DDAS Visit to the Culham Centre for Fusion Energy in Oxfordshire - Saturday 20th May 2017
Article by Mike Lancaster
How do you build a star on Earth? On Saturday 20th May 2017 a group of 12 DDAS members headed down to Culham in Oxfordshire to find out. It might be usual for astronomical societies to visit observatories, and places of space and astronomy research etc., and indeed looking through our past trips on this website that has been the case. But on this occasion our secretary Brian Dodson had arranged something a little bit different. We were not disappointed. Awe struck would be good term. Fusion is the process that powers the stars including our own Sun. Nature has done this trillions of times across the universe but to our own species this presents something of a challenge. We've already done it in the apocalyptic power of the H-bomb but to release this source of energy in a sustained and peaceful fashion to provide power for the grid is something else entirely. As science presenter Brian Cox has said, it would be a 'get out of jail card' for the future of our energy needs.
In short as we were reminded at Culham, fusion has the following benefits:
Essentially limitless fuel
No greenhouse gases
Major accidents impossible
No long-lived radioactive waste
Could be a reality in 30 years
Our day began with 2 hours of fossil fuel burning from Derby to Abingdon on the south side of Oxford, where we stopped off at The Spread Eagle pub for an excellent lunch. Having replenished our own energy levels we drove over to the Culham Centre for Fusion Energy, which is operated by the UK Atomic Energy Authority. This was in fact an open day and we were one of four groups touring the site this afternoon. After receiving our security passes at the main gate we headed over to the centre itself where after tea and biscuits we were given a lecture on fusion energy and the work being carried out at Culham. The centre operates two main experiments - MAST (Mega Amp Spherical Tokamak) and JET (Joint European Torus).
Following the talk the four groups split up to tour the facility and the DDAS party were taken to see the MAST experiment (Mega Amp Spherical Tokamak). A tokamak is a device that uses a powerful magnetic field to confine plasma in the shape of a torus. The tokamak is one of several types of magnetic confinement devices being developed to contain the hot plasma needed for producing controlled thermonuclear fusion power. MAST uses a spherical shaped containment vessel rather than the more conventional torus used by JET, and is one of the world's two leading spherical tokamaks (the other being at Princeton in the USA). We were shown around MAST by a very enthusiastic and enganging scientist. Having originally begun operating in 1999 the device is currently undergoing a major upgrade (MAST-U). It is designed to study the physics of plasmas and investigate the potential of the spherical tokamak route to fusion power. In particular the results from MAST-U will be used to shape the design of ITER (International Thermonuclear Experimental Reactor), the next generation of fusion reactor being built in the south of France. Our guide showed us video footage of the plasma inside MAST and the site of what will become the MAST-U control centre. Next we got up close to MAST itself before being shown a number of components from it, and also a scale model of the device.
Following our tour of MAST we headed over to the viewing gallery by the control room of the Joint European Torus (JET). We viewed footage of previous experiment runs or 'pulses' of JET and our guide explained a little of what goes on in the control room. Today however all was quiet with the device shut down and the control room empty except for a lone engineer keeping an eye on things. JET has been in operation since 1983. It is the world's largest and most powerful tokamak and holds the world record for fusion power of 16 mega-watts, which it attained in 1997. After viewing the control room we were given a more detailed overview of how JET works and its place in fusion research. Like MAST it is also very much involved in testing the physics and engineering to be used for ITER. Suitably briefed we donned hard hats and headed over to the JET building for an encounter with the machine itself. First off we viewed a test rig version of JET which is not a working device but it is used to test equipment and concepts before installation on the real thing. Then we were privileged to be allowed access to the holy of holies itself, which members of the public do not often get the chance of doing, as currently the device was fully powered down.
After having toured JET we returned to the reception area where we had a chance for further refreshments, to purchase souvenirs and to chat to the enthusiastic staff a while longer. I must admit that despite all the troubles we are facing in the world today to feeling a great sense of optimism after visiting CCFE. The future can be bright if we so choose. The future is fusion.
Our thanks go to CCFE and especially our guides for the excellent tour they gave us, and for giving up a Saturday afternoon to do so! Also many thanks to DDAS secretary Brian Dodson for organising an enthralling day out.