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

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.

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.

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.”

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.