Climate Sense

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EDF’s perspectives on adaptation

to climate change and variability

Laurent Dubus and Sylvie Parey, EDF/R&D

n its last assessment report published in 2007,

Intergovernmental Panel on Climate Change (IPCC)

confirms the observed evolution of climate since the beginning

of the last century. It is attested not only through the temperature

increase, but also through the evolution of other linked param-

eters, such as the melting of ice and snow cover or the elevation

of sea level. The significant influence of anthropogenic activities

on these evolutions is now also recognised as ‘very likely’ and

will probably continue in the future. Furthermore, changes and

impacts at the regional level have been expected since the last

2001 report – with Europe, for example, anticipating an increase

in the frequency and intensity of heat waves, combined with an

increased drought risk during the summer in south and central

Europe, whereas, winter precipitations could increase in north-

ern Europe. EDF will then have to deal with the effect of these

modified conditions on electricity production and distribution,

together with changes in energy consumption linked to both

climatic evolutions and climate change mitigation measures. The

consumer behaviour may then evolve in response to the shift in

climate conditions, for instance with less heating needs in winter,

but potentially more cooling needs in summer. Furthermore, they

could be incited to convert thermal heating installations, such

as fuel or gas, to electricity, which for EDF could mean higher

demand in winter despite the temperature increase.

For these reasons, important research projects are running at EDF/R&D

in order to better estimate the climate change impacts on EDF activities,

as well as make better use of weather forecasts at different time-scales.

However, EDF’s needs outstrip the capabilities of current climate

models, especially concerning the spatial and temporal scales of the

impacts. The adaptation of power plants or networks to new climatic

conditions necessitates a precise as possible knowledge of said condi-

tions on the local scale of the facilities. Furthermore, protection of

installations or adaptation of crisis plans requires information on the

possible evolutions of meteorological extremes, which current climate

models still fail to correctly reproduce, especially at the local scale.

For this reason studies are being conducted to carefully analyse the

evolutions in mean, as well as in variance and extremes of the climate

variables, and their possible links, beginning with hot and cold temper-

atures.

For the operation of the system on time-scales from one day to

one year, several weather parameters are needed to forecast demand,

hydropower and production of other renewable energies, as well as

electricity prices. Short to medium-term numerical weather predictions

already provide useful information, but improvements are needed to

increase quality on the providers’ side, as well as to make better use

of such forecasts – especially in probabilistic approaches on the users’

side. A major need is to develop and improve forecasts

from two weeks to one or more years and to replace the

current practices based on the use of historical data. This

is a big technical challenge, but also very significant in a

financial sense.

Means of action in adaptation

EDF envisages climate change adaptation in differ-

ent ways. Recent meteorological events like the 2003

heat wave or the 1999 wind storms lead to the adop-

tion or revision of respective crisis management plans.

These plans are a first step in the adaptation to climate

events, which, at least for the heat waves, could be more

frequent in the future. The so-called plan aléas clima-

tiques (climatic risks plan) foresees a list of actions to

be taken in order to manage and to anticipate future

extremes in the best possible conditions. For example,

a large number of seaside power plants are now planned

to run during the summer, as they are less sensitive to

heat wave conditions. Furthermore, river temperature

forecasts are currently conducted in the summer in

order to anticipate potential cooling problems and then

adapt the production plan consequently, or activate any

other possibility to balance the supply and demand.

On the other hand, EDF uses the most robust results

of international research projects in order to begin the

adaptation of the currently running production facilities

– especially nuclear power plants. As the most likely

climate change impact concerns increase in tempera-

ture and heat wave frequency, EDF has started a broad

re-evaluation of its running nuclear facilities into how

they might be affected by high temperature conditions

in the summer. These new evaluations are based on

a proposed evolution of the statistical extreme value

theory, which allows the identification and extrapola-

tion of recent trends in high temperature extremes in

order to derive future very rare high temperature levels.

From such an exercise, conducted at EDF/R&D for both

air and water temperature, it is possible to verify if safe

production would still be possible under these potential,

very high temperature levels. If a facility falls short in this

area the necessary modifications are made. Concerning

the planning of new facilities; their initial proportions

now incorporate climate change considerations. Here

again, methodologies are worked out and proposed to

derive rare levels of high temperatures possible at the

daptation

and

itigation

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