Neutron economics I

We all have misconceptions about various things, but their potential for harm is not more pronounced than it is in the case of nuclear power generation. In fact, the momentum at which the subject is gaining relevance today practically mandates that ignorance, too, can cause just as much harm. Therefore, it is important to know what goes on inside a nuclear reactor due to which it produces power, what are the different kinds of fuel used in such power plants, what the scientific principles are that dictate the process flow, and so forth.

[caption id="attachment_20602" align="aligncenter" width="600" caption="Sources: Energy Information Administration (EIA), International Energy Annual 2004 (May-July, 2006); EIA, System for the Analysis of Global markets (2007)."][/caption]

Nuclear power plants, or NPPs, are currently positioned within the proliferation stage: the threat of fossil fuel exhaustion is imminent and very real, and because of the lack of research invested in the development of plants that consume renewable energy, there approaches a developmental rupture in the future, a gap signifying the paucity of energy to sustain growth as well as the inability of forthcoming generations to comfortably define it. In light of such possibilities, nuclear power provides a suitable resource because of the following reasons.

1. Nuclear fuel could be considered to be yet under-exploited; even though reserves of usable uranium are running out, vast quantities of thorium and its isotopes await mining. However, it should be noted that only certain isotopes can be used for fuel, and in order to obtain a few grams of them, whole quintals will have to be mined and refined.


2. A few grams of the enriched isotope can deliver energy worth hundreds of tons of coal. At the same time, the undermining consequence is that the design of the power plant has to be such that it can withstand the generation of such amounts of energy in a matter of seconds.


3. A nuclear fusion reaction, which hasn't yet been deployed in the capacity of power generation, is more than one-million times stronger than a corresponding fission reaction, and produces no nuclear waste (theoretically). However, the engagement of such options has been delayed worldwide not by the costs involved but by the technology required to instigate and sustain such reactions.

 

[caption id="attachment_20595" align="aligncenter" width="600" caption="The sun is essentially a nuclear fusion powerhouse."][/caption]

I am not writing to clarify which side of the debate (nuclear v. non-nuclear) I lie on but only to highlight the simple concepts and procedures that sustain any interest on the widespread use of NPPs. Let's begin with the fuel cycle.

 

Every atom (except hydrogen's) contains a nucleus that, in turn, contains protons and neutrons in some number. More often than not, the difference between the number of protons and the number of neutrons is 0 or 1. The protons have a positive charge, are each about 1,800 times times heavier than an electron, and are bound to the neutrons by the strongest natural force: the nuclear force. During a fission reaction, it is the sundering of this bond that yields the gargantuan amounts of energy. The electrons in the atom exist around the nucleus at multiple energy levels, which are called so because all electrons in the same level have the same amount of potential energy.

 

To set off a nuclear reaction, i.e., to break up the nucleus, the trick is to make it heavy and, thus, unstable, like a 10-kilogram dumbbell with a central bar made of straw. To make it heavier, a suitable particle has to be forced into the nucleus. Such force is necessary because of two reasons.

1. The protons and neutrons are both heavy particles. Forcing a much-lighter electron in would have no appreciable effect on the total mass of the nucleus.


2. The protons are positively-charged, which rules out the option of forcing extra protons into the nucleus because of the Coloumbic, or electric, repelling force.

The obvious conclusion is the use of a neutron. However, not all neutrons can be used because it is necessary that the nuclear trap the neutron, become heavier and start disintegrating instead of having the neutron zip past with no useful effect. Such slowed neutrons are called thermal neutrons, and when these thermal neutrons are captured by nuclei, the nuclei become what are called isotopes of their original form.

 

[caption id="attachment_20596" align="aligncenter" width="600" caption="Uranium oxide"][/caption]

Now, in the event of a neutron capture, the chances of fission reactions occurring is not 100%: the nucleus may decide to whine away the excess mass through transmutation processes called alpha- and beta-decays. Having detailed as much, it becomes much easier to understand the working of a nuclear reactor.

1. A reactor core is readied where the nuclear reaction can take place in a controllable environment.


2. Enriched fuel is compacted in the shape of rods and inserted into the reactor core. The more the extent of insertion, the more nuclei are available for a fission reaction.


3. An adjacent chamber is flooded with heavy water and a source of neutrons is placed in it. (The molecular formula for water is H2O, which means each molecule contains two atoms of hydrogen. When these atoms are replaced by an isotope of hydrogen called deuterium, the resulting compound is called deuterium hydroxide or heavy water.)


4. At a suitable position within this arrangement, a provision for control rods is provided. Made of compounds of boron or cadmium, these rods, depending on the extent of their penetration into the chamber, are used to absorb excess neutrons in the event of their proliferation.


5. Voluminous ducts containing a coolant are coiled around the core to remove excess heat. In this case, let's assume the core is water-cooled.


6. When the reactor is ready, the control rods are fully retracted and the neutron source is allowed to generate fast neutrons.


7. These fast neutrons are slowed down upon collision with the surrounding heavy water molecules and become thermal neutrons.


8. The thermal neutrons are fed into the reactor core, where they are absorbed by the nuclei in the fuel rods.


9. A certain proportion of the nuclei begin the fissioning process, releasing massive quantities of kinetic energy, gamma radiation and more neutrons.


10. The kinetic energy manifests as an extremely high temperature within the reactor core.


11. The power plant's pumps are switched on and the water begins to flow in the coiled duct, across which heat is conducted and the water turns to steam. Consequently, the core cools down.


12. The steam is passed through a throttle that converts its pressure energy into kinetic energy, i.e., accelerates the steam into a jet that is guided onto the blades of a turbine that generates power.


13. Meanwhile, in the reactor core, even more neutrons are now available that at the start of the reaction because of the nuclear fission reactions that have already occurred.


14. To keep from all these neutrons causing nuclear havoc, the control rods are inserted enough to keep the rate of reactions tractable.


15. The available neutrons then continue to propagate the fission process with the remaining fuel.


16. The steam, after striking the blades of the turbine, slows down and is collected in a condenser. The vapor is then cooled, compressed and fed once more into the coiled ducts.

This is the nuclear fission process that occurs when a sufficiently enriched isotope is the fuel. Not all isotopes can be used in an NPP for power generation. They must meet certain requirements. For example, U-235 is used because its fission products can be handled to some extent, because the required technology to control its fission reaction exists, and because isotopic uranium is available in nature.

 

Once a neutron has been captured, the U-235 nucleus transmutes to a U-236 nucleus and becomes highly unstable. Because of the excess energy causing the instability, it begins to oscillate and eventually "comes apart", as a result of which the nuclear force breaks down and releases a massive amount of energy. If we assume that the U-235 nucleus was at zero-energy at the beginning and if the incoming thermal neutron had an energy of 1 electron-volt (eV), the resulting explosion releases somewhere around 215 mega-electron-volt (MeV): a jump of 215 million orders. Of this output, 168 MeV is in the form of kinetic energy, 17-26 MeV of gamma rays, 12 MeV of neutrons, 8 MeV of beta particles and the remaining of other fission products.

 

As stated earlier, the chances of a fission reaction occurring are not 100%, and when it doesn't happen, a process called beta decay takes its place. Note the emission of beta particles in a fission reaction: these particle-groups are of two kinds.

1. Negative beta decay: electron + electron anti-neutrino


2. Positive beta decay: positron + electron neutrino

(A positron is the anti-particle of the electron, i.e., it weighs the same as an electron and has all its properties, except for a +1 electrical charge instead of the electron's -1.)

When beta decay is said to occur, only positive or negative beta decay occurs; not both. Now, when a neutrino/anti-neutrino strikes a positively charged nucleus, the collision in question can occur only when a weak force comes into being between the neutrino and the nucleus. This weak force is mediated by a particle called the Z boson, which is an extremely heavy particle. To lose this temporarily gained excess mass/energy, the nucleus beta decays once more to become electrically neutral.

 

[caption id="attachment_20599" align="aligncenter" width="502" caption="Either Ce-173 or Sr-90 placed on a sheet of Alomogordo glass in the presence of a magnetic field emits beta particles, visible as feeble curves on the sheet."][/caption]

The beta decay process is important in reactors that use thorium-232 as nuclear fuel. When a Th-232 nucleus captures a thermal neutron, it undergoes fission, emits some gamma rays, and transmutes to Th-233. Next, Th-233 undergoes negative beta decay to become Pa-233 (protactinium), which beta decays once more to yield U-233. This isotope of uranium then captures a neutron, undergoes fission, releases two more neutrons, and becomes U-232. Now, U-232 is extremely radioactive (it is a strong emitter of gamma rays) and its formation is the principle disadvantage of employing a Th-232 nuclear fission cycle.

 

Therewith concludes the discussion on the principles of a nuclear fission reaction.

Neutron economics I

We all have misconceptions about various things, but their potential for harm is not more pronounced than it is in the case of nuclear power generation. In fact, the momentum at which the subject is gaining relevance today practically mandates that ignorance, too, can cause just as much harm. Therefore, it is important to know what goes on inside a nuclear reactor due to which it produces power, what are the different kinds of fuel used in such power plants, what the scientific principles are that dictate the process flow, and so forth.

[caption id="attachment_20602" align="aligncenter" width="600" caption="Sources: Energy Information Administration (EIA), International Energy Annual 2004 (May-July, 2006); EIA, System for the Analysis of Global markets (2007)."][/caption]

Nuclear power plants, or NPPs, are currently positioned within the proliferation stage: the threat of fossil fuel exhaustion is imminent and very real, and because of the lack of research invested in the development of plants that consume renewable energy, there approaches a developmental rupture in the future, a gap signifying the paucity of energy to sustain growth as well as the inability of forthcoming generations to comfortably define it. In light of such possibilities, nuclear power provides a suitable resource because of the following reasons.

1. Nuclear fuel could be considered to be yet under-exploited; even though reserves of usable uranium are running out, vast quantities of thorium and its isotopes await mining. However, it should be noted that only certain isotopes can be used for fuel, and in order to obtain a few grams of them, whole quintals will have to be mined and refined.


2. A few grams of the enriched isotope can deliver energy worth hundreds of tons of coal. At the same time, the undermining consequence is that the design of the power plant has to be such that it can withstand the generation of such amounts of energy in a matter of seconds.


3. A nuclear fusion reaction, which hasn't yet been deployed in the capacity of power generation, is more than one-million times stronger than a corresponding fission reaction, and produces no nuclear waste (theoretically). However, the engagement of such options has been delayed worldwide not by the costs involved but by the technology required to instigate and sustain such reactions.

 

[caption id="attachment_20595" align="aligncenter" width="600" caption="The sun is essentially a nuclear fusion powerhouse."][/caption]

I am not writing to clarify which side of the debate (nuclear v. non-nuclear) I lie on but only to highlight the simple concepts and procedures that sustain any interest on the widespread use of NPPs. Let's begin with the fuel cycle.

 

Every atom (except hydrogen's) contains a nucleus that, in turn, contains protons and neutrons in some number. More often than not, the difference between the number of protons and the number of neutrons is 0 or 1. The protons have a positive charge, are each about 1,800 times times heavier than an electron, and are bound to the neutrons by the strongest natural force: the nuclear force. During a fission reaction, it is the sundering of this bond that yields the gargantuan amounts of energy. The electrons in the atom exist around the nucleus at multiple energy levels, which are called so because all electrons in the same level have the same amount of potential energy.

 

To set off a nuclear reaction, i.e., to break up the nucleus, the trick is to make it heavy and, thus, unstable, like a 10-kilogram dumbbell with a central bar made of straw. To make it heavier, a suitable particle has to be forced into the nucleus. Such force is necessary because of two reasons.

1. The protons and neutrons are both heavy particles. Forcing a much-lighter electron in would have no appreciable effect on the total mass of the nucleus.


2. The protons are positively-charged, which rules out the option of forcing extra protons into the nucleus because of the Coloumbic, or electric, repelling force.

The obvious conclusion is the use of a neutron. However, not all neutrons can be used because it is necessary that the nuclear trap the neutron, become heavier and start disintegrating instead of having the neutron zip past with no useful effect. Such slowed neutrons are called thermal neutrons, and when these thermal neutrons are captured by nuclei, the nuclei become what are called isotopes of their original form.

 

[caption id="attachment_20596" align="aligncenter" width="600" caption="Uranium oxide"][/caption]

Now, in the event of a neutron capture, the chances of fission reactions occurring is not 100%: the nucleus may decide to whine away the excess mass through transmutation processes called alpha- and beta-decays. Having detailed as much, it becomes much easier to understand the working of a nuclear reactor.

1. A reactor core is readied where the nuclear reaction can take place in a controllable environment.


2. Enriched fuel is compacted in the shape of rods and inserted into the reactor core. The more the extent of insertion, the more nuclei are available for a fission reaction.


3. An adjacent chamber is flooded with heavy water and a source of neutrons is placed in it. (The molecular formula for water is H2O, which means each molecule contains two atoms of hydrogen. When these atoms are replaced by an isotope of hydrogen called deuterium, the resulting compound is called deuterium hydroxide or heavy water.)


4. At a suitable position within this arrangement, a provision for control rods is provided. Made of compounds of boron or cadmium, these rods, depending on the extent of their penetration into the chamber, are used to absorb excess neutrons in the event of their proliferation.


5. Voluminous ducts containing a coolant are coiled around the core to remove excess heat. In this case, let's assume the core is water-cooled.


6. When the reactor is ready, the control rods are fully retracted and the neutron source is allowed to generate fast neutrons.


7. These fast neutrons are slowed down upon collision with the surrounding heavy water molecules and become thermal neutrons.


8. The thermal neutrons are fed into the reactor core, where they are absorbed by the nuclei in the fuel rods.


9. A certain proportion of the nuclei begin the fissioning process, releasing massive quantities of kinetic energy, gamma radiation and more neutrons.


10. The kinetic energy manifests as an extremely high temperature within the reactor core.


11. The power plant's pumps are switched on and the water begins to flow in the coiled duct, across which heat is conducted and the water turns to steam. Consequently, the core cools down.


12. The steam is passed through a throttle that converts its pressure energy into kinetic energy, i.e., accelerates the steam into a jet that is guided onto the blades of a turbine that generates power.


13. Meanwhile, in the reactor core, even more neutrons are now available that at the start of the reaction because of the nuclear fission reactions that have already occurred.


14. To keep from all these neutrons causing nuclear havoc, the control rods are inserted enough to keep the rate of reactions tractable.


15. The available neutrons then continue to propagate the fission process with the remaining fuel.


16. The steam, after striking the blades of the turbine, slows down and is collected in a condenser. The vapor is then cooled, compressed and fed once more into the coiled ducts.

This is the nuclear fission process that occurs when a sufficiently enriched isotope is the fuel. Not all isotopes can be used in an NPP for power generation. They must meet certain requirements. For example, U-235 is used because its fission products can be handled to some extent, because the required technology to control its fission reaction exists, and because isotopic uranium is available in nature.

 

Once a neutron has been captured, the U-235 nucleus transmutes to a U-236 nucleus and becomes highly unstable. Because of the excess energy causing the instability, it begins to oscillate and eventually "comes apart", as a result of which the nuclear force breaks down and releases a massive amount of energy. If we assume that the U-235 nucleus was at zero-energy at the beginning and if the incoming thermal neutron had an energy of 1 electron-volt (eV), the resulting explosion releases somewhere around 215 mega-electron-volt (MeV): a jump of 215 million orders. Of this output, 168 MeV is in the form of kinetic energy, 17-26 MeV of gamma rays, 12 MeV of neutrons, 8 MeV of beta particles and the remaining of other fission products.

 

As stated earlier, the chances of a fission reaction occurring are not 100%, and when it doesn't happen, a process called beta decay takes its place. Note the emission of beta particles in a fission reaction: these particle-groups are of two kinds.

1. Negative beta decay: electron + electron anti-neutrino


2. Positive beta decay: positron + electron neutrino

(A positron is the anti-particle of the electron, i.e., it weighs the same as an electron and has all its properties, except for a +1 electrical charge instead of the electron's -1.)

When beta decay is said to occur, only positive or negative beta decay occurs; not both. Now, when a neutrino/anti-neutrino strikes a positively charged nucleus, the collision in question can occur only when a weak force comes into being between the neutrino and the nucleus. This weak force is mediated by a particle called the Z boson, which is an extremely heavy particle. To lose this temporarily gained excess mass/energy, the nucleus beta decays once more to become electrically neutral.

 

[caption id="attachment_20599" align="aligncenter" width="502" caption="Either Ce-173 or Sr-90 placed on a sheet of Alomogordo glass in the presence of a magnetic field emits beta particles, visible as feeble curves on the sheet."][/caption]

The beta decay process is important in reactors that use thorium-232 as nuclear fuel. When a Th-232 nucleus captures a thermal neutron, it undergoes fission, emits some gamma rays, and transmutes to Th-233. Next, Th-233 undergoes negative beta decay to become Pa-233 (protactinium), which beta decays once more to yield U-233. This isotope of uranium then captures a neutron, undergoes fission, releases two more neutrons, and becomes U-232. Now, U-232 is extremely radioactive (it is a strong emitter of gamma rays) and its formation is the principle disadvantage of employing a Th-232 nuclear fission cycle.

 

Therewith concludes the discussion on the principles of a nuclear fission reaction.

Some important calculations and comparisons

For the Tirunelveli district in Tamil Nadu, India, consider the following chart that shows the variation of irradiance against the time of year.

[caption id="attachment_20580" align="aligncenter" width="600" caption="Values courtesy Weather Underground (data from the US National Weather Service)"][/caption]

Considering the energy ratings of the major solar panel-manufacturers in the market, the average efficiency at which they perform (14%), and the average cell temperature on a particular day of the year (34 degrees Celsius), it can be estimated that to produce 169.1875 watts of energy, an initial investment of US $989,688.125 will have to be made against the installation of 1,000 panels, each measuring 1m to a side. Given that there are those who suggest solar energy be used instead of commissioning a nuclear power plant in the district, it should be noted that to make up for the deficit of 2 gigawatts, 11,821,205 panels will have to be installed covering a 11.82 sq. kilometer swath of land at a total cost of US $69,149,911,828.50 or Rs. 3 lakh 39 thousand crore. That is 26 times more than the cost of the two reactors coming up Koodankulam.

The amount of photovoltaic waste generated per one megawatt of peak power, as reported by a study conducted by the German Federal Ministry of the Environment (called the 'Development of the Take Back and Recovery System for Photovoltaic Products', 2007) being 6079.375 tonnes per year (distributed across the planet for the sake of consumption in India), the quantity of waste generated by the year 2020 will be 109,428,750 tonnes. The amount of radioactive nuclear waste generated in the same period in India stands between 3960 tonnes and 5940 tonnes.

Thus, the principle agent owing to which the focus of the media is greater on nuclear energy and lesser on other forms of energy production is radioactivity. If spent nuclear fuel wasn't radioactive, nuclear power plants would make a case for themselves considering they're much cheaper to install, maintain and produce much less waste. That is why it is important to know the processes involved in the manufacture of solar cells and the more-common health hazards posed by those processes: high-efficiency cells contain the mildly-toxic tellurium and indium, and the highly-toxic cadmium and sulfur. Of them, the last three are known to have teratogenic effects.

I'm not trying to build a case against renewable energy resources nor am I trying to build a case for nuclear energy. I'm only making known what the majority do not already see, may not wish to see or simply refuse to see.

Some important calculations and comparisons

For the Tirunelveli district in Tamil Nadu, India, consider the following chart that shows the variation of irradiance against the time of year.

[caption id="attachment_20580" align="aligncenter" width="600" caption="Values courtesy Weather Underground (data from the US National Weather Service)"][/caption]

Considering the energy ratings of the major solar panel-manufacturers in the market, the average efficiency at which they perform (14%), and the average cell temperature on a particular day of the year (34 degrees Celsius), it can be estimated that to produce 169.1875 watts of energy, an initial investment of US $989,688.125 will have to be made against the installation of 1,000 panels, each measuring 1m to a side. Given that there are those who suggest solar energy be used instead of commissioning a nuclear power plant in the district, it should be noted that to make up for the deficit of 2 gigawatts, 11,821,205 panels will have to be installed covering a 11.82 sq. kilometer swath of land at a total cost of US $69,149,911,828.50 or Rs. 3 lakh 39 thousand crore. That is 26 times more than the cost of the two reactors coming up Koodankulam.

The amount of photovoltaic waste generated per one megawatt of peak power, as reported by a study conducted by the German Federal Ministry of the Environment (called the 'Development of the Take Back and Recovery System for Photovoltaic Products', 2007) being 6079.375 tonnes per year (distributed across the planet for the sake of consumption in India), the quantity of waste generated by the year 2020 will be 109,428,750 tonnes. The amount of radioactive nuclear waste generated in the same period in India stands between 3960 tonnes and 5940 tonnes.

Thus, the principle agent owing to which the focus of the media is greater on nuclear energy and lesser on other forms of energy production is radioactivity. If spent nuclear fuel wasn't radioactive, nuclear power plants would make a case for themselves considering they're much cheaper to install, maintain and produce much less waste. That is why it is important to know the processes involved in the manufacture of solar cells and the more-common health hazards posed by those processes: high-efficiency cells contain the mildly-toxic tellurium and indium, and the highly-toxic cadmium and sulfur. Of them, the last three are known to have teratogenic effects.

I'm not trying to build a case against renewable energy resources nor am I trying to build a case for nuclear energy. I'm only making known what the majority do not already see, may not wish to see or simply refuse to see.

The nuclear energy issue

I'm the worst environmentalist around. I can perfectly understand the science of it but, beyond that, I find things to be uncharacteristically slippery. One of the causes I attribute this disorientation to is that environmentalism today has assumed a mostly reactionary nature. I agree that it is completely justified: if we don't work against the ruthless developers today, we won't have greenery to appreciate tomorrow. But I'm not passing judgment, I'm only observing that it has become purely reactionary and that is something I can't tackle very well.

In this context, when some scientist who used to work for the Atomic Energy Commission speaks up that India doesn't really need nuclear power but could make do with solar power, the suggestion itself becomes appropriated as defense against the government's push to establish an NPP in Koodankulam. The principles behind the suggestion, however, are left for the scientists and engineers to deliberate upon. Although the government will consider the advantages and disadvantages of such an installation, the most relevant question is whether such solar farms can withstand the growing energy requirements.

1. Given Tamil Nadu's energy needs and the cost of producing 1 watt of energy from 1 solar cell, the investment will have to be somewhere close to Rs. 17,000 crores (and this excludes all of the costs to follow). However, in order to produce 2 gigawatt of energy in a continuous manner, high-efficiency solar cells will have to be used, with said number hovering somewhere around 40%. This, in turn, places a great stress on the cadmium, mercury and sulfuric acid industries, which are essential components of a solar farm.
2. Given the intermittent nature of solar electricity generation, batteries will have to be integrated with the farming grid in order store energy for later use, and as all engineers are aware, there is a conversion from electrical to chemical energy that occurs with a loss of close to 12%.
3. In each photovoltaic cell, during operation, a photon with a frequency in the visible spectrum of Em radiation knocks out an electron from the valence band to the conduction band, generating a small potential difference that gives rise to a current. The problem is that a single good cell creates only 1.5 volts across its electrodes.
4. Solar cells produce only direct current (DC), which cannot be used for powering appliances before it has been converted to alternating current (AC). Such additions add significantly to the cost of installing a solar farm; at this juncture, being aware of the "money is not a problem" train of thought...
5. Solar electricity is "understood" by policy-makers in terms of its feasibility and grid parity. Feasibility takes into account the amount of solar energy an area receives across the span of one year and, at the given efficiencies, if the solar cells will produce enough energy to achieve parity. Subsequently, grid parity is a determination of whether the cost of electricity generated by other means is less than the cost of electricity generated via solar cells. With twenty-two nuclear power plants in various stages of operation in India, grid parity cannot be hit without installing solar farms that generate tens of gigawatts of energy. Now, return to point #1. 

At the most fundamental level, solar farms can be grid-connected to reduce the load on existing coal-fired and nuclear-powered plants; this essentially means that an installed solar farm can make up for an extant shortage. The principle reason due to which the Indian government is pushing for an NPP is that it wants to define industrial growth rates for the future, and the current status of research and developments on solar cells is insufficient to handle such growth rates. Now, this is purely an indictment of the government's ambitious visions that, more often than not, disregard regional issues, but at the same time, it is definitely something that environmentalists must make a note of before they (or we?) begin to campaign for it.

Such a consideration is important because it characterizes an attitude. The ongoing protest at Koodankulam by its inhabitants is completely justified because it will impact their livelihoods. When a firebrand environmentalist jumps in, however, and calls for solar farms to be installed instead, he is not making a good case for himself; what he should've called for instead is that the government reexamine its development policies. He should've protested against the government's attempts to maintain a "sustainable" growth rate by effecting drastic projects instead of providing alternate solutions that will only continue to sustain such unreasonable expansion. And for as long as reactionary environmentalists campaign against a particular thing, they will not have campaigned for the right reasons.

(What are the right reasons? Against crazy growth rates? How is a crazy growth rate defined when there is no notion of a fixed quota? Where do we draw the line? I'll save that for another day and another post.)

On a final note: why the Indian government insists on installing an NPP along the coast is beyond me. Many of the lessons of Fukushima have been learnt too literally by other countries - the safeguards that were missing there aren't missing everywhere else - but what a natural disaster did was shift the focus away from having a copious source of radiation established along the seashore. At the least, the government could have assuaged opposition from such quarters by planning for the NPP to be installed further inland.

The nuclear energy issue

I'm the worst environmentalist around. I can perfectly understand the science of it but, beyond that, I find things to be uncharacteristically slippery. One of the causes I attribute this disorientation to is that environmentalism today has assumed a mostly reactionary nature. I agree that it is completely justified: if we don't work against the ruthless developers today, we won't have greenery to appreciate tomorrow. But I'm not passing judgment, I'm only observing that it has become purely reactionary and that is something I can't tackle very well.

In this context, when some scientist who used to work for the Atomic Energy Commission speaks up that India doesn't really need nuclear power but could make do with solar power, the suggestion itself becomes appropriated as defense against the government's push to establish an NPP in Koodankulam. The principles behind the suggestion, however, are left for the scientists and engineers to deliberate upon. Although the government will consider the advantages and disadvantages of such an installation, the most relevant question is whether such solar farms can withstand the growing energy requirements.

1. Given Tamil Nadu's energy needs and the cost of producing 1 watt of energy from 1 solar cell, the investment will have to be somewhere close to Rs. 17,000 crores (and this excludes all of the costs to follow). However, in order to produce 2 gigawatt of energy in a continuous manner, high-efficiency solar cells will have to be used, with said number hovering somewhere around 40%. This, in turn, places a great stress on the cadmium, mercury and sulfuric acid industries, which are essential components of a solar farm.
2. Given the intermittent nature of solar electricity generation, batteries will have to be integrated with the farming grid in order store energy for later use, and as all engineers are aware, there is a conversion from electrical to chemical energy that occurs with a loss of close to 12%.
3. In each photovoltaic cell, during operation, a photon with a frequency in the visible spectrum of Em radiation knocks out an electron from the valence band to the conduction band, generating a small potential difference that gives rise to a current. The problem is that a single good cell creates only 1.5 volts across its electrodes.
4. Solar cells produce only direct current (DC), which cannot be used for powering appliances before it has been converted to alternating current (AC). Such additions add significantly to the cost of installing a solar farm; at this juncture, being aware of the "money is not a problem" train of thought...
5. Solar electricity is "understood" by policy-makers in terms of its feasibility and grid parity. Feasibility takes into account the amount of solar energy an area receives across the span of one year and, at the given efficiencies, if the solar cells will produce enough energy to achieve parity. Subsequently, grid parity is a determination of whether the cost of electricity generated by other means is less than the cost of electricity generated via solar cells. With twenty-two nuclear power plants in various stages of operation in India, grid parity cannot be hit without installing solar farms that generate tens of gigawatts of energy. Now, return to point #1. 

At the most fundamental level, solar farms can be grid-connected to reduce the load on existing coal-fired and nuclear-powered plants; this essentially means that an installed solar farm can make up for an extant shortage. The principle reason due to which the Indian government is pushing for an NPP is that it wants to define industrial growth rates for the future, and the current status of research and developments on solar cells is insufficient to handle such growth rates. Now, this is purely an indictment of the government's ambitious visions that, more often than not, disregard regional issues, but at the same time, it is definitely something that environmentalists must make a note of before they (or we?) begin to campaign for it.

Such a consideration is important because it characterizes an attitude. The ongoing protest at Koodankulam by its inhabitants is completely justified because it will impact their livelihoods. When a firebrand environmentalist jumps in, however, and calls for solar farms to be installed instead, he is not making a good case for himself; what he should've called for instead is that the government reexamine its development policies. He should've protested against the government's attempts to maintain a "sustainable" growth rate by effecting drastic projects instead of providing alternate solutions that will only continue to sustain such unreasonable expansion. And for as long as reactionary environmentalists campaign against a particular thing, they will not have campaigned for the right reasons.

(What are the right reasons? Against crazy growth rates? How is a crazy growth rate defined when there is no notion of a fixed quota? Where do we draw the line? I'll save that for another day and another post.)

On a final note: why the Indian government insists on installing an NPP along the coast is beyond me. Many of the lessons of Fukushima have been learnt too literally by other countries - the safeguards that were missing there aren't missing everywhere else - but what a natural disaster did was shift the focus away from having a copious source of radiation established along the seashore. At the least, the government could have assuaged opposition from such quarters by planning for the NPP to be installed further inland.