The physics problems remaining to be solved to achieve practical fusion power by magnetic confinement techniques are believed to be well posed and soluble. A programme plan recently developed in the United States calls for progressively larger plasma confinement experiments to address these physics questions in line with a serious programme in fusion power engineering. Implementation of the plan is expected to lead to the first production of power from a deuterium–tritium-fuelled system in 1980. Thereafter, three progressively larger experimental electrical power reactors are planned, leading to fusion power commercialization in the later 1990s.
The environmental characteristics of fusion reactors have been estimated by analyzing conceptual reactor designs. It is projected that the only volatile radioactive material in a fusion power-plant will be the tritium fuel. Analyses indicate that tritium leakage can be held to very low levels and accordingly should not pose a significant environmental hazard.
Careful selection of the materials of construction of a fusion reactor core will minimize radioactivity induced by neutron activation. This activity will be nonvolatile, and it can be isolated from the environment by the use of existing techniques. Because this induced activity is short-lived, it does not represent a long-term storage problem.
Anticipated thermal efficiencies of fusion powerplants range from present-day levels (30–40%) using standard conversion systems to about 50% when more exotic techniques (such as liquid-metal topping cycles) are utilized.