Home / Columns / Helium-3 from the lunar surface for nuclear fusion?
2,15
π Energy

Helium‑3 from the lunar surface for nuclear fusion?

Florian Vidal
Florian Vidal
researcher at the French Institute of International Relations

Since 1969, the return of a human mis­sion to the Moon has nev­er seemed so close. Although sci­en­tif­ic inter­est con­tin­ued to flour­ish, space pro­grammes had for many decades aban­doned it in favour of the Inter­na­tion­al Space Sta­tion and mis­sions to explore the solar sys­tem. Dom­i­nat­ed by the grow­ing com­pe­ti­tion between the Unit­ed States and Chi­na, the return to the Moon is now moti­vat­ed by a desire to study and pos­si­bly exploit resources that can be found there.

Of these, helium‑3 rep­re­sents the most sig­nif­i­cant poten­tial in the field of ener­gy. This non-radioac­tive iso­tope is an ide­al fuel for the oper­a­tion of a fusion reac­tor; it con­sists of fus­ing helium‑3 with deu­teri­um, with the advan­tage of not pro­duc­ing neu­trons. Whilst it is still in its exper­i­men­tal stages, the abil­i­ty to con­tain such ener­gy in the reactor’s con­tain­ment cham­ber could make it a viable ener­gy source.

In Sep­tem­ber 2021 US com­pa­ny, Com­mon­wealth Fusion Sys­tems based in Mass­a­chu­setts, announced the cre­ation of a 20 Tes­la mag­net­ic field using a high-tem­per­a­ture super­con­duct­ing elec­tro­mag­net, which con­sti­tutes a remark­able advance. From this per­spec­tive, the extrac­tion of helium‑3 on the Moon could facil­i­tate the devel­op­ment of this break­through technology.

What is the potential of lunar helium‑3?

As ear­ly as 1988, a NASA report on helium‑3 men­tioned the poten­tial of this iso­tope for use in a nuclear fusion reac­tor1. The­o­ret­i­cal­ly, it offers sev­er­al advan­tages com­pared to cur­rent nuclear pow­er as an abun­dant, low-car­bon ener­gy and no nuclear waste tech­nique. On paper, its advan­tages make it a com­pet­i­tive resource, while this iso­tope is use­ful for oth­er appli­ca­tions includ­ing cryo­gen­ics, quan­tum com­put­ers and MRI lung imag­ing. Also, the Moon is its main reservoir.

For bil­lions of years, the action of solar wind has released high-ener­gy par­ti­cles, includ­ing helium‑3, which has accu­mu­lat­ed on the Moon in the absence of an atmos­phere. A renew­able resource by def­i­n­i­tion, the iso­tope is reg­u­lar­ly deposit­ed on the Moon’s sur­face under the con­stant activ­i­ty of the Sun. How­ev­er, as Ian Craw­ford shows, the notion of the abun­dance of this resource must be weighed up: the high­est con­cen­tra­tion observed in mea­sure­ments car­ried out on sam­ples is 10 parts per bil­lion (ppb), depend­ing on the mass, for an aver­age con­cen­tra­tion of 4 ppb in the regolith lay­er2.

The planned return to the Moon

As a pre­req­ui­site for the instal­la­tion of a human base, many states (India, Rus­sia, Chi­na, Unit­ed Arab Emi­rates, etc.) are prepar­ing new lunar mis­sions in the com­ing years. By far, the Artemis pro­gramme, sup­port­ed by NASA, is the most suc­cess­ful at this stage for this planned return. Along­side the Unit­ed States, many coun­tries such as Aus­tralia, Brazil, Italy, Japan, and Lux­em­bourg have joined this ambi­tious project. Chi­na, togeth­er with Rus­sia, is also con­sid­er­ing the estab­lish­ment of a lunar base. How­ev­er, the spec­i­fi­ca­tions for such an under­tak­ing remain incom­plete for the time being, both in terms of the finan­cial resources and the tech­ni­cal arrange­ments to reach the tar­get set for 2030.

Clear­ly, a per­ma­nent instal­la­tion requires the con­struc­tion and main­te­nance of infra­struc­ture through the use of local­ly avail­able resources and the inten­sive use of robots. In this regard, the Aus­tralian com­pa­ny Luyten is look­ing to deploy 3D print­ing tech­nol­o­gy to pro­vide on-site con­struc­tion solu­tions3. In oth­er words, the aim is to imple­ment an arti­fi­cial lunar ecosys­tem to facil­i­tate trav­el to Earth. To achieve this ambi­tion, the French incu­ba­tor TechThe­Moon, based in Toulouse, is the first in the world ded­i­cat­ed to devel­op­ing a per­ma­nent set­tle­ment on the Moon4. Despite this emu­la­tion, the estab­lish­ment of a human colony remains a dis­tant prospect. A recent NASA audit report points to cumu­la­tive delays in the Artemis pro­gramme, par­tic­u­lar­ly in the devel­op­ment and test­ing of the lunar mod­ule, which de fac­to post­pones the mis­sion beyond 20245.

China begins the race for this new mining frontier

Chi­na has demon­strat­ed a mete­oric rise in its space activ­i­ties head­ing towards the moon – both eco­nom­i­cal­ly and tech­no­log­i­cal­ly. As a fun­da­men­tal step in the devel­op­ment of its space pro­gramme, Chi­na sent its first probe into orbit around the Moon in 2007. Since then, the Chang’e 4 (2018) and Chang’e 5 (2020) mis­sions have made sig­nif­i­cant progress in the knowl­edge and study of data on the topog­ra­phy and com­po­si­tion of the soil. One of the objec­tives of these trips is to deter­mine the exact amount of helium‑3 present. To this end, the Bei­jing Research Insti­tute of Ura­ni­um Geol­o­gy (BRIUG) is mea­sur­ing the con­tent of helium‑3 in the lunar soil, eval­u­at­ing its extrac­tion para­me­ters, and study­ing the ground fix­a­tion of this iso­tope. These advances also reflect Bei­jing’s over­all strat­e­gy to con­trol ter­res­tri­al min­er­als and met­als and their use.

Over­all, oth­er coun­tries are fund­ing pro­grammes to analyse the lunar soil, such as the future mis­sion of the first Emi­rati rover sched­uled for 20226. With the help of the Japan­ese com­pa­ny Ispace’s lunar lan­der, the “Rashid” rover will study its geo­log­i­cal com­po­si­tion and prop­er­ties. These mis­sions will undoubt­ed­ly help to assess its min­ing potential.

Many obstacles

Sci­en­tif­ic mis­sions are bound to con­tin­ue over the next decade to con­tin­ue sur­vey­ing regolith­ic rocks in new lunar ter­ri­to­ries. This is an invalu­able piece of sci­en­tif­ic infor­ma­tion that reflects one of the foun­da­tions of the human space explo­ration; based on the pos­si­bil­i­ty of exploit­ing extrater­res­tri­al resources that appear to be unlim­it­ed. In any case, the devel­op­ment of an extra-ter­res­tri­al min­ing indus­try entails invest­ment and infra­struc­ture con­straints such that the deploy­ment of exist­ing renew­able resources on Earth would remain less cost­ly. In fact, the ener­gy cost of lunar helium‑3 – from extrac­tion to use in a nuclear fusion reac­tor – would make it at most a rather mar­gin­al con­tri­bu­tion to our long-term ener­gy needs.

While exist­ing tech­no­log­i­cal and finan­cial bar­ri­ers osten­si­bly hin­der the launch of such a ven­ture out­side the Earth sys­tem7, sus­tained research and devel­op­ment poli­cies in sev­er­al coun­tries are in this sense a way of keep­ing the pos­si­bil­i­ty open. All in all, this fea­si­bil­i­ty could be unrav­elled when a tech­no­log­i­cal thresh­old is crossed that cor­re­lates with its eco­nom­ic prof­itabil­i­ty. Final­ly, cur­rent inter­na­tion­al treaties do not pro­vide a polit­i­cal and legal frame­work for min­ing activ­i­ties on the Moon. In the mean­time, thought must be giv­en to the sta­tus of the celes­tial object, which could ulti­mate­ly be like that of Antarc­ti­ca, by becom­ing a neu­tral space ded­i­cat­ed to science.

1https://​ntrs​.nasa​.gov/​c​i​t​a​t​i​o​n​s​/​1​9​8​9​0​0​05471
2http://www.homepages.ucl.ac.uk/~ucfbiac/Lunar_resources_review_preprint_accepted_manuscript.pdf
3https://​www​.luyten3d​.com/​p​r​o​j​e​c​t​-​m​e​e​k​a​-​p​r​e​s​s​-​r​e​lease
4https://​techthe​moon​.com/
5https://oig.nasa.gov/docs/IG-22–003.pdf
6https://​www​.nation​al​geo​graph​ic​.com/​s​c​i​e​n​c​e​/​a​r​t​i​c​l​e​/​p​a​i​d​-​c​o​n​t​e​n​t​-​u​a​e​s​-​g​i​a​n​t​-​l​e​a​p​-​i​n​t​o​-​space; // https://www.nature.com/articles/d41586-020–03054‑1
7https://​the​con​ver​sa​tion​.com/​d​e​s​t​i​n​a​t​i​o​n​-​m​o​o​n​-​i​s​-​i​t​-​t​i​m​e​-​f​o​r​-​u​s​-​t​o​-​s​e​n​d​-​a​s​t​r​o​n​a​u​t​s​-​b​a​c​k​-​1​59486

Contributors

Florian Vidal

Florian Vidal

researcher at the French Institute of International Relations

work focuses on resources and governance in the Anthropocene, in particular mining issues in remote areas. He is also an associate researcher at the Interdisciplinary Laboratory of Future Energies (University of Paris).