Charging Ahead
Power Grid Perspectives on Plug-in Electric
Vehicles
1
ISO/RTO Council (IRC)
North America’s 10
independent system
operators (ISOs) and
regional transmission
organizations (RTOs)
serve two-thirds of
electricity consumers in
the United States and
more than 50 percent of
Canada's population.
2
IRC Electric Vehicle Study
 IRC report examines grid impacts of Plugin Electric Vehicles (PEVs). Among the
study’s conclusions:
• One million PEVs may be on U.S.
roadways in a decade -- with
concentrations of the vehicles in the
major metropolitan areas of the West
Coast and the Northeast.
• Staggered charging of PEVs would reduce
the potential negative impact on electric
load.
• Power companies will need new tools to
manage growth in PEV use.
3
PEV Projections – ISO/RTO
Of the 1,000,000 PEVs
expected over the next
10 years, more than
684,000 may be served
by U.S. ISO/RTOs
CAISO
267,654
ISO-NE
61,074
NYISO
43,738
PJM 144,172
ERCOT
42,769
SPP 30,459
Midwest ISO
94,644
4
The Historical Data: The Pace of
Prius Market Penetration
United States Annual Prius New
Registrations
Methodology question
–
Why focus on the Prius?
–
Prius was (a) high mileage, (b) very new
technology, (c) “green,” (d) relatively
expensive
Prius sales illustrate the introduction of a new
vehicle technology
–
–
Market introduction: first generation
technology, limited production
capacity, high prices
Market development: second
generation, improved technology,
expanded capacity, growing consumer
interest and acceptance
180,000
160,000
140,000
120,000
100,000
80,000
60,000
40,000
20,000
The Prius study period represents “early
adopters” only
–
–
Data focus on Prius concentrations, not
“niches” or very small numbers
NOT focused on distribution circuits –
but could be!
0
2000
2001
2002
2003
2004
2005
2006
2007
United States
Notes:
• 2000-2002 represented Prius “Gen 2”
• Prius “Gen 2” introduced in 2003
Note: All Prius data provided by R. L. Polk
What have we learned about
Prius early adopters?
New Prius Registrations – Total Prius Sales, 2000-2007*
Ranking by state
1 – 10
11 – 20
21 – 30
31 – 40
41 – 51
New Prius registrations for study period:
2007:
435,400
vehicles
*2000
Prius–data
provided
by R. L.
Polk
Buyer Demographics: Locations of
New Registrations
Sales of the Prius were generally concentrated in states with the
highest population – but…
States With Highest Population, 2000-2007
Rank
1
2
3
4
5
6
7
8
9
10
State
CA
TX
NY
FL
IL
PA
OH
MI
GA
NC
Population
(Millions)
36.8
24.3
19.5
18.3
12.9
12.5
11.5
10.0
9.7
9.2
States With Highest Prius Sales
Rank
1
2
3
4
5
6
7
8
9
10
State
CA
FL
TX
NY
VA
WA
PA
IL
MA
MD
Total New
Registrations
123,989
20,596
18,297
18,033
17,828
16,459
14,791
14,660
13,723
12,040
What have we learned about early
Prius consumers?
Prius Registrations – New Regi
strations Per Capita, 2000-2007*
Ranking by state
Per capita data
New Prius registrations for study period:
2000 – 2007: 435,400 vehicles
* Prius data provided by R. L. Polk
Rank
Registrations
per 1,000
1 – 10
2.0 – 3.4
11 – 20
1.3 – 1.9
21 – 30
1,0 – 1,3
31 – 40
0.7 – 1.0
41 – 51
0.3 – 0.7
Buyer Demographics: Urban
Concentrations
…but the demographics of the Prius customer has a strong “coastal” character
- and was heavily concentrated in the largest urban areas, which account for
31.6% of total U.S. sales
States Where Prius Was Most Popular
Rank
1
2
3
4
5
6
7
8
9
10
State
CA
VT
OR
NH
WA
DC
VA
MD
MA
ME
Registrations per
1000 Residents
3.37
3.21
3.04
2.54
2.51
2.46
2.29
2.14
2.11
2.03
Note:
“Most popular” = highest per capita sales
Metro Areas Where Prius Was Most Popular
Rank
1
2
3
4
5
6
7
8
9
10
Metro Area
New York
Los Angeles
Chicago
Wash., DC
San Francisco
Philadelphia
Boston
Detroit
Dallas
Houston
Total New
Registrations
18,622
52,700
9,400
15,100
42,900
6,300
13,200
3,000
3,200
3,900
% of
US
3.7%
10.4%
1.9%
8.4%
8.4%
1.2%
2.6%
0.6%
0.6%
0.8%
The “Take-aways” From the
Prius Review
1.
Early adopters WERE NOT proportional to population size alone
–
–
2.
3.
Significant differences in per capita sales between states and regions
Some strong preferences, some distinct disinterest
TOTAL numbers WERE driven by overall population size
The “Coastal” phenomenon for this class of vehicle among early
adopters is very clear – in both the per capita numbers and in the overall
sales numbers
Conclusions
1.
Early adopters have a clear demographic locational component
•
2.
The so-called “coastal effect” appears valid
There are likely to be significant differences in PEV clustering among
ISOs/RTOs
•
BUT – from an ISO/RTO perspective, where clusters of significant size are needed
to provide a useful level of MWs of connected PEVs, POPULATION SIZE matters
more than almost any other criteria
III PEV Projections: Distribution
Where are PEVs likely to be concentrated among the ISOs
and RTOs?
PEVs: Where will they land?
• How do we apply the Prius experience to project the distribution of PEVs
among the ISOs and RTOs?
– Where are PEVs likely to be concentrated in significant numbers from
an ISO/RTO perspective?
• Key to an ISO/RTO perspective
– MWs – concentrations of PEVs that provide significant MW demand
response resources
• One vehicle here and there doesn’t count
• Where will PEVs wind up?
– The consumer model: PHEVs and EREVs (and some BEVs)
• The Prius analogy – applied to consumer behavior, not fleets
– The “fleet” model: BEVs
• An “urban center” model, driven largely by population size
The “Top Twenty” Metropolitan
Areas
City
Population
City
Population
New York
16,400,000
Atlanta
4,100,000
Los Angeles
16,400,000
Miami
3,900,000
Chicago
9,200,000
Seattle-Tacoma
3,600,000
Washington, DC
7,600,000
Phoenix
3,300,000
San Francisco
7,000,000
Minneapolis
3,000,000
Philadelphia
6,200,000
Cleveland-Akron
3,000,000
Boston
5,800,000
San Diego
2,850,000
Detroit-Ann Arbor
5,500,000
St. Louis
2,600,000
Dallas-Fort Worth
5,200,000
Denver-Boulder
2,600,000
Houston
4,700,000
Tampa-St. Pete
2,400,000
Metro areas located within the ISO/RTO study area are in bold, other metro areas are in gray
PEVs in the “Top Twenty”
Metropolitan Areas – Slide 1 of 2
City
New York
Consumer PEVs
Fleet PEVs
Total PEVs
40,000
14,069
54,069
105,000
14,069
119,069
Chicago
20,000
7,892
27,892
Washington, DC
31,000
6,520
37,520
San Francisco
85,000
6,005
91,005
Philadelphia
13,000
5,319
18,319
Boston
27,000
4,976
31,976
Detroit-Ann Arbor
6,000
4,718
10,718
Dallas-Fort Worth
6,500
4,461
10,961
Houston
8,000
4,032
12,032
Los Angeles
Metro areas located within the ISO/RTO study area are in bold, other metro areas are in gray
PEVs in the “Top Twenty”
Metropolitan Areas – Slide 2 of 2
City
Consumer PEVs
Fleet PEVs
Total PEVs
Atlanta
4,500
3,517
8,017
Miami
8,000
3,346
11,346
Seattle-Tacoma
23,000
3,088
26,088
Phoenix
13,000
2,831
15,831
Minneapolis
8,000
2,574
10,574
Cleveland-Akron
6,000
2,574
8,574
20,000
2,445
22,445
St. Louis
3,500
2,230
5,730
Denver-Boulder
9,000
2,230
11,230
Tampa-St. Pete
7,000
2,059
9,059
San Diego
Metro areas located within the ISO/RTO study area are in bold, other metro areas are in gray
IV Moving from PEVs to MWs
Translating from numbers of PEVs to numbers of MW in
ISO/RTO metro areas
MW: Translating PEVs to Available
MWs
It’s not the size, it’s the miles driven – and the kWh used – that matter
– PEVs come with different size batteries (e.g., 10 kW, 25 kW, 100 kW))
– PEVs come in different designs (e.g., PHEV, EREV, BEVs)
– The PEV may be hooked up, but it may be already fully charged and not
available for demand reduction
Ultimately, MW available for demand reduction are a function of:
– Number of PEVs of varying size available locally
– Charging voltage (e.g., Level 1, 2, 3) – how long it takes to charge
– Connection at load
• Likelihood that a vehicle is in fact connected at a given moment in time
• Likely depth of discharge at time of hook-up
• BOTH are stochastic
Calculating “Available” MW
Implications
– Our analysis estimates the number of PEVs in the SMSA clusters
– We estimate a split between PHEVs, EREVs and BEVs, and locate the majority
of BEVs in the larger urban centers
• 80% in the “top 20”
– To arrive at MW estimates it is necessary to “rerate” the kW of the batteries to
recognize:
• Some batteries are larger than others (e.g., BEVs)
• The likelihood that many batteries will be only partially discharged when first
plugged in
Our model
–
–
–
–
Consumer BEVs average 100 miles in range vs. 40 miles for EREVs
80% of consumer BEVs are in the “top 20” metro areas
The majority of fleet vehicles will be BEVs
For this purpose, we only calculate fleet BEVs in the metro areas used
throughout this analysis
MW Load and Charging
Projections
Assumptions
–
–
–
–
–
Chargers – 20% level 1; 80% level 2
300 kWh per mile (includes travel, AC and accessories)
Night time charging assumed; daytime charging not included
Included both Consumer and Fleet projections
Individual utility load profiles were not considered
MW Load and Charging Projections
Slide 1 of 2
City Metro Area
New York
Total PEVs
MW Load if
everyone
charged at the
same time
MW Load if
charging is
staged over 8
hours
MW Load if
charging is
staged over 12
hours
54,069
448
40
26
119,069
988
174
116
Chicago
27,892
231
41
27
Washington, DC
37,520
311
55
37
San Francisco
91,005
755
133
89
Philadelphia
18,319
152
27
18
Boston
31,976
265
47
31
Detroit-Ann Arbor
10,718
89
16
10
Dallas-Fort Worth
10,961
91
16
11
Houston
12,032
100
18
12
Los Angeles
MW Load and Charging Projections
Slide 2 of 2
City Metro Area
Total PEVs
MW Load if
everyone
charged at the
same time
MW Load if
charging is
staged over 8
hours
MW Load if
charging is
staged over 12
hours
Atlanta
8,017
67
12
8
Miami
11,346
94
17
11
Seattle-Tacoma
26,088
216
38
25
Phoenix
15,831
131
23
15
Minneapolis
10,574
88
15
10
8,574
71
13
8
22,445
186
33
22
5,730
48
8
6
Denver-Boulder
11,230
93
16
11
Tampa-St. Pete
9,059
75
13
9
Cleveland-Akron
San Diego
St. Louis
Projected PEV Load
Total PEVs
Load if everyone
charged at the
same time (MW)
Load if charging
is staged over 8
hours (MW)
Load if charging
is staged over
12 hours (MW)
ISO-NE
61,074
338
75
50
NYISO
43,738
242
27
18
PJM
144,172
797
178
119
Midwest ISO
94,644
523
117
78
SPP
30,459
168
38
25
ERCOT
42,769
237
53
35
CAISO
267,654
1,480
331
221
TOTAL
684,510
3,785
819
546
ISO/RTO
22
Impact of Charging Patterns
PEV Load Impact - U.S. ISO & RTO Regions
4,000
Megawatts
3,500
3,785
3,000
2,500
2,000
1,500
1,000
819
500
546
0
Load if everyone
charged at the
same time
Load if charging is Load if charging is
staged over 8 hours
staged over 12
hours
23
PEV Products & Services
Emergency Load Curtailment (ELC)—PEVs are able to provide a quickresponse load-curtailment resource for emergency events, and may be
aggregated for maximum effect.
Dynamic Pricing (DP)—Dynamic pricing might be a way to accomplish
charging of PEV batteries in off-peak hours. However, further research
on consumer behavior is necessary to understand how a PEV owner
will respond to retail price differentials.
Enhanced Aggregation (EA)—The potential for high concentrations of
PEV loads in the evening makes managing charging over the day a
priority for the ISO/RTOs. This would be complementary to time-of-use
programs and be potentially linked to a dynamic-pricing product.
24
Conclusions
EV can be accommodated and managed within existing Ancillary
Services Products
Expanded use of electricity as primary fuel powering light-duty
vehicles poses a challenges and opportunities to the electricity
grid.
Management of PEV charging — at a minimum — can limit the
impact of new PEV loads and — at its best — provide new
resources.
In addition to testing and demonstrating new tools, grid
operators will be able to leverage experience with smart grid
technology and demand response to prepare for the unique
changes predicted to arrive with PEVs.
25
For More Information
A copy of the full report, Assessment of Plugin Electric Vehicle Integration with ISO/RTO
Systems, is available at the IRC website,
www.iso-rto.org.
26
ISO – New England
27
New York ISO
28
PJM Interconnection
29
Midwest ISO
30
Southwest Power Pool
31
Electric Reliability Council of Texas
32
California ISO
33