Transcript Slide 1
Energy Storage Technologies
for Utility Applications
GRIDSCHOOL 2010
MARCH 8-12, 2010 RICHMOND, VIRGINIA
INSTITUTE OF PUBLIC UTILITIES
ARGONNE NATIONAL LABORATORY
Vladimir Koritarov
Center for Energy, Economic, and Environmental Systems Analysis
Decision and Information Sciences Division
ARGONNE NATIONAL LABORATORY
[email protected] 630.252.6711
Do not cite or distribute without permission
MICHIGAN STATE UNIVERSITY
With the Advance of Renewable Energy Sources,
Energy Storage Is Becoming Increasingly Important
Energy storage is not a new concept for electric utilities
Although extremely desirable, wider deployment of energy storage
has been limited by the economics/costs and available locations
Pumped-storage hydro, large hydro reservoirs, and a few pilot CAES
plants were the only way to store energy
Small quantities of electricity were also possible to store in batteries
and capacitors
Large-scale implementation of energy storage (both system and
distributed) is considered to be the key for enabling higher
penetration (>20%) of renewable and variable generation sources,
such as wind and solar
Energy storage is also expected to contribute to more efficient and
reliable grid operation, as well as to reduced emissions from the
power sector
GridSchool 2010
Koritarov - 02
There are a Variety of Energy Storage Applications
System storage (e.g., pumped-storage
plants, CAES, large-scale battery storage
Currently 22 GW of pumped-storage in
the U.S.
Renewable energy support (e.g., energy
storage combined with wind plant, etc.)
Distributed energy storage (demand-side
storage, customer installations, PHEV &
EV batteries, etc.)
GridSchool 2010
Koritarov - 03
A Number of Energy Storage Technologies Are Being
Developed
Lead-acid (L/A) batteries
Flooded L/A batteries
Valve-regulated lead-acid (VRLA) batteries
Sodium-sulfur (NaS) batteries
Flow batteries
Sodium bromide sodium polysulfide
Zinc bromine (Zn/Br)
Vanadium-redox (V-redox)
Nickel cadmium (Ni/Cd) batteries
Lithium-ion (Li-ion) batteries
Compressed air energy storage (surface and underground)
Flywheels
Super-capacitors
Superconducting magnetic energy storage (SMES)
Hydrogen storage
Concentrated solar with molten salt energy storage
GridSchool 2010
Koritarov - 04
Requirements for Energy Storage
Energy density
High power output
Cycle efficiency
Cycling capability
Operating lifetime
Capital cost
GridSchool 2010
Koritarov - 05
Cycle Efficiency of Energy Storage Technologies
GridSchool 2010
Koritarov - 06
Energy Storage Capital Costs Requirements
GridSchool 2010
Koritarov - 07
Size and Weight of Energy Storage
GridSchool 2010
Koritarov - 08
Energy Storage Can Provide Services at all Levels of the
Power System Value Chain
Electricity supply
Load shifting (load-leveling, time-shift, price
arbitrage)
Generation capacity
Ancillary services
Load following
Regulation service
Contingency reserve (spinning and supplemental)
Transmission stability support
Voltage support
Grid system reliability
Transmission congestion relief
T&D upgrade deferral
Substation backup power
GridSchool 2010
Koritarov - 09
Energy Storage Can Provide Services at all Levels of the
Power System Value Chain (cont’d)
Integration of renewable and variable energy
sources
Capacity firming
Renewable energy time-shift
Renewable energy integration (power quality,
ramping and load following)
Utility customer
Time-of-use energy cost management
Capacity charge management
Improved power quality and reliability
Environmental benefits
Reduced fossil fuel consumption
Reduced environmental emissions
GridSchool 2010
Koritarov - 010
Operating Characteristics of Energy Storage Technologies
Determine their Suitability for Different Applications
Flywheels, super-capacitors, SMES, and other
storage technologies with the short-term power
output (minute time scale)
Regulation service
Spinning reserve, etc.
NaS batteries, flow batteries, hydrogen fuel
cells, CAES, pumped storage can provide
several hours of full capacity:
Load shifting
Electricity generation
T&D deferral, etc.
GridSchool 2010
Koritarov - 011
Energy Storage Requirements for Utility Applications
GridSchool 2010
Koritarov - 012
Operation of Storage Driven by Supply/Demand Balance,
Ancillary Services Requirements, and Market Values
Short-term storage (seconds to minutes)
For services such as frequency regulation, reactive power supply and
voltage support
• Requires fast/secure communications for automatic control
For contingency reserves (e.g., spinning reserve)
• Requires communication to verify the requirement to operate and to
confirm the available capacity
Longer term storage (minutes to hours)
Energy/price arbitrage, load following and ramping
Scheduling of charging and discharging requires information on current
value of energy and the expected future value of energy (may include
value of capacity and energy)
Information on constraints on total capacity, ramping, and total energy
limits of the storage system
GridSchool 2010
Koritarov - 013
Typical Operation of Pumped-Storage Hydro Plant for
Energy/Price Arbitrage
200
100
180
90
160
80
140
70
120
60
100
50
80
40
60
30
40
20
20
10
0
0
Monday
Tuesday
Wednesday
Production
GridSchool 2010
Thursday
Friday
Pumping
Saturday
€ / MWh
MW
Aguieira - Week 39 2007
Sunday
Projected Prices
Koritarov - 014
The Case for Storage: Price Arbitrage in the Midwest
140
140
Wisconsin
Average Peak/Off-Peak Price Spreads [$/MWh]
Average Peak/Off-Peak Price Spreads [$/MWh]
Manitoba
120
120
100
100
80
60
40
Average Peak/Off-Peak Price Spreads [$/MWh]
140
20
Jan-08 Feb-08 Mar-08 Apr-08 May-08 Jun-08
60
40
20
July 2008
120
0
80
0
Jan-08 Feb-08 Mar-08 Apr-08 May-08 Jun-08
Jul-08 Aug-08 Sep-08 Oct-08 Nov-08 Dec-08 Jan-09 Feb-09 Mar-09 Apr-09 May-09
Jul-08 Aug-08 Sep-08 Oct-08 Nov-08 Dec-08 Jan-09 Feb-09 Mar-09 Apr-09 May-09
100
GridSchool 2010
80
60
40
20
0
WI
MI
IL
MN
IA
OH
MO
IN
ND
MB
Koritarov - 015
How May Wind Affect Prices and Price Spreads:
Real-Time Prices in Illinois (ComEd) Hub in 2008
Over 300 hours (3.4%) with negative prices
Over 650 hours (7.5%) with prices below $10/MWh
500
500
Illinois Hub (ComEd) Real-Time Prices 2008
Illinois Hub (ComEd) Price Curve 2008
300
300
200
100
0
0
730 1460 2190 2920 3650 4380 5110 5840 6570 7300 8030 8760
Real Time Price [$/MWh]
400
Real Time Price [$/MWh]
400
200
100
0
0.0
-100
-100
-200
-200
-300
-300
GridSchool 2010
0.1
0.2
0.3
0.3
0.4
0.5
0.6
0.7
0.8
0.8
0.9
Koritarov - 016
1.0
How May Wind Affect Prices and Price Spreads
MISO-Minnesota Hub, 5/11-5/17/2009
250
4,000
90
3,500
200
3,500
60
3,000
150
3,000
30
2,500
100
2,500
50
2,000
0
1,500
0
2,000
1
2
3
4
5
6
7
8
9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
-30
1,500
Wind Power [MW]
Price [$/MWh]
4,000
Price [$/MWh]
120
0
-60
1,000
-90
500
-100
0
-150
-120
Real-Time Price
GridSchool 2010
Day-Ahead Price
Wind power
24
48
72
96
120
144
-50
168
1,000
500
Real Time price
Day Ahead price
Wind power
0
Koritarov - 017
Wind Power [MW]
MISO-Minnesota Hub, 5/13/2009
The Case for Storage: Advanced Wind Forecasting to
Reduce Uncertainty, Storage to Manage Variability
Current forecast tools do reasonably well
Mean absolute error is low (9.3%)
Forecasting ramps still an issue
Source: Iberdrola, 2009
GridSchool 2010
Koritarov - 018
The Case for Storage: Advanced Wind Forecasting to Reduce
Uncertainty, Storage to Manage Variability (& Reduce Curtailments)
Source: ERCOT, 2009
With limited or no wind forecasting, and constraints in the system, wind
curtailments may occur; strategically located storage could alleviate the situation
GridSchool 2010
Koritarov - 01919
Coordinated Operations of Wind with (Hydro) Storage May
Reduce Wind Curtailments in Congested Areas (up to 75%)
35%
30%
25%
20%
15%
10%
5%
0%
SINTEF
KTH (exjobb)
Skelleftekraft
KTH (coord.
algorithm)
Curtailments without coordination in % of unconstrained production
Curtailments with coordination in % of unconstrained production
Source: Matevosyan, 2008
GridSchool 2010
Koritarov - 020
Without Energy Storage, Large Wind Integration
Poses a Challenge to Electric Power Systems
Utility systems can relatively easily
absorb small penetration of wind
energy (<10-15%)
Higher wind energy penetration
(>20%) presents a challenge
Wind energy production in Denmark
in 2008 amounted to 19% of the total
electricity generation
German utility E.ON: “The more wind
power capacity is on the grid, the
lower the percentage of traditional
generation it can replace.”
Firm capacity from wind in 2007:
about 7% of installed capacity
Firm capacity in 2020 is expected
to drop to 4%.
GridSchool 2010
Source: E.ON Wind Report 2005
Koritarov - 021
The Case for Storage: Example of On-Site Wind Farm
Storage Operations Driven by Economics
Off-Peak
Off-Peak
Peak Period
GridSchool 2010
Peak Period
Source: Faias et al, 2008 Koritarov - 022
Large Wind Integration Will Require Significant Use
of Energy Storage
Energy storage coupled with wind farms
would provide for:
Firming of wind capacity
Time-shifting of electricity generation
Reduced need for backup capacity
Reduced ramping or conventional units
Lower reserve requirements
Questions:
What is the optimal amount of storage?
What type of storage is best for use
with wind farms?
Similar issues exist for solar and other
variable energy resources
GridSchool 2010
Source: E.ON Wind Report 2005
Koritarov - 023
The Case for Storage: Example of On-Site Wind Farm
Storage Operations Driven by Economics
Source: Faias et al, 2008
GridSchool 2010
Koritarov - 024
Plug-in Hybrid and Battery Electric Vehicles: A Challenge
or an Asset?
GridSchool 2010
180,000
30,000
WECC April 2020 Aggressive PHEV Case:
Charge When Arriving @ Home
150,000
PHEV Aggressive
Baseload
25,000
Base + PHEV Aggressive
20,000
Total Load [MW]
PHEV Load [MW]
120,000
90,000
15,000
60,000
10,000
30,000
5,000
0
0
0
24
48
72
96
120
144
168
180,000
30,000
WECC April 2020 Aggressive PHEV Case:
Smart Charging
150,000
25,000
PHEV Aggressive Smart
Baseload
Base + PHEV Aggressive Smart
20,000
PHEV Load [MW]
120,000
Total Load [MW]
Impacts to the electric grid, especially to
the distribution system (e.g.,
transformers)
Charging patterns and behavior
Vehicle to grid (V2G) services:
Contingency reserve
Frequency regulation
Dispersed energy storage
Vehicle to home (V2H) services
Backup power
Demand response (load shifting)
Storage for distributed renewable
sources
Impacts on electricity prices
Impacts on emissions
90,000
15,000
60,000
10,000
30,000
5,000
Koritarov - 0025
0
0
24
48
72
96
120
144
168
In Conclusion, Energy Storage is the Key for Large-Scale
Integration of Renewable and other Variable Sources
Energy storage provides opportunity for price arbitrage
Arbitrage opportunities vary by region and season
Are current price spreads sufficient to justify investment at current costs?
What are the trends in price spreads and storage costs?
Energy storage can provide ancillary services
With large ramp-up in wind, the need for regulation and spinning reserve
will increase
The importance of storage, both system and distributed, will also increase
GridSchool 2010
Koritarov - 026