Nuclear Fusion
Will Fusion Power ever work?
Nuclear Fusion is often presented as the Holy Grail of electricity production. This website shows why building a fusion power plant is very difficult to achieve and may never become a reality.
Immense Challenges for Nuclear Fusion Reactors
The many immense challenges for tokamak fusion power plants using deuterium-tritium fuel are presented. Some of the problems discussed for commercial fusion may be insurmountable.
Essentials of Nuclear Physics
A basic knowledge of nuclear physics is required to properly understand the issues related to the generation of electricity from nuclear reactions.
Essentials of Plasma Physics
Understanding the technology of controlled fusion requires some knowledge of the plasma physics involved.
Nuclear Fusion and Nuclear Fission
Two possibilities for nuclear power generation exist: fission, and fusion. Features of the two methods are compared showing exaggerations in the advantages claimed by fusion advocates.
Reactor Costs, Fusion compared to Fission
The cost of fusion, relative to other electricity sources, will be the primary decider for commercial power. Estimates are presented, concluding that fusion is likely to cost 10 times more than fission.
Radioactive Waste
The neutrons from fusion reactions make certain materials radioactive via neutron activation. This will produce large volumes of radioactive waste which must be managed for hundreds or even thousands of years.
Materials and Radiation Damage
The materials in a reactor must survive damage from the enormous flux of neutrons emitted from the fusion reactions. This problem is as yet unsolved and with current materials reactor components will have to be replaced on a regular basis.
Safety of fusion compared to fission
Safety is often evoked to suggest that fusion is preferable to fission, but many risks exist for fusion reactors which are similar to those of fission reactors. A major risk for both, is loss of coolant followed by hydrogen explosions.
Lack of Tritium Fuel Supply
Tritium is scarce in nature and all tritium supplies come from CANDU fission reactors. In a few decades, these reactors may stop operations and the global supply of tritium could be close to zero before commercial fusion power plants are in operation.
Tokamak Fusion Reactors
Most efforts towards fusion power rely on magnetic confinement with tokamaks and ITER is the latest such device in construction. It is planned to be followed with demonstration power plants before the final achievement of commercial fusion power.
Breeder Blanket
The Breeder Blanket is the most critical and complicated component of a fusion reactor because of the dual functions of heat extraction and tritium breeding.
Divertor and Limiter
The divertor is the device which implements the exhaust of the plasma at the end on a confinement cycle. The limiter scraps the edge off the plasma in disruptions. These components have the highest radiation damage in the tokamak.
Superconducting Magnets
Superconducting magnets are the core enabling technology for magnetic confinement fusion reactors. The reliability of the magnets is essential for the operation of a fusion power plant.
Maintenance, Breakdowns and Availability
Because of the system complexity, the time a fusion power plant is fully operational to produce electricity could be low. The fusion reactor availability will be reduced by necessary scheduled maintenance as well as component breakdowns.
Pharaonic Size and Byzantine Complexity
The enormous physical size of the ITER tokamak, and the complexity of the associated systems required for operations, raise serious doubts that commercial reactors of even bigger scale could ever be viable.
Essential Test Facilities
The development of materials and tritium breeder blankets for fusion reactors is essential. This requires dedicated test facilities providing a flux of neutrons similar to that of an operational fusion reactor. No such facilities are, as yet, in operation.
Timescales advertised for Commercial Fusion Power Plant
After ITER, plans diverge around the world for arriving at commercial fusion power. Schedules for the construction of mainstream fusion power plants are presented.
Show-Stoppers for Mainstream Approach
The mainstream approach toward commercial fusion reactor has major "show-stoppers". This page summarizes problems discussed throughout this website.
Alternatives to Mainstream Fusion
The chances of mainstream fusion ever leading to large scale commercial power plants is low. This page explores the alternative technologies.
Compact Tokamaks
The big problem for mainstream fusion is the enormous size required for a power plant. New projects propose compact toroidal devices with high temperature superconducting magnets which allow higher magnetic fields and so higher plasma density.
Stellarators
Stellarators are perhaps the most promising alternative fusion devices to mainstream fusion tokamaks with the possibility for steady state operation and no danger from damage from plasma loss in disruptions.
Inertial Confinement Fusion
The inertial confinement fusion technology has competed with the mainstream methods since the beginning of nuclear fusion research. The method temporarily confines the fusing plasma with the inertia of a surrounding material. In the past laser implosion has been used but other methods are now being developed.
Aneutronic Fusion
The emission of neutrons is an intrinsic disadvantage for mainstream fusion with Deuterium-Tritium fuel. Some projects propose to avoid this by the use of "aneutronic fuel" like proton-Boron11 and Deuterium-Helium3.
Spherical Tokamaks
The Spherical Tokamak has advantages over a conventional tokamak because of a more compact shape which gives a more efficient plasma with improved stability.
Why bother with Fusion rather than Fission?
Fusion power only really makes sense if it has clear advantages over fission power. Fusion advocates claim this is the case, but this page summarizes the arguments that fusion has, in fact, no significant advantages over fission.
Commercial Fusion will likely never Happen
The final conclusion of this website is that nuclear fusion commercial reactors will never be competitive with nuclear fission reactors. For this and other reasons commercial fusion reactors will never come into service.