RTE sees 'massive' thermal output needs without nuclear

France's need for new, decarbonised thermal generation power plants — using hydrogen and biogas — could be more than double existing gas-fired generation capacity by 2050 if the country phases out its nuclear capacity by then, according to a study published by RTE.

RTE, France's electricity transmission system operator (TSO), today published its future of energy outlook, focusing on six different scenarios for France to reach carbon neutrality by 2050.

The scenarios differ primarily around the availability of nuclear capacity. One scenario models a complete phase-out of French nuclear output by 2050 and another two assume that the existing fleet is maintained and makes up 13pc of the energy mix by 2050 (see table).

The low or no nuclear scenarios enhance the role of new, decarbonised thermal generation plants. These are needed to provide a flexible source of power generation to complement solar and wind.

The French energy system must be able to sustain several consecutive weeks without wind, "something which batteries or the intelligent management of demand will not be able to achieve", RTE said.

And hydroelectric stocks will be "insufficient" to meet this demand, leaving no other way than with nuclear power or thermal generation using decarbonised gas, RTE said.

In a 100pc renewables scenario, demand for decarbonised thermal generation would be "massive" at 29GW, with more thermal generation power stations than France has had since the 1970s, RTE said. This would also be more than double France's 12.6GW of existing gas-fired capacity.

But a French energy system with new nuclear capacity is more likely, based on existing government plans. French president Emmanuel Macron on 12 October announced the allocation of €1bn to the development of nuclear power, placing particular emphasis on small modular reactor technology.

Half of RTE's scenarios model the deployment of a new nuclear fleet, with up to 27GW in one variant — which would leave no need for thermal generation. Under this scenario new decarbonised thermal power stations would only rarely be run, and only as a "backup" for other sources, RTE said.

Each scenario assumes that France's electricity import capacity rises to 39GW by 2050 from 13GW at present to replace some of the lost flexibility in its domestic power mix. Hydroelectric capacity is 22GW, while marine generation capacity is between zero and 3GW, bioenergy is 2GW and pumped hydropower storage is 8GW.

RTE's energy consumption assumptions are based on the French national low carbon strategy, according to which total energy consumption slips to 930TWh by 2050 from 1.6PWh today.

By Auguste Breteau