Electric VehiclesElectric Vehicles –Impacts & Opportunities

Ralph Boroughsp gElectrical Engineer,

Tennessee Valley AuthorityMusic City Power Quality Assoc.y y

November 1, 2011

The TVA Power Service Area

2

Quick Facts about TVA

•Established by Congress in 1933.•Board appointed by the President.•Funded solely by power revenue.y y p•Serving Tennessee and portions of 6 other states, ~9 million people., p p

•Generator, wholesaler and regulator.– 155 Power distributors – Municipals and Cooperatives.155 Power distributors Municipals and Cooperatives.– 59 Direct served accounts .

•Peak load 33,482 MW.

3

,

TVA Mission - Alignment with Electric TransportationAlignment with Electric Transportation

TVA Missions•Economic development. √•Environmental stewardship √•Environmental stewardship. √•Affordable electricity. √

åTechnological innovation. åIntegrated river system managementg y g

4

Environmental Assessment of Plug‐in Hybrid Electric Vehicles (EPRI/NRDC Study)lectric Vehicles ( PRI/NR C Study)

• Supported by TVA, other Utilities, and the Natural

400

450 

500 

2e/m

ile)

Coal Natural Non-,Resources Defense Council (NRDC)

• Volume 1 - PHEVs are a minimum of 30% better

200 

250 

300 

350 

400 

as Emission

s (g CO

2 Gas EmittingGeneration

minimum of 30% better than conventional vehicles for Greenhouse Gas Emissions ‐

50 

100 

150 

cle

cle

oal

oal

PC CC CS CC CC CC GT

GT

ear ar ass eseels Green

house Ga

• Volume 2 – PHEVs Improve Overall Air Quality

Ozone Conven

tional Veh

ic

Hybrid Ve

hic

PHEV

 ‐20

10 Old Co

PHEV

 ‐20

10 New

 Co

PHEV

 ‐Adv SP

PHEV

 ‐IGC

PHEV

 ‐IGCC

 with

 CC

PHEV

 ‐Old 201

0 C

PHEV

 ‐New

 201

0 C

PHEV

 ‐Adv C

PHEV

 ‐Old 201

0 G

PHEV

 ‐New

 201

0 G

PHEV

 ‐Nucle

PHEV

 ‐Adv Nucle

HEV

 ‐Ce

ntral Bioma

PHEV

 ‐Re

newabl

Well‐to‐Whe

– Ozone– Secondary PM2.5

– SOx

NO

P P

PH

Gasoline Well‐to‐Tank Gasoline Tank‐to‐Wheels Electricity Well‐to‐Wheels

Source: EPRI report 1015325: Environmental Assessment

5

– NOx Source:  EPRI report 1015325: Environmental Assessment of Plug‐in Hybrid Electric Vehicles, Volume 1

Annual greenhouse gas emissions reductions from PHEV adoption

600

reductions from PHEV adoption

• There is the potential

400

500

mission

smetric tons) 

for a 400-500 million metric ton annual reduction in GHG emissions by 2050

ti id (th US

200

300ee

nhou

se Gas Em

ctions (million mnationwide (the US

currently emits 6 billion metric tons annually)

0

100

2010 2015 2020 2025 2030 2035 2040 2045 2050

Gr

Redu

• Petroleum reduction of 3-4 million barrels per day by 2050

2010 2015 2020 2025 2030 2035 2040 2045 2050

Low PHEV Share Medium PHEV Share High PHEV Share• Reductions in TVA’s

territory are 4.7 MMTons by 2030 and 11.7 MMTons by 2050

6

o s by 050Source:  EPRI report 1015325: Environmental Assessment of Plug‐in Hybrid Electric Vehicles, Volume 1

CONSUMER STAKEHOLDER MAP

•Customer Interface•Vehicle

MAPValue

FUELCARCustomer Interface

•Integration / Interoperability•Smart Grid / Standards• Infrastructure•Rates

R&D•Safety•Consumer Marketing

•Price•Incentives

Automotive ElectricElectric

Economics•Rates•Smart Charging•Planning•Outreach / Call Center•Billing

•Battery•Recycling

Automotive OEM

Electric Electric Utilities C

onvves

•National Security •Safety

ConsumerEnergy Independence

Supporting

Goods & Services

venienceInce

ntiv

National Security•Carbon / GHG Emissions

•CAFÉ / Fuel Economy•Incentives / Tax Credits•Mandates•Public good

•Safety•Standards•Codes•Home Base•Public•Research Suppliers

InfrastructurePolicy

Environment

e

7

g•Economic Health•Environmental Health

•Suppliers•Planning & Development

•ContractorsEthos7

Traditional Consumer Fuel Paradigm

House = Consumer’s Largest Purchase Decision

Largest Consumer Purchases are traditionally mutually exclusive

P i id f ft it d

Strong Consumer / Utility Dynamic Exists

Power is paid for after its used

Fuel is prepaid prior to use

Traditionally NO Fueling at House

Vehicle = Consumer’s 2nd

Largest Purchase Decision

Many Public Fuel Choices

Decision

NO Utility Role

Consumer billed / pays AFTER power

8

Consumer NOT brand loyal to FUEL

AFTER power consumption

Utility has no role in vehicle purchase8

New Consumer Fuel Paradigm

Home = Primary Re-Fueling Location Utility RoleStrong Consumer / Utility

Dynamic Remains Existing customer dynamic with their

utility will NOT be changed by vehicle using electricity as a fuel

Consumer experience will be directly affected by utility engagement

Power Bill is increased from more kWh

Electricity is the FUEL

usage; Consumer NET COSTS decrease from transportation Fuel and O&M savingsMeter/Account

Number Provides Utility Visibility

9

Utility will maintain PRIMARY point of contact for electrical issue resolution

9

ELECTRICITY AS A TRANSPORTATION FUEL

20 

TRANSPORTATION FUELECONOMIC

1.05.0 

E ti t d F l C t/Mil if C t V hi lPrice of Residential Electricity & Regular

15 

d Veh

icle Types (Ce

nts pe

r Mile)

Standard 0.6

0.8

3.0 

4.0 

in Ten

nessee

 ($/kW

h)

enne

ssee

 Valley ($/G

al)

Gasoline Prices

Estimated Fuel Cost/Mile if Current Vehicles Presented with Historical Prices (¢/Mile)

Price of Residential Electricity & Regular Gasoline in TN, April 2006 to March 2010

5 

10 

ed Ann

ual A

verage

 Fue

l Costs ‐Standard

Plug‐in Electric Vehicle

Hybrid

Sedan

0.2

0.4

1.0 

2.0 

Average

 Retail P

rice of Electricity i

Regular Gasoline Price ‐A

verage

 for Te

El i i P i

($/Gal)

0 

Simulate

Electric Vehicle

0.00.0 

Electricity Prices

Source: EIA

($/kWh)

•TVA Electricity is equivalent to $0.75 ¢ per gallon of gasolineALL THE TIME!

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…. ALL THE TIME!•Electricity is consumer friendly - less volatile than gasoline and easier to estimate overall transportation fuel expense.

ELECTRICITY AS A TRANSPORTATION FUEL

TVA Hourly Seasonal Load Curves, Example Three-Day Periods in 2008

TRANSPORTATION FUELENERGY

35,000  Electric Transportation load will overlay an already-existing load pattern

Periods in 2008

30,000 

MW)

Winter

existing load pattern.

The Fuel Challenge: Smooth it out

25,000 

Hou

rly Sales (M

Summer

Winter Smooth it out

Options:Education

20,000  Smart ChargingTOUEV Rate

11

15,000 

1 3 5 7 9 11 13 15 17 19 21 23 1 3 5 7 9 11 13 15 17 19 21 23 1 3 5 7 9 11 13 15 17 19 21 23

Dual Peaking System – Summer & Winter

Why Utilities Should be Plug-In Ready

Central Air conditioning 3 – 20 kW

Water heater (40 gallon) 4.5 – 5.5 kW(40 gallon)

Clothes dryer 1.8 – 5 kW

Plug-in Electric Vehicle 1.44 – 7.2 kW

Unplanned “per capita” load growth

12

We do not yet know how consumers will

respond

First Plug-in Vehicles to Market Very Different Grid Impacts!Very Different Grid Impacts!

Chevrolet Volt– Extended Range Electric Vehicle

Nissan Leaf – Battery Electric Vehicle g

(EREV - A plug-in hybrid with a guaranteed electric range).

– 40-mile electric range– Charging:

8-9 hours at 120V 12A

y– 100-mile range– Charging:

20 hours at 120V, 12A 8 hours at 240V, 15A

30 min at 400V 150A DC

13

8 9 hours at 120V, 12A 3 hours at 240V, 15A

30 min at 400V, 150A DC

Charging ScenariosCharger AC Power Supply Charger Charge

Time

g g

Type Volts Continuous Current

Power Location

Level 1 110 12 A 1 4 kW On board 18 hLevel 1 110-120V

12 A 1.4 kW On-board

On-board

18 h

Level 2 220- 15 A 3.3 kW 8 h

On-board240V

32A(80A)

6.6 kW( 20 kW)

4 h(1.2 h)

‘Fast’,or ‘DC’

Input: 3 PhaseTypically 480V AC

50-60 kW DC into thevehicle

Off-board –Vehiclecontrols

<30 min

14

the charger

14

EPRI PEV Distribution Impact Study –A Collaboration Initiative

• Detailed analysis of circuits, PEV impacts

Near-term Planning HorizonLoad only operation

Near-term Planning HorizonLoad only operationimpacts

• 45 circuits at 25 utilities, including:• Nashville Electric Service

Customer behavior drivenMarket projectionsMainly residential charging

Customer behavior drivenMarket projectionsMainly residential charging

Nashville Electric Service,• Middle Tennessee EMC,• Chattanooga EPB,

Evaluated ImpactsFeeder demandTh l l d

Evaluated ImpactsFeeder demandTh l l d

g• Knoxville Utilities Board.• Memphis Light Gas & Water

Thermal overloadsSteady-state voltageLossesImbalance

Thermal overloadsSteady-state voltageLossesImbalance

• Compilation and comparison across different distribution systems.

Power qualityPower quality

15

y

Typical Asset Risk Analysis

Impact Unlikely

omer

per C

ust

Projected Demand CurvekVA

Potential risk

16

Customers per Asset

Key Findings – Asset Risk

•Greatest impact – transformer life.–Transformers with low kVA rating per customer.–At constant kVA/customer, fewer customers/

transformer reduce diversity, increase risk•PEVs loads exacerbate pre-existing problems.

–Undersized secondaries.•Long runs, smaller diameter •Length, diameter, often un-documented.

–Lower voltage primaries – e.g. 4 kV

17

General Study Findings – Phase I

Minimal near-term impacts expected

Negligible Impacts

Local Risks -Reliability Voltage

Planning AdjustmentsImpacts

• Losses

I b l

Reliability, Voltage

• Close to the customer

L i

Adjustments

• Equipment sizing

A• Imbalance

• Power Quality

• Primary Voltage

• Low capacity per customer

• Undersized secondaries

• Asset-to-customer allocations

• Transformer ratingsy g

18

Grid Impact Study – Phase II (pending)

• Area-Wide Asset Risk Planning and Evaluation Tool G & O• Generalize, Automate, & Apply Phase One Learnings

• Provide Utility tool for easy application• Broader than PEV Impact• Broader than PEV Impact• Scope - TBD

PEV Adoption Projection

Asset Risk Assessment

Quantify Impacts

Planning and System

UpgradesProjection Upgrades

19

SAE Power Quality Standards,- J2894

• PQ Standards for Chargers– Attainable goals– To protect utility, customers

To protect public interests (efficiency)– To protect public interests (efficiency)• Standards for AC Power Supply

– Attainable goalsAttainable goals• For utilities.• For alternate power supplies.

– To protect charger electronics.

20

SAE Power Quality Standards,- J2894Part 1 –Target parameters –in draftPart 1 Target parameters in draft

Power Quality Standards for Chargers –

Parameter SAE J2894 EPRI IWC (1990s)( )

Power Factor 95% 95%Power Transfer Efficiency

90% 85%y

%Total Harmonic Distortion (current)

10% 20%

Inrush Current 120% of nominal max Specified ValueInrush Current 120% of nominal, max. (after 50 ms, level 1)(after 100 ms level 2)

Specified Value

21

SAE Power Quality Standards,- J2894Part 1 –Target parametersPart 1 Target parameters

Cold Load Pickup – proposed

tility

lta

geU Vo

urre

ntC

u

1 Amp/second, max.

22

2 Minutes (minimum)

SAE Power Quality Standards,- J2894Part 1 –Target parametersPart 1 Target parameters

Power Quality Standards for AC Service

Voltage Range SAE proposed EPRI IWC (1990s)

Voltage Range 90-110% nominal 90-110% of nominal

Voltage Swell (1/2 cycle, minimum)

175% of nominal 180% of nominal

Voltage Surge 6 kV 6 kVg g(momentary)Voltage Sag 80% for 2 s 80%Voltage Distortion 2% max N/Ag %Momentary Outage 0 V for 12 cycles 0 V for 12 cyclesFrequency Variation +/- 2% +/- 2%

23

SAE Power Quality Standards,- J2894Part 2 –Testing Procedures - pendingPart 2 Testing Procedures pending

• Work has just begun.G C• Grid and Charger interaction– Charger PQ during Grid Sags & Surges

Charger Protection during Grid sags & Surges– Charger Protection during Grid sags & Surges• Scope of tests may be controversial.

– Limited to power conversion electronics?Limited to power conversion electronics?– Auxiliary loads?– Heating cooling loads?

• Efficiency standard driven by California’s need for “Low Carbon Fuel Standard”.

24

Chevy Volt

• A Chevy Volt was monitored during 250

300

16

18

20

Voltage Current

monitored during charging– 250 Volts, ave., 100

150

200

250

Volta

ge (i

n R

MS

Vol

ts)

4

6

8

10

12

14

16

Cur

rent

(in

RM

S A

mps

)

– 13 Amps, ave.• Complete charge

cycle 3 8 hours

0

50

0 50 100 150 200 250

Time (in Minutes)

0

2

4

Harmonic

cycle, 3.8 hours.• Sampled every 3

seconds. 6.00

8.00

10.00

12.00

14.00

onic

Mag

nitu

de

• 9.37% iTHDave.

• 1.42% vTHDave.0.00

2.00

4.00

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21

Harmonic Order

Harm

o

25

DC Fast Charger Demonstrations

• CHAdeMO system developed by TEPCO/JARIby TEPCO/JARI

• Widely deployed in Japan• Being deployed in US as part

f DOE j tof DOE projects• PG&E Demo underway

– Two sites (San FranciscoTwo sites (San Francisco and Vacaville)

– Ongoing testing of Mitsubishi i-MiEV andMitsubishi i-MiEV and Nissan Leaf at PG&E

• TVA /EPRI Solar Assisted Charging Station in Knoxville

26

Charging Station in Knoxville.

Charge Profiles for Leaf and i-MiEV- with DC Fast Chargerwith DC Fast Charger

Leaf

i-MiEV

27

Other Fast Charge Data

TEPCO Fast ChargerMay 5, 2011

50000

60000PG&E IMiEV and NY Times Demo IMiEV

PG&E IMiEV

NY Times  IMiEV

30000

40000

atts

20000

Wa

0

10000

1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35 37 39 41 43 45 47 49 51

i ( i )

11.4 kWh 10.7 kWh

28

Time (minutes)

Power Quality & Plug In Vehicles - SummarySummary

• PEVs will impact distribution circuits– Impact is local, manageable.– Planning tools are needed

• Charging profiles are being gathered• OEM Chargers appear to meet PQ StandardsOEM Chargers appear to meet PQ Standards• Prototypes – not so much• Additional work needed:

– Testing standards and procedures– Utility control for cold load pickup

29

Solar Charging Sites in Tennessee

TVA EPRI S C• Knoxville – EPRI Site Complete

• Nashville – Site Agreement• Memphis Site Agreement• Memphis – Site Agreement• Chattanooga – 2 Sites, 1 Agreement Oak Ridge National LabOak Ridge National Lab• ORNL Site Complete, • others pending in Knoxville, NashvilleNissan• Franklin HQ and Smyrna Factory

30

TVA- EPRI Solar Charging Stationwith six Chevrolet Voltswith six Chevrolet Volts

31

Nissan Leaf – ‘Anecdotal Experience’– not a scientific testnot a scientific test

• Mild Weather, 68-69 F (~20 C) No HVAC,• Moderate speed cruise control set at 38 mph• Moderate speed, cruise control set at 38 mph.• Level Ground, Oval Track.• First Warning at 94.6 miles, 11 miles more predicted.g , p• Second Warning at 110.3 miles, 4 miles more predicted.• Range Prediction then shows ‘----’• ‘Turtle Mode’ warning light at 118.8 miles• Cruise control drops out• Max speed begins to drop steadily• Coast to stop at 120.2 miles• Tow to charging station charge to 100% with 26 1 kWh

32

• Tow to charging station, charge to 100% with 26.1 kWh