Dungeness Power Station

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1 Dungeness A
- 1.1 Closure and Decommissioning
2 Dungeness B
3 Ownership
4 Location
5 References
6 See also
7 External links

There are two nuclear power stations located near Dungeness in the south east of Kent, England.

[edit] Dungeness A

Dungeness A is a legacy Magnox power station, connected to the National Grid in 1965 and nearing the end of its life. It has two reactors producing 223 MW of electricity each, with a total capacity of 446 MW. Its reactors were built by The Nuclear Power Group and its turbines were built by Parsons. [1]

[edit] Closure and Decommissioning

It is due to cease power generation by the end of 2006. It is anticipated that defuelling would be completed by 2009, the turbine hall demolished in 2010 to be replaced by an intermediate level waste store in 2014. The waste store and reactor building would then be placed on a care and maintenance basis until 2103, with final site clearance and closure by 2111. Decommissioning is estimated to cost £1.2 billion. An alternative proposal has been made to accelerate cleanup for completion by 2030. [2]

[edit] Dungeness B

Image:Dungenesspowerstation.JPG

Dungeness B is an Advanced gas-cooled reactor (AGR) power station which began operating on 1983. It has two 600 MW reactors, producing an optimal capacity of 1200 MW (though actual output is 1110 MW [3]) and is due to be closed in 2018 [4]. Its reactors were built by Atomic Power Constructions and like the "A" station, its turbines were built by Parsons [5][6].

[edit] Ownership

Both stations were built by the Central Electricity Generating Board (a nationalised institution in the UK), but following privatisation they are now operated by two different companies (Magnox Electric, now part of The British Nuclear Group (BNG), and British Energy respectively).

[edit] Location

The stations are built on the largest area of open shingle in Europe, measuring 12 km by 6 km, which has been deposited by the sea and built up over thousands of years. The entire area is moving slowly north and east as the sea moves the shingle from one side of the ness to the other. It is surrounded by a nature reserve Site of Special Scientific Interest (SSSI). A fleet of lorries is used to continuously maintain shingle sea defences for the plant as coastal erosion would otherwise move shingle away at an estimated rate of 6 m per year. Around 30,000 cubic metres of shingle are moved each year. It seems that deposition on the north shore of the ness does not keep pace with demand. In all 90,000 cubic metres, including Dungeness, are moved each year along parts of the coast between Pett Level and Hythe. This is necessary for the safety of the entire area including the Power Stations. Approximately 100 million litres of cooling water is extracted and returned to the sea each hour, after being heated 12 degrees Celsius (22 °F).

Because of the need for continuous shingle replenishment and increasing sea levels, it is unlikely that the site will be used for any future nuclear power stations once the existing stations are closed.

The relation of the Power Stations with the ness in time is important. Geological history places the beginning of the promontory, some 3000 years ago, as shingle deposits offshore from Pett Level. From there the evidence suggests that the Ness enlarged and migrated up Channel to its present position.

Importantly the ness and the coastline between Pett Level and Hythe are volatile. In recorded history Walland Marsh to the west of the Power Stations has been flooded. In the space of sixty years severe inundation occurred bringing the sea inland to Appledore and the original mouth of the River Rother from north of the ness at Romney to the south at Rye Harbour. The site is a few metres above Mean Sea Level and would be isolated in the event of flooding of the magnitude that submerged big areas of East Anglia and Holland in 1953. Conjecture says that the ‘hurricane’ of 1987 did not bring the sea to the actual stations because there was a low tide at the time. In 1990 the sea is reported to have reached the gates of the A station and the compound of the National Grid switch house next to the B Station. With the possibility of global warming, more frequent and powerful storms and their associated waves and surges could be possible. They may increase the instability of the ness.

[edit] References

Eddison, J (2000). Romney Marsh Survival on a Frontier. Tempus. ISBN 0-7524-1486-0. Page 139 also reports the 1990 flooding mentioned above. Page 139 also reports the 1990 flooding mentioned above.
Romney Marsh. Retrieved on 5 February, 2006.
Kent Against a Radioactive Environment. Retrieved on 20 March, 2006.
British Energy. Retrieved on 16 April, 2006.
industcards. Retrieved on 16 April, 2006.
Going Critical. Retrieved on 16 April, 2006.