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.