Vehicle to Grid Power
Presented to
Delaware Public Service Commission
7 July 2009
by
Willett Kempton, Director
Center for Carbon-free Power Integration
College of Earth, Ocean, and Environment
University of Delaware
Overview
• Vehicle-to-Grid (V2G)
• Car as underutilized resource
• How much power available?
• Vehicles as A/S providers
• Control of car by ISO
• Software for aggregation of vehicles
• Car production, Fleet Expansion
vehicle-to-grid Power
Plug-in for charging
V2G with ISO Control
V2G taps an underutilized
resource
• US car used 1 hour/day, parked 23 h/d
• Daily travel = 35 mi, battery 100-200 mi
• Thus, most storage unused most days
• Drive train output = 100 kW
• Practical power through grid = 10 - 20 kW
• Cars as significant power? Compare:
• Vehicle fleet at 15 kW each car, with
• Total load for country (GW)
How Much Power in cars?
Denmark
UK
USA
Light vehicles
6
(10 )
1.9
28.5
191
Vehicle GW
(@ 15 kW each)
29
427 2,865
Avg. Electric
Load (GW)
3.6
40
417
Initial Market -- Ancillary
services
• First Market: Ancillary Services (A/S)
• Higher revenue, especially regulation
• ISO control via Automatic Generation
Control (AGC)
• Revenue sufficient for business launch
Energy Markets
North American RTO/ISOs
PJM as Part of the US Eastern Interconnection
Key Statistics
PJM member companies
470+
Millions of people served
51
Peak load in megawatts
144,796
MWs of generating capacity
165,303
Miles of transmission lines
56,070
GWh of annual energy
728,000
Generation sources
1,271
Square miles of territory
164,260
Area served
13 states + DC
6,038
substations
26% of generation in
Eastern Interconnection
23% of load in
Eastern Interconnection
19% of transmission assets
in Eastern Interconnection
19% of U.S. GDP produced in PJM
www.pjm.com
11
©2006 PJM
Value of regulation
Average Annual Market Clearing Price
($/MW-h)
2004
2005
2006
PJM
$42.75
$49.73
$32.69
RTO-NE
$28.92
$30.22
$24.02
NY ISO
$22.59
$39.21
$51.26
ERCOT
$22.66
$38.07
n/a
CA ISO
$29.00
n/a
$36.04
Value per Vehicle
10 –Year Present Value V2G Revenue Potential
Assumptions: 80% availability, Reg. $40/MW-h, Spin.
$10/MW-h, 7% discount rate, example calculations
Sequence of Markets
• Initial, high-value markets, are ancillary
services (A/S)
• Regulating power (“Regulation”)
• Spinning reserves (synchronous
reserves)
Sequence of Markets
• Later -- larger markets, lower value per kW
• Defer upgrades to distribution feeders,
transformers
• Peak load reduction, valley filling
• Power factor correction
• Balancing wind, reducing ramp rate
• Shifting solar peak to load peak
Control of car by ISO
(Grid operator)
AGC from PJM to Vehicle via
PLC
What the ISO sees
What the ISO sees
EVs providing regulation
Regulation, drive, regulation, drive
Permitted by Load-Serving Entity
(local utility)
Permitted by Load-Serving Entity
(local utility)
“meets IEEE 1547 standards”
Bill to codify interconnect Permits
Define:
Aggregator
Grid-integrated
electric vehicle
Bill to codify interconnect Permits
Continued...
Net metering
Net can be at rate at time of use (not in this case)
Interconnection requirements, etc
same as distributed renewables
Changed to ISO coalition - vehicle smart
link
ISO link now on server
Vehicle Smart link (VSL) in
Car
• No moving parts, fits
under dash
• Receives signal from
coalition server
• Reports capacity and
current state back to
coalition
• Working to predict next
use of car (time, distance)
• Automotive-grade Linux
computer
From car-as-generator
to fleet as generator
• AGC signal to a server used by
aggregator
• Server runs an agent-based coalition
manager, dispatches individual vehicles
• Vehicle Smart Link (VSL) on each vehicle
learns pattern of use of that vehicle,
predicts ability to dispatch
• Vehicle module acts reasonably when
communication lost (e.g. night charge)
V2G Aggregator
Leveling Wind with V2G
Simple model of V2G for
wind leveling
•
220 MW offshore wind power (modelled from buoy 44009)
•
Leveling target at 88 MW (40% of nameplate or 14%
of average DE load over 8760 hours)
•
EV storage of 1000 MWh (1 GWh) to level
•
Storage from just under 30,000 EVs (28571
eBoxes), about 4% of DE fleet
•
Simplifying assumptions: no other end use storage,
no distribution power limits, driving compromised
during a few long wind lulls/year
•
Equivalent proportion: 3,250 MW capacity (100% of
DE electricity) and 58% of fleet
July Wind
July wind + V2G
January Wind
January wind + V2G
V2G as wind leveling
• Good to reduce ramp rate, fill short gaps
(up to 6 hours? one day?)
• Simple model: Not suitable for multi-day
wind lulls
• Still need fossil or some other backup
for long wind lulls
• Half of fleet serves very roughly 100%
wind electric -- needs model with load,
etc
Experimental Fleet
Current Fleet
• AC Propulsion
eBox
• Fuel Cell Bus
Fleet expansion
• Now building 5 vehicles
• Market test requires enough vehicles, at
15 kW/vehicle that is
• V2G market test in PJM: 200 cars = 1
MW
• V2G test in ISO-NE: 20 cars = 100 kW
• OEMs not building grid-oriented cars, so
we work with medium-volume (300/year)
manufacturers
medium-volume manufacturing
AutoPort, Inc. converts vehicles, will do EVs with V2G
Fleet expansion
Summary
• Electricity has “won” as next car fuel
• Plug-in cars will be a grid resource
• A/S as initial high-value markets
• Completed or in process
• 1-6 vehicle dispatch under AGC
• Software for aggregator & vehicle
• Interconnect; law for net metering
• Next: Fleet for A/S contract (~200+)
END
More information:
www.magicconsortium.org
www.carbonfree.udel.edu