The UK Independent reports that the Iter fusion project gained final approval “ for the design of the most technically challenging component – the fusion reactor’s “blanket” that will handle the super-heated nuclear fuel.”
The Iter project is designed to produce at a rate of 500 megawatts of energy using an input of 50 megawatts during a 1000 seconds run. The Iter fusion project is forecast to cost £ 13billion (US $20 billion) . The project team is an international combine of 46 nations that are contributing science and money. The facility is based in Cadarache, France.
Below is a cut-away of the Iter reactor design and brief description of the elements of the reactor from Howstuffworks.com
Magnetic Confinement: The ITER Example
The main parts of the ITER tokamak reactor are:
• Vacuum vessel – holds the plasma and keeps the reaction chamber in a vacuum
• Neutral beam injector (ion cyclotron system) – injects particle beams from the accelerator into the plasma to help heat the plasma to critical temperature
• Magnetic field coils (poloidal, toroidal) – super-conducting magnets that confine, shape and contain the plasma using magnetic fields
• Transformers/Central solenoid – supply electricity to the magnetic field coils
• Cooling equipment (crostat, cryopump) – cool the magnets
• Blanket modules – made of lithium; absorb heat and high-energy neutrons from the fusion reaction
• Divertors – exhaust the helium products of the fusion reaction
Reuters provides an simplified description of the fusion process in the chart below
The temperatures are extraordinary to say the least. The Sun’s energy is produced by fusion of hydrogen to helium. The Iter will mimic that reaction but at temperatures at least 10 times higher than the temperature at the Sun’s core. The higher temperature is necessary because the force to drive the molecules of hydrogen together in the Sun is partially accomplished by the Sun’s core pressure said to be about 1X 10ˆ8th atmospheres. The tokomak fusion takes place in a vacuum.
From the Independent posting:
“Richard Pitts, a British nuclear physicist working on the project, said that even though Iter has a nuclear operator’s licence and will produce about 10 times as much power as it consumes, the Iter machine will still remain a purely experimental reactor, with no electricity generated for the French national grid. “We’re not building a demonstration industrial reactor. We’re building the first step towards one that does produce electricity for the grid. If we can show that fusion works, a demonstration reactor will be much cheaper to build than Iter,” Dr Pitts said.
A working industrial reactor, is not forecast to go into operation until somewhere around the decade of 2050. The electricity production method at that time would function as shown in this simplified schematic from Howstuffworks.com which is pretty much the way, with the exception of the fusion reactor, all electrical energy is created.
An abbreviated Project schedule is as follow:
2021-22: “First plasma” scheduled, when ionised gases will be injected into the Iter tokamak.
2027-28: Iter “goes nuclear” with injection of tritium.
2030s: First demonstration fusion reactor to produce electricity for grid.
2050s onwards: First commercial nuclear fusion power plants.
The attempts to harness fusion have been going on for many decades. The US followed several paths but seems to have bet their money on laser beams to initiate fusion. This research continues and perhaps it is mainly driven by NASA’s need for small-scale fusion reactors for powering deep-space rockets.
The Joint European Torus holds the fusion reactor performance record when the fusion energy produced was a peak of 16 MW for less than a second. Quite a long way to go to get the results the Iter is aiming for.