Fusion has the potential to become one of the long term options for the supply of electrical energy with a moderate impact on the environment. This is particularly important for Europe because of our comparatively scarce natural resources, our high population density, and our dependence on large-scale industrial production.The European approach to the development of fusion is by toroidal magnetic confinement: Tokamaks as the main line, and Stellarators and Reversed Field Pinches as alternatives. The results achieved in the Joint European Torus (JET) and other European Tokamaks have put Europe in the frontline of worldwide fusion research. The plasmas produced in JET are now less than a factor 2 from break-even and only 7 from ignition. Promising steps towards controlling the impurities have been made.In parallel to the efforts in plasma physics, the NET (Next European Torus)-team and a substantial technology programme are now in place. This will prepare the ground for the Next Step device, conceived as an experimental Tokamak test reactor. The programme includes plasma facing components, superconducting magnets, the fuel system, remote handling equipment, nuclear components such as the shielding blanket, completion of the data base on structural and insulating materials, and the assessment of the safety and environmental impact of the Next Step. In addition, R&D on the breeding blanket and on advanced materials are targeting the demonstration power reactor.The workplan for the next five years will take in due consideration the recommendations of the Fusion Review Board which has just completed an assessment of the European Fusion Programme. This workplan is likely to include a major effort to control plasma purity in an extended operational period of JET; expanding the physics and technology effort towards the Next Step; initiating the engineering design of the Next Step; pursuing investigation of the reactor potential of alternative lines; strengthening the long-term research in materials and other areas affecting the environmental, safety related and economic potential of fusion; undertaking conceptual design studies of a commercial reactor.Based on the very positive experience in international cooperation, particularly with the United States of America, the Union of Soviet Socialist Republics, Japan and Canada, there are good prospects for the Engineering Design of the Next Step to be undertaken in the frame of an International Thermonuclear Experimental Reactor (ITER).

1 Long-term objective of the Programme

By decision of the Council of Ministers of the European Communities the ‘Community Fusion Programme is a long-term cooperative project embracing all the work carried out in the Member States (plus Sweden and Switzerland) in the field of controlled thermonuclear fusion. It is design to lead in due course to the joint construction of prototype reactors’.

2 Medium term objectives

The main medium term objective of the Programme is a Next Step Tokamak which, firstly, should complete the demonstration of the scientific feasibility of fusion by achieving both ignition and the control of a burning D–T plasma during long pulses in reactor-relevant conditions and, secondly, should address substantial technological issues of reactor relevance. The Next Step should be designed and constructed as soon as technically possible, preferably in an international framework (International Thermonuclear Experimental Reactor, ITER), or alternatively in a European frame (Next European Torus, NET).

Other objectives are to develop the environmental, safety-related and economic potential of fusion power, to continue investigating the reactor potential of Stellarators and Reversed Field Pinches, to maintain a ‘keep-in-touch’ activity in inertial confinement, to expand the involvement of European industry, and to extend the scope of international collaboration.

3 Achievements and future planning

The performance of Tokamaks in the European Community (EC), Japan, the United States of America (USA) and the Union of Soviet Socialist Republics (USSR) are illustrated in fig. 1. The product of the ion density, energy confinement time and ion temperature, called fusion product, is a figure of merit; its dependence on plasma temperature allows a comparison of the achievements with reactor requirements. As shown in this figure the Joint European Torus (JET) which is the European Community’s most important fusion device and the world’s largest tokamak has reached excellent results. First plasma was obtained in 1983 in JET, now up to 35 MW of additional heating power are applied at plasma currents up to 7 MA, and long pulses of up to 30 s were obtained at plasma currents of about 3 MA. Best plasma performances today give plasma temperatures of up to 25 keV and fusion products of about 9 × 1020 m−3 keV s, that is only less than a factor of 2 from break-even and about a factor of 7 short of ignition. To fully exploit the JET device an upgrading is foreseen where the heating power will reach about 50 MW, and a pumped divertor is proposed to be installed. D–T operation is planned for the last two years of JET operation in 1995–96.

Figure 2 indicates the planned modifications and the working programme to be implemented in the new phase of JET. Of particular importance will be the optimisation in X-point configuration and Next Step oriented studies with a pumped divertor and the tritium operation.

The European Fusion Programme possesses also a unique ensemble of specialised Tokamaks whose main objectives and characteristics are listed in table 1.

With regard to alternative lines, several devices are under construction or in operation: the modular Stellarator WENDELSTEIN VII-AS has started operation, the Reversed Field Pinch RFX, presently under construction, will become operational in 1991, and the construction of the flexible heliac device TJ-II is starting. A large modular advanced Stellarator, WENDELSTEIN VII-X, is in the pre-design phase.

The Fusion Technology effort is directed towards three main issues: (a) the Next Step Technology, being understood that the Next Step shall adopt those reactor technologies which have reached an advanced stage of development; (b) the Blanket Technology, as one of the objectives of the Next Step is to test components, such as blanket modules in reactor-like conditions; and (c) the Long-Term Technology, addressing materials R&D and strategic issues.

As regards the Next Step, the Community Programme is expected to provide by 1996 the scientific database necessary to start the construction of a Next Step based on the technological solutions available by that time in the areas of plasma facing components, superconducting magnets, fuel cycle (tritium), remote handling, shielding, and safety and environment. Long burn pulses (~ 700 s) as envisaged for the Next Step are feasible in reactor-relevant conditions by means of inductive current drive only. Considering a tritium consumption of about 7 grams/hour an integrated burn time of a few thousand hours appears to be conceivable without breeding blanket.

A comparison between the purely European Next Step NET and the quadripartite (Euratom, Japan, USA, USSR) Next Step ITER is given in table 2. The main differences between NET and ITER are related to non-inductive current drive and the breeding blanket. Non-inductive current drive is...