Risk and Return Period

Risk of (partial) unpredictable natural and industrial accident are usually assessed by attempting to calculate the Return Period for this event.
A similar concept is Mean Time Between Failures (MTBF), which apparently is more relevant when assessing breakdown due to the wear of industrial equipment.
A more thorough assessment can probably be obtained by using Probabilistic Risk Assessment.

Slightly simplified, we can say that if you sit at a river and wait for a flood (of this river at this point) then the average waiting time between this – or more serious – flooding is a measure for the return period.

A few extreme examples

Flooding in Mozambique

Some time ago a tornado hit an area in Mozambique.
All infrastructure in the affected area along with an unknown number of people were swept out to the ocean.
But this incident was so special that the return period was estimated to be several thousand years.
This was included in the planning of the reconstruction.

The extreme

Without connection to this, I was asked to evaluate a building’s collapse, allegedly due to an extraordinary wind.
My estimate was that the age of the universe was a blink in the eye in comparison with the return period for the alleged combination of events.
The insurance paid as an “Act Of Good”.

Morning Call from the Mosque

If you are unfortunate enough to live next to a mosque you will be called to prayer five o’clock in the morning.
Here is the Return Period in return only 24 hours.

The subject of the following

In the following I will try to assess and counter some of the misconceptions that come up in the debate about damage from the windturbines and from the nuclear power, we will get, even in Denmark – sooner or later.

Windturbines – Return Period for noise

If you are plagued by noise from a wind turbine, the return period will be about one week.

Nuclear – Return Period of accidents

First, I emphasize that a realistic discussion on the safety of future European systems for nuclear, will naturally exclude the irresponsible amd dangerous type of reactor at Chernobyl.
Similarly, I also consider the accident at Fukushima, as being irrelevant to the assessment of future European nuclear power.
——- If you, my unknown reader, want to include these accidents in your
——- assessment, I pray you read the two links above.
The reactors, that will be relevant in this discussion, have together been in use over 15,000 “reactor -years”.
There have only been one serious accident and no injuries.

The damage

Typical of the vexatious discussion, we are often meet with the mention of the risk of a near-fictional disaster which then will have a great psychological effect.
A logical assessment of risk and damage will roughly be based on the calculation of sum of risk times damage.
The mathematical treatment can obviously be refined, but it is not honest to deviate from this principle.

Windmills – Damage

The lobbying for windturbines has done a great job to influence the public to disregard what I think is well-documented damage from noise and flash of light from wind turbines.

To add a little realities, I will mention that 30% of neighbors of wind turbines are bothered “a lot” or “somehow”.
Source: Energy Spply that certainly are not against wind power.
At another page I have tried to assess the facts.

Nuclear power – Damage

The only serious accident that is relevant in this discussion was about Three Mile Island.
There was paid compensation ($ 40 million) for loss of earnings due to enforced but unnecessary evacuations.
There was major economic damage but no injuries.

The subject of the following

In the following I will try to assess and counter some of the misconceptions that come up in the debate about damage from the wind and from the nuclear power, we will have, also in Denmark – sooner or later.

Windmills – Return Period for noise

If you are plagued by noise from a wind turbine, the return period will be about one week.

Nuclear – Return Period of accidents

First, I emphasize that a useful discussion on the safety of future European systems for nuclear naturally exclude the irresponsible and dangerous type of reactor at Chernobyl.
Similarly, I also consider the accident at Fukushima, as being irrelevant to the assessment of future European nuclear power.
——- If you, my unknown reader, want to include these accidents in your — —- assessment, I pray you read the two link above.
The reactors that will be relevant in this discussion, have together been in use over 15,000 “reactor-year “.
There has only been one serious accident and no injuries.

Windmills – Damage

The energetic lobbying has done a great job to influence the public to disregard what I think is well-documented damage from noise and flash of light from wind turbines.

To add a little realities, I will mention that 30% of neighbors of wind turbines are bothered “very much” or “somehow”.
Source: Energy Spply that certainly are not against wind power.
At another side I have tried to elaborate on the facts.

Nuclear power – Damage

The only serious accident that is relevant in this discussion was at
Three Mile Island.
There was paid compensation ($ 40 million) for loss of earnings due to enforced but unnecessary evacuations.
There were major economic damage but no injuries.

Usually you assess the risk of core damage (core meltdown).
For the much talked about EPR it is is set to 4 x 10 -7 per plant per year. (Or a return period of two million years.)
For the nearest competitor APR-1400, having significantly lower cost, return period is (only) one hundred thousand years.

Such a core damage would be an economic disaster.
But as all relevant reactors are provided with a reactor containment, the risk of injury associated with such a core meltdown is very small.
This is seen by assessing the difference between accidents at
Tree Mile Island and at Chernobyl.

To proceed, I must emphasize that the reactors as we know them today have a much better safety than at Three Mile Island.
And that the reactors, that sooner or later will be built – even in Denmark – will have an even greater security.
Yet:
As already mentioned, the Return Period for the reactors that were built been a long time, be well over 15,000 years.
—— Of course, it is possible to fantasize to a reactor accident
—- – with major release of radioactive material.
—— However, the one who looks at the realities regard this as I, little —- —— churlish, call a typical Greenpeace hoax.
AND
—— It is understood that about 5,000 meteors of football-size
—— hit the earth each year.

—— Of course it can not be excluded that such a meteor falls,
—- – exactly on a nuclear reactor.

But even a terrorist with a Jumbojet will not open up for radioactive materials – only fear and damage.

Conclusion

When assessing the building of, for example, a dam we asses as income the value of electricity produced and / or value of future irrigation.
Actually also the value of the savings achieved by avoiding future flooding.
Expenditure will include the damage caused by a collapse divided by risk (return period) of this collapse.
Both will be measured in €/year.

Similarly, damage from potential sources of energy should be weighed against the value of the
pollution-free electricity that will be produced.

With the above-mentioned reactor and a return period of 15,000 years refearing to this only one relevant accident, it is relatively easy to make a meaningful analysis of nuclear power safety:
—— Very large economic damage divided with a return-period of
– —- over 15,000 years.

Newer reactors, such as those now being built, will have a significantly better safety.

Globally, there are thousands of people who are bothered by noise from wind turbines.
Return period for these genes is probably less than ten days
Here it is reasonable to assess the following:
—— Number of people affected times the damage per person divided by —- – return-period.
—— (Also € / year)

I am not able to price the human suffering and ask any readers help to make the necessary calculations when it comes to wind turbines.

“Renewable” Energy

Too often we see that cheating on the weight in such a way that the contribution of solar and wind calculated over a longer period.
However, electricity is the most perishable commodity that exists.
Unfortunately, one must therefore conclude that renewable energy does not fit for the requirements of the modern world.

Pollution

The above can best be understood as the assessment of nuclear power versus wind.
When assessing the differences between power from coal and oil to renewable energy (wind, solar, nuclear) should try to take account of pollution.
Here I will only mention the following:
– Over 2000 people die annually from accidents in coal mines.
– Over two million die because of air pollution from burning coal.
– A looming climate catastrophe.

For the one who is worried both for people’s health, the climate and mankind access to reliable energy, maybe this is the real question.


Black Swan Theory

black swan Extreme and “unpredictable” accidents has been treated at this link.
It dominates in this assessment is the financial crash and the like.
Worst possible man-made disaster will probably be associated with a dam failure.
Of course there are international experts who assess nuclear safety.
BUT
In the context of Nuclear the actual Black Swan risk is associated with politically motivated measures.
Such as when, in Germany without notice and without adequate compensation “such just” decided to phase out nuclear power.

A needed comparison

Of course, people have tried to compare the damage from a disaster at a nuclear power plant with other injuries.
The closest I have come is the following:
—— “If you count the pollution would be a disaster, as at
—— Chernobyl, every ten years is to preferable compared to
—— the current. “

AND
—— “We can only look at the statistics. We have had nuclear power
—— since 1954, but in the western world, we have only experienced
—— one meltdown on the Three Mile Island in the United States.
—— It was the worst we have experienced, and no one was harmed. “

For the record, I repeat that talking about a future Chernobyl accident is outside all realistic assessment.
A core meltdown as at Three Mile Island is a possibility and, as mentioned, it will have a Return Period of over 15,000 years.
New reactors that are realistic for the expansion of nuclear power, will have a Return Period, some ten times as much.
Thus, with the future expansion of nuclear power, it will take far more than 50 years between any similar accidents, as already mentioned, are unlikely to cause damage to humans.

Final notes

In an attempt to botch the discussion, it has been argued that if there are 1000 nuclear power plants would return period for a serious accident not be 15,000 years but 15 years.
If you go for this, it must be counted to the expected benefits will be correspondingly increased. Thus the outcome of considerations will not change.
Furthermore, I would emphasize that an accident in South America not to have effects in Europe. – In addition to the psychological.

CO2-free energi.png But why is the general assessment of risk a lack of logic?
Maybe some of the answer is found here.

Greetings and good reflection
Thorkil Søe

If you have the strength and will see my attempt to assess the troublesome reality.
So see another entry:
(Unnecessary) Safety of Nuclear

Advertisements