M1L11: Nuclear energy-I

This lecture marks the end of our first module, which is based on energy security. The next module shall be based on Biotechnology. This entire lecture will be divided into two parts, the first one will deal with fission energy and the second one will deal with fusion energy,

We return back to our original chart. Check out whatever topics have been covered in previous lectures.

So, if you look closely, each and every topic mentioned here is over except one that is nuclear.

Now, Nuclear is a very clean fuel. It doesn’t release CO₂ emissions, nor does it produce fly ash or particulate matter.

So, if India wants to reduce CO₂ emissions that it has pledged in INDCs (33% reduction compared to 2005 levels by 2030), is nuclear a good option? Answer is yes, provided all the safeguards are followed.

The world has already witnessed the horrific effects of nuclear radiation. Even today, we are witnessing multiple cases of abuse of nuclear fuels by nations, that claim to be champion of human rights. For e.g. back in the year 1991 during the gulf war, the United States had used depleted Uranium in its antitank missiles. This depleted Uranium comes out of nuclear chambers. When used as a projectile, it heats up very fast due to friction it encounters with air. The amount of heat, it generates, is enough to melt the armour of the tanks. Today, it is widely witnessed that the new born kids of the poor Iraqi civilians are carrying defects and mutations as this depleted Uranium particles are getting mixed with air. Similar cases have also been witnessed in Afghanistan which reveals that Americans have used depleted Uranium there as well.

In India too, multiple cases are continuously found about people born with mutation in Jadugowda, Narwapahar and Bhatin area. The mines in these areas is owned and managed by UCIL, Uranium corporation of India ltd.

So, now let us turn our faces towards the technological aspect of nuclear technology. As discussed earlier, there is a hidden cost attached to fossil fuels, despite the fact that, fossil fuels are cheaper compared to renewable and nuclear energy. Moreover, the estimated coal deposits in India is ~ 270 billion tonnes which is approx... 8% of the world coal reserves. This amount is first of all, of inferior quality (because Indian coal is mostly lignite) are far from being adequate to achieve the ambitious target in terms of power generation.

Enrichment of uranium fuel

1.    Natural U isotopic composition is 0.7 % fissile U-235 and the rest is U-238. U-235 is the actually required fuel for Nuclear reactor

2.    In order to use it as a nuclear fuel, we need to enrich this to optimum levels. This is done using centrifuges to increase content of U-235.

India is in talks with Uzbekistan to create uranium reserve (NDTV Sep. 24, 2017)

India is engaging with various countries, including Uzbekistan, to procure nuclear fuel as part of its plan to create a strategic uranium reserve to ensure long-term security. The plan is to have a stockpile of nuclear fuel for its strategic uranium reserve that can sustain the country's reactors for the next five years so that they do not stop functioning because of the lack of uranium.

The estimated natural deposits of these elements in India are:

1.         Natural Uranium deposits - ~70,000 tonnes

2.         Thorium deposits - ~ 3,60,000 tonnes

In India, it is found in Singhbhum shear zone (Jharkhand)

1.    Cuddapah basin (Andhra Pradesh)

2.    Mahadek basin (Meghalaya)

3.    Bhima basin (Karnataka)

4.    Delhi Supergroup of rocks (Rajasthan).

So, how do we use Nuclear Energy?

In case of nuclear energy, we try to use heavy elements like Uranium 235, Plutonium 239 and Uranium 233. Apart from that, we can also use americium and neptunium as fissile elements but they are very expensive and difficult to manage. Highly advanced and technologically capable nations like United States are only capable of working with it.

Nuclear reactors generate energy through fission, the process by which an atomic nucleus splits into two or more smaller nuclei. During fission, a small amount of mass is converted into energy, which can be used to power a generator to create electricity.

In order to harness this energy, a controlled chain reaction is required for fission to take place. When a uranium nucleus in a reactor splits, it produces two or more neutrons that can then be absorbed by other nuclei, causing them to undergo fission as well. More neutrons are released in turn and continuous fission is achieved.

Neutrons produced by fission have high energies and move extremely quickly. These so-called fast neutrons do not cause fission as efficiently as slower moving ones. In order to slow them, we use a process known as moderation. A liquid or gas moderator, commonly heavy water or helium, cools the neutrons and slows them to optimum energies for causing fission. These slower neutrons are also called thermal neutrons because they are brought to the same temperature as the surrounding coolant.

The other components of nuclear reactor include

1.    Coolant

2.    Pump

3.    Control rod

4.    Enriched nuclear fuel

Nuclear reactors can be divided into following types. Majority of India’ nuclear reactors are Heavy water reactors.

Types of Nuclear reactor

(1) Boiling Water Reactor

In the boiling water reactor, the same water loop serves as moderator, coolant for the core, and steam source for the turbine. In the boiling water reactor (BWR), the water which passes over the reactor core to act as moderator and coolant is also the steam source for the turbine. The disadvantage of this is that any fuel leak might make the water radioactive and that radioactivity would reach the turbine and the rest of the loop.

(2) Pressurized Water Reactor

In the pressurized water reactor, the water which flows through the reactor core is isolated from the turbine. In the pressurized water reactor (PWR), the water which passes over the reactor core to act as moderator and coolant does not flow to the turbine, but is contained in a pressurized primary loop. The primary loop water produces steam in the secondary loop which drives the turbine. The obvious advantage to this is that a fuel leak in the core would not pass any radioactive contaminants to the turbine and condenser.

(3) Liquid-Metal Fast-Breeder Reactor

In the LMFBR, the fission reaction produces heat to run the turbine while at the same time breeding plutonium fuel for the reactor.

To understand this concept, lets cover the basics

Elements used in nuclear fission are divided into two categories: Fissile and Fertile

The fissile group of elements have low radius of neutron capture cloud while fertile group of elements have larger radius of neutron capture cloud. This means, that the neutrons moving towards fissile elements require to be slowed down and guided towards the nucleus, so that they do not miss the target. These elements are Uranium-233, Uranium-235 and Plutonium-239.

In the case of fertile elements, since the atom has a larger radius of neutron capture cloud, the moving neutron can be captured even if it is moving at a farther distance from itself.  

So, what inference do we get out of this? In case of fertile elements, the neutrons need to be slowed down so that it becomes easy to guide and navigate it. This requires the use of moderator to carry forward chain reaction from first generation to second generation and later. The neutrons slowed down using the moderator are called as slow neutrons.

On the other hand, in case of fissile elements, the neutrons can be captured even if they are moving fast while they are at a considerable distance away from the nucleus. When they absorb a neutron, they do not break themselves. They rather accommodate one neutron and do a transition to higher order elements which are fissile. This can be done even without a moderator using fast neutrons. These elements are Thorium-232 and Uranium -238. When they absorb the neutron, Th-232 makes a transition to U-233 and Uranium-238 makes a transition to Pu-239. Recall the fact that both, U-233 and Pu-239 are fissile, which means we just bred a new fuel using Th-232 and U-238. (In reality, U-238 first captures a neutron, forms U-239 and then undergoes two beta decays to form Pu-239).

Thus, in case of Liquid metal, fast breeder reactor, we use Uranium 238 to breed Plutonium 239 using fast neutrons. This plutonium can be used a fuel for later stages. (Since plutonium-239 is one among the three fissile elements that can undergo chain reaction. The other two are Uranium-233 and Uranium-235)

Indian 3 stage Nuclear Power Generation Program

STAGE 1 » Pressurized Heavy Water Reactor

STAGE 2 » Fast Breeder Reactor

STAGE 3 » Breeder Reactor

STAGE 1 » Pressurized Heavy Water Reactor using

1.    Natural UO₂ as fuel matrix

2.    Heavy water as moderator and coolant

STAGE 2 » Fast Breeder Reactor

Recall the fact, that a fast reactor doesn’t need a moderator, so that its neutrons remain high-energy and move fast. Fast neutrons are ideal for plutonium production because they are easily absorbed by U-238 to create Pu-239. This is why many breeder reactors are also fast reactors. It only uses a coolant such as liquid sodium to maintain the walls of the reactor below its melting point, to avoid the meltdown of the walls of the nuclear reactor.

1.    Using Pu-239 obtained from the first stage as the main fissile element in the FBR.

2.    Blanket of U-238 surrounding the fuel core will undergo nuclear transmutation to produce fresh Pu-239 as more and more Pu-239 is consumed during the operation.

3.    Blanket of Th-232 around FBR core also undergoes neutron capture forming U-233.

4.    U-233 is the nuclear reactor fuel for 3^rd stage of India’s Nuclear Power Programme.

STAGE 3 » Breeder Reactor

1.    U-233 fuelled breeder reactors will have a Th-232 blanket around the U-233 reactor core.

2.    This will generate more U-233 as the reactor goes operational

3.    Thus, resulting in the production of more and more U-233 fuel from the Th-232 blanket

India becomes the sixth nation having the technology to build and operate a Fast breeder Thorium Reactor besides USA, UK, France, Japan and the then USSR.

Why few countries are able to master this technology?

Uranium-233 has a very high gamma signature. Which means it is very difficult to handle. Most of these countries mentioned above, have shut down their research on using U-233 for the same reason. This itself shows, how much it is challenging to manage Uranium-233 and then later on use it as a fuel.

So, is it possible to divert Th-232 to make nuclear bombs? Answer is No. Since, Th-232 is fertile, it needs to be first converted to U-233, to be used as a bomb in true sense. But as mentioned earlier, since the Gamma signature of U-233 is very high, it will get immediately detected in radars or satellites. Thus, when it comes to nukes, Thorium is anti-proliferation.

India is lucky to possess the highest deposits of Thorium in the world. Now we have the technology and we also have the fuel. But can we export this? Doubtful, since India is not a full-time member of NSG yet.

India's thorium is mostly located in a contiguous belt of eastern coastal states as placer sands. As per records of the year 2016, monazite reserve estimates:

1.    Andhra Pradesh (31%)

2.    Tamil Nadu (21%)

3.    Odisha (20%)

4.    Kerala (16%)

5.    West Bengal (10%)

6.    Jharkhand (2%)

After Fukushima disaster, the world needs a technology that is full-proof. Thorium can be a solution to it. However, it should not be neglected that fourth-generation reactors are now better equipped to tackle challenges and the Chinese have also matured a new form of nuclear engineering technology known as graphite pebble bed reactors, that promises to be completely meltdown proof.

What happened with Iran?

In the year, 2002, The US intelligence had discovered through the Iranian prisoners who were sent to exile, that Iran has built a vast uranium enrichment plant at Natanz & a heavy water plant at Arak without informing the United Nations. The existence of sites at Natanz & Arak is confirmed by satellite photographs shown on US television. The US accuses Tehran of "across-the-board pursuit of weapons of mass destruction". Iran agrees to inspections by the International Atomic Energy Authority (IAEA). 

Role of IAEA (International atomic energy agency) The main functions of the IAEA are to: encourage and assist research, development and practical application of atomic energy for peaceful uses throughout the world; establish and administer safeguards designed to ensure that such activity assisted by the Agency is not used to further any military purpose; apply safeguards to relevant activities at the request of Member States; apply, under the Nuclear Non-Proliferation Treaty (NPT) and other international treaties, mandatory comprehensive safeguards in non-nuclear weapon States (NNWS) Parties to such treaties.

In the year 2003, Iranian President Mohammed Khatami reveals that Iran has unearthed uranium deposits & announces plans to develop a nuclear fuel cycle. IAEA chief Mohammed ElBaradei travels to Iran with a team of inspectors to begin probing Tehran's nuclear plans. Mr. ElBaradei found that Iran possessed advanced designs of uranium-enriching centrifuges, raising further concerns about Iran’s nuclear intentions. He accused Iran of not revealing the extent of its nuclear work & urges leaders to sign up for more intrusive inspections since the traces of highly enriched weapons-grade uranium (U-246) were found at Natanz. IAEA report also mentioned that Iran experimented with polonium-210, which can be used to trigger the chain reaction in a nuclear bomb. Iran did not explain the experiments but agrees to suspend enrichment. However, later on, an independent investigation mentions that there is no evidence that Iran was working on a secret nuclear weapons program. It concluded that traces of bomb-grade uranium in Iran's nuclear facilities came from contaminated Pakistani equipment that Iran had got from them & not Iranian activities. Similarly, the study conducted by the International Institute for Strategic Studies also concluded that Iran was several years away from acquiring a nuclear weapons capability.

The U.S. however dismissed the report. After meeting French, German & U.K. foreign ministers, Tehran agrees to stop producing enriched uranium & formally decides to sign the Additional Protocol. However, no evidence is produced to confirm the end of enrichment.  (Additional Protocol de-facto gives legitimacy to a country that possesses Nuclear Weapons).

The 2015 Nuclear Deal (JCPOA Joint Comprehensive Plan of Action)

Iranian aspirations to become a regional power, may be confirmed by the fact that Iran had been trying to become a nuclear power since the times of the Shah Pahlavi, who launched a nuclear program in 1967. Since then, Iran has had the same clear objective of becoming a member of the “elite nuclear club”. However, a series of tough sanctions from the UN Security Council (UNSC), the European Union (EU), & the USA have all affected the development of the nuclear program, the Iranian economy, & population, mainly since 2006. The Iranians achieved their objective, although at a significant compromise of their nuclear program, when P5 + 1 (‘P’ members of UNSC & Germany) brokered a deal with Iran, later to be known as JCPOA.

The prolonged negotiations between P5+1, resulted in the signature of a Joint Comprehensive Plan of Action (JCPOA) on April 2, 2015, in which Iran was guaranteed

the right to a full cycle of nuclear development & the promise of the lifting of sanctions, in exchange for suspending its uranium enrichment activities, reducing the number of centrifuges, diluting the already enriched uranium, reducing its stockpile, & agreeing to complete transparency & supervision of the whole program for a 25-year period. Despite the serious bilateral & multilateral engagement in the nuclear negotiations that ended with the final JCPOA, the reception in the Middle East & Gulf region was not positive. Israel & Saudi Arabia never wanted the United States to go ahead with the deal. This concern was evident at the GCC summit held in Doha on December 7, 2014, when the six members decided to create a joint naval force to protect the Gulf waters, demonstrating their concern regarding Iran becoming a nuclear power & regional hegemon. Iran’s GCC neighbors & Israel considered that with the nuclear deal, Iran would be much more influential & destabilizing than ever before.

On May 8, 2018, United States President, Donald Trump abrogated the JCPOA Nuclear deal with Iran & has gone ahead to reimpose sanctions on the basis, that JCPOA doesn’t involve Iran’ missile program. Most of these measures are primary sanctions, & comprise of asset freezes, trade embargoes & prohibition on US citizens & companies from engaging with Iran. However, some of these measures impose “extra territorial” or “secondary” sanctions through CAATSA i.e., penalize third country firms that are involved in Iran’s energy sector. These can potentially penalize Indian companies with exposure to US financial institutions & prohibit loans from US financial entities. Iran has made it clear that if the rest of the P5+1 keep their sanctions off, Iran may decide to continue to adhere to the deal's restrictions even after the US pullout.

Implications of Nuclear Iran on India

A nuclear Iran posing an existential threat to Israel & a security risk to other Gulf states will result in greater instability in the Middle East, something that India can ill afford, given its dependence on the Gulf for resources. Many of the Arab states in the Gulf have unresolved disputes with Iran, & they are loath to see Iranian hegemony over the region.

The Gulf Cooperation Council, led by Saudi Arabia, has made its concern about a nuclear Iran clear by announcing its plan to develop a joint nuclear power program. Iran’s growing role in Iraq is generating apprehension in many Gulf states with significant Shia minorities. An unstable Middle East is not in India’s interest since thousands of people work there & support Indian economy through remittances.

There is a more fundamental question India confronts in dealing with the Iranian nuclear issue. As a responsible nuclear power, something India prides itself in, what is its role in the new global nuclear order? While India developed its own nuclear program outside the confines of the NPT, Iran’s nuclear program is progressing even as it remains a NPT member. It refuses to answer many questions regarding its nuclear program posed by the IAEA & by major powers. Even Russia & China have joined the West in seeking explanations from Iran. In such a scenario, how can India take a position that goes against the will of the UN? Ironically, many in India who today want their country to support Iran’s nuclear plans are also the biggest proponents of multilateralism & the UN.