Visibility & Control

of distributed resources

SEERC TAC Workshop

“TSO & DSO Interaction in operation and planning”

Athens, 23 January 2020

Enrico Maria Carlini

Director of Dispatching and Operations

Phase out thermal capacity (GW) Target NECP

Installed wind and PV capacity (GW) Share of demand covered by RES1,3 (%) Minimum yearly reserve margin2,3 (GW)

RES in the electricity sector (%)

Self-consumption (TWh)

+27,5 GW

+~40 GW

20,7

10,7

Installed capacity by voltage level (%) Installed capacity (GW)

58

40 MW

available at

peak time

Italian Electricity System at a glance

2019

2

2018

29,1

6

2019

60%

42%

79%

27 Aprile

Ore 14:00

28 Aprile Giugno

UE ITALIA UE ITALIA (PNEC)

Quota di energia da FER

nei Consumi Finali Lordi

di energia

20% 17% 32% 30%

Riduzione dei GHG vs

2005 per tutti i settori

non ETS

-10% -13% -30% -33%

Obiettivi 2020 Obiettivi 2030

Share of energy from RES in gross final consumption of energy in 2030

2030 target for non-ETS GHG emissions under ESR compared to 2005

Hourly Daily Monthly

1) Including hydroelectric

2) Difference between the available production capacity and consumption (including the reserve) at the time of maximum load

3) Provisional data 2019

6%

18%

76% LV total capacity

MV total capacity

HV total capacity

28,4 GW

in MV e LV

Adequacy risks to meet peak

demand

National gross final consumption of energy (Mtep) RES share (%)

75,8 72,4 66,7 63,2 62,4 62,4 61,9

22,0 22,122,2 22,3 22,4 22,5 22,5

18,4 18,618,9 19,3 19,7 20,1 20,4

8,5 8,79,1 9,4 9,7 10,2 10,7

2013 2014 2015 2016 2017 2018 2019

[GW]

Thermal Hydro

Solar Wind

National Energy and Climate Plan (NECP): Italy by 2030

3

Decarbonization

The NECP targets a complete coal phase-out by 2025 and a significant push towards RES

20

30

Sc

en

ari

o

Ma

in t

arg

et

of

NE

CP

Installed capacity [GW]

Electricity production [TWh]

Coal phase-out by 2025 Growing RES share

177

123

46

49

17

40

24 75 6

7 19 16

290 310

2017 2030 PNIEC

Tradizionale Idroelettrico Eolico Fotovoltaico

Geotermica Bioenergie

RES:

113 TWh RES:

187 TWh

x3

x2,4

PV Wind Hydro

Bioenergy Geothermal

Traditional

9

6 1

46 50

4 4

19 19

10 18

20

51 5

5

117

148

2017 2030 PNIEC

Carbone Olio combustibile Gas naturalePompaggi puri Idroelettrico EolicoFotovoltaico Altre FER

RES:

~53GW

RES:

~93GW

Wind

Natural Gas Oil

Hydro

Other RES

Coal

Pumped Hydro

PV

NECP NECP

National gross final consumption of energy (Mtep) RES share (%)

The rise of Renewable sources: challenges

4

-10,000

0,000

10,000

20,000

30,000

40,000

50,000

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24

Demand Residual Load Renewables

50.000

40.000

30.000

20.000

10.000

0

-10.000

Demand Residual load Renewables

2030 scenario

The increasing penetration of renewables in the generation mix, combined with the simultaneous decommissioning of

conventional carbon-fired power plants is putting system operations at stress

1. Steep RAMPS for instance when the sun sets and the

contribution from PV falls

2. Reduced FREQUENCY REGULATION to automatically balance

supply and demand

3. GRID CONGESTIONS as wind-solar production is concentrated

most of all in the Centre-South area

4. Poor reactive power for VOLTAGE CONTROL coming from DG

connected to the distribution

5. ADEQUACY risks: lack of reserve margin to meet load at peak

time

6. OVERGENERATION when net load is negative or where wind

parks raise local congestions

7. Reduced INERTIA when less generators with rotating mass is in

operation

OPERATIONAL ISSUES RESIDUAL LOAD GROWING ISSUE

5

The rise of Renewable sources: solutions

GRID EXPANSION

• To strengthen connections between internal market zones and cross-border exchanges with neighboring

countries;

• Synchronous condensers for voltage regulation, inertia and short circuit level

MARKET DESIGN

• Power Purchase Agreement and tenders to finance RES investments

• Capacity market to give long-term price signals to ‘peakers’ unit

• Aggregation of demand, RES and storage to access Ancillary Services Market

STORAGE

• Additional 6 GW of storage capacity by 2030 to meet security, adequacy and flexibility* needs

DIGITALIZATION

• Data-exchange between TSO-DSOs to allow GD observability and controllability

• ICT infrastructure to capture distributed flexibilities

Focus in the

following

* Ramp up/ down at the sunrise/ sunset, downward regulation to accommodate the excess of non-dispatchable generation

Potenza totale BT

Potenza totale MT

Potenza totale AT/AAT

Qtà impianti BT

Qtà impianti MT

Qtà impianti AT/AAT

LV/MV Perimeter HV/HHV Perimeter

Structure of the current Italian production mix

Share1, per number and rated power2, of all the power plants distributed over the Italian national territory, sorted by primary energy source and kV

level:

1 Source: GAUDÌ, extraction performed in January 2019. 2 For the thermal source, the input power of the Production Units was considered (net of the part reserved for primary regulation), while for all the other

sources the nominal active power of the plants was considered.

Num [x1000] Pinst [GW]

799.4 7.3

1.3 0.1

4.7 0.2

1.7 0.1

0.02 0.001

807.3 7.7

Num [x1000] Pinst [GW]

22.6 11.7

2.6 3.3

0.6 1

4.0 4.7

0.02 0.002

29.9 20.7

Num [x1000] Pinst [GW]

0.1 1.1

0.4 23.2

0.3 9.1

0.3 54.1

0.03 1.0

1.3 88.5

Num [x1000] Pinst [GW]

822.2 20.1

4.3 26.7

5.7 10.3

6.1 58.9

0.1 1.0

838.4 116.9

Source

PV

Hydro

Wind

Thermal

Other

Total

LV MV HV / EHV Total

In Italy almost 1/4 of installed capacity is connected to the MV-LV distribution grid (≈28 GW).

Real-time telemetries from such DG are not acquired by Terna (for the time being).

Plant number distribution: Plant power distribution:

837 k plants 28.4 GW TOT

Qty of LV plants (96,3% of the Total)

Qty of MV plants (3,6% of the Total)

Qty of HV/HHV plants (0,1% of the Total)

LV total power

MV total power (17,7% of the Total)

(6,6% of the Total)

HV/HHV total power (75,7% of the Total)

Already today in Italy 25% of installed generation capacity is “DER”

6

100% monitored by Terna in real time 1 0% monitored by Terna in real time 2

The significant growth of RES connected to MV/LV, and the increasingly "active" role played by prosumers in the provision of flexibility, make

the observability of distributed resources of key importance for the TSO to manage properly the power system.

1 As defined by the IEC 60870 and 61850 standards, data acquisition takes place every 4 s via SCCT (Control and Conduction System). 2 Terna reads 3 times a day, for the purposes of forecasting, only the measurements of a subset of MT plants (ca. 200).

Direct observability and controllability of DER is fundamental for a safe operation

Controllability of grid connected DERs

PRODUCTION VHV/HV Ca. 1100 plants

NATIONAL TRANSMISSION GRID DISTRIBUTION GRID USERS

TRANSFORMER SECONDARY

SUBSTATIONS

(MV/LV)

PRIMARY

SUBSTATIONS

(HV/MV)

Ca. 2100

TRANSPORTATION

STATIONS

558 HYDRO

COIL

OIL

GAS

GEOTHERMAL

WIND

PV

BIOMASS

CROSS-BORDER

EXCHANGE

Distributed Generation LV (DG)

Ca. 800k plants

Agriculture

Tertiary

Domestic

Industry

Distributed Generation MV (DG)

Ca. 30k plants

Storage systems

The word «observability» refers to the ability to know in real time the main electrical data of the power system, in order to manage it correctly and

safely.

7

In the new energy context the observability of the DG becomes crucial for the secure management of the Electric System.

Most notably, the following applications will benefit from information of resources connected to the distribution networks:

Real-Time applications

Forecast applications

Ex-Post applications

Demand & RES forecast:

o Higher reliability in forecast data and nowcasting,

with consequent advantages for network security

and economy of operation

Reserves dimensioning :

o Lower dimensioning of the reserve quantities to be

purchased (e.g. replacement reserve - RR)

System Analysis

Turn Historical Data Into Predictions

Grid development, reporting

8

Grid calculation (static and dynamic regime)

o Estimation of system inertia in real time

o Early detection of dynamic instabilities and decision making support

Power flows optimization

o With the inclusion of DG data within the tools (eg OPF - Optimal Power Flow), improves the

computing of the DG enabled to Ancillary services market and the monitoring of its

performance.

Defense Plan

o Increased flexibility and effectiveness of the Defense Plan strategies

Real-time operations

o Optimizatimal activation of aFRR-automatic frequency restoration reserve in real time, with

consequent cost saving

o Fine tuning of wind energy curtailment to maintain system security

DERs observability positively impacts on multiple applications for system operations

Areas of application

Observability of grid connected DERs

Proposed model of observability and data exchange with DSO and SGU

Terna’s implementation model is based on a statistical-probabilistic approach characterized by:

An estimation "engine" developed and centrally managed by Terna, the only solution able to guarantee full visibility and awareness of the potential and the

limits to the reliability of the algorithm itself

Real-time acquisition of a suitable set of "sample" measures selected on the basis of their statistical relevance

The acquisition of other information necessary for the development, operation and evolutionary maintenance of the algorithm (real time and forecast

weather data, technical plant data, historical measurements)

The sample subset of DG consists of:

9

EHV/ HV connected

100% monitored by Terna in real time

100% real time estimation by Terna SCADA

and a sample of targeted measures

MV connected Direct Observability Perimeter

LV connected Direct Observability

Perimeter

100% real time estimation by Terna through upcoming central platform and a sample of

targeted measures

10

The model will be based on a combination of probabilistic techniques and algorithms with near real-time estimation and adaptative algorithms (i.e.

with “machine learning” features) which must be provided with a set of input data. In particular, input data can be classified into four main

categories:

Proposed model of observability and data exchange with DSO and SGU

• Direct and precise measurements of electrical parameters and real-time status

signals from a selected subset of DG Tele-measures

Tele-signals

Grid Master Data

• The model will be provided with the master data of the distributed generation plants

already available to Terna (GAUDI’ platform)

Historical data

• Electric data such as the energy produced by plants connected to LV and MV and

the exchange of active and reactive power flowing to the HV grid

• Time series are used for the continuous running of estimation models and for the

identification of statistical correlations between input data and target outputs

Meteorological data • Weather forecasts are key parameter for forecasting/estimating generation from

solar PV

11

Produced energy historical

series

Power-generating facilities

profiles and topological

configuration

Produced energy real-time

targeted measures [selection

of a DG plants sample on MV

/ LV networks]

Meteorological models and

real-time data

System Operator Applications

(Real–Time, Forecast, Ex-post

analysis)

Central platform: input data

processed by estimation

algorithm

INPUT OUTPUT

100% DG infeed estimated in

near real time

Conceptual framework

The total energy produced by renewable sources is estimated by metering a representative

subset of plants

Observability of grid connected DERs - Model

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Data collection and transmission model

Observability of DERs - Architecture

Output

State Estimator SCCT

DSO

SCCT

system for real

time operation

SCDM

Security, Control &

Defence System

SGD

ARC-GD

Defense System

SGD

Virtual

RTU

Computation

algorithms

HV

HV

MV + LV

MV – LV

HV

Other DG

installations

RTU/IED

Terna’s SCADA system dedicated to DG data to ensuring high level of flexibility and scalability for

future applications

Each DSO’s concentrator is provided with a virtual RTU1 dedicated to the data flow towards Terna’s

DG SCADA

(1) Today, each gateway is equipped with 2 virtual RTUs: one dedicated to the SCADA, one dedicated to the Defense Systems

TSO

Accuracy level

13

Minimum requirements – Key Parameters

Higher levels of accuracy: > 95% (target 98%)

Tightening constraints compared to «minimum requirements» allows for advanced applications

Accuracy level 3

Over 90%4

Run frequency for calculation 4

15 min

Systems Recovery Time

RTO2: 5 min; RPO3: 5 min

Electrical metrics of interest 1

Active and Reactive Power Production

DEFENSE SYSTEMS (BEST OPTION) REAL-TIME OPERATIONS, POWER FLOWS OPTIMIZATIONS,

GRID CALCULATIONS (MINIMUM REQUIREMENTS)

Aggregation level 2

Aggregation for Primary Substation distribution

Split type (PV, Wind, Hydro, Thermo, Other)

Run frequency for calculation

<5 min (target 1 min)

Systems Recovery Time 5

RTO2: 6 hh ; RPO3: 45 min

Observability of grid connected DERs - Model

1 Evaluated on 98° percentile | 2 RTO: Recovery Time Objective 3 RPO: Recovery Point Objective | 4 Measured on larger aggregation perimeters

14

BACK-UP

15

• Strengthening of North-South backbone and grid reinforcements

in the South of Italy and the Islands

• Foreign interconnections - Reinforcement and meshing of national

transmission grid

• Investments in voltage regulation and to increase the inertia

of the electricity system

• Capacity Market to deliver long-term price signal to encourage investments

in new efficient and flexible generation

• Power Purchase Agreements (PPAs) long-term power purchase contracts

for RES

• Long-term contracts through competitive procurement for storage capacity

• Participation of new flexible resources in ancillary services market, i.e.

demand, distributed generation, non-programmable renewable energy sources

and storage, including electric vehicle-to grid

• Evolution of the structure of the ancillary services market to cope with new

needs (voltage regulation, inertia,…)

• Digitalisation of the Transmission Grid (Assets and processes) and of its

control systems (data management)

• Full IoT, Energy Systems e Advanced Materials

• Sector Coupling

Transmission

grid

development

Long-term

price signals

Market

evolution

Innovation

and

digitalisation

1

2

3

4

Key enablers of the energy transition

16

• Demand Response

• Distributed Generation

• Non-qualified RES

• Storage (including EVs)

Potentially more than 800k

generation units and ca. 40 million

consumptions units

ca. 250 Generation

Units

• Relevant

qualified units

(P>10MVA)

ca. 250 Generation

Units

• Relevant

qualified units

(P>10MVA)

What is our strategy?:

• Increase the amount of resources able and available to provide grid services

• Diversify the portfolio of resources eligible for participation in ancillary services markets

• Enable the participation of new market players from outside the sector

… to a market with an higher degree of complexity From traditional resources…

Pilot Projects currently

under way Opening the Italian Ancillary Services Market to new resources

Markets evolution