The document discusses the integration of renewable energy sources (RES-E) and the associated demand for flexibility in power systems. It analyzes flexibility options for managing network constraints and balancing generation and demand, highlighting the role of storage, demand-side management, and sector coupling. The findings suggest that while additional flexibility options are available, existing systems can provide sufficient flexibility without hindering the deployment of RES-E.

1. www.oeko.de
Flexibility Options for RES-E Integration
Dr. Dierk Bauknecht, David Ritter
Leonardo Energy Webinar
17 March 2015

2. 2
www.oeko.de
From RES-E development to system integration
Leonardo Energy Webinar | 17.03.2015 | Bauknecht, Ritter
RES-E
increases
System
Integration and
Transformation
More Flexibility
Demand
A differentiated analysis is required:
• Flexibility demand
• Flexibility options
• Effects of flexibility
• and their evolution.

3. 3
www.oeko.de
Analysis of flexibility is based on two models
Dispatch model PowerFlex for
Germany
By Öko-Institut
Written in GAMS, CPLEX solver
Detailed modelling of various of
flexibility options within German
No flexibility demand as a result of
network constraints within
Germany
European network model
By energynautics
European exchange
as a flexibility option
Scenario:
EU Roadmap
Diversified Supply

4. 4
www.oeko.de
Flexibility options between networks and markets
1. Flexibility options to manage network constraints
• To what extent can storage and demand side management
(DSM) replace network upgrades?
• How often will these options actually be called from network
operators?
2. Flexibility options to balance generation and demand
• Storage and DSM should primarily be dispatched based on
market signals.
 How can network and market requirements be coordinated?
Leonardo Energy Webinar | 17.03.2015 | Bauknecht, Ritter

5. 5
www.oeko.de
Residual load
Demand
RES-E generation
Residual load
Residual load curve shows the amount of capacity that is needed on top of
RES-E per hour.
The capacity can be positive or negative.
Subtracting the electricity generated by variable renewable power plants from
the demand leads to the residual load curve.
Leonardo Energy Webinar | 17.03.2015 | Bauknecht, Ritter

6. 6
www.oeko.de
Residual load duration curve
Only Demand
and RES-E
Leonardo Energy Webinar | 17.03.2015 | Bauknecht, Ritter
Modelled
residual load -
incl. flexibility
already in
place
What are the functions and values of additional flexibility?

7. 7
www.oeko.de
Different flexibility functions and values
Deficit:
Flexibility can
replace plant
capacity
Surplus:
Flexibility substitutes
conventional
generation
Supply = Demand:
Competition with existing flexibility options by
1) Increased efficiency
2) High value from replacing fossil with RES-E
generation
Leonardo Energy Webinar | 17.03.2015 | Bauknecht, Ritter
hours per
year
GW

8. 8
www.oeko.de
Which options can be used?
Deficits:
New flexible
power plants
Load Management
(Reduction)
Import
Surplus:
Flexibilization of power plants
Load Management (Increase)
Use of „excess energy“ in other
sectors
Export
RES-E curtailment
Supply = Demand:
Load Management (Shifting and Reduction)
Storages with high efficiencies;
Flexible cogeneration
Competition with present options via variable
cost or efficiencies
Shifting surpluses to deficits
Storage and load management (shifting)
Virtual storages
Leonardo Energy Webinar | 17.03.2015 | Bauknecht, Ritter

9. 9
www.oeko.de
Residual load duration curve for Germany
Leonardo Energy Webinar | 17.03.2015 | Bauknecht, Ritter
40 % RES-E 60 % RES-E 75 % RES-E 100 % RES-E
Hours of the year [h]
No significant peak reduction
More hours with RES-E surplus

10. 10
www.oeko.de
Development of flexibility demand: deficit and surplus,
Existing flexibility; no import and export
Leonardo Energy Webinar | 17.03.2015 | Bauknecht, Ritter
-80
-60
-40
-20
-
20
40
60
1 1001 2001 3001 4001 5001 6001 7001 8001
GW
Hours
ca. 40% RES-E ca. 61% RES-E ca. 75% RES-E40 % RES-E 60 % RES-E 75 % RES-E

11. 11
www.oeko.de
Scenario 2030 for Germany, ca. 60% RES-E
Leonardo Energy Webinar | 17.03.2015 | Bauknecht, Ritter
748
7.275
1.464
8.394 4.308 1.210 2.869 2.004
-1.0022.170 1.327 0
- -
-
2.000
4.000
6.000
8.000
10.000
12.000
14.000
16.000
18.000
20.000
MW
Reduction of flexibility demand
Used potentials
Not used for deficit reduction

12. 12
www.oeko.de
Linking the electricity sector to other sectors
Power-to-Gas, Power-to-heat etc often seen as a way to provide
flexibility to the electricity sector.
However, it is mainly a way to use renewables in other sectors.
• This needs to be done in a flexible way.
Linking sectors can also lead to additional inflexibility, e.g. limited
flexibility of heat demand profile.
Systems that can use power and other sources are preferable,
e.g. power-to-heat.
If additional consumers are introduced too early, there is a
danger of increasing conventional sources
 L2H: Lignite-to-heat
Leonardo Energy Webinar | 17.03.2015 | Bauknecht, Ritter

13. 13
www.oeko.de
Economic ranking of options
What is the cheapest combination of options to meet flexibility
demand?
• Focussing on the capacity deficit
• 2030 snapshot
Result
• DSM, especially industry and commerce/trade/services
• CHP with heat storage
• Electric vehicles: Smart charging (needed anyway)
• Plus load curtailment for a few hours needed
Other combinations are possible – but storage not yet required.
Leonardo Energy Webinar | 17.03.2015 | Bauknecht, Ritter

14. 14
www.oeko.de
Full Costs of Flexibility Options
depending on full load hours
0
500
1000
1500
2000
2500
3000
3500
4000
4500
5000
1 1001 2001 3001 4001 5001 6001 7001 8001
DSM
Gas turbine
CAES
PHS
Battery
P2G H2
P2G CH4
Interruptible Loads
Reference:Öko-Institute.V.(2014).
Leonardo Energy Webinar | 17.03.2015 | Bauknecht, Ritter

15. 15
www.oeko.de
Flexibility Roadmap
Phase 1 Phase 2 Phase 3
Scenario year /
RES-E share
2020
ca. 40%
2030
ca. 61%
2050
ca. 75%
Flexibility
demand and
options
No deficits,
Very low surpluses
New flexibility
competes against
existing options
Relevant surpluses
and especially deficits
Sufficient flexibility
options available
Longer deficit periods
 long-term storage
Leonardo Energy Webinar | 17.03.2015 | Bauknecht, Ritter

16. 16
www.oeko.de
Conclusions
Adding RES-E capacity increases the demand for flexibility.
 Flexibility options should be developed.
However, RES-E flexibility is not a bottleneck that should slow
down progress in setting up RES-E.
• A lot of flexibility can be provided by the options already in
place, i.e. mainly conventional plants.
•  lower full load hours!
• There are a number of additional options available in current
systems that can be exploited to cover that demand.
• Flexible CHP, Power-to-heat, DSM
• especially when electricity exchange between MS is used
Leonardo Energy Webinar | 17.03.2015 | Bauknecht, Ritter

17. 17
www.oeko.de
Contact
Dr. Dierk Bauknecht
Senior Researcher
Öko-Institut e.V.
Postfach 17 71
79017 Freiburg
Telefon: +49 761 45295-230
E-Mail: d.bauknecht@oeko.de
Leonardo Energy Webinar | 17.03.2015 | Bauknecht, Ritter