Archive for Chernobyl

Fukushima – A Disaster Waiting In The Wings?

Posted in Environment, Modern World, Nuclear, Oceans, Radioactive Waste, Toxic Waste with tags , , , , , , , on 13/04/2011 by floroy1942

Should we be concerned at the latest news of a hike in the severity level at the Fukushima nuclear generating plant to 7, bringing it on a par with Chernobyl?

Chernobyl Reactor Building

We can all remember what happened at the Russian plant, but the experts tell us there is no danger of a repeat. Now that is reassuring news, certainly to the Japanese, and probably for the rest of us too.

The whole episode however leaves me with some questions, most important of which is, why was a nuclear plant built on the coast in an earthquake/tsunami zone? Reactor One was opened in July 1967, and since then another five have been built on the same site.

http://www.youtube.com/embed/Noqk78bjE-Q

The Cause Of A Tsunami

It is safe to assume that we did not know as much in 1967 as we do now about earthquakes and the effects, but even so, it seems to me the Japanese were taking a big chance in building such a facility right on the sea shore.

I can well imagine their desire to have a ready supply of water for cooling the reactor, but then surely, better precautions should have been taken to protect the installation against the possibility of a tsunami.

The Tsunami Strikes

History has shown us on many occasions that earthquakes under the sea cause tsunami’s, so it should be obvious, even in 1967, that the site would be prone to just such an event.

I freely admit, I am no nuclear scientist or structural engineer, but it seems to me that building such a plant on the coast at Fukushima, knowing the possibilities, should have received more attention.

The main difference between Chernobyl and Fukushima is that in the former accident the reactor vessel ruptured, releasing large amounts of radioactivity into the atmosphere, whereas in the latter, this did not happen and the reactor vessel remained intact. Contrary to popular opinion, there is never a chance of a nuclear explosion at a nuclear power plant, even if meltdown does occur.

http://www.youtube.com/embed/Z69rtx3YlE0

Fukushima Reactor

Each reactor at the Fukushima plant has a secondary containment vessel which is designed to prevent the release of radioactive particles into the atmosphere even in the event of a reactor containment vessel breach. This was not the case at Chernobyl and indeed, very few Russian plants had such a safety facility (lessons learned).

Furthermore, The Chernobyl reactor was ‘fired up’ at the time of the accident while experiments were carried out on the power generators for the emergency cooling system. At Fukushima the reactor shut-down automatically when the earthquake was detected.

Typical Reactor Cooling System Generator

It would seem that the problems began at Fukushima when the various backup cooling pumps, that supply the core with water to keep it from overheating, lost power when the tsunami destroyed the generators supplying the pumps. It would appear that perhaps more protection should have been given to these vital components.

Fukushima Damage

The disaster at Fukushima, though of natural causes, does indicate that more attention must be given to the siting of nuclear power plants, especially in earthquake prone countries around the famous ‘Ring of Fire’ bordering the Pacific. It indicates that all nuclear plants should be inspected to see what improvements can be made to the operating systems when a natural disaster strikes, and most specifcally, protection of the cooling apparatus.

Anyone wishing for a simple straight-forward explanation of the events at Fukushima should visit the following site:

http://bravenewclimate.com/2011/03/13/fukushima-simple-explanation/

Its all well and good for armchair ‘experts’ to give their opinions, and as we all know hindsight is a wonderful thing, but I should hope that some valuable lessons have been learned from this disaster and steps are taken to see such an event is never repeated.

Fukushima Heros

In the meantime, we should not forget the brave men and women who have been working tirelessly to prevent a major disaster at Fukushima at the risk of their own well-being. I salute you!

One thing is sure, we are a long way from doing away with our nuclear power plants despite all the hype that has been generated, for until the scientists come up with something better we are stuck with it. At this moment in time we have no other way of keeping up with the ever increasing demands for power.

Roy. 

Germany – The Nuclear Dilemma

Posted in Britain, Demonstration, England, Environment, Europe, Germany, Government, Modern World, Nuclear, Radioactive Waste, UK, USA with tags , , , , , , , , , , , on 09/11/2010 by floroy1942

Germany hit the news this past week due to the demonstrations against nuclear power in the country, but what of the core question: Can we do without nuclear power?

The Gorlagen Express

It all centred around a train-load of nuclear waste being transported to the storage depot at Gorleben after treatment in France. Gorleben is the site of old salt mines that have been used for radioactive waste storage for the last three decades.

Throughout these thirty years, each successive train-load has met with demonstrations by anti-nuclear activists, but this year the demonstrations had a higher significance. The increased anger felt by the protesters was centred on the German governments recent decision to extend the life of the countries 17 nuclear power stations by a further 12 years to 2032, a reversal of a year 2000 decision to phase out all nuclear facilities.

Chernobyl - Nightmare Scenario

The German people have always been against nuclear power since the first experimental atomic power station was opened in Kahl-am-Main in 1960. Already nervous at the idea, this fear was heightened by the Three-Mile Island (Pennsylvania) incident in 1970, and more significantly, the Chernobyl disaster in 1986 which covered Germany in radioactive dust and required a massive clean-up operation.

Since the introduction of nuclear power to the world there have been accidents in many countries in which small amounts of radioactivity have escaped, all were due to human error and no-one in their right minds will ever be convinced that it is a 100% safe method of generating electricity. But there again, what is 100%  safe these days? I’ll tell you – Nothing!

The problem lies in the fact that we have become ‘power’ hungry, and since we entered the digital age the electricity requirements have jumped ten-fold in the industrialised nations. Coupled with this is the lack of a viable alternate method of supplying our energy needs. Our hunger for more power has become so great that to satisfy it with wind, sun, biofuels or hydro-electric power is utterly impossible, despite what their supporters say.

Another sticking point is the ever-increasing demands from developing counties such as India, China and the like as they take their first steps to becoming great industrialised nations.

It would appear that at present, no-one has a foolproof second option. If demonstrators were asked for an alternative, most would probably reply “wind”. There are already wind turbine ‘farms’ dotting the landscape in Europe and other countries, but the technology is afflicted by many problems.

Turbine Blade Convoy in UK

First and foremost is their size, which makes them expensive to produce and maintain, and they require specialists with special equipment to erect. They also have to be erected far away from cities and towns, therefore the construction of power lines to get the output where it is needed is costly.

Turbines have a limited life and need constant maintenance because they suffer from cyclic stresses, due to their sheer size and differing wind forces that fatigue the blades and bearings at a high rate.

Typical Wind Generator Construction

The most significant problem is blade stress, because as a blade reaches the top of its arc it is subject to more wind pressure than at the lowest point of its arc. The huge column on which the whole thing is mounted interrupts the wind flow and as the blade passes, it is subject to ‘negative’ stress (or momentary wind load relief). these two factors combined exert great strain on the blade, its mounting, and the bearings. This problem alone caused many of the earlier models to fail quickly.

Just as important is the fact they are unsightly, and do we really want to cover every high point on the planet with wind turbines?

The Enercon E-126

The highest output from a wind turbine (the Enercon E-126) is a mere 7.58Mw, and that’s on a good day, for as we all know, the wind is a fickle thing. Germany’s nuclear power stations generate 20,490Mw of power per year, that’s 26.1% of total energy needs compared with 6.5% fulfilled by wind power from its in excess of 21,163 wind turbines. No! I am afraid wind is not the answer, no matter what the pundits say.

Energy From the Sun?

The sun is a constant source of energy, at least during daylight, but to generate our needs from solar panels would require covering half the country, and then you wouldn’t be able to use the lights after sundown. No! I don’t think that is practical either.

There are those who say we should burn bio-fuels or resort to hydro-electric power sources but the fact is, bio-fuels have ready proven to be a dead duck because the ground required to grow them is also needed to grow food. The problem with hydro-electric  is, not all countries have rivers or coastline.

The Only Other Viable Alternative?

So the bottom line is, we continue to use fossil fuels that are slowly destroying our planet, or we go with the nuclear option, at least for the foreseeable future. Your choice!

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