FACTBOX: European nuclear plant life extensions

(Reuters) - Most nuclear power plants have a nominal design lifetime of up to 40 years but many have been approved to operate for longer.

The possibility of component replacement and extending the lifetimes of existing plants are very attractive to utilities, given the high cost of constructing new nuclear plants and lingering public opposition to them, while some governments see them as a good way to limit carbon emissions.

But economic, regulatory and political considerations have led to the premature closure of some power reactors.

Below are details of those plants that have been granted life extensions in Europe:

BELGIUM

The Belgian government agreed in October to extend the lifetime of Belgium's three oldest nuclear power reactors by 10 years to 2025 to guard against energy shortages and help the budget.

Electrabel, the Belgian arm of GDF Suez, operates the Doel 1 & 2 nuclear reactors and the Tihange 1 reactor which were due to close in 2014-15.

CZECH REPUBLIC

A 10-year life extension to 40 years is under consideration for the Czech Republic's Dukovany power station. The four reactors at the plant began producing power from 1985-87.

FINLAND

Fortum's two units at Loviisa, which began commercial operations in 1977 and 1981, were originally licensed to run for 30 years but were given 20-year license extensions in mid 2007, which will allow them to run until 2027 and 2030, subject to safety evaluations in 2015 and 2023.

TVO's two 870 MW reactors at Olkiluoto began commercial operations in 1979 and 1982 and their lifetime has been extended to 60 years, subject to safety evaluations every 10 years, which means they will close in 2039 and 2042.

FRANCE

All 34 of France's 900 MW reactors, most of which were started in the late 1970s or early 1980s, had their lifetimes extended by another 10 years on July 7, 2009.

They were also granted 10 year extensions in 2002.

In October 2006 France's regulator cleared all 20 of the country's 1,300 MW reactors to run for another 10 years, providing some modifications are made during their 20-year outages planned for 2005-14.