FUSION ENERGY SOLUTION TO GLOBAL WARMING AND FOSSIL DEPLETION

The world’s population is projected to increase from seven billion people today to nine billion by the end of this century and the current power demand of 12 TW is expected to double during the following decades. About 80% of the current energy needs are being supplied by diminishing fossil fuels (coal, oil, gas) that are becoming more difficult and costly to extract. These energy sources currently emit some 40 GtCO₂e per year of greenhouse gases into the atmosphere, warm the Earth’s climate system, melt glaciers and produce sea level rise, and have the potential to uproot hundreds of millions of people. Harvesting of nuclear energy from the splitting of heavy nuclei (uranium, thorium, plutonium) in nuclear fission reactors can produce substantial amounts of base load power, but this energy source is also unsustainable and some products of reactions produce the publicly unacceptable long-lived (millions of years) radioactive products that we have not yet been able to manage properly nor convince the public that the accidents such as at Chernobyl and Fukushima can be avoided. Harvesting the required energy with solar thermal, wind, photovoltaic and biomass energy conversion systems from the 10⁵ TW of power delivered by the Sun to our planet requires the development of new energy supply technologies, overcoming security issues of energy production and distribution, and satisfying the social constraints posed by various cultures with different resources and aspirations. The conversion of just 0.1 gram of hydrogen to energy every second is equivalent to the power of 10 TW and therefore here lies the great interest in exploiting the fusion energy for humanity. The fusion of deuterium and tritium has been achieved in several experimental reactors where the plasmas are confined with magnetic fields and there is high optimism that this will also be achieved with laser and ion beams. The plasma confinements and reactor technologies of tokamaks and stellarators are paving the way for building demonstration fusion reactors and subsequently commercial fusion power plants during the second half of this century. The reactor technologies that implement the magnetic and inertial plasma confinement concepts are assessed for producing sustained plasma ignition, external plasma heating, control of plasma instabilities, developments of low-activation and high strength materials, coolants for removing fusion energy from the reactor, breeding tritium in the blanket of the reactor for achieving fuel self-sufficiency, and ensuring that fusion power plants operate safely and do not pose burden to future generations.. Sustainability of fusion energy requires the long-term availability of fusion fuels and reactor components materials, social acceptability, minimization of waste products, and safe operation of fusion power plants. These and other issues assessed strongly suggest that the fusion energy is a viable solution to global warming and fossil depletion and that it can greatly contribute to human development.