Demonstration Project utilizing Hybrid Storage Battery System in the Oki-islands June 16, 2016 Power System Division The Chugoku Electric Power Co., Inc. Subsidized project of Ministry of the Environment
Demonstration Project utilizingHybrid Storage Battery System
in the Oki-islands
June 16, 2016Power System Division
The Chugoku Electric Power Co., Inc.
Subsidized project of Ministry of the Environment
1
1.Overview of the Oki-Islands
2Overview of the Oki-islands The Oki-islands are located in the Sea of Japan, about 50km to the north of
Shimane Peninsula. Composed of the “Dozen” and “Dogo” and about 180 small islands. The total area is about 350km2. A population is about 21,100 (Dozen: about
6,100, Dogo: about 15,000). Fisheries, agriculture and forestry, tourism are their major industries.
September 2013Certified as Global GeoparksNovember 2015
Global Geoparks confirmed as UNESCO Global Geoparks
Matengai(Nishinoshima)
Nishinoshima(Nishinoshima)
Nakanoshima(Ama)Chiburijima
(Chibu)
Dogo(Okinoshima)
【Dogo】【Dozen】
Rousokuiwa(Dogo)
The Oki-Islands
Oki-Islands UNESCO Global Geopark
(Source: Wikipedia, Japan natural location map with side map of the Ryukyu Islands.jpg)
3Electrical power supply facilities and demand in the Oki-Islands (Before start of project)
Dozen
Dogo
Saigo-Kuroki submarine power cable (22kV,18km)
Oki IslandsTotal capacity: 32.70MW+ wind, hydromaximum demand during 2012: 24.1 MW
DozenTotal capacity: 7.38 MWMaximum demand during 2012: 7.3 MW
DogoTotal capacity: 25.32 MW+ Wind, HydroMaximum demand during 2012: 16.8 MW
Kuroki Plant(internal combustion)
(7.38 MW)
2 internal combustion power plants(heavy oil diesel) “Saigo” and “Kuroki”, supply almost all the electricity with 22kV tie line.
Maximum Power demand is about 24MW,minimum is about 10MW.
Yui Plant (hydroelectric dam)
(0.2 MW)
Prefectural Ohmineyama Plant (wind)(Three 600-kW towers for 1.8 MW total)
Minamitani Plant(hydroelectric run-of-river)
(0.1MW)
Saigo Plant(internal combustion)
(25.32 MW)
4Renewable energy in the Oki-Islands(Before start of the project)
10.0
12.0
14.0
16.0
18.0
20.0
22.0
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
春(5月)夏(8月)秋(10月)冬(1月)
(MW)
wind power plant(1.8 MW)
Shimane PrefecturalBureau of Enterprise
hydroelectric plant(0.3 MW)
The Chugoku Electric Power
residential PV(about 0.8 MW)
(As of Jan. 2014)
Large fluctuations between seasons
(Surplus power generation will
occur during light-load seasons)
DemandCharacteristic
Large-scale introduction of renewable energy used to be difficult
(Hours)
Seasonal typical demand-curves in 2012Spring(May)
Summer(August)
Autumn(October)
Winter(January)
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2.Overview of demonstration Project utilizing
Hybrid Storage Battery System
6Challenges for large renewable energy
penetration in the Oki-Islands
6 129 15 18 21 243
Photovoltaic
Increase of Renewable energy〔MW〕
Use of surplus powerat night time
demand
Base-load generation
〔Hours〕
Renewable energy output fluctuation
Lack of frequency regulation capacity
Surplus power generated
Output fluctuation of REdue to such as a change in the
position of the sun
Output fluctuation of REdue to such as transit of cloud
Short term fluctuation Long term fluctuation
7Concept of Hybrid Storage Battery System
Problem
Simultaneous solution
Hybrid Storage Battery System
Coordination
Increase of Renewable energy
Output
TimeBase-load generation
Demandcurve
Renewable energy(existing)
[Fast and small fluctuation]ex.)Fluctuation
by passing cloud
[Slow and large fluctuation] → use PV output at night
ex.)Fluctuation by locating sun
Fast and small fluctuation↓
Small capacity and high-output
Lithium ion battery(Li-ion)
Slow and large fluctuation↓
Large capacity
Sodium-sulfur battery(NAS)
Sodium-sulfur battery(NAS)Lithium ion battery(Li-ion)
Countermeasure of short term fluctuation
Countermeasure of long term fluctuation
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西ノ島変電所
Period : From September 2015 to March 2019 (3.5 years) Items: ① Coordinated control between storage battery and diesel generation
② Charge/discharge control technology in order to take full advantage of the storage battery capacity
③ Output allocation of the lithium-ion and the NAS batteries
Dozen
Dogo
西ノ島変電所
Hybrid Storage Battery SystemType Output Capacity
NAS 4,200kW 25,200kWh
Li-ion 2,000kW 700kWh
Nishinoshimasubstation
Hybrid StorageBattery System
6,200kW
Large-scale PV Plant 2,000kW
NEW
NEW
NEW
NEW
NEW
Outline of the Demonstration Project
Prefectural Ohmineyama Plant (wind)(Three 600-kW towers for 1.8 MW total)
Minamintani Plant(hydroelectric run-of-river)
(0.1MW)
Saigo Plant(internal combustion)
(25.32 MW)
Yui Plant(hydroelectric dam)
(0.2 MW)Kuroki Plant(internal combustion)
(7.38 MW)
AmaPlant(wind)2,000kW
residential PV
500kW
Saigo-Kuroki submarine power cable (22kV,18km)
Large-scale PV Plants 3,000kW
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Aiming at 11MW of total renewable, by newly introducing 8.0MW in addition to the existing 3.0MW, by utilizing the storage battery system.
Renewable energy introduction plan
10
11
Demand Power supply
(M
W)
Minimum demand
Renewable energy
Operational required minimum
output of the internal-combustion
power
Supply and demand image at the time of the minimum demand
Storage battery absorb the surplus power generated by renewable energy
Renewable energy
facilities
Plan
〔MW〕
Record〔MW〕
As of March 31,
2016
Before the start
of the
demonstration
project
Wind power 1.8 1.8
Residential PVAbout
0.8About
0.8
Hydroelectric power 0.3 0.3
SubtotalAbout
3.0About
3.0
After the start
of the
demonstration
project
Large scale PVAbout
5.03.0
Wind power plant 2.0 0.0
Residential PVAbout
0.5About0.
3
SubtotalAbout
8.0About
3.3
TotalAbout
11.0
About
6.3
10
Site area:about 2,400㎡
Grid-connection equipmentTransformers 7,500kVA
NAS batteries4,200kW25,200kWh
PCS for NaS batteries
Control room
NaS batteries
Lithium-ion batteries
PCS for Lithium-ion
batteries
Grid-connection equipment
Installed facilities and equipments
The Nishinoshimasubstation
Lithium-ion batteries2,000kW700kWh
NaS batteries
NaS batteries
NaS batteries
Designed as compact as possible, considering safety measures for NAS characteristics and noise mitigation for neighbor residences.
11Benefits of hybrid scheme for storage battery system
Combination of different types of storage battery system
Initial cost reduction
about 30%
Improvement of charge/discharge management of NAS batteries
Improvement of system efficiency
Cost reduction
■In hybrid storage battery system, the frequency of SOC reset can be increased by sharing the absorbing capacity for RE output fluctuation between NAS and Li-ion battery, and SOC operational range is possible to expand.
■Reduction of auxiliary power consumption can be achieved by reducing the capacity of NAS battery, that improves the system efficiency of storage battery system.
■Combination of Li-ion and NAS battery can decrease construction cost, because ¥/kW of Li-ion and ¥/kWh of NAS are economical.
SOC Operational range
(NAS only : SOC reset once a week)
SOC Operational range
(Hybrid storage battery system: SOC reset twice a week)
Discharge end Charge end
Expandable Expandable
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Amount of acceptable renewable energy and the required power output and capacity of storage battery system have been determined by simulation.
Alternative No. 2 in following table was selected.
Optimal combination of the storage battery capacity
Alternatives
Output [MW] Simulation result
CostLi-ionBattery
NASBattery
Capacity of tie-line
Charging/Discharging fluctuation
Frequency deviation
No. 1 1.5 4.8
No. 2 2.0 4.2
No. 3 2.5 3.6
Battery Capacity within the range
Battery Capacity within the range
NAS Battery Capacity over the range
13Hybrid system configuration diagram
300V
290V
The PCS converts betweenDC and AC as well asprotects the facilities frompossible malfunctions ofthe power system.
DC/ACInverter(PCS)
DC AC
DC/ACInverter(PCS)
transmissionlines
Breaker
Switch gearMain transformer
Boost transformer
Lithium-ionbatteries
NaSbatteries
Li-ion (2,000kW) batteries are composed of 500kW unit × 5 set. NAS (4,200kW) batteries are composed of 1,200kW unit × 2 set
and 1,800kW unit 1 set.
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3.Balancing operation utilizing hybrid Storage Battery System
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EMS equipped in “Nishinoshima substation” performs centralized control through the telecommunication network.- Main function - ・Forecast of renewable generation and demand
・Charge/discharge control
・Mitigation control of short and long term fluctuation
・Diesel power generation control
Demand and supply control system- EMS(Energy Management System) Network -
Power Managementoffice
Control Center
Network
Wind power generation
(new)
PrefecturalOhmineyamawind powergeneration
EMS(terminal)
EMS(terminal)
EMS(terminal)
EMS(main)
Saigo power station
Kuroki power station
Nishinoshimasubstation
Control system
StorageBatteries Photo voltaic
generation(new)
:Tie line:EMS information:Control system information
Legend
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By means of unmanned automatic operation, coordinated control between storage battery and internal-combustion power is executed.
EMS operation control mechanism
Long term controlShort term control
Renewable generation forecasting
Supply and demand plan(long-term control)
Demand forecast
Li-ion batteryInternal
combustionNAS Battery
・Weather Forecast Data・Historical Data
EMS
⊿P+⊿f Control
Internal combustion output
Frequency
Allocation of control demand
The short-term control demand
Command the number of operating units and the output
Feedback control
Economical load dispatchingor Priority List Method
Supply and demand control(middle-term control)
17Operational performance of the storage battery
Currently, coordinated control performance is generally satisfactory.
(MW)
(Hz)
Example of Coordinated control performance (April 26, 2016)
Total output of Renewable energy
Total output of Internal-combustion
Total demand
NAS battery output
Frequency management value (upper limit)
Frequency management value (lower limit)
Frequency
Lithium ion battery output
Lithium ion batteryAbsorb small fluctuation
NAS batteryDischarge the surplus power during the daytime to peak load
0
60
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4.Effect and future prospects by the demonstration project
19Expected benefits
②Reduction of environmental impact
By reducing fossil fuel diesel power generation consumption, We can reduce CO2 emissions
③Activation of the local community
Hybrid storage battery is the first challenge in Japan.
Expect an increase of visitors
④Development and application of new technology
Accumulate technical knowledge such as the EMS control logic
Contribute to the solution of global challenges
①Improvement of the power supply stability
Introduction of renewable energy and storage battery system improves the stability of power supply in isolated power system
Verification being continued aiming further penetration of renewables
About 10 thousand tons CO2 reduction per year
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Acknowledgements
This project was realized with great support of the Ministry of the Environment, through the adoption of the “Storage battery demonstration project for promoting the introduction of renewable energy for remote islands“, subsidized by the ministry.
Also, we have received great cooperation from each municipals of Nishinoshima Town, Oki-Islands, and Shimane Prefecture, in the process of the construction of the substation, and the introduction of renewable energy.
We would like to express our sincere appreciation for the efforts of those concerned.
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Nakanoshima (Ama)Nishinoshima (Nishinoshima)
chiburijima (Chibu) Dogo (Okinoshima)
<Demonstration project website (Oki hybrid Daisakusen )>http://www.energia.co.jp/okihybrid/index.html