DER and Microgrids: Research Topics within EU Framework Programs
Nikos Hatziargyriou
[email protected] National Technical University of Athens, Greece
CERTS, Berkeley 2005 Symposium on Microgrids, 17 June 2005
Sustainable Energy Systems DRIVING FORCES
Energy Policy:
Market liberalisation and competitiveness External dependency and security of supply Energy efficiency and technological development
Environment Policy:
Kyoto and Göteborg commitments for a sustainable development
R&D&T and innovation Policy:
Lisbon Strategy and the European Research Area CERTS, Berkeley 2005 Symposium on Microgrids, 17 June 2005
Sustainable Energy Systems Legislative instruments
Electricity internal market, 97/98 & 2003
Electricity from RES, September 2001
Energy efficiency in buildings, December 2002
Bio-fuels for transport, May 2003
Emission right trade, Oct 2003
Co-generation, February 2004 CERTS, Berkeley 2005 Symposium on Microgrids, 17 June 2005
Drivers for Energy Research in EU Security of supply ; 50% external dependence ; reliance on fossil fuels ; need diversification of sources (RES)
Climate change ; “one of the greatest challenges of our generation” ; energy Ù CO2 ; need clean energy (RES)
Competitiveness of the European industry ; competitiveness (Lisbon objectives) ; sustainable development ; energy is a growth market (RES) CERTS, Berkeley 2005 Symposium on Microgrids, 17 June 2005
Key considerations for “Electricity with large DER” Security of supply – efficient mix of centralised with decentralised operation allows the use of domestic energy resources, whilst maintaining a high level of reliability and quality of supply. Climate change – higher efficiency in energy transport and use of RES and cleaner Distributed Generation, incl. CHP, results in a real contribution to reduce emissions. Competitiveness of European Industry – enhancement and renewal of the electricity infrastructure networks represents a huge investment/markets, both in the EU and worldwide. CERTS, Berkeley 2005 Symposium on Microgrids, 17 June 2005
RTD Electricity in FP5-6: large scale“integration” of RES+DG Validation of advanced grid architectures Large Scale Virtual Power Plants Network of Excellence for DER laboratories Co-ordination Action for European DER Power electronics High Temperature Superconductivity Future European Electricity Transmission Networks CERTS, Berkeley 2005 Symposium on Microgrids, 17 June 2005
FP5 (1998-2002) funded research large-scale “integration” of RES+DG Research Area: INTEGRATION DER
Number of projects
Total Budget [M€]
EC funding [M€]
Distributed Generation
8
34.29
18.99
Transmission
4
9.74
5.72
Storage
20
45.31
20.73
HT Superconductors
6
11.27
6.16
‘Other’
17
29.12
15.21
TOTAL
55
129.73
66.81
CERTS, Berkeley 2005 Symposium on Microgrids, 17 June 2005
FP6 (2002-2006) funded research large-scale Integration of RES+DG Research Area: INTEGRATION DER
Number of projects
Total Budget [M€]
EC funding [M€]
Advanced Architectures and Operation concepts
7
65.50
33.35
Transmission
2
7.07
4.95
Storage
1
5.87
5.00
HT Superconductor Devices for networks
2
7.82
3.35
Advanced Power Electronics
2
5.25
3.41
TOTAL
14
91.51
50.06
CERTS, Berkeley 2005 Symposium on Microgrids, 17 June 2005
Main lessons learned so far FP5&6 funded research large-scale Integration of RES+DG
Non-technical issues are critical today Main technical issues are reliability, safety and quality of power Real-time information is critical Few possible concepts for smart power grids, but final solutions still unclear Impact on transmission networks should be further considered. Emerging results are being exploited International dimension recognized under ERA Co-operation and co-ordination of stakeholders in the context of a Technology Platform CERTS, Berkeley 2005 Symposium on Microgrids, 17 June 2005
Cooperation –– Collaborative Collaborative research research Cooperation 9 Thematic Priorities 1. 2. 3. 4.
T F RA
Health Food, agriculture and Biotechnology Information and Communication Technologies Nanosciences, Nanotechnologies, Materials and new Production Technologies
D
5. Energy 6. 7. 8. 9.
Environment and climate change Transport Socio-Economic Sciences and the Humanities Space and Security research CERTS, Berkeley 2005 Symposium on Microgrids, 17 June 2005
5.Energy Energy 5.
D
T F RA
Hydrogenand andfuel fuelcells cells Hydrogen Renewableelectricity electricitygeneration generation Renewable Renewablefuel fuelproduction production Renewable Nearzero zeroemission emissionpower powergeneration generation Near
Smartenergy energynetworks networks Smart Energysavings savingsand andenergy energyefficiency efficiency Energy Knowledgefor forEnergy Energypolicy policymaking making Knowledge CERTS, Berkeley 2005 Symposium on Microgrids, 17 June 2005
Preparation of FP7 Smart Power Networks: Research and demonstration needs for “Integration” of DER/RES.
¾ Aimed at removing all obstacles to larger development of DER/RES ¾ Ensure functioning of the EU electricity market, addressing the issues of security, reliability and quality of supply ¾ Provide appropriate knowledge for technical solutions and regulatory approaches. CERTS, Berkeley 2005 Symposium on Microgrids, 17 June 2005
Directorate General
5th (EC) RTD Framework Programme (1998-2002)
Research
“Integration of Renewable Energies + Distributed Generation” European Commission DG-Research Over 100 different organizations 34 Mio. Euro
Concentrating efforts and maximising critical mass Creating real European added value in support of European policy making towards mobilising research Identifying highest priority research topics in this field Improving links with CERTS, Berkeley 2005 Symposium on Microgrids, 17 June 2005 policies and schemes Source: M. Sánchez -Jimenez
Directorate General
Research
Cluster “Integration of Renewable Energies + Distributed Generation”
CERTS, Berkeley 2005 Symposium on Microgrids, 17 June 2005
What are MICROGRIDS? Interconnection of small, modular generation to low voltage distribution systems forms a new type of power system, the Microgrid. Microgrids can be connected to the main power network or be operated islanded, in a coordinated, controlled way. CERTS, Berkeley 2005 Symposium on Microgrids, 17 June 2005
Technical, economic and environmental benefits • • • •
Energy efficiency Minimisation of the overall energy consumption Improved environmental impact Improvement of energy system reliability and resilience • Network benefits • Cost efficient electricity infrastructure replacement strategies • Cost benefit assessment CERTS, Berkeley 2005 Symposium on Microgrids, 17 June 2005
Energy Efficiency - Combined Heat and Power Prof. Dr. J. Schmid
100 % 50 % electrical energy power station 50 % unused waste heat
50 % fossil fuel
exchange of electrical energy
Up to now: • Central power stations • Decentral heat production In Future: • Decentral combined heat and power
100 % Oil / Gas
⇒ 1/3 less consumption of fossil sources of energy
CERTS, Berkeley 2005 Symposium on Microgrids, 17 June 2005
Potential for DG to improve service quality Voltage level
G
G
G
G
G
DG
Distribution of CMLs
Security of supply
G
Central generation
DG
Medium scale DG
DG
Small-scale DG
Security of supply
CERTS, Berkeley 2005 Symposium on Microgrids, 17 June 2005
Network Benefits – Value of Micro Generation ~ .02-.04 €/kWh
Central Generation
~.03-.05 €/kWh
Transmission HV Distribution
~ .05-.07 €/kWh
~.1-.15 €/kWh
MV Distribution LV Distribution
Micro Generation
CERTS, Berkeley 2005 Symposium on Microgrids, 17 June 2005
Technical Challenges for Microgrids • Relatively large imbalances between load and generation to be managed (significant load participation required, need for new technologies, review of the boundaries of microgrids) • Specific network characteristics (strong interaction between active and reactive power, control and market implications) • Small size (challenging management) • Use of different generation technologies (prime movers) • Presence of power electronic interfaces • Protection and Safety CERTS, Berkeley 2005 Symposium on Microgrids, 17 June 2005
Market and Regulatory Challenges • coordinated but decentralised energy trading and management • market mechanisms to ensure efficient, fair and secure supply and demand balancing • development of islanded and interconnected price-based energy and ancillary services arrangements for congestion management • secure and open access to the network and efficient allocation of network costs • alternative ownership structures, energy service providers • new roles and responsibilities of supply company, distribution company, and consumer/customer CERTS, Berkeley 2005 Symposium on Microgrids, 17 June 2005
MICROGRIDS Project “Large Scale Integration of Micro-Generation to Low Voltage Grids Contract : ENK5-CT-2002-00610 GREAT BRITAIN • UMIST • URENCO
PORTUGAL
GREECE
14 PARTNERS, 7 EU COUNTRIES
• EDP • INESC
UMIST URENCO
SPAIN
• NTUA • PPC /NAMD&RESD • GERMANOS
GERMANY
ISET SMA
• SMA • ISET
ARMINES
• LABEIN
EDF
NETHERLANDS
FRANCE
CENERG
• EMforce INESC EDP
LABEIN ICCS / NTUA GERMANOS
• EDF • Ecole des Mines de Paris/ARMINES • CENERG
PPC/NAMD&RESD
http://microgrids.power.ece.ntua.gr CERTS, Berkeley 2005 Symposium on Microgrids, 17 June 2005
R&D Objectives – Contribute to increase the share of renewables and to reduce GHG emissions; – Study the operation of Microgrids in normal and islanding conditions; – Optimize the operation of local generation sources; – Develop and demonstrate control strategies to ensure efficient, reliable and economic operation; – Simulate and demonstrate a Microgid in lab conditions; – Define protection and grounding schemes; – Define communication infrastructure and protocols; – Identify legal, administrative and regulatory barriers and propose measures to eliminate them; CERTS, Berkeley 2005 Symposium on Microgrids, 17 June 2005
Microgrids Highlights • Control philosophies (hierarchical vs. distributed) • Energy management within and outside of the distributed power system • Device and interface response and intelligence requirements • Permissible expenditure and quantification of reliability benefits • Steady State and Dynamic Analysis Tools
CERTS, Berkeley 2005 Symposium on Microgrids, 17 June 2005
Microgrids – Hierarchical Control MicroGrid Central Controller (MGCC) promotes technical and economical operation, interface with loads and micro sources and DMS; provides set points or supervises LC and MC; MC and LC Controllers: interfaces to control interruptible loads and micro sources PV MC
Flywheel AC DC
LC
DC AC MC
MC
AC DC
LC
Storage LC MC
~ CHP
DMS DMS
MV
LV MC
MGCC MGCC MC AC DC
~
LC
Fuel Cell AC DC
Centralized vs. Decentralized Control
Micro Turbine
CERTS, Berkeley 2005 Symposium on Microgrids, 17 June 2005
MultiAgent System for Microgrids • • • •
Autonomous Local Controllers Distributed Intelligence Reduced communication needs Open Architecture, Plug n’ Play operation DNO
• FIPA organization • Java Based Platforms • Agent Communication Language Grid Level
Agent
MO
......
Management Level Agent
Agent
Agent
Microgrid
Microgrid Microgrid
MGCC
LC LC
LC
LC ...
Field Level
Agent Agent Agent Agent
CERTS, Berkeley 2005 Symposium on Microgrids, 17 June 2005
Participation of Microgrids in Energy Markets • Microgrid Serving its own needs using its local production, when financially beneficial (Good Citizen) MGCC minimises operation costs based on: – Prices in the open power market – Forecasted demand and renewable power production – Bids of the Microgrid producers and consumers. – Technical constraints
• Microgrid buys and sells power to the grid via an Energy Service provider (Ideal Citizen) MGCC maximizes value of the Microgrid, i.e. maximizes revenues by exchanging power with the grid based on similar inputs CERTS, Berkeley 2005 Symposium on Microgrids, 17 June 2005
20 kV 20/0.4 kV, 50 Hz, 400 kVA
Off-load TC 19-21 kV in 5 steps
uk=4%, rk=1%, Dyn11 3Ω
3+N
0.4 kV
Overhead line
Circuit Breaker
4x120 mm2 Al XLPE twisted cable
instead of fuses
Pole-to-pole distance = 35 m
Study Case LV Feeder with DG sources
Single residencial consumer
3+N+PE 4x6 mm2 Cu 20 m
3Φ, Is=40 A Smax=15 kVA S0=5.7 kVA
80 Ω
Possible neutral bridge to adjacent LV network
80 Ω 80 Ω
Flywheel storage Rating to be determined
30 m
Circuit Breaker Possible sectionalizing CB
80 Ω
Group of 4 residences 3+N+PE
3Φ, 15 kW
~
3Φ, 30 kW
3Φ, 30 kW
3+N+PE
~ ~
~
Appartment building 3+N+PE
5 x 3Φ, Is=40 A 8 x 1Φ, Is=40 A Smax=72 kVA S0=57 kVA
80 Ω
4x6 mm2 Cu 20 m
30 Ω
Fuel Cell
Microturbine
20 m
1Φ, 4x2.5 kW
1 x 3Φ, Is=40 A 6 x 1Φ, Is=40 A Smax=47 kVA S0=25 kVA
2Ω
10 Ω
4x25 mm2 Cu
Photovoltaics
Appartment building
80 Ω
3x70mm2 Al XLPE + 30 m 54.6mm2 AAAC Twisted Cable 3x50 mm2 Al +35mm2 Cu XLPE
10 Ω
Wind Turbine
80 Ω
4x16 mm2 Cu
~
4 x 3Φ, Is=40 A Smax=50 kVA S0=23 kVA
Other lines
3+N
Single residencial consumer 3Φ, Is=40 A Smax=15 kVA S0=5.7 kVA
3+N+PE 80 Ω
80 Ω
1+N+PE
3+N+PE
Photovoltaics 1Φ, 3 kW
4x16 mm2 Cu 30 m 80 Ω
30 Ω CERTS, Berkeley 2005 Symposium on Microgrids, 17 June 2005
LV network with multiple feeders 20 kV 20/0.4 kV, 50 Hz, 400 kVA
Off-load TC 19-21 kV in 5 steps
uk=4%, rk=1%, Dyn11 3Ω
3+N
0.4 kV
Overhead line 4x120 mm2 Al XLPE twisted cable
3x250 A
Underground line
3x160 A
Pole-to-pole distance = 35 m
Single residencial consumer
3x160 A
3x150 mm2 Al + 50 mm2 Cu XLPE cable
Pole-to-pole distance = 30 m
3+N
4x35 mm2 Al conductors
3+N
3Φ, Is=40 A Smax=15 kVA S0=5.7 kVA
3Φ, Is=40 A Smax=20 kVA S0=11 kVA Possible neutral bridge to adjacent LV network
80 Ω 80 Ω
Residential load
80 Ω
80 Ω
Overhead line 4x50,35,16 mm2 Al conductors
3+N
80 Ω
3Φ, Is=63 A Smax=30 kVA S0=16.5 kVA
80 Ω
2Ω
4x50 mm2 Al conductors
80 Ω
200 m Twisted Cable 3x70mm2 Al XLPE + 54.6mm2 AAAC
1Φ, Is=40 A Phase: a Smax=8 kVA S0=4.4 kVA
4x1Φ, Is=40 A Phase: abcc Smax=25 kVA S0=13.8 kVA
4x16 mm2 Al conductors
80 Ω
Appartment building
Group of 4 residences
5 x 3Φ, Is=40 A 8 x 1Φ, Is=40 A Smax=72 kVA S0=57 kVA
4 x 3Φ, Is=40 A Smax=55 kVA S0=25 kVA 80 Ω
1 x 3Φ, Is=40 A 6 x 1Φ, Is=40 A Smax=47 kVA S0=25 kVA
Commercial load
50 Ω
Single residencial consumer
Appartment building
Industrial load
3Φ, Is=40 A Smax=15 kVA S0=5.7 kVA
80 Ω
Workshop 3Φ, Is=160 A Smax=70 kVA S0=70 kVA
80 Ω 80 Ω
80 Ω
2x1Φ, Is=40 A Phase: ab Smax=16 kVA S0=8.8 kVA
1Φ, Is=40 A Phase: c Smax=8 kVA S0=4.4 kVA
4x1Φ, Is=40 A Phase: abbc Smax=25 kVA S0=13.8 kVA
4x35 mm2 Al conductors
80 Ω
80 Ω
3x1Φ, Is=40 A Phase: abc Smax=20 kVA S0=11 kVA
CERTS, Berkeley 2005 Symposium on Microgrids, 17 June 2005 80 Ω
Highlight: MGCC Simulation Tool
CERTS, Berkeley 2005 Symposium on Microgrids, 17 June 2005
Residential Feeder with DGs Good Citizen Cost Reduction : 12.29 % 27% reduction in CO2 emissions
kW
Model Citizen Cost reduction : 18.66% 90 80 70 60 50 40 30 20 10 0 -10 -20 -30
Load & Power exchange with the grid (residential feeder)
1
2 3
4 5
6 7
8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
Hour Pow er exchanged w ith the grid
Load Pattern
CERTS, Berkeley 2005 Symposium on Microgrids, 17 June 2005
Environmental Benefits • Average values for emissions of the main grid • Data about emissions of the µ-sources. 27% reduction in CO2 emissions due to policy1 Maximum reduction in CO2 emissions 548kgr/day- 22.11% higher cost
CERTS, Berkeley 2005 Symposium on Microgrids, 17 June 2005
Highlight - Permissible expenditure to enable islanding Customer Sector:
Residential
Commercial
=
1.4 £/kWpk
15 £/kWpk
Net present value =
15 £/kWpk
160 £/kWpk
Annual benefit
Peak demand
=
Perm. expenditure = MicroGrid (2,000kW)
2 kW
1000 kW
£30
£160,000
£30,000
£320,000
CERTS, Berkeley 2005 Symposium on Microgrids, 17 June 2005
Highlight: Reliability Assessment ¾ System Maximum Load Demand:
188 kW
¾Capacity of System Infeed:
210 kW (100%)
¾Installed DGs: 15 kW Wind, 13 kW PVs, 30 kW Fuel Cells, 30 kW Microturbines
FLOL (ev/yr)
LOLE (hrs/yr)
LOEE (kWh/yr)
Infeed Capacity 100% (no DGs)
2,130
23,93
2279,03
(no DGs)
58,14
124,91
3101,52
Infeed Capacity 80% (with Wind + PV)
14,02
41,67
2039,41
Infeed Capacity 80% (all DGs)
2,28
Infeed Capacity 80%
15,70
CERTS, Berkeley 2005 Symposium on Microgrids, 17 June 2005
716,36
Reliability Assessment – continued FLOL (ev/yr)
LOLE (hrs/yr)
LOEE (kWh/yr)
31,08
2313,77
Infeed Capacity 90% (no microsources)
8,52
Infeed Capacity 90%, system load 207 kW (+10%) (no microsources)
44,10
Infeed Capacity 90%, load 207 kW (with Wind + PV) 11,35 Infeed Capacity 90%, load 207 kW (all microsources) 2,305
92,75 36,69 16,55
3073,84 2232,54 911,68
CERTS, Berkeley 2005 Symposium on Microgrids, 17 June 2005
Parallel operation of inverters f
u
f0
u0
∆f
-1
0
Frequency droop
1
P PN
-4%
∆u
-1%
-1
0
1
Q QN
Voltage droop
- Droops for synchronising inverters with frequency and voltage - Frequency and voltage of the inverter is set according to active and and reactive power. CERTS, Berkeley 2005 Symposium on Microgrids, 17 June 2005
Voltage Regulation and Active Power control through droop - Applied droop concept is based on inductive coupled voltage sources. - In a LV-grid components are coupled resistive, thus voltage determines the active power distribution - There are two effects of droops - direct (inductive coupling) - indirect (resistive coupling)
u
f
u0
f0 ∆f
-1
- The „indirect“ effect requires droops, which have the same sign for the frequency as well as the voltage droop and therefore the stable operation point is „in phase“.
0
The compensation of lines was simulated and is recommendable. Overcompensation has to be avoided! 1P -1 1Q 0 on Microgrids, 17 June 2005 PCERTS, Berkeley 2005 Symposium Q ∆u + 4%
+ 1%
N
N
Development of Electronic Switch 400
420
440
460
480
500
520
540
560
580
600
560
580
600
v MicroGrid [v]
300
0
-300 100 80
grid connected
60
island
IMicroGrid [A]
40 20 0 -20 -40 -60 -80 -100 1000 800 600 400
IGrid [A]
200 0 -200 -400 -600 -800 -1000 400
420
440
460
480
500
time [ms]
520
540
CERTS, Berkeley 2005 Symposium on Microgrids, 17 June 2005
Highlight: Modelling and Simulation
Two battery invs + two PVs + one WT - Isolation + wind fluctuations
P,Q per phase Battery Inverter A
I per phase Battery Inverter A
CERTS, Berkeley 2005 Symposium on Microgrids, 17 June 2005
MORE MICROGRIDS Advanced Architectures and Control Concepts for More Microgrids Proposal/Contract no.: PL019864 MANUFACTURERS MANUFACTURERS(8) (8)
RESEARCH RESEARCHINSTITUTES INSTITUTES&& UNIVERSITIES UNIVERSITIES(6) (6)
SIEMENS SIEMENS(D) (D) ABB ABB(S) (S) SMA SMA(D) (D) EMforce EMforce(NL) (NL) GERMANOS GERMANOS(GR) (GR) ANCO (GR) ANCO (GR) ZIV ZIV(ES) (ES) I-Power I-Power(UK) (UK)
ICCS/NTUA ICCS/NTUA(GR) (GR) UMIST UMIST(UK) (UK) INESC INESCPorto Porto(PT) (PT) ISET (D) ISET (D) LABEIN LABEIN(ES) (ES) ARMINES ARMINES(F) (F)
UTILITIES UTILITIES&& MICROGRID MICROGRIDOPERATORS OPERATORS(7) (7) EDP EDP(PT) (PT) CRES CRES(GR) (GR) CONTINUON CONTINUON(NL) (NL) MVV MVV(D) (D) CESI CESI(I) (I) ELTRA ELTRA(DE) (DE) LRPD LRPD(PL) (PL)
Total Budget 7.9 M€ EC Contribution 4.5M€
CERTS, Berkeley 2005 Symposium on Microgrids, 17 June 2005
MORE MICROGRIDS Workpackages • • • • • • • •
WPA. Design of micro source and load controllers for efficient integration WPB. Development of Alternative Control Strategies (hierarchical vs. distributed) (emphasis on De-centralized – MAS technologies) WPC. Alternative Microgrids Designs WPD. Technical and Commercial Integration of Multi-Microgrids WPE. Standardization of Technical and Commercial Protocols and Hardware WPF. Field trials on actual Microgrids (7 Installations) WPG. Evaluation of the system performance on power system operation (Germany, Italy, Denmark, Netherlands, UK, Portugal, Greece, Poland…) WPH. Impact on the Development of Electricity Infrastructures (expansion Planning) (Germany, Italy, Denmark, Netherlands, UK, Portugal, Greece, Poland…) CERTS, Berkeley 2005 Symposium on Microgrids, 17 June 2005
Pilot Kythnos Plant PV-Generator
=
~
PV-Generator
= =
=
~
~
~
AC- Grid: 3~ 400 V
~
=
~
Battery
=
~
~
=
PV Diesel MORE
=
~
=
Battery PV-Mode
~
=
PV
AC Grid: 3~ 400 V
PV-Generator =
~
Supply of 12 buildings (EC projects MORE and PV-Mode) CERTS, Berkeley 2005 Symposium on Microgrids, 17 June 2005
The Kythnos Microgrid
CERTS, Berkeley 2005 Symposium on Microgrids, 17 June 2005
The Kythnos Microgrid
CERTS, Berkeley 2005 Symposium on Microgrids, 17 June 2005
Conclusions • Microgrids: A new paradigm for future power systems • Distinct advantages regarding efficiency, reliability, network support, environment, economics • Challenging technical and regulatory issues • Needs for Field Testing and Benefits Quantification http://microgrids.power.ece.ntua.gr CERTS, Berkeley 2005 Symposium on Microgrids, 17 June 2005
