OXFORDSHIRE, England, June 12, 2007 -- The proposed European High Power Laser Energy Research (Hiper) facility -- a device intended to demonstrate the feasibility of laser-driven fusion as an energy source -- is entering the preparation phase after completion of a two-year study by an international team of scientists.
Their conclusions have allowed the Hiper project to be selected as part of the European roadmap for future large-scale science facilities. The preparatory phase of the Hiper facility is expected to begin in January and to last for three years.
Fifteen nations are now associated with Hiper. Involved at partner level are the Czech Republic, France, Greece, Italy, Portugal, Spain and the UK. The Conseil Régional d'Aquitaine (France) and the Comunidad Autonoma de Madrid (Spain) are involved at the regional government level. Institutions and scientists from Russia, Germany and Poland are directly involved in the project, and scientists from the US, Japan, China, South Korea and Canada are collaborating.
The proposed European High Power laser Energy Research (Hiper) facility (Image courtesy Rutherford Appleton Lab)
The team is comprised of 22 partners from the nations involved, including US General Atomics Inc., a private San Diego-based company that is looking into the commercial production of laser fusion targets. Lawrence Livermore National Laboratory, home of the National Ignition Facility (NIF), also has a strong link to the project.
Mike Dunne, director of the Central Laser Facility at Rutherford Appleton Laboratory -- a UK scientific research lab based in Oxfordshire, England, and a Hiper partner -- said the preparatory phase will be the basis of a decision to construct the facility by a consortium of nations and funding agencies. Endorsement by the European Commission (EC) is currently being assessed, as part of its Framework Programme 7. The results will be known this summer. (See: http://cordis.europa.eu/fp7/capacities/research-infrastructures_en.html)
A key goal of the EC in funding these projects, Dunne said, is deciding who will host the facility.
A recent BBC story said UK funding bodies, including the Science and Technology Facilities Council that own and operate most of the UK's large science instruments, are making "positive noises about stumping up the necessary cash to build and host Hiper in the UK."
Dunne said the host nation normally commits the greatest share of the construction and operation costs, so decisions on hosting are closely tied to decisions on financing. "In essence, the UK funding for civilian science comes through the Office of Science and Innovation (part of the Department of Trade and Industry). This runs a number of research councils, of which the Science and Technology Facilities Council (STFC) is one. STFC takes the lead role for large physics facilities."
Mike Dunne, director of the Central Laser Facility at Rutherford Appleton Laboratory (Photo courtesy Rutherford Appleton Lab)
In October 2006, the countries of Europe published a joint "roadmap" for future science facilities which was driven by the European Strategy Forum on Research Infrastructures, or ESFRI.
"The point of the European roadmap and the corresponding European Commission 'preparatory phase' projects is to provide a coordinated mechanism to allow the various European countries to determine a balanced set of priorities for future science facilities," Dunne said. "By preparing a roadmap, the countries can see a portfolio of science opportunities and so discuss the degree to which each country wants to participate in each project. This is expected to lead to a far more balanced set of science facilities across Europe than would otherwise be the case."
Like the Hiper project, fusion energy's promise is farsighted. "Fusion offers the potential for energy production at a scale that meets the long-term demand from mankind," Dunne said. "Nuclear fission is clearly a major power source at the moment, and is likely to be so for many decades to come, given that it doesn't release any greenhouse gases."
However, since there is only a finite amount of fission fuel on the planet, more advanced techniques are needed for the longer term. "There are advanced methods of fission (called Generation 4 reactors), and of course there is fusion. The reality is that there's likely to be a mixture of advanced fuel sources by the middle of the century. From a power supply viewpoint this is a good thing, as it minimizes any risk to delivery by avoiding single points of failure."
Achieving nuclear fusion using lasers is the goal of the National Ignition Facility, the latest in a series of high-power laser facilities used for research in inertial confinement fusion. Now under construction at the Lawrence Livermore National Laboratory, in Livermore, Calif., NIF is being built by the US Department of Energy as part of its Stockpile Stewardship program, and as such has a strong defense mission. "This is largely due to the fact that NIF converts its laser light to x-rays, and those x-rays are then used to implode the pellet (or perform other, classified experiments)," Dunne said. "This is meant to be analogous to the use of x-rays in thermonuclear weapons."
Hiper removes this link to defense science, Dunne said. "It uses the optical laser light directly to drive the implosion and initiate fusion. The physics associated with the interactions of lasers with matter have no relevance whatsoever to nuclear weapons, so we see this as very much a 'swords into ploughshares' undertaking."
NIF will demonstrate net production of energy from fusion. Hiper is designed to take this forward in a way that is compatible with a power-generation goal, he said. "We have very good working relations with the NIF team, and they also have plans for research into fast ignition for the future, once they succeed with their primary mission."
Construction of the NIF is currently estimated to be completed in 2009, with the first fusion ignition tests planned for 2010. "This will demonstrate a factor ~20 times more energy from fusion than was delivered by the laser," Dunne said.
Hiper aims to use a more efficient technique, a variant of inertial fusion called fast ignition. The physics of fast ignition is less certain, so it is being studied in a series of experiments in Europe, the US and Japan over the next three years. The success of these experiments will determine whether Hiper should be built, Dunne said. "More properly, they will determine the size that Hiper needs to be."
Since Hiper will be based on demonstrated experimental results on precursor laser systems, it has a "very high likelihood" of success, he said.
"Nuclear fusion energy production from lasers uses a technique known as inertial fusion," Dunne said. This technique was proven, he said -- emphasizing "proven" -- in the 1980s using an intense x-ray source under the Nevada desert in an experiment carried out by the Lawrence Livermore National Laboratory that is still highly classified.
There are basically four obstacles to laser fusion as a power-generation source, Dunne said:
Proving the physics of laser fusion energy production. "This has largely been achieved in the 1980s, with the final confirmatory experiment planned on the NIF for 2010. In this regard, laser fusion is far in advance of magnetic fusion." Given that the project is in the R&D stages, Dunne said, any opposition to Hiper is now in the realm of scientific critique, "which of course is absolutely necessary and highly productive," but there are two common objections: "The first is along the lines of, 'This may be a long-term solution, but the world has an immediate term problem to solve, so this is an unwanted distraction.'"
Building a laser that can fire sufficiently quickly (~5 times a second) and with sufficient efficiency (~10-20 percent) at the scale required for fusion (~10 kJ beams combined together to deliver ~1 MJ). "Such a laser does not exist today, but a simple glance at the rate of progression of lasers will show that such performance is likely to be achieved before 2020 -- easily in time for a laser fusion reactor."
Manufacturing the laser fusion pellets which contain the fuel sufficiently cheaply that the energy is commercially viable. "This means much less than a dollar per pellet, which is much cheaper than at present. I believe this is the most difficult problem to overcome, and will almost certainly need a change in technology to deliver it. An example may be the use of semiconductor microelectromechanical systems (MEMS) technology." Industry and academia are working together on this problem, he said.
Designing an integrated reactor that combines all the elements together in a suitably efficient and robust manner. "This is a difficult problem, but a number of conceptual designs exist, and I have every expectation that a number of good solutions will be produced over the next 10 years. Magnetic fusion schemes are far more advanced in their integration than laser schemes. The laser schemes allow the problem to be split apart (to "divide and conquer"), which is a great benefit, but means that we are not forced to produce an integrated reactor design until we need one."
Dunne said, "I would not disagree with the need to solve the immediate-term problem, but we need to make sure we never get ourselves in this type of position again. We need to ensure we have a long-term supply of clean energy, with high security and of a scale that can meet the demand."
The second objection, he said, is typically: "Why do we need Hiper when we have Iter? Surely this will just dilute the funding required for Iter?" Iter (International Thermonuclear Experimental Reactor) is a joint international research and development project that aims to demonstrate the scientific and technical feasibility of fusion power. The partners in the project -- the Iter Parties -- are the European Union (represented by The European Atomic Energy Community, or Euratom), Japan, the People´s Republic of China, India, the Republic of Korea, the Russian Federation and the US. Iter will be constructed in Europe, at Cadarache in southern France.
Dunne's answer: "At the moment, this is a false argument, as the two are funded from entirely separate sources, with Hiper in the R&D phase, but Iter in the demonstration phase. Over the longer term, the argument still fails to hold water, because the scale of the problem is such that it demands multiple solutions -- both to minimize any risk to the final delivery and to ensure that there is a balanced portfolio of energy solutions, just as there is with conventional fuels: with gas, coal, oil, etc., and as there is with renewables -- wind, wave, solar, tidal, etc."
As far as potential risks, he said, "The beauty of fusion is that the risks are truly very low. There are no long-lived radioactive products, and of course no greenhouse gases. Also, a laser fusion reactor will contain only a very small amount of fuel (milligrams) at any one time, so there is no stored energy, so no chance of meltdown; and in the event of a disaster -- accidental or otherwise -- there is only a small amount of fuel released. Extensive environmental studies have shown that such accidents are readily manageable."
Dunne added, "It must be remembered that Hiper is being designed as a flexible science facility to undertake a wide variety of fundamental physics research. Laser fusion is the most demanding, and as such has defined Hiper's specification. We believe that a marriage of fundamental science with a strong societal goal is absolutely the way forward for any major project of this type."
For more information, visit: www.hiper-laser.org
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