Nuclear energy has now surpassed the seventy years of life, but for some time is in a period of crisis, especially in countries that have long driven the development. Today in Europe there are only two new reactors under construction, Olkiluoto-3 and Flammanville-3. Both EPR ( European Pressurized Reactor ), a new third-generation implant design, however, has shown that delays in construction due to technical problems: the costs have rocketed upwards and date of ‘ entry into operation was delayed for years.
at the same time, the world of energy seemed to go in a very different direction than the classic characteristics of nuclear facilities. Renewables have emerged as the future energy: the real answer to the problem of how to reduce reliance on fossil fuels for electricity production. The Fukushima accident, then, was another blow. Several countries have reconsidered their nuclear strategies and Italy itself, which in 2011 was on the verge of returning to the atom, made a reverse that the same experts now see it as definitive.
a new hope?
But the research and industrial interest around the nuclear power is not turned off. A new type of reactor is receiving much attention in old Europe and some has already been hailed as the possible “key to a low-carbon future.”
This is the Small Modular reactors (SMR), reactors that combine small size compared to the old systems – and a smaller electric power – in modular construction mode. It is precisely this second aspect is the most innovative, confirms Marco Ricotti, professor of nuclear facilities at the Polytechnic of Milan.
“The real news, the leap – says Ricotti – you do it with the modularity: by having a smaller reactor can think of new technological solutions. The components are smaller and can achieve much of the reactor in the workshop. The pieces then are brought to the construction site and, like a Lego, are put together. This would increase the quality, because it is built in a more controlled environment, and also makes it possible to build reactors in series. “
Dimensions and reduced power – the World Nuclear Association defines SMR as reactors with a lower electrical power of 300 MW, one-fifth of that provided in Flammanville – they also give advantages in terms of space for installations, the impact on the territory and on the security front. “The cooling that I have to ensure it is simpler and requires, for example, less water,” says Ricotti.
Many of the new SMR projects make extensive use of so-called passive safety, which uses physical laws to eliminate ‘human intervention and often also the need for pumps and electric energy to ensure the safety of the reactor. This way you avoid the repetition of a scenario like Fukushima, where the exceptional tsunami wave caused the disaster by disabling the electrical generators.
Even nuclear power, in short, is moving to abandon of the past and move towards smaller structures large and bulky structures. “There’s a lot of interest, currently, for this technology,” says Ricotti. “The most active are, in order, the Russians – who are building two reactors mounted on barges for 2017-2018 will be operational. The second are the Chinese, who are building gas reactors with the so-called pebble bed . The third are the Argentines, that in the last twenty years have been pursuing their own project. “
The UK leader
For their part, the Western countries, who seemed to have lost interest in the construction of new plants, are preparing very seriously. The road was opened by the Member States, with the Department of Energy has decided to invest 250 million dollars in this technology. One of the most interesting American projects, the NuScale, works without pumps and electricity and should be approved by the supervisory authorities in the next five years.
In Europe, those who have made the most concrete steps to become the first user of the SMR was the United Kingdom. British Economy Minister George Osborne said he wanted to make the country “a global leader in innovative nuclear technologies” and in the last budget has allocated 250 million pounds in research and development of SMR, also launching a competition for the best design.
Professor Ricotti believes that the next five years will be decisive. “The first truly innovative SMR will be ready and operational. And you will see how will the launch and consolidation of dedicated processes. ” Even our country, he adds, has its role in the development of this new technology: “Italy has entered this field of research since 2000. It has had a certain technological leadership and is even developing a simulator, a system which should simulate the behavior of SMR in factories SIET of Piacenza, who have unique structures in the world. Even some American projects, and the same NuScale, came to Italy to test some components. “
The Italian research, through the Inter-University Consortium for Nuclear Technology Research (CIRTEN) collaborates in international projects with French and English. The crucial question is whether the new power made possible by the SMR can lead to a breakthrough in the nuclear world. “I think so – responds Ricotti – because in recent years you’re going to a rethinking of the structure of electricity production, more distributed leadership. The SMR change the classic nuclear paradigm and would avoid scenarios Fukushima type ‘.
The new SMR reactors are meant to be smaller and more compact. Instead of so-called structures “loop”, in which out of the reactor are the kilometers of piping, the steam generator, pumps and all other installations, the SMR of innovation allows you to enter all external components inside the reactor . A single pressure vessel in which there is fuel, steam generator, pumps. “Much easier to see and understand, with extreme compactness and possibility of eliminating accidents,” says Ricotti.
New and old problems
Of course, the uncertainties surrounding this type of projects are numerous. The first concerns the costs, the true cross of old and new business to the area, as documented mercilessly for years the World Nuclear Status Report , an independent report on the state of nuclear power in the world. In the case of SMR, the least power plant increases the cost per kilowatt-hour, at least on paper, but the hope is that the wider use of passive safety systems can help to keep them low and competitive.
then there are the old problems of nuclear energy, the new design does not eliminate. First, the issue of nuclear waste, which remains one of the most sensitive and thorny for the countries that have or have had a nuclear industry (and Italy, soon, will come back to talk about it seriously). And even the SMR will have to deal with public opposition to nuclear power, especially after the Fukushima disaster.
Things are not made easier by the fact that, by their very nature smaller, modular reactors can be built in many more sites than large and bulky conventional power plants. Only time, in short, will tell if the SMRs are really hoping to give new life to an energy that may seem permanently consigned to the past century.
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