π Energy
The latest technological advances in nuclear energy

Small reactors: a flurry of activity in the world of SMRs

Isabelle Dumé, Science journalist
On March 31st, 2022 |
3 min reading time
Renaud_Crassous_29 (1)
Renaud Crassous
Director of SMR project at EDF
Key takeaways
  • According to the International Atomic Energy Agency (IAEA), there are currently 443 nuclear power plants in operation worldwide. Fifty more are also under construction in 19 countries.
  • In France, CEA, EDF, Naval Group and TechnicAtome are working together on the Nuward SMR, a pressurised water reactor technology designed to meet the growing needs of the global carbon-free electricity market.
  • Originally, SMRs were intended to bring electricity to remote geographical areas - an inevitably limited market. More recently, EDF has put forward the idea of replacing coal-fired power plants with small reactors.
  • The Nuward consortium is currently working on the design phase of its project. This phase, which will be completed by the end of 2022, includes the development of complete architectural plans for the plant and the making of important choices to define the safety of the reactor.

Can small mod­u­lar nuclear reac­tors (SMRs) help us meet our green­house gas emis­sion reduc­tion tar­gets? For many coun­tries, nuclear pow­er in gen­er­al and SMRs in par­tic­u­lar are a solu­tion because they are poten­tial­ly safer and, in prin­ci­ple, faster and cheap­er to build than con­ven­tion­al nuclear reactors.

SMRs, cheaper and more flexible

Accord­ing to the Inter­na­tion­al Atom­ic Ener­gy Agency (IAEA)1, there are cur­rent­ly 443 nuclear pow­er plants in oper­a­tion world­wide. Fifty more are also under con­struc­tion in 19 coun­tries. Most of these are ‘big’ con­ven­tion­al plants that pro­duce more than one gigawatt of elec­tric­i­ty (GWe). They take decades to build, how­ev­er, and cost bil­lions of dollars.

Since fis­sion is a scal­able tech­nol­o­gy, it can be applied to the con­struc­tion of small­er reac­tors, defined as hav­ing a typ­i­cal pow­er of 300 MWe. Much more com­pact and cheap­er, these SMRs can be built in a fac­to­ry and then trans­port­ed in mod­ules to instal­la­tion sites. Ultra-com­pact ‘micro-reac­tors’ are even being designed. These will have an out­put of only 1 to 20 MWe and will be even eas­i­er to trans­port. These reac­tors could be used, for exam­ple, to gen­er­ate heat for indus­tri­al appli­ca­tions such as steel mak­ing, to sup­ply elec­tric­i­ty to com­mu­ni­ties in remote areas and to back up the main elec­tric­i­ty grid.

SMR projects around the world

Accord­ing to the Inter­na­tion­al Atom­ic Ener­gy Agency (IAEA), there are cur­rent­ly about 70 SMR projects world­wide and a wide vari­ety of designs and advanced tech­nolo­gies are being stud­ied. These include very small reac­tors, pres­surised water reac­tors, boil­ing water reac­tors, sodi­um reac­tors, molten salt reac­tors and gas reac­tors. The prod­ucts devel­oped from Gen­er­a­tion III and III+ reac­tors will be ready by 2030 since these are the most advanced tech­nolo­gies today.

SMRs in France

In France, the CEA, EDF, Naval Group and Tech­ni­cAtome are work­ing togeth­er on the Nuward SMR, a pres­surised water reac­tor (PWR) tech­nol­o­gy designed to meet the grow­ing needs of the glob­al mar­ket for com­pet­i­tive decar­bonised elec­tric­i­ty in the 300–400 MWe range. The project is in the pre­lim­i­nary design phase and will be extend­ed to Euro­pean play­ers in sub­se­quent phases.

The idea of work­ing on small pow­er plants is not new in itself. Tech­ni­cAtome, respon­si­ble for the design of Nuward, has been devel­op­ing com­pact reac­tors for near­ly fifty years, par­tic­u­lar­ly for naval propul­sion (sub­marines, air­craft carriers).

SMRs were orig­i­nal­ly intend­ed to bring elec­tric­i­ty to iso­lat­ed geo­graph­i­cal areas – a mar­ket that is inevitably lim­it­ed. More recent­ly, EDF put for­ward the idea of replac­ing coal-fired pow­er sta­tions (there are over 3,000 units to be replaced) with small reac­tors. This is because coal-fired pow­er sta­tions will be phased out over the next few decades to meet car­bon emis­sion reduc­tion tar­gets. This is a much larg­er mar­ket and a series of reac­tors of reac­tors could be built, an inter­est­ing per­spec­tive because it would allow to reduce the cost of a pow­er plant – a sig­nif­i­cant com­pet­i­tive advantage.

In addi­tion, in some parts of the world, the elec­tric­i­ty grid sim­ply does not allow for the instal­la­tion of large pow­er plants because it is too cost­ly and takes time to mod­i­fy the local grid. The pos­si­bil­i­ty of installing an SMR, instead of, say, a coal-fired pow­er plant, which can then be con­nect­ed to the exist­ing grid, is, in prin­ci­ple, eas­i­er. This is there­fore the pri­ma­ry tar­get mar­ket for SMRs.

“There is an effer­ves­cence in the field of R&D and indus­tri­al devel­op­ment of SMRs, the likes of which have not been seen for decades in the nuclear world,” says Renaud Cras­sous, SMR project direc­tor at EDF. “What is also strik­ing here is that it is not only the his­tor­i­cal nuclear com­pa­nies that are active­ly involved, but also a num­ber of start-ups that want to get into nuclear. With this, we might poten­tial­ly iden­ti­fy new cus­tomers and dis­cov­er new uses for nuclear ener­gy in general.”

The development of SMR technology in France

France’s indus­tri­al expe­ri­ence in nuclear pow­er will undoubt­ed­ly be an advan­tage in cer­tain phas­es of SMR devel­op­ment. The gov­ern­men­t’s Plan France 2030 2 will also have an impact on Nuward’s devel­op­ment strat­e­gy since sub­si­dies will be on the order of one bil­lion euros for SMRs in general. 

The Nuward con­sor­tium is cur­rent­ly work­ing on the design of its project. This phase, which will be com­plet­ed by end-2022, involves draw­ing up archi­tec­tur­al plans for the plant and mak­ing impor­tant choic­es as regards the safe­ty of the reac­tor. These deci­sions will then be sub­mit­ted to the rel­e­vant safe­ty author­i­ties. This phase will be fol­lowed by the basic design phase dur­ing which all plant com­po­nents will be detailed, spec­i­fied and then ordered from man­u­fac­tur­ers. A first reac­tor is expect­ed to be oper­a­tional in 2030.

Installing the first series of Nuward reac­tors on French soil would have many advan­tages, not least because it rep­re­sents a unique oppor­tu­ni­ty for a whole net­work of small busi­ness­es in terms of activ­i­ty and jobs. The con­sor­tium has not yet iden­ti­fied a phys­i­cal site and says it will study pos­si­ble sites this year before estab­lish­ing a shortlist.


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