Power reactors discharge a small amount of radioactive material into the environment under normal operating conditions. See figures 4.1 through 4.12 in the report. The Palo Verde Nuclear Generating Station in Arizona [0] released 1844 curies of radionuclides in a year from gaseous, liquid, and particulate discharges. In SI units, that's 6.8 * 10^13 becquerels.
According to the World Nuclear Association, a kilogram of coal ash contains about 2000 becquerels of radioactive material [1]. In 2012, the United States coal fleet generated about 110 million tons of coal ash [2]. In 2012, the United States generated 1514 terawatt hours of electricity from coal [3]. That puts the coal ash radioactive burden to the environment at roughly 1.45 * 10^11 becquerels per TWh of electricity generated in coal plants.
The Palo Verde annual radioactive effluent discharge of 6.8 * 10^13 becquerels from an average of 32.3 TWh electricity generation [0] comes to 21 * 10^ 11 becquerels per TWh of electricity. Its radioactive discharge to the environment is significantly higher than the average discharged via coal ash to produce an equivalent amount of electricity.
However, before getting alarmed, see figure 2.1 in the NRC Radioactive Effluents report that I linked at the beginning of this post. Even though nuclear plant effluent adds more radiation to the environment than coal ash does, industrial sources of radiation (including nuclear plants) account for about 0.1% of general population radiation exposure. Natural background sources add up to about 50%. So the marginal danger of radioactive exposure from normally operating nuclear plants or coal ash dumps is very small.
People who say that coal plants emit more radiation than nuclear plants are not helping to counter "radiophobia." They are in fact attempting to exploit "radiophobia" to stir up fear over a very minor aspect of coal's environmental harms. (And coal really is an environmental disaster in many other ways.) Worse, people making this argument are not even correct about the underlying numbers. Many of them are just parroting a Scientific American article [4] which itself is a misleadingly garbled retelling of an actual research report [5] [6].
[6] Detailed examination of what the authors were actually reporting in "Radiological Impact of Airborne Effluents of Coal and Nuclear Plants" via my past comment here: https://news.ycombinator.com/item?id=14466887
Nuclear power plants produce many many orders of magnitude more radioactivity than coal power plants for a given amount of energy produced. You are probably misinterpreting the famous 1978 study [1] where the radioactive emissions of nuclear and coal power plants were estimated to be roughly the same. This does not include the solid and liquid nuclear waste, only the radioactive gases that are inadvertently leaked from nuclear reactors. Coal ash is barely radioactive at all, and the radioactivity is completely negligible compared to the chemical toxicity.
Coal generates appreciable amounts of radioactive waste as well:
In fact, the fly ash emitted by a power plant—a by-product from burning coal for electricity—carries into the surrounding environment 100 times more radiation than a nuclear power plant producing the same amount of energy... (As a general clarification, ounce for ounce, coal ash released from a power plant delivers more radiation than nuclear waste shielded via water or dry cask storage.)
I'm not a huge proponent of nuclear power generation—I'd much rather we focus on renewables (especially solar) and storage technology—but if we're going to have radioactive pollution from power generation, I'd much rather it also be carbon neutral. That's ignoring coal's many other environmental deficiencies (mountaintop removal comes immediately to mind).
The point of the 1978 report was that radioactive elements from coal are more likely to be concentrated in the food supply and retained in the body than radioactive elements released from power reactors. That leads to an effective higher radiation dose to people under their modeling assumptions. But nuclear reactors release more becquerels (or curies, to use the older unit) of radioactive material to the environment.
You can see this difference if you look at the original publication via sci-hub.
Table 2 shows an estimated airborne release of about 1.2 curies per year of radionuclides from a 1000 MWe coal plant.
Table 3 shows shows an estimated airborne release in excess of 5000 curies per year of radionuclides from a 1000 MWe nuclear reactor.
But since the reactor radionuclides do not biologically concentrate in food or bones, they are dispersed throughout the environment and human exposure is small.
In table 5 you can see that the whole body population dose commitments for the different sources, in man-rem/year, are 18-23 for coal (depending on stack height) and 13 for a nuclear reactor. So coal is worse but far from 50x worse. Looking exclusively at bone exposure, coal can be an order of magnitude worse since radium released from coal behaves chemically like calcium and concentrates in bones.
Also, because of the natural uranium and thorium in coal, "the fly ash emitted by a power plant — a by-product from burning coal for electricity — carries into the surrounding environment 100 times more radiation than a nuclear power plant producing the same amount of energy." and "As a general clarification, ounce for ounce, coal ash released from a power plant delivers more radiation than nuclear waste shielded via water or dry cask storage.", both quotes from https://www.scientificamerican.com/article/coal-ash-is-more-... .
«According to estimates by the US Oak Ridge National Laboratory, the world’s coal-fired power stations currently generate waste containing around 5,000 tonnes of uranium and 15,000 tonnes of thorium. Collectively, that’s over 100 times more radiation dumped into the environment than that released by nuclear power stations.»
About 1% of it is leaked into air, so about 500 tonnes of uranium and 1500 tonnes of thorium are leaked into air every year.
However, uranium and thorium are much less dangerous than radioactive iodine, strontium, and cesium.
Do we have data/studies on the health effect comparison of the radioactive portion of emitted coal ash and the typical emitted/discharged effluents of a nuclear power plant?
Eg. isn't the NPP discharge much more localized so it affects a lot less people? Or both kinds have some of this and some of that and the gases are carried well with the wind anyway?
Coal power stations produce around 5-10 tonnes of radioactive waste every year. This seems to be ignored for the most part when discussing nuclear energy.
Naturally occurring radioactivity in coal ash means that coal burning power plants release far more radioactivity into our environment than nuclear plants do. In fact, if you want to get the least amount of radioactivity into your body, the safest place is behind the shielding of a nuke plant, because it would also protect you from naturally occuring radiation.
If you add up the total of radioactive elements in Bequerels released annually by coal plants and then assume 100% of all waste from power generating plants could be ground up and released and count that up, the amount of radioactivity from nuclear plants would still be less than coal.
We burn a LOT of coal, and despite the media's portrayal of how much a problem radioactive waste is, it's very overblown for power generating plants. Weapons production is another matter, but we've already been trying to stop that from happening for years.
What is even more interesting: At a given power rating, coal plants produce up to 3 times more radioactivity than nuclear power plants directly in leftover ash because coal contains large numbers of radioactive isotopes. It might not seem like much, but when you consider that a 1TWe coal plant burns 3.2Mt of coal a year compared to 27t of uranium for an equivalent nuclear power plant, this might become more apparent.
Most of that waste is captured in ash via particle filters and has to be treated like any highly toxic and radioactive waste, but as far as I know this waste it not destined for secured long term nuclear disposal where it would be kept safe from interacting with the environment. We don’t seem to have a problem with that…
Further, some low percentage (literature tends to point at .5%) of it is in gaseous form or cannot be filtered, so it gets vented into the atmosphere. That’s assuming modern and intact particle filters. And we aren’t even talking about CO2 here.
It’s somewhat absurd we have to have discussions about nuclear power plant waste in this reality.
> In fact, the fly ash emitted by a power plant—a by-product from burning coal for electricity—carries into the surrounding environment 100 times more radiation than a nuclear power plant producing the same amount of energy.
> In a 1978 paper for Science, J. P. McBride at Oak Ridge National Laboratory (ORNL) and his colleagues looked at the uranium and thorium content of fly ash from coal-fired power plants in Tennessee and Alabama. To answer the question of just how harmful leaching could be, the scientists estimated radiation exposure around the coal plants and compared it with exposure levels around boiling-water reactor and pressurized-water nuclear power plants.
> The result: estimated radiation doses ingested by people living near the coal plants were equal to or higher than doses for people living around the nuclear facilities. At one extreme, the scientists estimated fly ash radiation in individuals' bones at around 18 millirems (thousandths of a rem, a unit for measuring doses of ionizing radiation) a year. Doses for the two nuclear plants, by contrast, ranged from between three and six millirems for the same period. And when all food was grown in the area, radiation doses were 50 to 200 percent higher around the coal plants.
Coal power plants release a LOT of radioactive material into the atmosphere, much more than the couple of barrels of nicely storable waste a nuclear plant produces.
Coal ash tends to have a high volume of Carbon-14 which, in the volumes used to burn coal for electricity, releases significantly more radioactivity than any normally operating nuclear plant. Even just a large pile of unburnt coal is much more radioactive than your average pile of rocks
https://www.nrc.gov/docs/ML1036/ML103620452.pdf
Power reactors discharge a small amount of radioactive material into the environment under normal operating conditions. See figures 4.1 through 4.12 in the report. The Palo Verde Nuclear Generating Station in Arizona [0] released 1844 curies of radionuclides in a year from gaseous, liquid, and particulate discharges. In SI units, that's 6.8 * 10^13 becquerels.
According to the World Nuclear Association, a kilogram of coal ash contains about 2000 becquerels of radioactive material [1]. In 2012, the United States coal fleet generated about 110 million tons of coal ash [2]. In 2012, the United States generated 1514 terawatt hours of electricity from coal [3]. That puts the coal ash radioactive burden to the environment at roughly 1.45 * 10^11 becquerels per TWh of electricity generated in coal plants.
The Palo Verde annual radioactive effluent discharge of 6.8 * 10^13 becquerels from an average of 32.3 TWh electricity generation [0] comes to 21 * 10^ 11 becquerels per TWh of electricity. Its radioactive discharge to the environment is significantly higher than the average discharged via coal ash to produce an equivalent amount of electricity.
However, before getting alarmed, see figure 2.1 in the NRC Radioactive Effluents report that I linked at the beginning of this post. Even though nuclear plant effluent adds more radiation to the environment than coal ash does, industrial sources of radiation (including nuclear plants) account for about 0.1% of general population radiation exposure. Natural background sources add up to about 50%. So the marginal danger of radioactive exposure from normally operating nuclear plants or coal ash dumps is very small.
People who say that coal plants emit more radiation than nuclear plants are not helping to counter "radiophobia." They are in fact attempting to exploit "radiophobia" to stir up fear over a very minor aspect of coal's environmental harms. (And coal really is an environmental disaster in many other ways.) Worse, people making this argument are not even correct about the underlying numbers. Many of them are just parroting a Scientific American article [4] which itself is a misleadingly garbled retelling of an actual research report [5] [6].
[0] https://en.wikipedia.org/wiki/Palo_Verde_Nuclear_Generating_...
[1] http://www.world-nuclear.org/uploadedFiles/org/Features/Radi...
[2] https://www.epa.gov/coalash
[3] https://en.wikipedia.org/wiki/Energy_in_the_United_States#El...
[4] "Coal Ash Is More Radioactive Than Nuclear Waste" https://www.scientificamerican.com/article/coal-ash-is-more-...
[5] "Radiological Impact of Airborne Effluents of Coal and Nuclear Plants" https://science.sciencemag.org/content/202/4372/1045
[6] Detailed examination of what the authors were actually reporting in "Radiological Impact of Airborne Effluents of Coal and Nuclear Plants" via my past comment here: https://news.ycombinator.com/item?id=14466887
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