ETAAC
Energy Sector
Energy Storage------------------------
Smart Grid
July 12, 2007San Francisco, CA
2
Energy Storage• Electric energy storage goal of the industry
• Cost-effective energy storage would benefit all areas of the energy value chain: generation, transmission, distribution, and end-use
• Key applications: firming large penetration of intermittent renewables, grid support, end-use load shifting, etc.
• Current energy storage systems are only marginally cost competitive. Costs need to come down by factor of 2-5 times.
• Need innovation and standardization as well as policy recognition.
• California is best market for accelerating storage use due to technology base, clean energy emphasis (especially intermittent renewables), and leading-edge policies.
3
Energy Storage Technologies
• Many different energy storage technologies are available for use in storage for renewable integration applications
Pumped Hydro Compressed Air Energy
Storage Lead-acid batteries Nickel-cadmium batteries
• Each technology has advantages and disadvantages• Not all of these technologies are appropriate for all
applications
Lithium ion batteries Sodium-Sulfur Batteries Flow Batteries Flywheels Ultracapacitors
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Uses of Energy Storage
5
Balancing Function - Area Control
Hour Ahead Schedule
Incremental Energy
Decremental Energy
Day Ahead Schedule
Real Time Load
MW
Time
Real-Time Economic DispatchEvery 5 minutes
Upward Regulation
Ancillary Services• Regulation • Spinning Reserve • Non-Spinning
Reserve • Replacement
Reserve • Voltage Support• Black Start
capability
Ancillary Services• Regulation • Spinning Reserve • Non-Spinning
Reserve • Replacement
Reserve • Voltage Support• Black Start
capability
Downward Regulation
6
Loads & Resources
Source: CEC PIER-funded study by GE Energy, July 2006
Temporal Pattern: July 2003 Average DayTemporal Pattern: July 2003 Average Day
7
July 2006 Heat Wave – Peak Hours Wind Generation Energy Production
July 17:
(2:41 pm) 46,561 MW
July 21:
(4:28 pm) 49,036 MW
July 24:
(2:44 pm) 50,270 MW
New Records
Record
Time of Record Peaks
x
xx
Source: CAISO
Planned Capacity Level
8
Need to Shift Some Wind Energy Production from Off-Peak to On-Peak
January 6, 2005 California Wind Generation
0
50
100
150
200
250
300
350
400
12:0
0 A
M
1:00
AM
2:00
AM
3:00
AM
4:00
AM
5:00
AM
6:00
AM
7:00
AM
8:00
AM
9:00
AM
10:0
0 A
M
11:0
0 A
M
12:0
0 P
M
1:00
PM
2:00
PM
3:00
PM
4:00
PM
5:00
PM
6:00
PM
7:00
PM
8:00
PM
9:00
PM
10:0
0 P
M
11:0
0 P
M
MW
TOTAL Pacheco Solano Tehachapi Altamont San Gorgonio
Maximum Energy Production at night
9
Potential use of Flywheel Energy Storage for Area Control Error and Frequency Control
June 4, 2004
59.75
59.8
59.85
59.9
59.95
60
60.05
60.1
0:00
0:40
1:20
2:00
2:40
3:20
4:00
4:40
5:20
6:00
6:40
7:20
8:00
8:40
9:20
10:00
10:40
11:20
12:00
12:40
13:20
14:00
14:40
15:20
16:00
16:40
17:20
18:00
18:40
19:20
20:00
20:40
21:20
22:00
22:40
23:20 0:
00
Fre
qu
ency
-
Her
tz
-1500
-1000
-500
0
500
1000
1500
AC
E M
egaw
atts
Freq ACE
10
20
25
30
35
40
45
1 2 3 4 5 6 7 8 9 10 11 12 1 2 3 4 5 6 7 8 9 10 11 12
Sys
tem
Lo
ad (
GW
)
Typical Load
Load w/ 4 mil. PHEVs
Off-peak load
Off-peak load
Vehicle-to-grid energy
(V2G)
Vehicle-to-grid energy
(V2G)
Ancillary Services available when vehicles are parked
Ancillary Services available when vehicles are parked
AM PM
Plug Hybrid Electric Vehicles Complement Renewables
off-peak load off-peak load
11
Dispatchability Option via Thermal Storage
Actual June dayActual June day
Actual September dayActual September day
Actual September day w/ supplemental gasActual September day w/ supplemental gas
Parabolic Trough Solar Technology for Utility Power Markets in the Southwestern United States, Henry Price, National Renewable Energy Laboratory, August 2004Parabolic Trough Solar Technology for Utility Power Markets in the Southwestern United States, Henry Price, National Renewable Energy Laboratory, August 2004
Solar thermal can add storage or to become more dispatchable.
12
13
14
Next Gen
Li-ion?
Next Gen Flow
Battery?
15
16
17
18
Compressed Air Energy Storage (CAES)
19
CAES Geology by State
20
Lithium Ion Battery