Could a nuclear-powered cargo ship pass through the Suez Canal?
Ongoing small-scale nuclear energy conversion research has advanced to dramatically increase safety with the development of sodium-cooled reactors and molten salt nuclear technology. Although the technology is potentially feasible, there remains the need to negotiate to obtain passage through several channels and ports at the international level.
The history of nuclear ship propulsion dates back to the mid-1950s, when the United States developed the submarine. Nautilus. At the end of 1959, the Soviet Union responded to the challenge of nuclear propulsion with the launch of the Icebreaker Lenin. Since then, all nuclear-powered maritime vessels have been directly or indirectly linked to a national army or navy. Recent advances in nuclear technology offer the possibility of commercial propulsion application.
Environmental concerns regarding greenhouse gas emissions from the maritime sector have prompted the research and development of a multitude of alternative fuels and ship propulsion technologies. While alternative fuels such as LPG and methanol fuels support the operation of internal combustion engines, other fuels such as hydrogen and reprocessed ammonia support the operation of fuel cells that generate electricity. Some versions of new generation small-scale nuclear solve the problem of cooling reactors with high pressure water or high pressure helium. The widespread acceptance of nuclear-powered commercial ships depends on the assurance of the populations of the greater safety of contemporary nuclear technology.
Nuclear incidents such as Fukushima (Japan), Three Mile Island (United States) and Chernobyl (USSR – Russia) and the stockpile of semi-used nuclear fuel rods have generated strong public opposition to the expansion of the nuclear energy. While traditional nuclear reactors are cooled by water, helium gas pumped at high pressure cools some modern reactors at high temperatures. The structural failures of high pressure water or gas cooled reactors have catastrophic implications. Recent developments solve the pressure problem by cooling the reactor with a liquid metal that melts at just under 210 degrees F (98 degrees C) and remains liquid at 1470 degrees F (800 degrees C) at atmospheric pressure.
Another unique nuclear technology involves adding nuclear material to molten salt, which also solves the problems of cooling nuclear reactors with high pressure steam or gas. The molten salt nuclear material becomes liquid at about 750 deg F (400 deg C) and is solid below this temperature. Some developing nuclear technologies, notably molten salt variants, are capable of reprocessing semi-spent nuclear fuel. Any failure of the molten salt nuclear reactor would cause a drop in temperature and solidification of the molten salt nuclear fuel, thus improving its safety and propellability for commercial ships.
Energy conversion efficiency
The production of green hydrogen requires electrical energy to perform electrolysis, separating hydrogen from oxygen with a conversion efficiency of 65 to 75%. Solid oxide fuel cells convert hydrogen to electrical energy with an efficiency of 55-65%, with an overall energy conversion efficiency from electricity to electricity of about 45-50%. A nuclear power plant can generate electricity with an efficiency of 36% from the fuel rod to the transmission line, with a maximum overall efficiency of 18% from the power plant via the hydrogen and the fuel cell to the propeller of the ship. Nuclear power can be indirectly used to produce ammonia as well as methanol, with losses in energy conversion efficiency.
The direct production of nuclear energy on board a ship avoids the efficiency losses associated with the production of hydrogen, ammonia or methanol. While low-quality exhaust heat from land-based nuclear power plants can contribute to the production of methanol, energy is required to grow and harvest the crops necessary for the production of methanol. Direct use of nuclear energy for propulsion of commercial ships allows arable land to be used for food production to feed human populations, instead of cultivating crops to produce biofuel. Over the life of a ship, it would be possible for a nuclear powered ship to be competitive with other zero carbon technologies.
Ports and Suez Canal
Public pressure and security concerns have prompted many coastal cities internationally to ban nuclear-powered ships from entering ports. Currently, the Suez Canal Authority discourages nuclear powered ships from crossing the Suez Canal. It is only on very rare occasions and through intergovernmental negotiations that the Suez Canal Authority has authorized a nuclear powered vessel to transit through the canal. The threat of a breakdown occurring on a nuclear vessel while it was navigating the canal would result in the closure of the canal and a massive loss of revenue for the Canal Authority.
The Suez Canal Authority allows towed vessels to transit through the canal. There is usually prior notification and negotiations when a small vessel such as a tug towing a large vessel through the canal. On occasion, a large vessel has towed a much smaller vessel through the canal and such precedent provides a possible basis for future discussions and negotiations with the Suez Canal Authority. A future possibility would involve a small vessel producing electricity while being towed by a much larger vessel pulling a towing cable which also carries power cables.
A molten salt nuclear reactor could be deactivated before a nuclear-powered vessel arrives at the entrances to the Suez Canal, and a towed electric generator vessel would attach to each deactivated nuclear vessel via tow rope and electric cables interconnection, providing propulsive energy and navigation control. to the big ship. The electrical power of the towed small vessel would support the propulsion and navigation control of the large vessel. While such an operation is technically possible, it has never been operated through the Suez Canal and would require a political direction from the Suez Canal Authority.
On-board battery power supply
There is potential for battery technology to support low-speed propulsion and navigation of ships along the 120-mile Suez Canal. The same batteries would provide short-range propulsion and navigation control when nuclear-powered commercial vessels arrive and depart from ports that require the deactivation of molten salt reactors onboard every nuclear commercial vessel. Alternatively, port battery ships would connect via tow wire and interconnecting power cables to provide propulsive power and navigation to large nuclear-powered commercial vessels arriving and departing with molten salt reactors disabled.
Port authorities in several countries and the Suez Canal Authority should consider the future possibility of nuclear-powered commercial vessels arriving at the port and requesting transit through the Suez Canal. Port authorities and the Suez Canal Authority should be assured of the relative safety of molten salt nuclear technology compared to previous nuclear technology. All authorities would likely face public pressure to provide security at ports and along the Suez Canal. Shipping companies considering future large nuclear-powered container ships will need to negotiate with the Suez Canal Authority and port authorities internationally.
Plans are underway in South Korea to develop a commercial vessel powered by a molten salt nuclear reactor. This is one of the technological options as the international maritime industry shifts to low carbon, zero carbon propulsion. There will likely be future discussions with the Suez Canal Authority regarding nuclear powered commercial vessels requiring transit between the Mediterranean Sea and the Red Sea, as well as future discussions with port authorities at the international level.
The opinions expressed here are those of the author and not necessarily those of The Maritime Executive.