1. Introduction

The smart cities of tomorrow will need far more than just power for homes and businesses. As cities increasingly rely on electric vehicles, the need for reliable, fast-charging infrastructure will grow. Clean power will be needed to charge fleets of electric buses, trams, taxis, personal cars and autonomous transport systems. They will also require energy for edge computing, real-time monitoring, and the myriads of Internet of Things (IoT) devices that will keep the city running smoothly^[2]. Similarly, data centres, which are critical to the functioning of smart cities, will consume vast amounts of energy. These centres must be online 24/7 to process the data flowing in from traffic cameras, air quality sensors and public safety systems. The rise of artificial intelligence (AI) has recently also contributed to a massive build-out of new data centres. In this respect, it has been argued that data centres will soon become the backbone of the newly emerging smart cities^[3]. Still, power consumption has become one of the key bottlenecks to further expansion^[4]. In this respect, nuclear power has been currently identified as an option that is seriously considered for deployment in the forthcoming decade^[5].

On 7^th March 2023, the Swedish data centre operator Bahnhof announced a plan to launch a nuclear microreactor to power its future data centre. The prospective microreactor is envisaged to be operated in the industrial site of the Hjorthagen area of Stockholm. It will provide electricity for a new data centre, 30.000 households, and heat for homes and offices^[6]. For the time being, Bahnhof operates seven data centres in various cities in Sweden. The company is well known for its underground data centre, Pionen White Mountains, in central Stockholm. It is built in a former government nuclear bunker and has backup power provided by diesel engines recovered from submarines. The fact is, however, that the recently announced plan of the Swedish data centre operator Bahnhof does not represent the only existing endeavour aiming at powering a data centre with a nuclear microreactor. In July 2024, the US-based nuclear start-up Nano Nuclear Energy Inc. announced it had signed a Memorandum of Understanding (MoU) with Blockfusion Ventures, an affiliate of crypto mine firm Blockfusion USA, Inc. Under this MoU, Nano Nuclear will explore the potential integration of its microreactor technologies with Blockfusion’s remote data centre in Niagara Falls, New York^[7]. In October 2024, Google signed an agreement with nuclear startup Kairos Power to build seven microreactors that will supply electricity to its data centres until 2035^[8]. Another MoU was adopted in December 2024 between Nano Nuclear Energy and Digihost Technology to advance the transition to carbon-free energy for Digihost’s high-tech operations, including AI-driven data centres and digital asset colocation programmes^[9].

The prospective deployment of microreactors to power future data centres has already attracted considerable attention from scholars who are dealing with technologies, smart cities, and energy transition^[10]. At the same time, there is a common understanding that a robust legal and regulatory framework must accompany any future deployment of microreactors^[11]. This article argues that the prospective deployment of microreactors also implies a considerable paradigm shift in law. While classical nuclear law had to address the potential risks arising from large nuclear reactors, future nuclear law will need to reflect the specifics arising from the miniaturisation^[12] of nuclear technologies.

Having said this, the need to address challenges arising from technology miniaturisation does not occur exclusively in the nuclear sector. A very similar process is currently ongoing in the field of space technologies. Here, the miniaturisation of satellites has opened the door to missions that a larger satellite could not accomplish, such as providing constellations for low data rate communications, using formations to gather data from multiple points, in-orbit inspection of larger satellites, etc^[13]. The increased commercial interest in small satellites has recently triggered the adoption of national space acts, addressing their licencing, registration and liability issues^[14]. In Europe, such national space acts have been recently adopted in Portugal (2019), the Grand Duchy of Luxembourg (2020) and Slovenia (2022). In 2023, both Cyprus and the Principality of Liechtenstein adopted their space acts. Legislative activities towards adopting national space acts are currently pending in the Federal Republic of Germany, Latvia and Spain. France recently undertook the update of its national legal framework, including its Law of 2008 on space activities. On 28 June 2024, French lawmakers released a decree and two orders on authorisation and technical regulations applicable to space activities^[15]. In Italy, a draft of a national act on Provisions for the Space Economy was submitted to the Parliament on 10 September 2024^[16]. At the same time, the adoption of an EU Space Law is pending at the European Union level^[17].

This article aims to argue that similar legislative developments regarding microreactors may be expected in the forthcoming decade. The Accelerating Deployment of Versatile, Advanced Nuclear for Clean Energy Act of 2024, which President Joe Biden signed on 9 July 2024, represents the first demonstration of these developments, which will continue in the future.

2. A fleet of microreactors is on the horizon!

The announcements on the prospective deployment of microreactors to power data centres must be understood in the context of the recent boom of commercial interest in advanced nuclear technologies. Very recently, the 2024 edition of the OECD/NEA Small Modular Reactor Dashboard presented 56 various projects^[18] of small modular reactors (SMRs) that are currently under development worldwide. Both public and private institutions in different countries^[19] are actively participating in efforts to bring SMR technology to fruition within this decade. As a class of reactors, SMRs are defined by their smaller size^[20]. However, there is considerable variety within this class of reactors; they vary by power output, temperature output, technology and fuel cycle. Several SMRs are based on existing commercially deployed light water technologies. In contrast, others are based on advanced design concepts, offering a range of sizes (from 1 MWe to over 300 MWe) and a range of temperatures (from 285°C to more than 850°C) to meet the specific energy needs of hard-to-abate industrial sectors^[21]. Having said this, one must bear in mind that the primary aim of SMR development is not to replace the nuclear power plants in operation already but to provide an advanced and alternative source of energy in the future^[22]. Existing projects target varied outputs and different applications, such as electricity, hybrid energy systems, heating, hydrogen production, water desalinisation and steam for industrial applications. For the time being, the following benefits of a prospective deployment of SMRs have been identified: Firstly, SMRs are expected to play an essential and increasingly important role in supporting net-zero targets^[23]. Secondly, given their smaller footprint, SMRs can be sited in locations not suitable for larger nuclear power plants. Prefabricated units of SMRs can be manufactured and then shipped and installed on-site, making them more affordable to build. In this respect, SMRs offer savings in cost and construction time, and they can be deployed incrementally to match increasing energy demand^[24]. Also, SMRs can be installed into an existing grid or remotely off-grid as a function of their smaller electrical output, providing low-carbon power for industry and the population. Lastly, proposed SMR designs are generally more straightforward, and the safety concept for SMRs often relies more on passive systems, such as low power and operating pressure. This means that in such cases, no human intervention or external power or force is required to shut down systems^[25].

Microreactors represent a specific type of these newly emerging advanced nuclear technologies^[26]. The International Atomic Energy Agency (IAEA) defines them as very small reactors with power levels anticipated generally ranging from less than 1 MWe to 30 MWe^[27]. The US Department of Energy (DOE) defines^[28] microreactors by using three distinctive features:

Microreactors are factory-fabricated: All components of a microreactor are fully assembled in a factory and shipped to the location.

Microreactors are transportable: Smaller unit designs will make microreactors very transportable by truck, shipping vessel, plane or railcar.

Microreactors are self-adjusting: These advanced nuclear technologies won’t require many specialised operators and would utilise passive safety systems that prevent any potential for overheating or reactor meltdown.

At the end of 2024, thirteen microreactor projects worldwide were under various stages of development worldwide^[29]. Many of these projects reflect the exponential growth of data usage and global internet traffic, which is expected to continue and even accelerate due to the wide adoption of AI. To meet this demand, data centre planners consider not only the affordability aspects but also sustainability, supply security, and social impact. In this respect, microreactors have been recently discussed as a comprehensive, emission-free and renewable-led solution for powering data centres in the future. In this respect, Westinghouse is currently developing its eVinci™ microreactor, which combines microreactor’s innovative design with 60+ years of commercial nuclear design and engineering, creating a cost-competitive and resilient source of power with superior reliability and minimal maintenance. Its small size allows for transportability and rapid, on-site deployment in contrast to plants requiring large amounts of construction^[30]. In September 2024, Westinghouse submitted its eVinci™ Microreactor Preliminary Safety Design Report to the US Department of Energy (DOE). Westinghouse announced that the move advances the eVinci™ microreactor’s testing for future use on the commercial market, including data centres^[31]. Other microreactors for powering data centres are currently being developed by the NuScale Power Corporation (NuScale) and by Nano Nuclear Energy Inc^[32]. Having said this, one must bear in mind that the prospective applications of microreactors are not limited to data centres powering. It has been envisaged that microreactors can power remote urban settlements and mining operations, produce hydrogen, or provide power on a space basis. Also, they are planned to be operated by universities and research institutions for scientific purposes^[33].

For the time being, microreactor deployment is envisaged in the forthcoming decade. For example, the MoU between Google and the nuclear startup Kairos Power foresees that the first microreactor will power Google’s data centre by 2030, and the following six installations will be completed by 2035^[34]. The microreactor, which is subject to the MoU adopted between Nano Nuclear Energy and Digihost Technology, is envisaged to be operated in 2031. Also, Bahnhof foresees the launch of a microreactor to power the future data centre at the Hjorthagen area of Stockholm within the next decade.

Having said this, one may expect that a brand-new type of advanced nuclear technology will be deployed in the forthcoming decade. However, any such deployment must be accompanied by the establishment of a transparent and predictable legal framework.

3. Miniaturisation as a trigger for a paradigm shift in nuclear law

The existing legal framework for the peaceful uses of nuclear energy has been established to address risks potentially arising from large (conventional) nuclear reactors. However, microreactors, which will probably be deployed in the next decade, demonstrate several significant challenges that differentiate them from installations that have been in operation in the US and Europe until now^[35]. The feature of miniaturisation implies the main challenges arising from the prospective deployment of microreactors^[36]. These challenges can be outlined as follows.

3.1. Reduction of size & risks

Microreactors are the most minor type of SMRs^[37]. They are 100 to 1000 times smaller than conventional nuclear reactors and range in capacity from 1 to 30 MWe, compared to 30 to 300 MWe for SMRs. The fact is, however, that microreactors do not represent a mere miniaturisation of large nuclear reactors. One of the significant differences between large reactors and microreactors is that microreactors won’t require many specialised operators and will utilise passive safety systems that prevent any potential for overheating or reactor meltdown and subsequent radioactive release into the environment. Thus, the prospective risks arising from microreactors will be considerably lower in the future than those arising from conventional reactors^[38].

However, nuclear law has been designed to address risks arising from conventional nuclear reactors^[39]. To address these risks, legal mechanisms have been established in the fields of nuclear safety and nuclear liability. While nuclear safety aims to minimise the risk of a radioactive release into the environment, nuclear liability schemes are intended to govern cases involving nuclear damage. In the field of nuclear safety, the Convention on Nuclear Safety provides^[40] that its Contracting Parties must adopt a system of licensing regarding nuclear installations and prohibit the operation of a nuclear installation without a licence^[41]. Further, the Convention confers licencing of nuclear installations to the hands of national regulatory authorities. In the Euratom Community, these requirements have been reiterated in by the Directive 2009/71/Euratom^[42]. With respect to this requirement, rules for licencing procedures have been provided by the national legislation and implemented by national regulatory authorities. However, these licencing procedures have been designed for large reactors rather than for microreactors. Thus, national legal frameworks provide for rather complex and lengthy procedures that match the level of risk implicated by conventional reactors. Facing the prospective deployment of microreactors in the forthcoming decade, countries interested in hosting these technologies must adopt rules of licencing that will fully reflect the potential number of operated installations and the considerably reduced risks arising from the operation of such installations^[43].

The feature of miniaturisation also has significant implications for the regime of nuclear liability. The existing regime of liability for nuclear damages was designed in the 1960s to reflect potential transboundary risks arising from then-existing nuclear technologies. Two international liability regimes – the Paris-Brussels regime and the Viennese regime – provide for liability rules, which need to be further transferred into the national legislation. Having said this, one must bear in mind that the existing regime of nuclear liability has been tailor-made for risks arising from large reactors^[44]. In the existing nuclear liability regime, the operator of the nuclear installation is exclusively liable for any damages that may occur because of an incident in the respective installation. National legislation provides for mandatory insurance for this liability and requires the operator to maintain it in a certain amount during the whole operation of the licenced installation. While these amounts for compulsory insurance have been determined with respect to the risks potentially arising from large reactors, any future deployment of microreactors will require reconsideration of these amounts^[45].

3.2. Decentralisation

Prospective deployment of microreactors will significantly contribute to the decentralisation of power supply, dramatically changing the landscape of power supply. In the past, large reactors have represented a tool for centralising power supply from a few power generation centres in the territory of the state. Microreactors will enrich this landscape of power generation. Large reactors will cease to represent the only source of nuclear power in the state. Nuclear power will be generated from a much higher number of centres, which will be distributed according to the delivery needs of the respective urban communities, industrial regions, etc^[46].

The fact is, however, that the deployment of microreactors can change the current paradigms in nuclear law enforcement in different ways. Apart from the requirement for licencing of nuclear installations, the Convention on Nuclear Safety also provides that national legislative and regulatory framework must establish and maintain «a system of regulatory inspection and assessment of nuclear installations to ascertain compliance with applicable regulations and the terms of licences»^[47]. Under the safety scheme of the Convention, both regulatory inspections and assessments of nuclear installations must be realised by national regulatory authorities. In this respect, the Convention requires that national regulatory authorities be provided with adequate authority, competence, and financial and human resources to fulfil their assigned responsibilities^[48]. The nuclear safety legislation, as adopted under the Euratom Community, has reiterated these requirements by the Directive 2009/71/Euratom^[49]. Taking the prospective deployment of microreactors into consideration, the implementation of these requirements will demonstrate a considerable challenge for national regulatory authorities. They have been designed to oversee a relatively limited number of large reactors operated in the state territory. With the arrival of advanced nuclear technologies, the number of installations that will need surveillance and assessment will increase rapidly. At the same time, the prospective deployment of microreactors will also increase the demands on the qualifications of the official staff of the regulatory authorities. Undeniably, this will also have an impact on the financing of the regulatory regime.

Prospective microreactors’ decentralised character will also impact the management of the nuclear waste they produce^[50]. With this respect, the Joint Convention on the Safety of Spent Fuel Management and on the Safety of Radioactive Waste Management stipulates that nuclear waste «should, as far as is compatible with the safety of the management of such material, be disposed of in the State in which it was generated»^[51]. In the Euratom Community, the obligation of the state to provide a repository to dispose of nuclear waste produced within its territory has been reconfirmed by Directive 2011/70/Euratom^[52]. The prospectively increasing number of microreactors may, however, trigger the interest of concerned states in another solution, which has been presumed both under the Joint Convention^[53] and under the Euratom Community^[54]. Those countries where a microreactor will represent the only source of nuclear waste may be interested in international (shared) repositories to avoid the necessity to establish their own repository. However, international repositories may also represent an option for the disposal of nuclear waste in transboundary agglomerations and industrial parks, where microreactors will be deployed^[55].

3.3. Location

The prospective location of future microreactors represents another significant difference in comparison to the large reactors^[56]. The location of large reactors has been due to safety concerns that have traditionally been planned at a considerable distance from large urban settlements. The distance between urban settlements and nuclear installations is being covered by emergency planning zones (EPZ), which have been designed to protect the population from the potentially disastrous impacts of a nuclear incident^[57].

In strict contrast, the current endeavours with microreactors envisage placing them in the centres of the cities. For example, the Swedish data centre operator Bahnhof plans to operate a microreactor in the northeastern part of central Stockholm, an area populated by approximately 9,500 inhabitants^[58]. The fact that the microreactor will be constructed underground will protect it from seismic activity, other natural hazards and also from potential terroristic attacks^[59]. Thus, one significant precondition for any deployment of the microreactors in these locations is establishing special emergency planning zones, which will be tailor-made to the risks potentially arising from these advanced nuclear technologies. The task of the national regulatory authority, together with the IAEA, will be this.

3.4. Production

The number of producers of large reactors is somewhat limited. In stark contrast, the number of potential suppliers of microreactors is constantly increasing^[60]. Thus, in the future, a potential buyer of these advanced nuclear technologies will have much more choices among suppliers of technologies than the current buyers of large reactors. A smooth transfer of these technologies will be very much more manageable when a shared understanding of safety standards is found between the national regulatory authority of the supplier and the regulatory authority of the buyer^[61]. Such mutual recognition of certifications would dramatically contribute to a smooth transfer of technologies. The platform for such mutual recognition can be provided either by bilateral agreements between the concerned national regulatory authorities or by multilateral action (see below).

One must remember that miniaturisation hasn’t been exclusive to nuclear technologies. A very similar process is pending in the space technologies sector, where small satellites, including nanosatellites (also referred to as CubeSats or NanoSats)^[62], are being developed and deployed on a large scale. To establish a transparent and predictable legal framework for launching these installations, brand-new space acts have been adopted in the last few years on the national level in Europe (for example, in Portugal – in 2019, Luxembourg – in 2020, and Cyprus – in 2023) and beyond (in the United Arab Emirates – in 2023, in Brazil – in 2024). Consequently, one may observe a very rapid legislative reaction to the newly emerging technology worldwide. In the European Union, a legislative initiative is currently pending to design and adopt an EU Space Law that will provide for an EU-wide basic standard in the sphere of safety.

The field of space legislation is inspirative in two ways: firstly, one may expect that as soon as a critical number of microreactors arrive on the market, national legislators will also commence establishing their own rules to address risks arising from these technologies. Secondly, the already-adopted national space acts may provide inspirational solutions on how to tackle the issue of miniaturisation. For example, the Portuguese Space Decree-Law of 2019^[63] provides that space activities shall be subject to a compulsory license, which is to be issued by the competent national authority. In this respect, the Space Decree-Law has introduced two specific types of licences, which will authorise launch and/or return operations, as well as command-and-control operations. A unitary license (licença unitária) may be granted, which applies to each type of space operation and is awarded to the respective operator^[64]. Also, space activities may be authorised by a global license (licença global) that applies to several space operations of the same type and is granted to the respective operator^[65]. Having said this, one must bear in mind that any feature similar to a global licence is very alien to the classical system of nuclear law. This is because large reactors require profound and distinctive licensing concerning their unique characteristics. However, with respect to microreactors, which will imply much lower risk and will be much more numerous, licencing several installations in one act could represent a viable solution in the future^[66].

4. Towards a modern nuclear law

On 9 July 2024, US President Joe Biden signed the Accelerating Deployment of Versatile, Advanced Nuclear for Clean Energy Act of 2024 (the ADVANCE Act of 2024). The main aim of the newly adopted legislation is to «provide incentives for developing and deploying new nuclear technologies, such as reduced licensing fees and prize awards for deploying such technologies»^[67]. The ADVANCE Act of 2024 provides for a tailor-made framework for small modular reactors (advanced nuclear reactors in the wording of the Act). While it does not mention microreactors explicitly, they will fall under the scope of application of this newly adopted legislation^[68]. The reaction of the ADVANCE Act of 2024 to the emergence of advanced nuclear technologies is twofold: On one hand, a comprehensive set of provisions is focused on American Nuclear Leadership. Pursuant to these provisions, the Nuclear Regulatory Commission (the NRC) must coordinate certain international activities with respect to the advanced nuclear technologies within respective international organisations^[69]. Also, the NRC has been empowered to establish the “International Nuclear Reactor Export and Innovation Branch”, to carry out such international nuclear reactor export and innovation activities as the NRC determines to be appropriate and within its mission^[70]. Thus, a good portion of the provisions of the newly adopted ADVANCE Act of 2024 focuses on the USA’s international activities in the field of advanced nuclear technologies.

Secondly, the ADVANCE Act of 2024 also introduced several provisions entitled Developing and Deploying New Nuclear Technologies. In contrast to the provisions mentioned above, these provisions focus on supporting the deployment of advanced nuclear technologies in the USA by reducing specific fees and introducing prize awards. A special regime is being established to help those advanced nuclear technologies that will serve non-electric applications, such as hydrogen production, medical isotope production, water desalinisation, etc^[71]. Also, the newly established legislation has introduced a special regime for the deployment of advanced nuclear technologies to the brownfields^[72].

The ADVANCE Act of 2024 is the first legislative act worldwide to address the phenomenon of miniaturisation in nuclear technologies. At the same time, its provisions reflect the fact that advanced nuclear technologies, including microreactors, are currently in their infancy. Thus, instead of providing detailed rules on their licencing and operation, the ADVANCE Act of 2024 merely provides support for further development on a domestic and international level.

Despite the potential benefits the microreactors may bring, no similar legislation has been passed in Europe so far. One may expect that the gradual deployment of advanced nuclear technologies will also trigger legislators in Europe to provide transparent and competitive national rules in this field. Such legislative amendment has been recently adopted in Sweden^[73]. However, the microreactors also represent a salient challenge for the Euratom Community itself^[74]. While any rules in domestic legislation are missing, the Euratom Community represents a platform for setting basic safety and liability rules for these new types of nuclear technologies. At the same time, the Euratom Community is also capable of establishing a framework for mutual recognition of certifications and, consequently, enabling easy circulation of technologies. In the same fashion as the field of space technologies, establishing common European rules will strengthen European autonomy also in the field of advanced nuclear technologies. At the same time, it will make Europe more competitive, transparent, and attractive to innovators.

Having said this, the authors of this article believe that future modern nuclear law must be capable of addressing all peculiarities arising from the miniaturisation of advanced nuclear technologies. Very similar to the field of space law, the law governing advanced nuclear technologies must also follow those basic principles, as recently recognised by the international community of States^[75]. Any future legal framework must first respect the principle of nuclear safety^[76]. Also, the permission principle^[77] and the continuous control principle^[78] must be applicable to advanced nuclear technologies. The same applies to the compensation principles, which call for adequate compensation in the event of a nuclear accident. However, all these principles must be considered in future legislation in the way peculiarities of technological miniaturisation will be reflected.

5. Conclusions

Data usage and global internet traffic have experienced exponential growth since the mid-2000s, and the trend is expected to continue and even accelerate due to the wide adoption of artificial intelligence. The total global energy demand for data centres now exceeds the consumption of most economies, and they emit around 2% to 4% of global greenhouse gas emissions. To meet this demand, data centre planners must consider not only the affordability aspects but also sustainability, supply security, and social impact. In this respect, nuclear microreactors have been recently discussed as a comprehensive, emission-free and renewable-led solution for powering the data centres. Several MoUs have been signed during the last few years, and they envisage the deployment of microreactors as a source of power for data centres in the forthcoming decade. Microreactors demonstrate several significant challenges that differentiate them from large (conventional) reactors that have been in operation until now. Their miniature character implies a considerable decrease in risks arising. Also, they may serve as a tool for the decentralisation of power supply and can be located right in the very centre of urban settlements. Lastly, microreactors will be very easily transportable by land, sea, or air.

This article argued that the future deployment of microreactors does imply a considerable paradigm shift towards a modern nuclear law. This is very similar to the space sector, where space law has been needed to address the gradual deployment of small satellites; also, nuclear law is currently being triggered to establish new rules, reflecting this paradigm shift arising from miniaturisation. The ADVANCE Act of 2024, adopted very recently in the USA, represents only the very first legislative reaction worldwide to the phenomenon of miniaturisation in nuclear technologies. This article envisages that many others will come and urges the Euratom Community to take an active role in this process.

1. This paper was written under the umbrella of the project “A fleet of small modular reactors on the horizon! Do we need a new nuclear law?” (registration number 24-10062S), supported by the Czech Science Foundation. ↑
2. See D. Rehman, P. Faria, L. Gomez, Z. Vale, Future of energy management systems in smart cities: A systematic literature review, in Sustainable Cities and Society, 96, 2023, article 104720. ↑
3. See P. T. I. Lam, D. Lai, Ch. Leung, W. Yang, Data centers as the backbone of smart cities: principal considerations for the study of facility costs and benefits, in Facilities, 39, 2021, pp. 80-95. ↑
4. See N. Ortar, A. R. E. Taylor, J. Velkova, P. Brodie, Powering ‘smart’ futures: data centres and the energy politics of digitalisation, in S. Abram, K. Waltorp, N. Ortar, S. Pink (eds), Energy Futures, De Gruyter, Berlin, 2023, pp. 125-168; F. Molnár, Smart Solutions for Securing the Power Supply of Smart Cities, in Interdisciplinary Description of Complex Systems, 21, 2023, pp. 161-167; T. Cioara, I. Anghel, I. Salomie, M. Antal et al., Exploiting data centres energy flexibility in smart cities: Business scenarios, in Information Sciences, 476, 2019, pp. 392-412; F. Niedermeyer, W. Duschl, T. Möller, H. de Meer, Increasing Data Centre Renewable Power Share Via Intelligent Smart City Power Control, in e-Energy ’15: Proceedings of the 2015 ACM Sixth International Conference on Future Energy Systems, pp. 241-247 etc. ↑
5. See D. Chernicoff, As SMRs Stumble, Will Microreactors Find a Home In the Data Center Industry?, https://www.datacenterfrontier.com/energy/article/33015713/as-smrs-stumble-will-microreactors-find-a-home-in-the-data-center-industry [accessed on 17^th December 2025]. ↑
6. See https://www.datacenterdynamics.com/en/news/bahnhof-wants-to-build-a-nuclear-power-station-for-its-new-stockholm-data-center/ [accessed on 17^th December 2025]. ↑
7. See https://www.datacenterdynamics.com/en/news/nano-and-blockfusion-to-deploy-nuclear-microreactors-at-niagara-falls-data-center/ [accessed on 17^th December 2025]. ↑
8. See https://www.theguardian.com/technology/2024/oct/15/google-buy-nuclear-power-ai-datacentres-kairos-power [accessed on 17^th December 2025]. ↑
9. See https://www.neimagazine.com/news/nano-partners-with-digihost-on-nuclear-powered-ai-data-centre/?cf-view [accessed on 20^th December 2024]. ↑
10. See S. Paul, M. Klimenka, F. Duarte, C. Crawford et al., When Cities Go Nuclear: Exploring the Applications of Nuclear Batteries Toward Energy Transformation, in Urban Science, 8, 2024, at pp. 226-246; A. Grishina, M. Chinnici, A. Kor, E. Rondeau et al., Data Center for Smart Cities: Energy and Sustainability Issue, in F. Pop, G. Neagu (eds), Big Data Platforms and Applications. Case Studies, Methods, Techniques, and Performance Evaluation, Springer Nature. Cham, 2021, at pp. 1-39. ↑
11. See G. Black, D. Shropshire, K. Araújo, A. van Heek, Prospects for Nuclear Microreactors: A Review of the Technology, Economics, and Regulatory Considerations, in Nuclear Technology, 209, 2023, pp. 16-17. ↑
12. For terminological clarification, see A. B. Frazier, R. O. Warrington, C. Friedrich et al., The miniaturization technologies: past, present, and future, in IEEE Transactions on Industrial Electronics, 42, 1995, pp. 423-430. ↑
13. See J. N. Pelton, S. Madry, Introduction to Small Satellites Revolution and Its Many Implications, in J. N. Pelton, S. Madry (eds), Handbook of Small Satellites Technology, Design, Manufacture, Applications, Economics and Regulation. Springer Nature, Cham, 2020, pp. 1-33. ↑
14. See A. Forganni, Legal Considerations on Space Commercialisation, in S. Lieberman, H. Athanasopoulos, T. Hoerber (eds), The Commercialisation of Space Politics, Economics and Ethics, Routledge, Cheltenham, 2023, pp. 211-227. ↑
15. See L. Cesari, J. Handrlica, A. Sandulli, Symposium on “Golden Age of European Space Regulation”, in The Lawyer Quarterly, 14, 2024, pp. 552-553. ↑
16. See G. Mastroianni, Il DDL Spazio italiano: le nuove governance, il dubbio sulla disciplina dei voli sub orbitali e l’allontanamento dal modello USA, in Quaderni AISDUE – Rivista quadrimestrale, 2, 2024, pp. 1-25. ↑
17. See L. Cesari, Developing an EU Space Law: the process of harmonising national regulations, McGill Institute of Air & Space Law, Montreal, 2024, available at https://www.mcgill.ca/iasl/article/developing-eu-space-law-process-harmonising-national-regulations [accessed on 17^th December 2025]. ↑
18. See OECD/NEA, Small Modular Reactor Dashboard. 2^nd edition, OECD, Paris, 2024, available at https://www.oecd-nea.org/jcms/pl_90816/the-nea-small-modular-reactor-dashboard-second-edition [accessed on 17^th December 2025]. ↑
19. Argentina, Belgium, Canada, China, Czech Republic, France, Indonesia, Japan, Myanmar, Philippines, Poland, Romania, Russia, Rwanda, Saudi Arabia, South Korea, Sweden, Ukraine and the United States of America. ↑
20. See J. P. Schlegel, P. K. Bhowmik, Small modular reactors, in J. Wang, S. Talabi, S. Bilbao y Leon (eds), Nuclear Power Reactor Designs, Academic Press, Cambridge, 2023, pp. 283-308. ↑
21. Cement, chemicals and petrochemicals, and steel industries. These industries are responsible for nearly 60 per cent of total industrial energy consumption and contribute approximately 70 per cent of industrial CO2 emissions. ↑
22. See C. Stenberg, Energy transitions and the future of nuclear energy: A case for small modular reactors, in Washington Journal of Environmental Law & Policy, 57, 2020, pp. 57-73. ↑
23. See A. Vaya Soler, The future of nuclear energy and small modular reactors, in T. Letcher (ed), Living with Climate Change, Elsevier, Amsterdam, 2023, pp. 465-512. ↑
24. See J. Vujić, R. Bergmann, R. Škoda, M. Miletić, Small modular reactors: Simpler, safer, cheaper?, in Energy, 45, 2012, pp. 288-295. ↑
25. See https://www.iaea.org/newscenter/news/what-are-small-modular-reactors-smrs [accessed on 17^th December 2025]. ↑
26. See R. Testoni, A. Bersano, S. Segantin, Review of nuclear microreactors, in Progress in Nuclear Energy, 138, 2021, article 103822. ↑
27. See IAEA (ed), Small Modular Reactors. Advances in SMR Developments 2024, IAEA, Vienna, 2024, p. 13. ↑
28. See https://www.energy.gov/ne/articles/what-nuclear-microreactor [accessed on 20^th December 2024]. ↑
29. See IAEA (ed), Small Modular Reactors. Advances in SMR Developments 2024, IAEA, Vienna, 2024, pp. 14-15. For a significantly updated overview of ongoing projects, see T. Lane, S. T. Revankar, Advances in technology, design and deployment of microreactors- a review, in Progress in Nuclear Energy, 178, 2025, article 105520. ↑
30. See https://westinghousenuclear.com/energy-systems/evinci-microreactor/ [accessed on 17^th December 2025]. ↑
31. See https://www.datacenterfrontier.com/energy/article/55232808/westinghouse-evinci-microreactor-could-yield-5-mw-of-nuclear-power-every-8-years-for-ai-data-centers [accessed on 17^th December 2025]. ↑
32. See https://nanonuclearenergy.com/microreactors/ [accessed on 17^th December 2025]. ↑
33. A pioneering project of a university microreactor is currently being realised at the Lappeenranta University of Technology in southeastern Finland. In 2022, this University signed a Memorandum of Understanding with the Seattle-based Ultra Safe Nuclear Corporation, aiming to deploy a microreactor as a research and test reactor in the city of Lappeenranta, which is the regional capital of South Karelia. ↑
34. See https://www.theguardian.com/technology/2024/oct/15/google-buy-nuclear-power-ai-datacentres-kairos-power [accessed on 17^th December 2025]. ↑
35. See R. Sam, T. Sainati, B. Hanson, R. Kay, Licensing small modular reactors: A state-of-the-art review of the challenges and barriers, in Progress in Nuclear Energy, 164, 2023, article 104859, p. 2. ↑
36. See K. Sexton Nick, The future of nuclear energy and the role of nuclear law, in Nuclear Law Bulletin, 2022, pp. 9-11. ↑
37. See Z. Zhang, C. Wang, K. Guo, S. Qui et al., Microreactors, in J. Wang, S. Talabi, S. Bilbao y Leon (eds), Nuclear Power Reactor Designs, Academic Press, Cambridge, 2023, pp. 309-347. ↑
38. See B. Newsad, Micro Nuclear Reactors Can Help Solve the Climate Crisis, in Environmental, Natural Resources & Energy Law Blog, Lewis & Clark Law School, available at https://www.lclark.edu/live/blogs/227-micro-nuclear-reactors-can-help-solve-the-climate [accessed on 17^th December 2025]. ↑
39. See H. Cook, The Law of Nuclear Energy, 3^rd edition, Sweet & Maxwell, London, 2022, pp. 410-412. ↑
40. Convention on Nuclear Safety, art. 7.2.ii. ↑
41. For further details, see A. Van Kalleveen, Applicability of the international nuclear legal framework to small modular reactors (SMRs). Preliminary Study, European Commission – Joint Research Centre, Brussels, 2022, p. 4. ↑
42. Council Directive 2009/71/Euratom of 25 June 2009 establishing a Community framework for the nuclear safety of nuclear installations, OJ L 172, 2.7.2009, pp. 18–22, art. 4.1.b. ↑
43. See R. Sam, T. Sainati, B. Hanson, R. Kay, Licensing small modular reactors: A state-of-the-art review of the challenges and barriers, in Progress in Nuclear Energy, pp. 2-6; T. Sainati, G. Locatelli, N. Brookes, Small Modular Reactors: Licensing constraints and the way forward, in Energy, 82, 2015, pp. 1092-1095. ↑
44. See J. Handrlica, M. Novotná, The feast of insignificance of small modular reactors in international nuclear law, in Czech Yearbook of Public & Private International Law, 12, 2021, pp. 327-328. ↑
45. For more details on the liability issues arising with respect to the small modular reactors, see V. J. H. Roland, Applicability of the existing nuclear liability conventions to different types of small modular reactors currently under development, in Nuclear Law Bulletin, 110, 2023, pp. 7-36. ↑
46. See J. R. Lovering, A Techno-Economic Evaluation of Microreactors for Off-Grid and Microgrid Applications, in Sustainable Cities and Society, 95, 2023, article 104620. ↑
47. Convention on Nuclear Safety, art. 7.2.iii. ↑
48. Ibid., art. 8.1. ↑
49. Directive 2009/71/Euratom, art. 4 and 5. ↑
50. See B. Zohuri, Nuclear Micro Reactors, Springer Nature, Cham, 2020, pp. 110-115. ↑
51. Joint Convention on the Safety of Spent Fuel Management and on the Safety of Radioactive Waste Management, Preamble at (xi). ↑
52. Council Directive 2011/70/Euratom of 19 July 2011 establishing a Community framework for the responsible and safe management of spent fuel and radioactive waste, art. 4.4. ↑
53. Joint Convention, Preamble at (xi). ↑
54. Council Directive 2011/70/Euratom, art. 4.4. ↑
55. See N. Prieto Serrano et al., SMR and AMR Radioactive Waste: A Comparative Legal Analysis, paper presented at the 25^th Nuclear Inter Jura Congress in Warsaw in November 2024 and available here: https://dise.org.pl/papers/S10_Nuria_Prieto-Serrano_Waste_from_SMR_Inter_Jura_Warsaw_2024_with_Annex_USA.pdf [accessed on 17^th December 2025]. ↑
56. See A. Larson, Is a Nuclear Reactor Headed to the Heart of Your City?, available at https://www.powermag.com/is-a-nuclear-reactor-headed-to-the-heart-of-your-city/ [accessed on 17^th December 2025]. ↑
57. The emergency planning zone (EPZ) is defined by the IAEA as «the precautionary action zone (PAZ) and the urgent protective action planning zone (UPZ)» See IAEA (ed), Preparedness and Response for a Nuclear or Radiological Emergency, in IAEA Safety Standards Series No. GSR. Part 7, IAEA, Vienna, 2015, p. 82. The precautionary action zone (PAZ) and the urgent protective action planning zone (UPZ) are defined in the same publication on p. 91 (PAZ) and p. 96 (UPZ). ↑
58. See https://sv.wikipedia.org/wiki/Hjorthagen [accessed on 17^th December 2025]. ↑
59. See D. Dalton, Underground Plants ‘Could Be Built In City Centres’, https://www.nucnet.org/news/underground-plants-could-be-built-in-city-centres-11-3-2024. ↑
60. See D. Shropshire, G. Black, K. Araújo, Global Market Analysis of Microreactors, Idaho National Laboratory, Idaho Falls, 2021, pp. 61-86. ↑
61. For a much more detailed study on this problem, see T. P. Kuipers, Developing nuclear security related legislative guarantees in licensing mobile Small Modular Reactors, Master Thesis, Department of Business and Management at the University of Applied Sciences Brandenburg, 2020. ↑
62. Nanosatellites are small satellites that typically weigh less than 10 kilograms and measure from 10 centimetres to 10 x 10 x 11.35 centimetres in size. They provide a range of applications, including communications, Earth observation, remote sensing, and scientific research. ↑
63. Decreto-Lei n.º 16/2019, de 22 de janeiro. ↑
64. Ibid., art. 6.1.a. ↑
65. Ibid., art. 6.1.b. ↑
66. See F. Ekinci, M. S. Guzel, K. Acici, T. Asuroglu, The Future of Microreactors. Technological Advantages, Economic Challenges, and Innovative Licensing Solutions, in Applied Sciences, 14, 2024, article 6673. ↑
67. See https://www.congress.gov/bill/118th-congress/senate-bill/1111 [accessed on 17^th December 2025]. ↑
68. See ADVANCE Act of 2024, Sec. 2.4. ↑
69. Ibid. Sec. 101. ↑
70. Ibid. Sec. 101.b. ↑
71. Ibid. Sec. 203.c. ↑
72. Ibid. Sec. 206. ↑
73. On 1 January 2024, new rules for when nuclear power plant reactors may be built took effect in Sweden, allowing new reactors to be established in areas where nuclear power plants have previously not been located. This will virtually enable the construction of microreactors in the future. See https://www.loc.gov/item/global-legal-monitor/2024-01-29/sweden-new-rules-for-nuclear-power-plant-reactors-take-effect/ [accessed on 17^th December 2025]. ↑
74. See P. Gorzkowski, Legal barriers to the deployment of SMR and ANT reactors in the European Union. Is the Euratom Treaty sufficient?, paper presented at the 25^th Nuclear Inter Jura Congress in Warsaw in November 2024 and available here: https://dise.org.pl/papers/S13_Przemyslaw-Gorzkowski.pdf [accessed on 17^th December 2025]. ↑
75. See J. Handrlica, Nuclear law revisited as an academic discipline, in The Journal of World Energy Law & Business, 12, 2019, pp. 52–68. ↑
76. See C. Stoiber, A. Baer, N. Pelzer, W. Tonhauser, Handbook on Nuclear Law, IAEA, Vienna, 2003, p. 5. ↑
77. Ibid. p. 7. ↑
78. Ibid. p. 8. ↑