Nuclear Fusion

The perception of the energy problem in Germany is surprisingly shallow, even in the academic world. The reaction to the facts is often more emotional than rational. Discussions range from realising the dream of purely regenerative electricity based on wind and solar power to a massive increase in the use of solar panels or even the use of other energy generation systems that are largely unexplored, particularly in terms of the scale required. It is widely ignored, although obvious, that the intermittency of renewables requires enormous intermediate storage of energy, on a scale beyond most people’s imagination. A stable and reliable electricity supply is needed to compensate for the fluctuations of renewable energy sources, which can account for up to half of the daily electricity production (1.2 TWh q) and are largely independent of the number of installed electricity generating units. As an illustration, this amount of electrical energy exceeds Germany’s best storage system, pumped hydro, by a factor of twenty, and Germany’s current battery storage by a factor of fifty. There is no viable hydrogen storage system. Any argument for a rapid increase in storage capacity, which is an absolute must, given the urgent need to reduce fossil fuel backup, must face simple boundary conditions. For geological reasons, Germany has little to offer for a massive expansion of pumped-storage power plants, let alone the capacity to abide by the timeframe for implementation. There is a dramatic shortage of lithium, a key raw material required for battery production on the world market. Europe (and Germany in particular) have very little influence on the supply chain. The battery production capacity required to meet Germany’s needs alone exceeds worldwide existing facilities by a factor of 20. Alternative battery technologies are maturing, but the timescales for realising a massive and safe storage system are easily in the order of 20–30 years. There is no hydrogen infrastructure in Germany, and there are no realistic indications that the required production lines, safe transport and storage systems, and electricity needed to power a hydrogen economy will be established in the near future—neither by Germany nor by its European partners. The path to a society with significantly reduced greenhouse gas production therefore requires the exploration of all possible technologies, without ideological bias, and this needs to be addressed immediately. The world, and Germany in particular, has missed the last 30 years to address this problem. Renewables need storage, storage needs energy and infrastructure. A stable base-load power supply can reduce the need for storage and also feed a storage system. In Germany, the baseload power currently consists of fossil-fuel fired power plants and massive imports of electricity. The expected need to increase electric power generation by 2050 is dramatic and will be driven by the feeding of storage systems and an overall increased hunger for electricity despite the drive for energy efficiency. This report focuses on the worldwide development of novel nuclear technologies based on either nuclear fission or fusion. Nuclear fission has proven to be a reliable and greenhouse gas-free technology for a large proportion of electricity production (30 % in Germany in the year 2000 and 62.6 % in France today; see IAEA report w). However, over the past 30 years, most countries with a well-functioning and experienced nuclear industry have lost the know-how to build the many large plants required within a time frame of 10–20 years. Nonetheless, research and development in novel nuclear technologies has brought fusion and fast fission reactors closer to realisation, opening new and more versatile applications of nuclear physics for energy production. This report provides an overview of the different technologies, explaining how they work, the technological challenges that remain and the timescales involved. In addition, it outlines the requirements for energy storage and the role of nuclear technologies, their economic and sociological implications. It also reviews the role of nuclear technologies in the past and addresses the risks and challenges of nuclear waste management (transmutation) and disposal. But the timescales are dramatic everywhere. Despite much progress, new nuclear technologies will not contribute significantly to solving energy storage and electricity generation within the next 25 years. Nonetheless a solution using only non-nuclear technologies within the same timescales seems completely unrealistic. The exceptional energy density of nuclear power remains a major asset for a future with significantly reduced greenhouse gas emissions, both in Germany and globally. It will be essential for the second half of this century and beyond, also in the presence of a suitable energy storage system.