When someone talks of fusion energy, an old joke about the sci-fi power source quickly rears its head. Fusion, say skeptical wags, is the energy of the future and always will be.
While this largely has been an apt description of fusion research since the dawn of the nuclear age, two major research projects on opposite sides of the Atlantic are coming closer than ever to making fusion power a reality.
Put simply, fusion is the process that takes places at the center of stars – including our own sun. Under the tremendous pressure of the gravity of a stellar mass, atoms at the core of a star are pressed so densely together that they literally fuse into different elements. In our own sun, every second uncountable numbers of hydrogen atoms are fused together to create helium – releasing tremendous amounts of energy in the forms of heat, light and radiation that eventually reaches us here on Earth.
Here on Earth, humans can recreate this process via nuclear hydrogen bombs, which initially use fission – fusion’s opposite process of splitting atoms apart to release energy – as a starting point. This is done by focusing the energy released by an atomic, fission-based explosion onto thermonuclear fuel – usually some isotope of hydrogen – that is typically housed directly behind the primary atomic device in a thermonuclear bomb. The focusing of the fission explosion creates the tremendous pressures needed to fuse the fuel and so release energy in an uncontrolled thermonuclear reaction similar to that found in the sun.
This technique for creating fusion energy, which was first theoretically discussed in 1941 by physicists involved in the U.S. Manhattan Project, was put into practice in the 1951 when an experimental bomb test showed a fusion-based, thermonuclear explosion was possible. This was followed in 1952 by a full-scale test – the famous Ivy-Mike tests – which incinerated Enewetak Atoll through the release of some ten megatons (millions of equivalent tons of TNT) worth of explosive power.
By way of comparison, the atomic bombs that devastated Hiroshima and Nagasaki had yields of 16 and 21 kilotons (thousands of equivalent tons of TNT), respectively.
Here comes the sun
Thus, as far back as the early 1950s fusion energy was something with which physics was familiar. However, unlike a controlled fission reaction – which mankind had mastered in 1942 as part the wartime quest to produce an atomic bomb – a controlled fusion reaction remained permanently out of reach, in large part due to the tremendous energies needed to create and sustain it.
While disappointing, the fact is that, for humans, it literally takes the energy released by an atomic bomb to replicate the stellar conditions required to produce fusion – and for decades the knowledge, both theoretical and practical, necessary to control such a reaction was, like the heavens where the sun hangs, seemingly out of reach.
But the dream of fusion would not die — for obvious reasons. Whereas fission-based reactors create nuclear waste or bomb-grade material, are hideously expensive and are prone to devastating accidents and meltdowns that can release deadly amounts of radiation, a controlled fusion reaction theoretically has none of these problems. If mastered, fusion could potentially power the planet on abundant fuel – deuterium, the most likely isotope to be used, is abundant in the Earth’s oceans – for thousands of years. Finally, while commercial power so created might not be “too cheap to meter,” it would nonetheless be completely carbon free and produce vastly more power than a similarly-sized fission reactor.
Where’s the Cold War when you need it?
So motivated by visions of clean, near-limitless amounts of fusion energy, research by all the major scientific powers continued with varying degrees of urgency ever since. Today, it has resulted in two primary theoretical approaches that are now being developed in Europe and the United States. In Europe, the latest iteration of what is known as the magnetic containment approach to a controlled fusion reaction is taking shape under the auspices of the International Thermonuclear Experimental Reactor (ITER) project, which is now building a reactor complex in Southern France.
This massive, international project began in 2007 and is based on a reactor design originally proposed by Soviet scientists during the Cold War. The basic idea is that superheated hydrogen gas – again, deuterium – is imprisoned within extremely powerful, specially calibrated magnetic fields. The plasma, as this superheated gas is known, is then compressed by the magnetic field to the point where fusion begins to take place – releasing energy in the form of heat in the process. While no full-scale reactor based on the Soviet design has ever been built, the design has shown good experimental results in low-power reactors since at least the late 1960s.
The trick to magnetic confinement is containing the tremendous energy of the heated plasma within a magnetic field strong and supple enough to withstand the forces emanating from within. If the magnetic field fails in some way, then the pressure needed to fuse atoms will not be created and fusion, like steam seeping out of a pressure cooker, will quickly fizzle. The ITER project, the summation of current magnetic containment research, hopes that by leveraging enough computer power to successfully model field-plasma interactions and by also scaling up energy input into the initial reaction, it can create – at admittedly tremendous initial financial cost – a controlled, self-sustaining fusion reaction capable of producing power at commercially-viable levels, at least when calculated over long periods of time.
It’s a (laser-filled) party in the U.S.A.
While the United States has contributed a great deal to ITER – approximately 10 percent of the entire cost of the project – the U.S. has also developed a homegrown, controlled fusion project that is based on an entirely different method, known as inertial containment. This project, based at the National Ignition Facility (NIF) at the Lawrence Livermore National Laboratory in central California, uses high-powered lasers to zap a hydrogen fuel pellet with enough focused energy to crush it, causing it to implode and so causing fusion to occur in the process.
The key difference with the ITER method is that whereas the plasma contained by a magnetic field is always burning and thus always “on,” laser-powered inertial containment acts more like an internal combustion engine, wherein each laser blast creates the power necessary to produce the next pellet-crushing, fusion-producing laser pulse. The reactor and the tremendous forces that create fusion are thus not always “on” as in magnetic containment, but is instead intermittent. In theory, this intermittency should make a controlled fusion reaction less complex and thus less costly to pull off.
Indeed, early tests of the concept, which originated out of top-secret nuclear weapons modeling projects sponsored by the U.S. Department of Energy, showed enough early promise that a full-scale inertial containment laser device was ordered to be built at Lawrence Livermore in 1997, even as the parallel ITER project began to coalesce and move forward. The result was the NIF, which began testing in June of 2009 after a decade spent constructing the lasers and the facility housing them. The ITER reactor, in contrast, has not even been built yet, though the first of its components are just now beginning to arrive on site and construction has at long last finally begun.
No budget for bottling the sun
Thus stands the status of the two major approaches we have so far devised to place the sun in a bottle. There are other approaches and research projects, of course, but none have reached the point where large-scale experimental reactors have been built or are under construction, and as a result these alternative routes to fusion power remain much more theoretical in scope. They, too, deserve and receive funding, but at present we have placed our immediate scientific chips on ITER’s magnetic containment and laser fusion at the NIF. With success in no way guaranteed, and with funding limited and always under the gun, the pressure on all those involved to produce results mimics fusion itself.
Austerity politics in both the United States and Europe have only ratcheted up the stakes for both projects, and testing setbacks in 2012 at NIF – which failed to produce fusion under a full-power test of the facility’s laser-pulse mechanism – and ITER’s huge cost and ponderous pace have raised concern in Washington that both efforts need to be scaled back – or at least the U.S. taxpayer’s contribution should be. As result, NIF’s 2014 funding has been reduced by some 16 percent – some $60 million – and the DoE has been forced to cut other promising avenues of fusion research in order to keep up with U.S. commitments on the ITER project.
Furthermore, the idiocy that is financial sequestration along with the general reduction in funds going towards basic scientific research that has been implemented by both the states and the federal government over the years are finally beginning to bite. The science behind fusion research, like other visionary “Big Science” projects, requires long-term, stable investments in technology and personnel of the scale that government has traditionally provided because private industry simply cannot. With our politics now as polarized as ITER’s would-be magnetic fields, this vital function of government, once taken for granted, is now in serious doubt.
A penny wise but a pound foolish
When one considers the folly of what we are doing – cutting funding to basic science and crucial proof-of-concept projects like NIF and ITER even as we continue to fund Pentagon boondoggles like wars in the Middle East, the F-35 fighter or the littoral combat ship – one weeps for the future. None of these military programs hold as much promise for a more prosperous and secure America than fusion, and all are far, far more individually expensive than all major fusion research projects combined.
Allowing sequestration and the Molochs in the military-industrial complex to devour fusion research funding would thus be a mistake of epic proportions. Such funding is a small portion of the overall federal budget and holds tremendous promise even if both ITER and NIF are ultimately unsuccessful, with rewards incalculable if they are.
Given the upside, it’s sad to think that just as full-scale fusion experimentation is getting going both here and in Europe, Washington might pull the plug out of a false concern for fiscal discipline and a misplaced sense of national priorities. If that happens, future historians will look back and, once controlled fusion is finally achieved, remark that what held back American leadership during this crucial period was not science or engineering — which will both surely be mastered someday — but a timidity of vision and a constrained sense of possibility that only a country in decline like ours could sustain.
The views expressed in this article are the author’s own and do not necessarily reflect Mint Press News editorial policy.