ECEN 2060Spring 2008

V2G (Vehicle-to-Grid)

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What is V2G?

• BEV or PHEV

energy dispatched

to grid

• Direction of

power controlled

by utility or user

from http://www.udel.edu/V2G/docs/KemptonDhanju06-V2G-Wind.pdf

Grid layout with V2G used for wind energy storage

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Why V2G?

• Increasing

demands for peak

generation

• Massive lack of

wind energy

storage

• Backup

generation

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Why V2G: Peaking Power Plants

• Peak demand is

ever-increasing

• V2G fleet seen as

power plant

• No battery cost to

utility

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Why V2G: Wind Energy Storage

from http://www.udel.edu/V2G/docs/KemptonDhanju06-V2G-Wind.pdf

• Shortfall events

are lost energy

• V2G stores

irregular wind

energy

• No battery cost to

utility

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V2G Components

• Battery: 8-50kWh, 200-360V

• Power Electronics: Bidirectional, currently up to 20kW

• Control Systems: manages power flow, remote wireless control

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How V2G Works

Inverting:• PFC

• Anti-islanding

• Code

Charging:• Balancing

• Overcharging

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Hybrids Plus Inverger™

• Bidirectional

• Transformerless

• Multi-voltage (120V, 240V)

• Medium Power (6kW)

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Local V2G Fleet

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V2G and Smart Grid

Possibilities:

• Backup

• Renewables

• Load-leveling

• V2H

See Xcel website on Smart

Grid for the video clip used in

this slide:

http://tinyurl.com/2gp8gk

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V2G Example

V2G and System Specs:

• 6-Vehicle fleet, A-F

• 10kWh per V2G

• 6kW power per V2G

• 30kW excess demand

• 30kW wind turbine

• Simplified power behavior

• 100% of total 60kWh at start

• Grid operators control power

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Example Data

V2G Example: Power Data

-40

-30

-20

-10

0

10

20

30

40

4:00 PM 5:00 PM 6:00 PM 7:00 PM 8:00 PM 9:00 PM 10:00 PM

Time [Hr]

Po

we

r a

bo

ve

/be

low

ca

pa

cit

y [

kW

] Overcapacity Demand

Unused Wind Power

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Charging/Discharge Table

A-E @ 9kWh

F @ 10kWh

A-E charge @ 3kW

F charges @ 5kW-20kW9-10pm

A-E @ 6kWh

F @ 5kWhA-F charge @ 5kW-30kW8-9pm

A-E @ 1kWh

F @ 0 kWhA-E discharge @ 2kWF discharges @ 5kW

15kW7-8pm

A-E @ 3kWh

F @ 5kWhA-F discharge @ 5kW30kW6-7pm

A-E @ 8kWh

F @ 10kWhA-E discharge @ 2kW10kW5-6pm

EnergyBehaviorPowerTime

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V2G Battery Energy Levels

V2G Energies

0

2

4

6

8

10

12

4:00 PM 5:00 PM 6:00 PM 7:00 PM 8:00 PM 9:00 PM 10:00 PM 11:00 PM

En

erg

y S

tore

d [

kW

h]

V2Gs A-E

V2G F

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V2G Future

Technology:

• Hybrids

• PHEVS

• StorageSocial:

• Engineering

• Environmental Policy

• Citizen action