The Future is Fusion: Surpassing the “Break-Even” Point

JET_fusionreactorFor decades, scientists have dreamed of the day when cold fusion – and the clean, infinite energy it promises – could be made possible. And in recent years, many positive strides have been taken in that direction, to the point where scientists are now able to “break-even”. What this means is, it has become the norm for research labs to be able to produce as much energy from a cold fusion reaction as it takes in triggering that reaction in the first place.

And now, the world’s best fusion reactor – located in Oxfordshire, Engand – will become the first fusion power experiment to attempt to surpass it. This experiment, known as the Joint European Torus (JET), has held the world record for fusion reactor efficiency since 1997. If JET can reach break-even point, there’s a very good chance that the massive International Thermonuclear Experimental Reactor (ITER) currently being built in France will be able to finally achieve the dream of self-sustaining fusion. 

NASA_fusionchamber

Originally built in 1983, the JET project was conceived by the European Community (precursor to the EU) as a means of making fusion power a reality. After being unveiled the following year at a former Royal Navy airfield near Culham in Oxfordshire, with Queen Elizabeth II herself in attendance, experiments began on triggering a cold fusion reaction. By 1997, 16 megawatts of fusion power were produced from an input power of 24 megawatts, for a fusion energy gain factor of around 0.7.

Since that time, no one else has come close. The National Ignition Facility – the only other “large gain” fusion experiment on the planet, located in California – recently claimed to have broken the break-even point with their  laser-powered process. However, these claims are apparently mitigated by the fact that their 500 terrawat process (that’s 500 trillion watts!) is highly inefficient when compared to what is being used in Europe.

NIF Livermore July 2008Currently, there are two competing approaches for the artificial creation of nuclear fusion. Whereas the NIF uses “inertial confinement” – which uses lasers to create enough heat and pressure to trigger nuclear fusion – the JET project uses a process known as “magnetic confinement”. This process, where deuterium and tritium fuel are fused within a doughnut-shaped device (a tokamak) and the resulting thermal and electrical energy that is released provides power.

Of the two, magnetic confinement is usually considered a better prospect for the limitless production of clean energy, and this is the process the 500-megawatt ITER fusion reactor once its up and running. And while JET itself is a fairly low-power experiment (38 megawatts), it’s still very exciting because it’s essentially a small-scale prototype of the larger ITER. For instance, JET has been upgraded in the past few years with features that are part of the ITER design.

fusion_energyThese include a wall of solid beryllium that can withstand being bombarded by ultra-high-energy neutrons and temperatures in excess of 200 million degrees. This is a key part of achieving a sustained fusion reaction, which requires that a wall is in place to bounce all the hot neutrons created by the fusion of deuterium and tritium back into the reaction, rather than letting them escape. With this new wall in place, the scientists at JET are preparing to pump up the reaction and pray that more energy is created.

Here’s hoping they are successful! As it stands, there are still many who feel that fusion is a pipe-dream, and not just because previous experiments that claimed success turned out to be hoaxes. With so much riding on humanity’s ability to find a clean, alternative energy source, the prospects of a breakthrough do seem like the stuff of dreams. I sincerely hope those dreams become a reality within my own lifetime…

Sources: extremetech.com, (2)