The delays and cost over-runs at the nuclear plants under construction in the US, France and Finland have been so extreme that they seem more likely to be a Monty Python sketch than reality.

EDF’s 1.6GW Flamanville 3 project in northern France was supposed to cost €3.3bn and start commercial operations in 2012, yet its latest cost estimate is €10.9bn — more than treble the initial budget — and it is not now due to be completed until the second quarter of 2020, eight years behind schedule.

Similarly, the 1.6GW Olkiluoto 3 reactor in Finland was originally planned to be finished by May 2009 at a cost of €3bn, but it is now set to cost about €8.5bn and not be completed until January 2020 — almost 15 years after construction began.

And the 2.3GW Vogtle 3 & 4 project in the US state of Georgia, which had a budget of $14.3bn and was scheduled to be completed by April 2017, is now set to cost more than $27bn, with a latest completion date of November 2022.

The UK’s own controversial 3.2GW Hinkley Point C plant, which is scheduled to be completed by EDF in 2025, will cost £20.3bn. EDF will receive a guaranteed £92.50 (at 2012 prices) per MWh produced over 35 years. Offshore wind prices are already around half that amount, yet Hinkley will still be receiving that price for all its power in the year 2060. It is no wonder that the UK’s independent National Audit Office condemned the contract as a “high cost and risky deal”.

So why is the cost of new nuclear be rising at a time when the price of renewables is falling?

“Those projects in the West that have suffered delays and cost increases aren’t typical of new build worldwide,” says World Nuclear Association analyst Jonathan Cobb. “ The projects in France, the US and Finland are the global exception, rather than the norm. They are only four reactors under construction out of 55 reactors under construction worldwide.

“They are facing similar issues of being first-of-a-kind [FOAK] construction, with the challenge of gaining regulatory approval for the new design and establishing a supply chain to support reactor construction, in addition to the normal challenges FOAK construction can bring.”

He adds: “Costs have been failing in countries [such as South Korea and China] where programmes of construction have continued and good construction performance have been achieved.”

Demand for new nuclear is stronger in developing nations, mainly in Asia, that have fast-growing demand for electricity and may also suffer from coal-related pollution, Cobb points out, before adding that these are also more forward-thinking.

“Markets in Western Europe and the US currently don’t take a long-term view, [and] fail to recognise the full externalities and system costs of different forms of electricity generation,” Cobb complains. “The growth in the production of shale gas in the US has had a major impact on that market, as has the dash for gas elsewhere. Gas offers carbon benefits over coal, but in the long term, gas can’t be a significant player in the generation mix if we are to achieve a truly low-carbon generation mix. For that we will need all low-carbon technologies working together.”

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