Agency of ecologic transition.....


The Regulated Access to Legacy Nuclear Power mechanism (accès régulé à l’électricité nucléaire historique) grants to retailers the right to purchase part of EDF’s production at a set price. The price and volumes are set by the regulator (CRE)


The Nuclear Safety Authority (Autorité de sûreté nucléaire) is the public entity which carries out, on behalf of the French state, the missions of nuclear safety control, radiation protection (workers in the nuclear industry, environment, local communities) and the public’s information, “to protect workers, patients, the public and the environment from the risks associated with nuclear activities”.

Adjusted (for weather and/or calendar effects) consumption

The consumption that would have been observed if temperatures had been normal (as defined below “Normal temperatures”) and excluding the consumption of 29 February for leap years.

Ancillary services

Automatic frequency containement reserve


Consumption, by a consumer, of all or part of the electricity generated by their own production installation. Closely related to the English-language concept of “prosumer”.


Production, by their own production installation, of all or part of a consumer’s electricity consumption. Closely related to the English-language concept of “prosumer”

Balance responsibility party

Balance responsibility parties are participants in the power system (retailers, consumers, traders…) who enter in a contract with RTE which obligates them to ensure that load and injection are equal within their so-called “balancing perimeter”. When the sum of all of the parties’ balances is not zero, RTE activates the various balancing capacities (adjustment mechanism and ancillary services). The balancing costs are then passed on to the parties which were unbalanced within their perimeter.


Carbon dioxide equivalent – a comparative emissions measurement index of different greenhouse gases representing their global warming potential. The volume of gas emitted is converted into the equivalent quantity of carbon dioxide needed to reach the same global warming potential.

Capacity factor

For a given production type, the capacity factor is defined as the ratio between production and installed capacity. In RTE’s Electricity report, the monthly and yearly capacity factors correspond to the monthly or yearly average of the half-hourly capacity factors. 


Climate is a statistic on long time scales of meteorological conditions (from a few months to a few million years) for a given region. Example: oceanic climate, temperate climate…

Combined-cycle gas turbine plant

A technology consisting of the association of a steam turbine and a gas turbine, which results in a better heat rate than conventional gas turbines.


Capacity calculation and market coupling region. The member countries are: France, Germany, Belgique, the Netherlands, Austria, Slovenia, Poland, the Czech Republic, Slovakia, Croatia, Hungary and Romania.

Coverage rate

The ratio between the output of a given generation type, and demand. In the Electricity review, the monthly and yearly coverage rates correspond to the average of half-hourly coverage rates.

Demand peak

The hours where electricity demand is highest

Dispatchable production unit

A production unit which can be started up and/or modulate its output on demand (thermal and nuclear power plants, hydroelectric plants with pumped storage…).


One of the power exchange operator among those designated by regulators. Power exchange operators are tasked with the organisation of market coupling, and provide insurance for transactions on the day-ahead and intraday markets. The operators approved for France by the Commission de régulation de l’énergie are EPEX SPOT and Nord Pool.


The European Pressurized Reactor, or EPR, is a nuclear reactor design of the pressurized water reactor (PWR) type. The EPR is part of the so-called 3rd generation of PWR


Means of production, consumption or other (storage type) that can be modulated up or down for the needs of the electrical system or its operation

Forward markets/prices

Prices negociated long ahead of delivery, the date of which can be far away, for periods ranging from a week to a year.

Fossil-fired themal/fossil fuels

Electricity generation from thermal power plants running on gas, coal or oil.

Grand Carénage

An large industrial programme designed to upgrade the safety of existing nuclear plants

Gross consumption

Countrywide electricity consumption (Corsica included, overseas territories not included), taking into account transmission losses but not the consumption of pumped-storage plants

Heat wave

In France, we speak of a heat wave when the temperatures observed are high day and night for at least three days in a row. The alert thresholds are defined locally based on thirty years of daily mortality data and various meteorological indicators (minimum temperature, maximum temperature, etc.). As part of meteorological vigilance, account is taken of the exceptional nature of nighttime temperatures.

Imbalance settlement

Financial transaction whereby RTE passes on the system balancing costs to balance responsibility parties


Difference between injection and load within the perimeter of a balancing entity (balance responsibility party).

Intraday prices

The prices of electricity transactions for delivery on the same day


Liquefied natural gas


Loi de programmation énergie-climat, French for Energy-climate programmation law

Lock hydropower plants

Mostly located in lakes downhill from mid-altitude mountains, those plants have a filling duration of 2 to 400 hours. They provide daily or, more rarely, weekly flexibility to the power system (daily demand peak, between business and non-business days…).

Low-carbon electricity

Electricity resulting from the conversion of non-fossil primary energy (renewables, nuclear…)


Manual frequency restoration reserve : Power reserves that help RTE balance the system



The French demand-respond products trading mechanism (Notification d’Échange de Bloc d’Effacement)


Nominated Electricity Market Operators

Other hydro power plants

The plants in the “other” category are tidal energy plants and pumped-storage plants.Tidal energy plants harvest the energy from the tides in coastal areas where the tidal range (the height difference between high- and low-tide) is large. This range is used to generate electricity by exploiting the height difference between two basins separated by a dam. Pumped-storage plants, operating in pumping-generation cycles between a downhill and an uphill reservoir, thanks to reversible turbines-pumps, are efficient storage assets which contribute to the balance of the power system. When the reservoirs also have natural inflows, the turbine is categorized as “mixed pumped storage”, otherwise as “pure pumped storage”.


The French Multiannual Energy Plan (Programmation Pluriannuelle de l’Énergie)

Physical / commercial exchanges

Commercial exchanges are the result of a commercial transaction bewteen market participants which are located in different countries (or bidding zones). Physical exchanges account for the actual electricity flows on interconnectors between countries, and can differ from commercial exchanges


Replacement reserve

Renewable thermal and waste

Electricity generation from thermal power plants running on fuels such as: bioenergy, paper waste, renewable household waste, non-renewable household waste…

Reservoir hydropower plants

Located downhill from mid- and high-altitude mountains, those plants have a filling duration of over 400 hours and provide seasonal flexibility and storage to the power system

Run-of-river hydropower plants

Mostly located in plains, those plants consist in a small-height dam and can be filled in under two hours. Therefore, their flexible potential is small and their production depends on the river’s flow rate.


Regional Schemes for the Grid Connection of Renewable Energy Sources (Schémas régionaux de raccordement au réseau des énergies renouvelables)


French Ten-Year Network Development Plan (Schéma décennal de développement du réseau)


French Strategy on Energy and Climate (Stratégie française énergie-climat)


National Low-Carbon Strategy (Stratégie nationale bas-carbone)


According to Météo France, the sunshine/sunlight duration is defined as the amount of time during which solar irradiance exceeds 120 watts per square meter.

Synchronous grid

Interconnected grid operating at the same frequency (e.g. the Continental Europe synchronous grid).


Trans-European Replacement Reserve Exchange


Internal tax on final energy consumption (taxe intérieure sur la consommation finale d’électricité

Temperature-sensitivity of consumption

Refers to the variation of electricity demand linked to the variation of temperature. For example, demand increases in winter, when the weather is cold, due to the high prevalence of electric heating in France

Températures normales

Average of past temperature timeseries that are considered representative of the current decade. They are based on Météo France data, and are computed by RTE at the country level thanks to a panel of 32 meteorological stations across France

Water reserves

Countrywide French water reserves represent the aggregate weekly filling level, in %, of reservoirs and lakes where there are hydropower production assets. Water reserves are expressed in terms of “producible energy”», in MWh, given the reservoir filling.

Wholesale prices

Can refer either to the spot price (cf. definition), or to forward prices, for which the delivery date ranges from the next week to the next year