Transcript PowerPoint File

Demonstrating the benefits of
energy storage on an 11 kV
Distribution Network
Matthieu Michel –
Technology Innovation and Co-ordination Manager
 2012. UK Power Networks. All rights reserved
Project Objectives:
•
Validate the capabilities of a Li-ion Energy Storage System (ESS)
•
Demonstrate load-shifting and other interventions within the limits of the device
200 kW, 1 hour discharge duration
600 kW, short durations
Power rating
Duration
Real power
Reactive power
Finite (nom 200 kW)
Finite (nom 600 kVAr)
Finite (nom 1hr)
Unlimited
•
Evaluate the network benefits: accommodate additional demand and generation
•
Understand the potential lifetime of the device
•
Presentation:
Early results from Operation of the device
Key considerations: Efficiency, Losses, cost of energy
 2012. UK Power Networks. All rights reserved
Progress Highlights:
•
The storage device has operated as a STATCOM since commissioning (April 2011)
•
Exchanges of real power have started (May 2012)
•
Network diagram
Wind farm
(10 turbines)
2.25MW
Hemsby
(Energy
Storage
System)
Martham
Primary
Site where
Additional
monitoring is
being installed
Ormesby
Primary
 2012. UK Power Networks. All rights reserved
11.1
High Voltage event caused by
windfarm output triggering ESS to
import reactive power
11.07
10.85
1
11
0.8
Voltage (kV)
D
E
A
D
B
A
N
D
1.2
10.9
10.8
0.6
Increase in windfarm
output resulting in
voltage increase
0.4
Low Voltage
triggering ESS
to export
reactive power
0.2
10.7
0
-0.2
10.6
18-Apr-11
18/04
ESS Volts (kV) [Model]
19/04
19-Apr-11
20-Apr-11
20/04
Windfarm (MW)
ESS_Q (MVAr) [Data] Windfarm
ESS Reactive
Output
Power
ESS Volts (kV) [Model]
 2012. UK Power Networks. All rights reserved
21-Apr-11
Reactive Power (MVAr) / Windfarm output (MW)
Operation: STATCOM
Voltage at Hemsby
without ESS
(simulated data)
Voltage at Hemsby
with ESS (Simulated
using real data)
Operation: STATCOM Settings Change - July 2012
•
Tightened under and over voltage targets from 10.96kV ± 0.11kV, to ±0.08kV
•
kVAr exchanged with the network (Number of occurrences) / Voltage band
Week 1
BEFORE SETTING
CHANGES
AFTER SETTING
CHANGES
10.96kV ± 0.11kV
10.96kV ± 0.08kV
Week 2
Week 3
Week 4
 2012. UK Power Networks. All rights reserved
Week 5
Week 6
Week 7
Week 8
Operation: Real Power Exchanges - May 2012
Demand increase
due to evening
peak
Drop in demand
due to export
from ESS
Fluctuations due
to Windfarm
output or
variation in
demand
 2012. UK Power Networks. All rights reserved
Increase in
demand due to
switching from
Export to Import
Considerations: Round Trip Efficiency and Losses
•
The overall round trip efficiency of the installation is quoted to be more than 90%
•
Several components will
impact the efficiency and
48 kW
losses
AUXILIARIES
1MVA STEP UP
TRANSFORMER
(2.2kV to 11kV)
AND CIRCUIT
BREAKER
•
49.7 kW delivered by batteries
Li-ION BATTERIES
48 kW delivered to network
49.7 kW
•
SVC Light
POWER
CONVERSI
ON SYSTEM
(DC to AC)
50kW discharge scenario:
Each component is being
assessed individually
 2012. UK Power Networks. All rights reserved
Considerations: Energy cost and Battery life
Financial impact of an example daily operation:
2 full charges / discharges @ 100kW
£90
Hemsby import
charge
•
Import chage / Export revenue (£)
£80
Export
revenue
(80%
System
Sell price)
£70
£60
£50
£40
On the current Hemsby tariff
Energy import charges will be higher than
the revenue that can be generated from
Import charge
exporting
Export
revenue
£30
a similar amount of energy
£20
£10
£0
Scenario
1: Optimised charge /
Optimised
discharge time
•
Scenario
2: Example
of a worst
Worst
case
case charge / discharge time
Battery life will depend on:
Number of cycles
Depth of discharges
•
1 x daily cycle @ 80% depth of discharge: 10 years
1 x daily cycle @ 40% depth of discharge: 20 years
•
40% / 10,000 Cycles
The impact of each mode of operation on the
battery life will be considered
 2012. UK Power Networks. All rights reserved
80% / 3,000 Cycles
Next steps: Device Operations
Control mode 4:
Algorithmic control
based on real time network
measurements and wind farm output
Benefit demonstration
started
Benefit to be demonstrated
Management of Peak power flows
Control mode 3:
Remote
operations
Now
Management of voltages across
feeders
Reduce reverse power flows
Improve Power factor
Switching between feeders
Control mode 2:
On-site Manual
Combine Voltage stabilisation + Real power exchanges
Control mode 1:
Voltage stabilisation (different set points)
No intervention
Management of peak power flows – Time of day
Voltage stabilisation
Apr 11
May 12
July 12
 2012. UK Power Networks. All rights reserved
Jan 13
Oct 13
Conclusions:
•
The storage device is performing as expected: Reduce voltage fluctuations and manage
power flows
•
The early stages of the project have been challenging:
Energy contract, IT connections, troubleshooting issues following commissioning.
•
Submitted request for extension: October 2013
•
More work is to be done but there is learning to be shared: Early learning report published.
Copies available
at the UK Power Networks
stand
 2012. UK Power Networks. All rights reserved