Dr. Dipl.-Ing. Thomas Ackermann Energynautics, Germany E-Mail: t.ackermann@energynautics.com

STATUS OF HYBRID POWER SYSTEMS Summary of Hybrid Power System Workshop

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4th INTERNATIONAL HYBRID POWER SYSTEMS WORKSHOP

130 Participants

>20 Countries

16 Sessions

60 presentations

HISTORY – HYBRID POWER SYSTEMS WORKSHOP

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2016 Puerto Rico

2013 Hawaii

2019 Crete

2021 North Europe

2021 Caribbean

2020 Madeira

2018 Tenerife

WHY GREECE?

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• Kythnos • Ikaria • Tilos • Agios Efstratios • Symi • Megisti • Astypalea

HYBRID POWER SYSTEM

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A power system is understood as hybrid, if it consists of at least two different energy generation systems feeding an island load. A hybrid power plant is a system that consists of at least two different energy generation systems connected to an existing power system.

ENERGY MANAGEMENT SYSTEM (EMS)

Grid

EES

Smart Meter

CHP units

PV Charging Station

EMS

Inverter

Gateway

Communication Power

Customer 6

• Emissions • Noise • Maintenance Requirement • Diesel Storage/ Delivery? • High OPEX

• Reliable • Flexible to load fluctuations • Maintains System Stability • Lower CAPEX than renewables

DIESEL GEN-SET: A MUST?

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• 600 GW of diesel existing world-wide • Often a given component of a hybrid system

Kythnos is an island in the Western Cyclades with a population of 1.632 people and its 5-year Average Peak Demand is 3,1 MW. The island has been a pilot site for many innovative projects which have taken place on the island during the last three decades:

• 1998 - Installation of the new Vestas 500kW wind turbine • 2000 - Operation of a fully automated power system with 500kW battery

storage and a 500kW Wind Turbine • 2001 - Operation of a Microgrid electrifying 12 houses with intelligent

autonomous Load Control

• 1982 - Operation of the first Wind Park in Europe (5x20kW) • 1983 - Installation of a 100 kW PV system with Battery storage (400kWh) • 1989 - Replacement of the wind turbines (5x33kW) • 1992 - Inverters in the PV system

KYTHNOS I

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Source:

9 Kythnos Microgrid in Gaidouromantra, consists of 12 houses with PVs and Batteries (52 kWh), 9 kVA Diesel (only back-up), flexible loads (1-2 kW irrigation pumps) and Intelligent Load Controllers.

KYTHNOS II

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Source:

Siwa Oasis (Egypt) • Photovoltaic Diesel Hybrid System • Comissioned: March 2015 • PV Plant accounts for 30% of power Demand in Siwa city and surroundings

SUCCESSFUL RE INTEGRATION IN OFF-GRID SYSTEMS LOW SHARE OF VRE (~ 30%)

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Population 23,000

Load 17500 MWh/year

PV System 10 MWP (SMA Sunny Mini Central 7000HV) 5 systems (1 SMA Fuel Save Controlled and 4 manually controlled)

Diesel Generators 8 x 17.7 MW

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Population 3,877 (2015)

Load 1.6 MW average demand 2.3 MW peak demand

PV System 1.9 MWP (SMA Sunny TriPower 25000-TL-30; SMA Fuel Save Controller)

Diesel Generators 4 MVA

ESS (batteries) 1 MW/ 580 kWh (SMA Sunny Central Storage SCS 1000)

SUCCESSFUL RE INTEGRATION IN OFF-GRID SYSTEMS HIGH SHARE OF VRE PEAK SHARE 80%

St Eustatius Island (Caribbean) • Hybrid Solar/Diesel System with energy storage • 100% Fossil fueled until 2015: operational cost represented over 75% of electricity supplier‘s

income • Commissioned : March 2016 • 23% fossil fuel consumption

reduction; 89% PV + battery penetration observed

SUCCESSFUL RE INTEGRATION IN OFF-GRID SYSTEMS

12 Source: International Hybrid Power Systems Workshop 2016: Caribbean Largest PV-Diesel-Storage System STt Eustatius (Phase 1). SMA.

St Eustatius Island (Caribbean) • Example of operation window with reduced diesel generation

AGIOS EFSTRATIOS – “GREEN ISLAND” PROJECT

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Law 4495/2018 authorizes the Ministry of Energy, RAE and HEDNO to take all necessary actions for the

implementation of the project.

Heating facilities

Batteries Wind turbines

PVs

Island’s Thermal

Station

Island’s Network

Source:

• Agios Efstratios is a small island in the North – East part of the Aegean Sea, with only 270 inhabitants (2011) and its 5-year Average Peak Demand 0,32 MW.

• The project of Agios Efstratios includes two subprojects, the development of a Hybrid power plant and the development of a District Heating system (teleheating).

• The Hybrid power plant consists of Wind turbines (900 kW), PVs (150 kW) & Batteries (2,5 MWh), which is combined with a District Heating system (teleheating).

• The target of the project is to accomplish 85% energy of the island to come from RES.

• The project is funded by the EU, it is run by the CRES and it is still under study.

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EXAMPLE EL HIERRO, SPAIN WIND-HYDRO

1800 km

CANARY ISLANDS

95 km

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0,042 TWh

El Hierro

Tenerife

Spanish Mainland

ENTSO-E SIZE MATTERS

3,4 TWh ( X 80)

248 TWh ( X 6.000) or ( X 70)

3.278 TWh ( X 78.000) or ( X 1.000)

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Source:

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CHE:

• Owned by Gorona del Viento: • Cabildo de El Hierro • ENDESA • Instituto Tecnológico de Canarias

• Dispatched by the TSO

EL HIERRO ISLAND

Technical specs:

• Wind: 11.5 MW • Pumps: 6.4 MW • Turbines: 11.4 MW

• Upper reservoir: 380 dam3 • Lower reservoir: 149 dam3 • Roundtrip efficiency: 50%

Peak demand: 7 - 8 MW

Lowest demand: 3.5 – 4 MW

Source:

Wind Farm; 5 Enercon 2.3 MW turbines. Water reservoirs.

• Lined with high density polyethylene membrane

• Higher reservoir 380.000 m3

• Lower reservoir 149.000 m3 Penstocks.

• Turbine pipe of 2.3 km and 1 m of diameter

• Pump pipe of 3 km and 0.8 m of diameter • Hydro turbine station. 4 Andritz Pelton turbines of 2.83 MW (flow 0.5 m3/s) • Pump Station.

• 2 pump units of 1.6 MW (0.178 m3/s), controlled by frequency converters.

• 6 pump units of 0.54 MW (0.058 m3/s), started by 2 frequency converters

GORONA DEL VIENTO WIND HYDRO POWER PLANT

18 Sources:

• 8 consecutive days covering 100 % of the Island demand in June 2017

• 79 % of renewable integration into power system in July 2017

• 18 consecutive days covering 100 % of the Island demand in January-February 2018.

• Continuous improvement process.

• Stakeholders sharing information

• Gorona --> Plant improvements

• REE –> Operational changes

• ITC, Endesa, Enercon, Andritz.

OVERALL RESULTS

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Years Saved Diesel (tons) CO₂ reduction

(tons) Integration into

power system (%)

2015 (July to end

of year) 2099 4352.57 19.4

2016 5366 11629.56 40.7

2017 6070 13150.87 46.4

Sources:

STORAGE: CENTRAL HIDROEÓLICA DE EL HIERRO: 100% RENEWABLE

Longest run being 100% renewable:

25 Jan – 12 Feb 2018 (18 consecutive days)

100% RENEWABLES Source:

Wind Resource:

Wind Resource Energy integration into El Hierro power system

Jan. Feb. March April 66 % 57 % 49 % 71 %

OVERALL RESULTS Source:

Speed Governor Logic Wind farm Active Power setting treatment

Matlab library Governor diagram

ACTUATIONS – IMPROVEMENTS Source:

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CONCLUSIONS

Continuous analysis of the system. Collaboration between REE and Gorona is better for the system, because it is easy for the actors to detect, analyze and solve problems.

More confidence in the plant frequency regulation.

• 80 % of pump shedding reduction (more reduction with more than 2 Pelton Turbines dispatched)

• Performance increases Same system security with less pumps • It seems production increases

Source:

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NEXT STEPS

Synchronous compensator

• Response improvement (damper)

• Diminish water consumption

Wind farm

• FCU enhance

• Primary regulation

Short term forecasting; Machine learning

Source:

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EXAMPLE FAROE ISLANDS WIND-HYDRO-BATTERY

FAROE ISLANDS

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Identification of renewable resources

Average wind speed: > 10m/s Precipitation: > 1300 mm/year Tenerife: < 250 mm/year

Peak tidal velocities: ~ 3.5 m/s Average sun hours: ~ 1000 hrs/year Tenerife: ~3000 hours

FAROE ISLANDS

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0%

20%

40%

60%

80%

100%

116

933

750

567

384

110

0911

7713

4515

1316

8118

4920

1721

8523

5325

2126

8928

5730

2531

9333

6135

2936

9738

6540

3342

0143

6945

3747

0548

7350

4152

0953

7755

4557

1358

8160

4962

1763

8565

5367

2168

8970

5772

2573

9375

6177

2978

9780

6582

3384

0185

6987

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Hours with renewables only: 1576 h (66 days)

Hours with renewables

> 80%: 3288 h (137 days)

Hours with renewables

> 60%: 5508 h (230 days) Hours with renewables

> 40%: 6810 h (284 days)

hours

RENEWABLE ENERGY DURATION CURVE 2015

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∆P = -5.4MW in 60 seconds

EXTREME RAMP RATES (HÚSAHAGI WF)

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Control Inverter

2 Intensium Max 20P Energy 707 kWh

Continuous discharge power 2 400 kW

Continuous charge power 1 500 kW

Nominal voltage 623 V

Voltage range 525V – 700V

ENERCON E-Storage 2300 Apparent power 2300 kVA

AC Voltage LV: 400V MV: 20 kV

DC Power 2 400 kW

DC Voltage Range 345 – 705 V

DC Current 3325 A

60/20kV

WIND FARM BLOCK DIAGRAM

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BATTERY SYSTEM

-4

-2

0

2

4

6

8

0

2

4

6

8

10

12

MW

MW

Time scale: 18 minutes (data from September 1. 2017)

BESS Wind Farm Stabilized output

Battery discharging

Battery charging

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BATTERY SYSTEM IN OPERATION

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48,5

49

49,5

50

50,5

51

51,5

52

-101234567

Freq

uenc

y [H

Z]

Pow

er [M

W]

Sundsverkið M2-P Húsareyn HH-P Húsareyn BATT-P Húsareyn 20kV 2-f

Sudden drop of diesel unit

Drop of second diesel unit due to f<

BESS reacts on frequency drop

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FAST FREQUENCY SUPPORT FROM THE BESS

Foliennummer 1 History – Hybrid Power Systems WorkshopWhy Greece?Hybrid Power System Energy Management System (EMS) Diesel Gen-set: A Must?Kythnos IKythnos IISUCCESSFUL RE INTEGRATION�IN OFF-GRID SYSTEMS low share of VRE (~ 30%)Foliennummer 11SUCCESSFUL RE INTEGRATION�IN OFF-GRID SYSTEMSAgios Efstratios�– “Green Island” projectFoliennummer 14Canary IslandsFoliennummer 16Foliennummer 17Foliennummer 18Foliennummer 19Foliennummer 20Foliennummer 21Foliennummer 22Foliennummer 23Foliennummer 24Foliennummer 25Foliennummer 26Foliennummer 27Foliennummer 28Foliennummer 29Foliennummer 30Foliennummer 31Foliennummer 32Foliennummer 33