ASME E-Fest

Debunking Nuclear Myths..




Myth #1

Most of the Harmful Radiation exposure comes from Nuclear power plants

Let's talk numbers;
If you are residing within 50 mile radius of a Nuclear fission power plant, you would receive an average annual radiation dose of 0.01millirem / 0.0001 millisievert. Putting this in comparison to natural background radiation, the average person in U.S is exposed to about 300 millirems/ 0.03 mSv in a year. 
The Worldwide average of effective dose from background natural radiation is close to 2.4 mSv/year. In Kerala coast this  tends to 12.5 mSv/year. In northern Iran, this value is close to 260 mSv/year. 
(A millisievert or mSv is a unit of radiation dose that can be used to estimate cancer risk.)

Fact to be mentioned : "Coal ash is much more radioactive than Nuclear waste"

 "Coal ash add 100 times more radiation to the environment than a nuclear power plant generating the same power output". 

By burning this pesky 'black diamonds', coal power plants produce lots of radiation. Naturally coal contains both Uranium and thorium. When burned the concentration of these radioactive elements get up to 10 times their original levels. Fly ash uranium sometimes leach into the grounds near coal power plant and affect farmlands and water bodies. Radiation level in people living near coal power plant was found to be 18 millirems, in contrast from two nuclear plants the dosed ranged from 3 to 6 millirems for the same period. But the chance of getting adverse health effects by both coal and nuclear plants are meagre. 

"If it's one in billion chance in case of Nuclear power plant, it's one in 10 million to one in a 100 million for coal plants." 




It will be hard to believe but, 
flying in an airplane exposes us to more radiation than by just standing near a nuclear reactor
The radiation dose received by a traveler in a typical commercial airliner (35000 ft) is about 0.003 millisieverts/hour. As at high altitudes the atmosphere is thinner, so less molecules of air are available for deflecting cosmic rays from the space. So, the higher you fly the more radiation you are going to get exposed to. 

We are exposed to radiations from various sources in or daily lives, from the sun from the mines and many more. We get most of the radiation exposures from Radon (The real don). It can easily move through air, ground and water bodies. Radon is ubiquitous element found in rock and soil. Burning fossil fuels releases Radon. It can also be found in certain spring-waters and hot springs. Basically, we are living surrounded by radiations more in dose than what we get from Nuclear power plants. Number of radon gas induced lung cancer is only second to cigarette smoking in U.S.  

A chest x-ray, for instance, delivers 0.1 mSv, while a chest CT-scan delivers 7 mSv — 70 times as much. And that's not counting the very common follow-up CT scans. Just compare this to above mentioned exposure from Nuclear power plants. 

The most widely celebrated model postulates that the cause of cancers due to ionizing radiations increases linearly with effective radiation dose at a rate of 5.5% per sievert. If this linear model is accurate, then natural background radiation is the most hazardous source of radiation to public health, followed by medical imaging as a close second.  

Wait a minute, did you find the word nuclear in the above statement?
 
File:Radiation warning symbol.svg - Wikimedia Commons

We need more of these signs around Coal power plants than Nuclear power plants.

Most of the Harmful Radiation exposure comes from Nuclear power plants  #MythBusted


Myth #2

Nuclear Waste is way too much for safe disposal and is dangerous for the environment

The amount of waste produced by any nuclear plant is way too less as compared to those produced by the thermal power plants, coal, oil and gas. Most nuclear waste produced is hazardous, due to its radioactivity, only for a few tens of years and is disposed of in safe disposal facilities. Only a small volume fraction of nuclear waste (about 3% of the total vol.) is long-lived and highly radioactive and requires isolation for many thousands of years. Most of the nuclear facilities around the world just dumped their nuclear waste put into those yellow canisters at the plant site only and are quite safe. Nuclear waste are the only kind of waste which is safely stored away other wastes are generally released to the environment as gas or other toxic materials.

Talking about coal, driven by higher energy demand in 2018, global power plant carbon emissions rose 1.7% to a historic high of 33.1 Gt carbon dioxide. Emission from Coal power plants alone contributed to about 10 Gt Carbon dioxide, mostly in Asia. China, India, and the United States accounted for 85% of the net increase in emissions, while emissions declined for Germany, Japan, Mexico, France and the United Kingdom.
(Gt-Gigaton)
At the safer end there is Nuclear with apparently zero-carbon emission. So, nuclear in terms of carbon footprint is the cleanest source for energy production. The energy density of the fuel used provides insight into its environmental and health impacts. The nuclear fuel is very dense, hence a small pellet of Uranium can produce lots of energy as compared to coal and other sources which requires tons of fuel for the same amount of power. In turn  more waste is produced.  

Energy release:- 1 Uranium pellet = 10 gallons of oil = 1 ton of coal

And as of solid waste the coal ash from thermal power plant which are just openly dumped in landfills can deliver more radiation and can have other adverse effects such as soil pollution. The fly ash if left unchecked can cause respiratory diseases.+

If reprocessing is used to separate the unused uranium from
the spent nuclear fuel, then the amount of highly radioactive waste
remaining from the 1000-MW(e) nuclear plant amounts to substantially less than 10 tons per year. In contrast, 5% or more of the coal
burned becomes ash that must be removed and stored in a landfill or
elsewhere at the rate of more than five 100-ton-capacity railroad cars
per day. Likewise it may be necessary to prevent nearly 100 tons of
sulfur dioxide and lesser amounts of mercury, lead, and other impurities from being released to the environment. But the largest environmental impact from burning fossil fuels may well be the global
warming caused by the thousands of tons of CO2 released to the
atmosphere each day by a 1000-MW(e) coal-fired power plant.

Even more waste is generated from solar panel disposal which can have direct impact on environment and animals by releasing toxic substances like lead, cadmium, and chromium. 



All of the high level spent nuclear fuel produced by the nuclear energy industry in U.S over the past 60 years could fit on a football field at a depth of less than 10 yards!!
That's quite a small space occupied by the nuclear waste as compared to wastes such as carbon dioxide which are released to the atmosphere in amounts of Gigatons per year .

That is about 5,280 sq. meters of land. Vatican City, the smallest of the countries around the world has an land area of about 517997 sq meters. So, by this comparison if we have a land area same as the Vatican city  for safe disposal of nuclear waste, it can store spent fuel  that will be produced by the nuclear industries over 6000 years of their operation. Above argument is not quite accurate because as population increases we will need more nuclear plants hence more waste will be produced, in turn more land will be required. But being able to store even 500 years of waste in such a tiny space (in contrast with the total human inhabitable area on earth), is like an ant or even smaller in front of African elephant, in comparison to the area taken for disposal of coal ash and other wastes generated by fossil fuel and even renewables. 

 Greenpeace, an environmental group estimates that there is a global stockpile of about 250,000 tons of toxic spent fuel spread across 14 countries, based on data from the IAEA.
Out of that, 22,000 cubic meters—roughly equivalent to a three-meter high building covering an area the size of a soccer ground—is hazardous, according to the IAEA.

Apart from deep-long storage other innovative methods have been engineered in the past years that can reprocess the spent fuel for reusing it in nuclear reactors, particularly known as breeder reactors. Some advanced reactors designs being developed around the world could operate on used fuel. Thorium as fuel in breeder reactors has been proposed for commercial use, the spent fuel from which is less radioactive as compared to U-238 from fission of U-235.

The nuclear industry has developed and implemented most of the  technologies essential for the final disposal of  the waste it generates. The remaining issue is one of public acceptance, and not of technological feasibility. A fast decaying element is much more harmful than a long half-life decaying element like plutonium (a nuclear waste).

Nuclear Waste is way too much for safe disposal and is dangerous for the environment  #MythBusted


Myth #3

A Nuclear Power plant can blow up like an atom bomb 



A nuclear reactor can never blow up like an atom bomb. In conventional nuclear reactors there are chances of catastrophic meltdown due to failure in coolant system. This can occur due to fault in operational system like in Chernobyl Nuclear power plant or due to natural disaster like in Fukushima. But direct fatalities from such past events were less and modern nuclear reactors promise no meltdown during operation of power plants and also have systems to tackle problem caused by natural disasters. It will be unfair if we are going to compare the safety of nuclear based on these 2-3 events in the entire history to the millions death caused by air pollution annually from thermal power plants. Chernobyl is just a tiny land mass affected by that event but carbon dioxide affects the entire globe.

Blowing up of a nuclear power plant like an atom bomb is not possible. Because the fuel used in the reactor are not enriched to such a level to make a bomb out of it. Different nations have regulations imposed on the enrichment of Uranium used in nuclear plant to such levels where it can not be used for nuclear proliferation. Weapons grade U-235 needs to be enriched upto 90% (>85%) for usage in nuclear weapons. Where as reactor grade Uranium-235 enrichment ranges from 3-5 % generally (basically <20%). Nuclear reactors also control the criticality of the nuclear reaction by using neutron absorbing materials/control rod.  

The design of any nuclear reactor is such that it is constantly cooled by a coolant extracting the heat generated at the core. Various safety systems are being employed into existing nuclear power plants to avoid meltdown events due to natural disasters. Modern nuclear plants are build underground to avoid airborne attacks or airplane crashes. Nowadays, the reactor is placed behind several safety walls and is placed underground to avoid leakage of radiation due meltdown. Seismic Isolators are being used for safety during earthquake. The IAEA attempts to monitor and control enriched uranium supplies and processes in its efforts to ensure nuclear power generation safety and check nuclear weapons proliferation. 




A Nuclear Power plant can blow up like an atom bomb  #MythBusted

The question burns down to, are we going to turn our only planet into a frying pan by being ignorant of a clean source and safe like Nuclear just by fictitious fears of getting mutated into a zombie ? (LOL)
Or are we going to live through a stigmatized civilization having no faith in our technologies?



Citations for the above article...

















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