one single radioactive atom. From that, experts can also tell the type of decay released and what kind of isotope is used.
As it happens, nuclear waste has been dumped into oceans for years. The United States was the first country to dispose of nuclear waste into the ocean in 1946, and whilst the London Convention banned the dumping of high-level radioactive waste in 1993 many countries still allow this to happen. In 2021, The Government of Japan was planning to dump 1.25 million tonnes of radioactive water, containing Tritium into the Pacific Ocean. This is enough to fill 500 Olympic-sized swimming pools. Although it is believed that Tritium may be harmful to humans in large doses, when diluted with water it would reportedly pose no threat to human life. However, local fishers believe that dumping the wastewater into the ocean will devastate their livelihoods. If enough waste is dumped, it will eventually make its way into the marine ecosystem.
However, nuclear vessels would be designed in the knowledge that they are exposed to external threats and all possible precautions could be taken to ensure that the nuclear reactor would be adequately secured in the event of an emergency.
If the vessel were to sink, salt water acts as a natural insulator against radiation as it absorbs the neutrons released by the reactors, potentially protecting survivors and rescue workers within the vicinity. Saltwater is naturally filled with Uranium, a key component in nuclear fuel. Losing a reactor would cause harm to human life and the environment, but it is suggested that the threat could be reasonably contained in the case of immersion.
Another cause for concern regarding nuclear powered vessels is whether coastal cities around the world would allow them to enter their ports. Currently, the Suez Canal Authority does not allow nuclear powered vessels to sail through it. The Suez Canal is one of the world’s busiest waterways, and nuclear vessels unable to enter it may discourage many shipping companies from going nuclear. Only on very rare occasions would the canal allow nuclear powered vessels to enter through it, the threat of breakdown while sailing it too much of a risk, as it would cause closure and result in loss of revenue.
Key and Emerging Players in Nuclear Shipping
Over the past 10 years, a small number of companies have begun developing small-scale nuclear reactors capable of propelling large ships. As the maritime industry is taking steps in moving forward to the industry, zero-carbon nuclear reactors may be the future.
NuScale Power is an American company specialising in designing and creating small nuclear reactors. Its mission is to provide scalable advanced nuclear technology by creating an energy source which is smarter, cleaner, safer and cost-effective. Their ambition is to create clean energy which has a small environmental footprint per government guidelines. The company has created The NuScale VOYGR small reactor, which is designed to offer carbon-free energy and reduce financial commitments.
Prodigy Clean Energy is another company which develops small modular reactors, especially for marine power stations that will pioneer a new generation of safer, low-cost and accessible nuclear energy.
Core Power is a high profile developer of nuclear propulsion for merchant vessels. They are developing what will become a licensed type-approved nuclear-electric power package for ocean transportation. They are aiming to develop and design a nuclear reaction that will result in a competitive true-zero emissions system by 2030.
Ulstein is a marine enterprise which designs, builds and sells merchant ships. They are currently in the process of developing a nuclear propelled cruise ship. The vessel’s concept can make the vision of zero-emission operations a reality.
Conclusion
Nuclear energy in the maritime industry is at an uncertain stage of development – the technology is available and the principal is proven, but questions remain on safety, security, and capital expenditure. However, if taken seriously, it could be a keystone to efforts towards reaching net-zero. Nuclear reactors are a profoundly compelling fuel source for all sorts of applications, but whether it will become a feature of the civian shipping industry by 2050 is hard to imagine.
Nuclear fusion isn’t yet a technological reality with scientists still trying to ignite fusion reactors successfully. Although breakthroughs are predicted and the concept packed full of tantalising possibilities for solving the world’s problematic energy future, there is no telling when this will be the case. It could take over a decade for reactors to be developed suitable for ships. Even then, it could take longer for them to be approved by different flag stages and the IMO. The implications of fusion reactors and their effects on the environment should an accident occur at sea is still unknown as there is still no working prototype.
On the other hand, nuclear fusion and small-scale reactors have been in use for decades and they have been proven to work. However, the installation cost has prevented ship owners from installing them in the past. The rising fuel prices worldwide are at an all-time high, with ships needing to bunker every time they enter a port, making it cost and time consuming. Although the initial cost of installing a nuclear reactor onboard ships is expensive, in the long run, it could potentially save the ship owner thousands as nuclear propelled ships do not need to be refuelled for up to 30 years.
For nuclear reactors to be incorporated more in the merchant sector, more work must be completed on the rules and regulations set by different government bodies. Currently, the MCA is working on its guidelines for nuclear-powered vessels, promising for the nuclear sector as more countries may follow. There is cause for concern for the political side of nuclear powered vessels, meaning that more universal frameworks set out by governing bodies need to be completed to promote the safe transportation of nuclear bourne vessels entering different world ports.
Although there are a lot of setbacks to using nuclear power to propel vessels, there is a market for them. More work and research need to be conducted on the implications of having a vast amount of nuclear propelled ships on the oceans, they are also a great alternative to marine fuel, which could see the IMO’s ambitions of reaching net-zero achievable, but by the year 2050 is still undeterminable.
