1) Weather, climate, and climate change impact all activities in the electricity sector, from demand forecasting to power production and pricing. 2) Accurate demand forecasting requires accounting for temperature and other climate factors, but demand patterns are changing due to climate change. 3) Water resources face strong variability and climate change impacts hydroelectric production forecasts and capacity planning.

1. ImpactS of Weather,
Climate and Climate
Change on the
Electricity Sector
Laurent DUBUS, EDF R&D
Thanks to my colleagues Marta Nogaj, Sylvie
Parey, Viviane Leboucher, Joël Gailhard, Anne
Dupeyrat and Thierry Jouhanique

2. Weather, climate and the electricity sector
management
Means, distributions
and extremes of climate
parameters affect all
the activities
2 © EDF Energy Week 2009 - The World Bank, Washington, D.C., March 30 - April 2, 2009

3. Management of the Offer/Demand balance
A complex and multi-scaled problem
Clients & Prices
volatility (Markets)
Power Prices
Stocks management
forecasts
(coal, fuel, oil)
Environmental
Rules
Demand
forecasts
Offer/Demand balance
Weather & Climate Optimization
Electricity can
not be stocked
Hydro-Electricity
Networks management
Production forecasts
Renewables
Production Units
Production Maintenance
Heterogeneity
forecasts scheduling
3 © EDF Energy Week 2009 - The World Bank, Washington, D.C., March 30 - April 2, 2009

4. Electricity Demand forecasting : why is it so
important ?
Daily to weekly, monthly and seasonally : need to estimate future power demand in
order to manage power production and to forecast market electricity prices
February 2005 courtesy www.rte-france.com
Power demand
Temperature
Temperature
anomaly
In France, power demand is highly dependent on temperature.
in winter : -1°C dT 1700 MW of extra production (2100 MW in 2009)
in summer : +1°C dT 400-500 MW of extra production
4 © EDF Energy Week 2009 - The World Bank, Washington, D.C., March 30 - April 2, 2009

5. Demand / Today:
forecasts using temperature & cloud cover
Use of Météo-France & ECMWF deterministic and probabilistic forecasts
… integrated in demand forecasting tools, to allow
the management of production units plannings
buy & sell decisions on electricity markets
5 © EDF Energy Week 2009 - The World Bank, Washington, D.C., March 30 - April 2, 2009

6. Demand / Tomorrow:
Evolution of HDDs in France
j =14 / 04
∑ (18°C − T )
HDD =
j =15 / 10
Average HDD (year
2000)
Winter HDDs (15 oct-14 april) with an 18°C threshold
The yearly average number of HDDs decreases for all the models
but the amplitude of the decrease depends on models, scenarios
and regions
2050-2000 2100-2000
(mean of all models) (mean of all models)
IPCC A2
scenario
~ -25% on France by the end of 21st century
~ -10% on France by mid 21st century
6 © EDF Energy Week 2009 - The World Bank, Washington, D.C., March 30 - April 2, 2009

7. Demand / Tomorrow:
Impact on demand : case study for Agen (SW of France)
Simulations for futur :
• A2 Scenario, ARPEGE model
• Mean differences between 2070-2100 and 1960-1990
• Agen nearest grid point
Agen - Scenario A2
Climate parameters for demand in buildings
Temperature increase
• 2m temperature
• Solar flux No trend on solar flux
~700 km
• Relative humidity Relative humidity reduces in summer
Case study
An office building with heating and cooling needs
Impact of climate evolutions for the same building (no renovation considered) :
Heating - 58%
• Decrease of heating needs
• Increase of cooling needs Cooling + 64%
• Differences (in %) are similar to the actual ones between Agen and Strasbourg
7 © EDF Energy Week 2009 - The World Bank, Washington, D.C., March 30 - April 2, 2009

8. Water resources : a strong interannual variability
& a forecasting challenge
Effects of a warm year on the
arrival of water in dams stocks
Daily variations of french hydro power production capacity in 2003
Floods …
Drought & heat
wave
Dry spring / early
Good winter ! and quick melting
8 © EDF Energy Week 2009 - The World Bank, Washington, D.C., March 30 - April 2, 2009

9. TOOLS SERVICES
Hydro / Today
Power production forecasts
OBSERVATIONS
Providing of real-tile
1200 points
hydro-meteo data for
operating
Real Time
Monitoring & assistance
24h a day
Hydrometeo
MODELING (Hydrology-
Centers
Water Temperature
Short term forecasts
And/or
D to D+8
•Daily hydro-meteorological bulletins (6
forecaster’s expertise
days a week)
•Warning on detection of exceeded
thresholds or flood
Adaptation to
•Warning in case of dangerous weather
the operating phenomenon (storm, snow …)
needs •Water temperature forecasts bulletins
QUANTITATIVE FORECASTS
Air Temp, Precips, Wind
Long term forecasts
Several weeks
•Dams inflow forecasts
•Forecasts of France hydro-
power production capacity
•Lowest water levels forecasts
BASSIN: AIN-VALSERINE
4 35
Date de la prévision 19/02/99 60%
20% 60% 90% Max Moy 20%
J 0 5 22 7 30 90%
J+1 0 16 33 14 Ma
17 28
J+2 0 14 Mo
J+3 5 16 31 14 25
J+4 3 14 24 11
J+5 5 17 34 16
20
J+6 3 12 15 9
15
10
5
0
J J+1 J+2 J+3 J+4 J+5 J+6
9 © EDF Energy Week 2009 - The World Bank, Washington, D.C., March 30 - April 2, 2009

10. Hydro / Today
Long term (seasonal) forecasts can be improved
Cumulated inflow on
700
700
the melting period
Q obs
600
600
Q mod
500
500
Flow (m3/s)
400
400
Hydrological model 300
300
200
200
Observations 100
100
(Temp, precipitations,
Tomorrow : longer
pression …) 0
lead times forecasts ? 1-mar
1-jan
1-janv 1-feb 1-mars 1-apr 1-may 1-jun 1-jul
1-févr 1-avr 1-mai 1-juin 1-juil
Probabilized inflow
distributions
900
Archives T, Precip 800
Inflow (mm)
Production
Inflow 700
management
forecasts
tools 600
500
0.0 0.25 0.5 0.75 1.0
10 © EDF Energy Week 2009 - The World Bank, Washington, D.C., March 30 - April 2, 2009

11. Hydro / tomorrow
La Loire in 2050-2060
gien 1971-1998 gien enveloppe 70% gien médian
900
Higher winter flows
800
(floods ?)
700
Qm interannuel (m3/s)
600
Earlier and stronger low
500
water levels (-40%)
400
300
200
100
0
Actuel enveloppe 70% médian
26
1 2 3 4 5 6 7 8 9 10 11 12
mois
24
22
Flow at Gien
20
Tmoy interannuelle (°C)
18
Present
16
Abut 50% of the
air temp anomaly
14
Future mean
in found in water
12
temp
Dispersion
10
Water temp (6 simulations)
8
@Dampierre
6
4
1 2 3 4 5 6 7 8 9 10 11 12
mois
11 © EDF Energy Week 2009 - The World Bank, Washington, D.C., March 30 - April 2, 2009

12. Hydro / tomorrow
Winter
Summer
Julien Boé, CERFACS
Autumn
Spring
Relative change of water flow between 2046/2065 and
1970/1999 (scenario SRES A1B, ARPEGE model)
12 © EDF Energy Week 2009 - The World Bank, Washington, D.C., March 30 - April 2, 2009

13. Wind speed and wind power production forecasting
RMSE-France
13 © EDF Energy Week 2009 - The World Bank, Washington, D.C., March 30 - April 2, 2009

14. Impacts of climate change
Multi-model mean change of 10m average windspeed and anomaly vectors
2046-2065 (Ref 1971-2000)
UV10 Hybrid downscaling UV10 Statistical downsc. UV10 Large scale simul.
Julien Najac, CERFACS
Winter
Relative
change (%)
Summer
14 © EDF Energy Week 2009 - The World Bank, Washington, D.C., March 30 - April 2, 2009

15. Rising / future needs
Wind power production (inshore & offshore)
Solar (thermal & PV)
Marine energies
Pollution monitoring and atmospheric
dispersion modeling
15 © EDF Energy Week 2009 - The World Bank, Washington, D.C., March 30 - April 2, 2009

16. Summary & Conclusions
By the past we learnt to work with weather forecasts for
Demand forecasts
Hydropower and reservoirs' management
Today we need observed data and forecasts
Climatological data, weather forecasts & climate scenarios
Locally and globally
For many variables (temp, precip, wind, heat fluxes, sea level …)
With quantification of uncertainties
For designing & building facilities, and operating them
The rising use of renewables implies a rising importance of weather,
water and climate parameters (marine & atmospheric)
16 © EDF Energy Week 2009 - The World Bank, Washington, D.C., March 30 - April 2, 2009

17. Synthesis: expected impacts at the end of 21st
century
Key need :
Projections in the near future (now to 2030-2040)
at regional scales
17 © EDF Energy Week 2009 - The World Bank, Washington, D.C., March 30 - April 2, 2009

18. Monthly to seasonal and annual time scale : a
technical challenge, a major financial interest
Key need :
Demand Better climate, power demand and production
forecasts Production needs
capacities forecasts @(15 days to several months) lead
time
Resource forecasts Production capacities
Example : during a cold wave in January
with lakes full
should I use the water to produce now
expecting that precipitations in spring
and autumn will fill them again
or should I buy energy on the market
and keep the water to face a dry summer ?
?
$
Figures: ECMWF
18 © EDF Energy Week 2009 - The World Bank, Washington, D.C., March 30 - April 2, 2009

19. Thank you for
your attention
Contact:
laurent.dubus@edf.fr
EDF R&D
Département Mécanique des Fluides, Energies et
Environnement
Groupe Météorologie Appliquée et Environnement
Atmosphérique
6 Quai Watier - BP 49
78401 CHATOU CEDEX

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20 © EDF Energy Week 2009 - The World Bank, Washington, D.C., March 30 - April 2, 2009