Academy highlights contradiction in French policy

21 April 2017

France cannot achieve a significant reduction in emissions of greenhouse gases from electricity production while also reducing the share of nuclear in its energy mix, the country's Academy of Sciences says.

France's National Assembly gave final approval in July 2016 of the country's Energy Transition for Green Growth bill. The overall objectives of the bill include: a 40% reduction in greenhouse gas emissions by 2030 and a 75% reduction by 2050, compared with 1990 levels; halving overall energy consumption by 2050 compared with 2012; increasing renewable energy's share of final energy consumption to 32%; and cutting the share of nuclear in electricity generation from almost 75% to 50% by 2025.

In a 19 April statement, the Academy of Sciences suggested the debate about France's energy transition was incomplete. "In reality, energy policy programs should take better account of physical, technological and economic constraints," it said. "In the current debate, our fellow citizens might be led to believe it would be possible to develop renewable energy as a way to decarbonise the system while removing both fossil fuels and nuclear."

"Nuclear energy is objectively the most effective way to reduce the share of fossil fuels in the production of electrical energy."

French Academy of Sciences

The variability in output from wind and solar energy requires the use of other forms of energy to offset this intermittency, the academy said. "One might think that energy exchanges at the European-level could mitigate this problem, but long nights are everywhere at the same time in Europe, and anticyclones are often with us and our neighbours simultaneously."

Energy storage solutions for vast amounts of electricity produced by renewable sources are not yet available or are currently too expensive, the academy notes. In addition, the growth of intermittent renewable energy also requires significant extension of the electricity transmission network.

"Simple common sense leads one to conclude that production of electricity that can meet the country's needs requires the availability of 'on demand' energies, which do not suffer from intermittency and which can be called upon at all times," it said. This means, in the absence of energy storage solutions, significant use will need to be made of thermal and nuclear power plants if France is to increase its use of renewable energy.

Nuclear power last year accounted for 13% of electricity production in Germany, which decided in 2011 to phase out its use of this form of energy. In 2010, nuclear power had accounted for 22%. The academy noted that, even though renewable energy accounted for 30% of power production last year, the share of fossil fuels was unchanged at 55% because Germany has had to open new fossil fuel plants to provide the back-up required for intermittent renewable energy. Germany thus remains one of Europe's largest CO2 emitters.

France, through its high dependence on nuclear energy, is one of the lowest emitters of greenhouse gases per capita: about half as much as Germany. France produces around 540 TWh of electricity with emissions of 46 million tonnes CO2 per year, compared with Germany, which produces about 631 TWh from 334 million tonnes.

"Nuclear energy is objectively the most effective way to reduce the share of fossil fuels in the production of electrical energy," it said. "Within this general framework, there is a real contradiction in wanting to reduce emissions whilst reducing the share of nuclear power. In fact, many studies show that the total share of renewable energy cannot exceed 30-40% without leading to an exorbitant cost of electricity and the emission of greenhouse gases."

The academy said "realistic and coherent" scenarios show that it is impossible to have an energy system based wholly on renewable energy sources, which also "indicate a reasonable trajectory towards an energy solution where nuclear power will have its place in the coming decades".

In February, the French Nuclear Society issued a white paper stating the country needs to maintain its nuclear power generation capacity in order to raise the share of electricity from renewables without increasing the cost of electricity production.

Researched and written
by World Nuclear News