L'Energy Amplifier di Rubbia : gli studi per la produzione di un'energia nucleare pulita ed il loro impatto sul piano economico

The growing interest towards new energy forms is a common feature of many different studying fields: physics, engineering, economics and politics. The main reason is that human population is growing fast (there's a prevision of about nine billion people in 2050) and with it is increasing the energy request, both for the industrialized world and for the developing countries. This means that the actual organization of the energy market will not be able to satisfy the needs of the near future: clean energy for everybody. The International Energy Agency provided a "business as usual" scenario where is shown that by the year 2030 the world energy demand will be 70% higher than now and the electricity demand would follow the same pattern, needing somewhat like 3475 GW of new electric power. The logic conclusion is that we'll need all the energy forms we know: fossil fuels, nuclear and renewable energy. Nowadays the energy - and particularly the electricity - market is facing large problems: global warming and dependence from OPEC countries (64.4% of world oil production comes from only 10 countries) for the fossil fuels; radioactive wastes and public non-acceptance for the nuclear energy; non-competitiveness for the renewables. The actual world electricity supply system can be so summarized: coal 38.4%; hydro 18.4%; nuclear 17.7%; gas 14.8%; oil 9.3%; others 1.4%. But things are going to change quite fast in the future, both for international policies and for intrinsic limits. Coal will remain one of the most important fuels, but his opportunity cost will grow because of the need of lowering his CO2 emissions in respect of the Kyoto Agreements. Gas is going to improve its importance in the electricity generating market, thanks to its cleaner burning, but it is limited by the fact of being a meagre (scarce) resource. Hydropower has many exploitation possibilities in the developing countries, but not in the industrialized world where almost all the resources are already being used. Renewable energies are still too expensive to produce massive electricity and, in spite of public general acceptance, have shown to produce nearly as much polluting wastes if their complete cycle is considered. Nuclear energy, finally, finds its biggest limits in its relationship with public. In fact from the electricity generating cost point of view it is the cheapest form actually available. However problems with public come from: criticality accidents, radioactive wastes, plutonium traffic and poor knowledge and comprehension of the nuclear fuel cycle and engineering. From such analysis comes out the importance of Nobel Prize Rubbia's project of a new, clean and safe nuclear plant. The Energy Amplifier is an accelerator driven system which furnishes from the outside the energy that is necessary to start the nuclear reaction. The accelerator sends a proton beam into the reactor, here there is a spallation target (made up of lead) that creates neutrons. These neutrons, hitting the fuel's atoms (thorium), start the reaction in a completely safe way as into the Energy Amplifier the criticality factor is less the one, which means that to make the reaction happen there's the continuos need for an external neutrons source. Moreover Rubbia's Amplifier can also burn radioactive wastes (precisely transuranic wastes) and lower the general radioactivity of the remaining wastes (fission products' radiotoxicity is reduced of 200000 times by the end of the cycle). Uranium and plutonium traffic would be easily lowered by the fact that the Energy Amplifier reload operation happens one in five years. Finally, this reactor would be able to use the military plutonium coming from disarmament. The electricity generating cost, calculated over CERN's actual design (but the project is still under study so things could change a little), shows out to be the cheapest (20.08 USmill/kWh) and particularly it is one half of the same cost for gas and about two thirds of actual nuclear power. It must be said that not everybody agrees with CERN's estimate, but even if the Energy Amplifier cost should be the same of a normal nuclear reactor (about 2450 US$/kWe installed) there would be such a gain in security and cleanness that it's opportunity cost would be the best. Now the real problem is to find the funds (about 1.3 billion US dollars) to make such a project become reality or, at least, reach the stage of a full-scale experiment The point is: who and why should take the risks of financing it? The answer is not as clear as it seems: the cost is too high for a single State, the European Community has conflicting interests (by 2020 it's energetic autonomy will lower from 50% to 30%, but meanwhile there are different countries' positions towards traditional nuclear power, as shown by the enormous economical importance of nuclear power in France and by complete public opposition in Italy) and the private sector is hold back by the fact of getting any possible economic return not before ten - twenty years.