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.