* 50 nations operating, building, planning nuclear
* EDF alone will need 10 bln eur for new safety measures
By Nina Chestney and Karolin Schaps
LONDON, March 8 A year after the Fukushima nuclear accident most of the world continues running and building nuclear power, but extra risk control measures imposed in the wake of the disaster will increase the cost of operating nuclear plants.
Japan's reactor meltdowns at the Fukushima nuclear plant triggered by a deadly earthquake and tsunami on March 11 last year shook the nuclear world and raised a question mark over whether atomic energy is safe.
After the accident, Germany, Switzerland and Belgium decided to move away from nuclear power altogether to grow reliance on renewable energy instead.
But nearly 50 other countries operating, building or planning to construct nuclear plants continue to do so, albeit facing higher costs.
"EDF in France will have to spend 10 billion euros ($13.12 billion) to take into consideration things not needed before to prepare for a beyond-design basis accident," said Francois Perchet, technical advisor at the World Nuclear University and formerly employed at the French utility.
EDF said on Thursday it would carry out upgrades to improve safety in its nuclear fleet in the next ten years, earlier than previously planned.
In the United States, nuclear operators will be expected to spend an additional $1 million per reactor to account for additional post-Fukushima safety arrangements, said John Ritch, director general of the World Nuclear Association based in London.
Fires and explosions in the Fukushima Daiichi nuclear station caused a full meltdown in three reactors while a fourth was also damaged.
Today, the four reactors are in a stable, cold shutdown state and clean-up of the site continues, but the final phase of decommissioning will not happen for 30 or 40 years.
Almost all of the Japan's 54 reactors sit idle, awaiting approvals to restart.
Nevertheless, planning for nuclear as a future source of energy continues. Over 60 nuclear plants are under construction worldwide - 39 of which are in China, India and Russia, according to a World Energy Council report on Thursday.
"The Fukushima accident has not led to any significant retraction in nuclear energy programmes in countries outside Germany, Switzerland, Italy and Japan," said Ayed Al-Qahtani, WEC's senior project manager.
"Progress in many national nuclear power programmes, especially in non-OECD countries, has been delayed, but there is no indication that their pursuit of nuclear power has declined."
EU operators are currently carrying out stress tests on nuclear plants imposed by the EU Commission to assess whether they would be vulnerable to events like natural disasters, terrorist attacks or aircraft crashes, the results of which should be available by the end of the summer.
Several EU member states are also doing their own, national tests.
After safety checks, more nuclear programmes will be rejuvenated and new investments will improve plants' safety so they can run for another decade or more, WEC said.
Safety concerns have also led to more demand for new types of reactors and for plant design to consider flooding as well as seismic risks and more realistic construction timescales.
"Outside the former USSR, the nuclear industry continues to be one of the safest industries in which to work and the safest way to generate most of the electricity the world needs," said retired nuclear safety specialist Don Higson.
But international coordination on safety could still be improved. At present, safety measures are overseen by national bodies and calls for an organisation such as the International Atomic Energy Agency to monitor action have gone unheeded. ($1 = 0.7622 euros) (Editing by Keiron Henderson)