India is taking steps for the development of small modular reactors (SMR) with up to 300 megawatts (MW) capacity to fulfill the country’s commitments towards clean energy transition, according to the Indian Atomic Energy Minister Jitendra Singh.
These commitments, as announced by India at the COP26 climate change talks in Glasgow last year, include achieving net zero emissions latest by 2070 and reducing its carbon emissions until 2030 by a billion tonnes.
At a workshop on SMRs held last month in the capital New Delhi, the Atomic Energy Minister said that nuclear energy in terms of reliable base load power can play a big role in the country’s de-carbonisation strategy. “The role of nuclear energy will be critical for the clean energy transition of not just India but for the entire world”, Singh said.
Both the continuing concerns about climate change and the ongoing crisis in the energy market caused by rising fuel prices have led to renewed interest globally in nuclear as a source of clean energy, while some countries like Japan and South Korea have even announced a reversal of their earlier policy of not building new nuclear power plants (NPPs).
This development has, naturally, put the focus also on the technology of small modular reactors, which, as Minister Singh described them, are flexible in design and require a smaller footprint.
“Being mobile and agile technology, SMRs can be factory-built unlike the conventional nuclear reactors that are built on–site. Thus, SMRs offer significant savings in cost and construction time”, he said at the workshop organised by India’s Department of Atomic Energy (DAE).
SMRs are advanced nuclear reactors that have a power capacity of up to 300 MW. They are a fraction of the size of conventional reactors, as well as modular, making it possible for systems and components to be factory-manufactured and transported as a unit to a location for installation.
SMRs offer many advantages, such as relatively small physical footprints, reduced capital investment, ability to be sited in locations not possible for larger nuclear plants, and provisions for incremental power additions.
Almost all Asian countries that have embarked on civilian nuclear energy programmes have been guided by the major concern of providing energy security for their populations, reduce dependence on fossil fuels in the context of climate change, as well as the cost of nuclear technology, which has become an important factor as prices have risen sharply in the last decades.
What adds to the cost of conventional nuclear power plants in the 700-1000 MW category are long construction periods and related delays, parting from the initial requirement of large land areas for setting up such NPPs.
In such a context, SMRs provide an attractive proposition, foremost from the cost aspect, while addressing other related concerns of safety, the issue of nuclear waste and that of the large land requirement for NPPs. Moreover, SMRs can also help address the electricity requirements of far-flung communities that are dispersed over the hinterlands of rural Asia. SMR construction can be carried out by small utilities and are much easier to operate and maintain in remote areas.
According to extant research, SMRs provide increased safety by providing, among others, more efficient passive heat removal from the reactor vessel and greater quality control. Lower thermal power of the SMR reactor core, compact architecture, and employment of passive concepts have the potential for enhanced safety and security compared to earlier designs and large commercial reactors. The passive safety systems are a very important safety feature in the SMR. As a result, there is less reliance on active safety systems, additional pumps and AC power in case of an accident.
These also have much lower land requirements, lesser delays in construction and involve significantly smaller displacement and rehabilitation of population displaced through land acquisition that would otherwise be necessary for conventional NPPs.
The most compelling argument for the suitability of SMRs for Asian nations is from the financial point of view of lower capital requirement and the attendant potential of permitting tighter control over the three key related aspects of operation, maintenance and safety.
The SMRs’ modular nature allows for scaling up capacity by adding units according to demand. According to the International Atomic Energy Agency (IAEA), SMRs are also better suited to operate flexibly in tandem with variable renewable energy sources such as wind and solar in a hybrid energy system, as well as for non-electric applications such as seawater desalination, district heating and hydrogen production.
“This is the decade of SMR demonstrations, which could potentially determine front runners for the expected economy of series production. There is high level of innovation”, says IAEA’s head of planning and economic studies Henri Paillere.
According to Sunil Ganju, who is Member of the Nuclear Controls and Planning Wing in the DAE, the driving forces for introducing SMRs are the possibility of their “incremental deployment” in a context where “incremental demand can be closely matched with moderate financial commitment, especially for countries with smaller electricity grids”. On the safety aspect, he said “the lower core power density of SMRs and the large volume of water in the reactor power vessel delays all accident progression”.
In an interview with Nuclear Asia, former Principal Adviser, Department of Atomic Energy (DAE), and former Vice Chancellor, Homi Bhabha National Institute, Ravi Grover, provided his perspective on the development of SMRs in the Indian context by saying that India can make small modular reactors as it has the talent pool. He said that India has already built a small reactor that powers its nuclear submarine INS Arihant.
Grover noted that in its initial stages, the Indian nuclear programme used small reactors of less than 300 MW capacity that were developed indigenously, and that Indian industry makes a substantial contribution in the manufacture of most reactors in India.
“Indian industry has the capacity to make SMRs, if one considers that companies like the state-run BHEL, as well as L&T and Walchandnagar Industries in the private sector play a major role in reactor manufacture in India”, Grover said, pointing out that India’s first indigenously made 700 MW reactor at Kakrapar in Gujarat was connected to the grid in 2021.
“The mainstay of our nuclear programme started with reactors with a capacity of 220 MW, which was subsequently increased to 540 MW, and now we have manufactured this 700 MW optimal capacity reactor”, Grover said.
“More than 70 commercial SMR designs are being developed around the world, and we have to decide which ones best suit our purposes. It is a question of a policy decision, and the government has to give directions in this regard”, he added.
For instance, the small thorium-based high temperature gas-cooled reactors (STGRs) of 20-40 MW sizes are considered an appropriate choice for India given the country’s significant reserves of thorium. The IAEA has highlighted the safety features of these reactors.
In view of the incipient stage of work on SMRs in India, Grover feels that the commercial development of such reactors in the country is still around 10-15 years away. “The move to develop SMRs is a good one and in the right direction, but we are still in the beginnings.Lots of work is required to establish their techno-commercial viability”, Grover told Nuclear Asia.
According to Grover, the regulatory aspect of SMRs is still work in progress globally, while one of the very important barriers is the licensing of new reactor designs. Historically, the licensing process was developed for large commercial reactors, while the licensing process for new reactor designs is a lengthy and costly exercise.
Chancellor of the Homi Bhabha National Institute and former Chairman of India’s Atomic Energy Commission (AEC) Anil Kakodkar told Nuclear Asia that the ongoing decarbonisation efforts globally have helped create a larger market for SMRs.
Regarding the Indian situation, Kakodkar said that since India’s energy needs are continually on the rise, the country needs big capacity addition and, thus, large nuclear reactors will continue to be relevant in India.
“Large reactors are important to increase the share of nuclear energy in the country’s overall power mix. However, aging plants need to be replaced, and a large number of coal plants will be retired, so there is the possibility of setting up SMRs at the sites of such retiring thermal plants”, Kakodkar said.
“Locating SMRs at the location of these retiring coal plants will also satisfy the regulatory requirements for setting up SMRs, because the infrastructure is already available”, he added.
In line with India’s target to reduce carbon emissions, it is estimated that most of its coal-fuelled thermal power plants would be retired by 2050.
Noting that India already possesses the capability to build small reactors as demonstrated through the light water reactor powering its nuclear submarine, Kakodkar said SMRs should be built indigenously working on the “Integral”-type design in which the major components are all placed inside a single reactor pressure vessel.
Kakodkar also said that there is no unanimity of opinion as regards the cost benefit of SMRs over that of large reactors. Most economic benefits, especially lower capital cost, stated are valid for n-th unit produced. Large-scale production of SMRs and initial orders for tens of units is required to achieve these economic benefits.
“In this case, we have to consider the per megawatt cost, or the tariff, which will be much higher in case of the initial reactors, and which will only reduce after a certain number of reactors are set up”, he said.
“Only repetitive orders will bring down costs, but that would take some time to happen”, he added.
Kakodkar is of the opinion that SMR designs in India should be jointly developed by the Mumbai-based Bhabha Atomic Research Centre (BARC) and the country’s largest power generator, the state-run NTPC, which could utilise the sites and infrastructure of the retiring thermal power plants.
Citing industry sources, media in India reported earlier this month that NTPC is planning to build a massive nuclear fleet and aims to install 20 to 30 gigawatts (GW) of nuclear capacity by 2040. The company, which generates 90 percent of its power from fossil fuels, has announced that it will construct SMRs as well as conventional pressurised water reactors (PWRs).