RET_2015-01-02-03-04_Flipbook

Flexibility and demand: a distribution systems operator’s perspective - Joost Gottmer, EU affairs, EDSO for
Smart Grids
more socially-acceptable, as the impact of large constructions on public life and lengthy
permitting procedures is lessened.
1 WHAT IS FLEXIBILITY?
Flexibility can be defined as the ‘modification of generation injection and/or
consumption patterns in reaction to an external signal (price signal or activation) in
order to provide a service within the energy system. The parameters used to
characterise flexibility include the amount of power modulation, the duration, the rate
of change, the response time, the location, etc’ 3 .
Generation – modification of the generation injection itself
Demand – modification of the consumption pattern of the consumer
Storage – the modification of generation injection and/or consumption patterns by
storing it.
2 WHICH ARE THE BENEFITS OF FLEXIBILITY?
2.1 Technical and economic benefits
Flexibility services provided by distributed energy resources could bring a number of
quantifiable benefits at the distribution level, both for DSOs and grid users.
• Optimised distribution network capacity investments: Using flexibility could help
to defer an investment or could solve congestion when infrastructure
reinforcement is not an option. In the first case, the value of flexibility can be
calculated as the avoided return on capital cost over the deferral duration.
• Reduced technical losses: Flexibility services can also help to reduce network
losses that happen during the transport of electricity (kWh) from generators to
consumers. The value of flexibility then corresponds to the amount of electricity
that has not been lost.
• Reduced curtailment of distributed generation and reduced outage times: DSOs
could better control voltage profiles of RES, thereby enabling grid users (e.g. PV
owners) to feed-in more of their energy into the grid. The value represents the
avoided investments and maintenance costs in voltage control.
• Increased distributed generation hosting capacity: By helping to keep the network
stable, flexibility could increase the distributed generation hosting capacity of the
grid. The value represents the avoided investments and maintenance costs in
voltage control.
3
Based on EURELECTRIC definition in Flexibility and Aggregation: Requirements for their interaction
in the market (2014).
Revue E Tijdschrift – 131 ste jaargang/131 e année – n° 1-2-3-4-2015 (publication mars/publicatie maart 2017)
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