Transcript Slide 1

Transmission and Wind
Integration
June 7, 2010
Michael Goggin
American Wind Energy Association
Outline
● Benefits of Wind Energy
● Transmission Overview
● Wind Integration Overview
Currently Installed MW by State
Over 500,000 Total
Jobs Supported By
Wind In DOE report
Fact: in 2008,
35,000 new jobs
added
DOE 20% Report Scenario: 46 States Could
Have Major Wind Development by 2030
DOE 20% Report Summary: Costs & Benefits
Incremental direct cost to society
$43 billion
50 cents/month/
household
Reduction in emissions of greenhouse gasses and
avoided carbon regulation costs
825 million tons of
CO2
$50 to $145 billion
Reduction in water consumption
8% through 2030
17% in 2030
Jobs supported and other economic benefits
500,000 total with
150,000 direct jobs
$2 billion in local
annual revenues
Reduction in nationwide natural gas use and
savings for all gas consumers
11%
$86-214 billion
Sources: DOE, 2008 and Hand et al., 2008
Note: All dollar values are in NPV
Transmission
The Lack of Transmission is a Major Problem
● How a Lack of Transmission Hurts Renewables:
• Renewable projects cannot connect to the grid
• Project output can be curtailed because of inadequate
transmission
• Cannot capture benefits of geographically diverse
resources
● Transmission Needed Anyway to Reduce Congestion and
Improve Reliability
• Consumers losing $10s of billions per year due to
transmission congestion and inefficiency
• Reliability events cost consumers billions per year
• Nearly every source of new generation will need new
transmission
Wind in Interconnection Queues by State
Washington
8,702
Oregon
14,336
Montana
5,694
Idaho
730
Wyoming
9,582
Nevada
4,099
North
Dakota
12,602
South
Dakota
27,806
Nebraska
2,690
Utah
1,349
California
11,575
3,994
Colorado
15,904
New Mexico
18,007
Kansas
9,433
Minnesota
18,203
Wisconsin
628
Iowa
17,639
Maine
1,866
NH
496
Michigan
3,242
New York
6,990
Penn.
Indiana
2,935
Ohio
8,225
3,810
Illinois
WV
17,086
818 VA
83
Missouri
5,411
Oklahoma
10,187
Arkansas
60
Texas
50,669
VT
236
RI
949
MA
520
NJ
704
DE
450
MD
100
Under 1000 MW
1,000 MW-8,000
MW
Over 8,000 MW
Total 297,808 MW
AWEA calculation as of
March 16, 2010
Economies of Scale for
High-Capacity Transmission
Source:
MISO
Reduced Land Use
765-kV benefits are substantial over 500-kV and 345-kV.
Description
765
500
345
345
Circuits/Tower
1
1
1
2
Conductors/Phase
6
3
2
2
SIL per Line (MW)
2400
910
400
800
Lines Required for
2400 MW Capacity
1
3
6
3
ROW per line (ft)
200
200
150
150
Total ROW (ft)
200
600
900
450
ROW utilization
factor
100%
38%
22%
44%
Typical Height (ft)
132
124
110
172
*Cost/Mile ($M) for
2400 MW capacity
2.6
6.9
6.6
4.5
Costinin2006
2007$US,
$US,
based
average
terrain.
•*•* Cost
based
onon
average
terrain
•**
capacity
measure,
thermal
capacity
is
•** SIL
SILisisa arelative
relative
capacity
measure,
thermal
capacity
~4000
MW
for 765
2000
for 500
kVfor 500 kV.
is over
4000
MWkV
forand
765~kV
andMW
~ 2000
MW
•
Source: AEP
•
Transmission voltage selection significantly affects
performance, cost and the environment.
The Market Failures
● Economic benefits of transmission do outweigh costs:
• Joint Coordinated System Plan: Would pay for itself
in 7 years by reducing power prices
• Texas study: Would pay for itself in 3 years
• Reliability benefits
• Reduction in fuel price volatility impacts
• Benefits of connected renewables: environmental,
economic development, energy security
● Why don’t we just build the transmission?
- Obsolete transmission policies, particularly cost
allocation policies
- In many regions, current cost allocation policy is
analogous to charging the next truck entering a
congested highway the full cost of adding a new lane
Policy Reform Needed: The Three P’s
● Policy reforms needed to allow new
transmission construction to proceed:
• Planning (pro-active planning)
• Paying (broad regional cost allocation)
• Permitting (streamlined siting)
● AWEA-SEIA white paper at
http://www.awea.org/GreenPowerSuperhighways.
pdf
Wind Integration
2009 U.S. Wind Penetration
Source: AWEA data, EIA forms 906 and 920, 2008 data
European Wind Energy Penetration, 2008
UK
1.82%
Austria
3.28%
Netherlands
3.40%
Greece
3.67%
EU-27
3.78%
EU-25
3.89%
EU-15
4.28%
7.00%
Germany
8.42%
Ireland
Portugal
9.26%
11.76%
Spain
Denmark
0.00%
21.22%
5.00%
Source: EWEA 2007 and Eurelectic 2006
10.00%
15.00%
20.00%
25.00%
Power System Operations:
Background
● Electricity supply and demand must match at all
times
● Grid operators accomplish this by increasing and
decreasing the output of flexible generators, like
hydroelectric and natural gas power plants
● Electricity demand is highly variable; forecasts are
used, but there is still variability and uncertainty
● Electricity supply is also variable and uncertain
● As a result, grid operators hold generation in reserve
to accommodate aggregate variability:
• Regulation reserves
• Load-following reserves
• Contingency reserves
● Reserves can be spinning or non-spinning
The Flexibility Supply Curve
Source: NREL
The Distance Element
of Wind’s Variability
Correlation in plant output as a function of time and distance
Source: NREL
The Time Element
of Wind’s Variability
Wind Penetration
1 minute 5 minute 1 hour
Study
Texas 2008[1]
15,000 MW
6.5 MW
30 MW
328
MW
California
Energy
Commission
2007[2]
2,100 MW, +330MW solar
0.1 MW
0.3 MW
15 MW
7,500 MW, +1,900 MW
solar
1.6 MW
7 MW
48 MW
12,500 MW, +2,600 MW
solar
3.3 MW
14.2 MW
129
MW
--
1.8 MW
52 MW
New York
2005[3]
3,300 MW
[1]
http://www.uwig.org/Wind_Generation_Impact_on_Ancillary_Services_-_GE_Study.zip
http://www.uwig.org/CEC-500-2007-081-APB.pdf
[3] http://www.uwig.org/nyserdaphase2appendices.pdf
[2]
Wind Integration Costs
Date
Study
Wind
Capacity
Penetratio
n (%)
Regulation
Cost
($/MWh)
Load
Following
Cost
($/MWh)
Unit
Commitmen
t Cost
($/MWh)
Gas
Supply
Cost
($/MWh)
Total
Operating
Cost
Impact
($/MWh)
May ‘03
Xcel-UWIG
3.5
0
0.41
1.44
na
1.85
Sep ‘04
Xcel-MNDOC
15
0.23
na
4.37
na
4.60
June ‘06
CA RPS
4
0.45*
trace
na
na
0.45
Feb ‘07
GE/Pier/CAIAP
20
0-0.69
trace
na***
na
0-0.69***
June ‘03
We Energies
4
1.12
0.09
0.69
na
1.90
June ‘03
We Energies
29
1.02
0.15
1.75
na
2.92
2005
PacifiCorp
20
0
1.6
3.0
na
4.60
April ‘06
Xcel-PSCo
10
0.20
na
2.26
1.26
3.72
April ‘06
Xcel-PSCo
15
0.20
na
3.32
1.45
4.97
Dec ’08
Xcel-PSCo
20
3.95
1.18
5.136.30****
Dec ‘06
MN 20%
31**
Jul ‘07
APS
14.8
4.41**
0.37
2.65
1.06
Source: NREL
na
4.08
Lessons Learned from Wind Integration Studies
● Wind forecasting can significantly reduce integration costs by
reducing uncertainty
● Geographically diverse wind resources tend to be less variable
● Wind resources spread over larger areas are less variable –
one of the reasons why transmission is important
● Diverse wind has very little variability on the minute-to-minute
time scale
● Wind is easier to integrate on more flexible power systems
● Market/system operation reforms can significantly reduce wind
integration costs
● A robust transmission grid can significantly reduce integration
costs
● Integrating wind is a cost issue, not a reliability issue (thinking
about “limits” or renewable thresholds is inaccurate)
● Storage is not needed, but can help
Solutions: Transmission is Critical
● NERC IVGTF: “Transmission expansion, including
greater connectivity between balancing areas, and
coordination on a broader regional basis, is a tool
which can aggregate variable generators leading
to the reduction of overall variability. Sufficient
transmission capacity serves to blend and smooth
the output of individual variable and conventional
generation plants across a broader geographical
region. Large balancing areas or participation in
wider-area balancing management may be needed
to enable high levels of variable resources.” (p. 43)
Shorten Power Plant Dispatch Intervals
• NERC: “More frequent and shorter scheduling intervals for
energy transactions may assist in the large-scale integration
of variable generation.” (p. 61)
• In much of the U.S., power plants are scheduled to operate
for hourly intervals, and expensive reserves are used to
accommodate intra-hour variability
• Using 5- or 10-minute scheduling intervals accommodates
intra-hour variability without reserves
• Studies show significant savings from moving to 5- or 10minute intervals instead of hourly:
• Bonneville Power: 80% reduction in wind integration
costs
• Avista: 40-60% reduction in wind integration costs
Flexibility through markets
● NERC: “Additional sources of system flexibility include
the operation of structured markets, shorter scheduling
intervals, demand-side management, reservoir hydro
systems, gas storage and energy storage.” (p. 48)
● Ancillary services markets provide incentives for
generators, demand response, and other flexible
resources to offer their services to the grid
● Markets ensure that lowest-cost resources provide
needed flexibility services
Larger Balancing Areas
• Allow excess power in one region to be shared with
neighboring regions
• Enable diverse wind resources spread over a larger area to
be connected to the same grid, canceling out their
variability
• Create cost savings
• Midwest ISO estimates savings from consolidating its 26
balancing areas into one are 3.7 to 6.7 times greater than the
costs
• Savings are large even on power systems without wind
energy
• Consolidation can be done physically or virtually
Grid Balkanization Impairs Wind Integration
Improve Use of Wind Forecasting
• NERC: “Forecasting is one of the key tools needed to
increase the operator’s awareness of wind plant output
uncertainty and assist the operator in managing this
uncertainty.” (p. 55)
• Largest opportunities for
improvement:
• Better integrating forecasts
into power system
operations
• Faster updating short-term
models, more data
Questions?
Michael Goggin
[email protected]
202-383-2531