Comparison of battery electric vehicles regarding their energy- … · 2016-02-04 · Lade-/Entladeverluste) Energiebereitstellung Climatic benefits Annual greenhouse gas emissions

Comparison of battery electric vehicles regarding their energy- and greenhouse gas emissions in

real operation

7th A3PS Conference - ECO-MOBILITY 2012 11th & 12th of December 2012, Tech Gate Vienna

Dipl.-Ing. Dr.techn. Werner Tober Univ. Prof. Dipl.-Ing. Dr.techn. Bernhard Geringer

7th A3PS Conference - ECO-MOBILITY 2012 Comparison of battery electric vehicles regarding their energy- and greenhouse gas emissions in real operation

11th & 12th of Dec. 2012 | Vienna | W. Tober | Slide 2

Contents

¨  Motivation and objectives

¨  Methodology and measurement technology

¨  Vehicles assessed

¨  Results -  Determination of the range -  Energetic benefits -  Climatically benefits

¨  Summary

¨  Outlook



Motivation and objectives

¨  Electro mobility is widely regarded as the solution for the future mobility.

¨  Politics and media see an effective way in the electrification -  to increase the energy efficiency -  to reduce the dependence on fossil fuels and -  to significant lowering the greenhouse gas emissions.

¨  How big are the advantages of battery electric vehicles -  based on real operating conditions over an entire year and -  the energy supply is taken into account?



Proceeding

¨  To analyse the benefits, four battery electric vehicles were examined.

¨  A diesel-engined car with combustion engine served as a reference vehicle.

¨  To compare the real annual energy requirements and the real greenhouse gas emissions, we set out to: -  the temperature curves for Austria and European Union over a periode of one

year. (Focus: heating and air conditioning) -  examine the influences of the driving conditions in urban, extra urban, motorway

and stop-and-go situations. -  examine the influences of the road gradients +2 %, -2 % and +/-2 % -  take account of the greenhouse gas emissions generated as part of the energy

provision as well as the energy required for the provision.

¨  In addition we also -  determined the ranges of the vehicles -  determined the efficiency of the current transformers and traction battery -  calculated the annual energy costs.



Examineded test cycles Eco-Test and Stop-and-Go

¨  The Eco-Test cycle consist out of existing test cycles with an overall length of 35,506 km.

0

25

50

75

100

125

150

0 500 1.000 1.500 2.000 2.500 3.000

Spe

ed [k

m/h

]

Time [s]

Test cycles Distance [km] NEFZ ECE 3,920 CADC Urban 4,930 Urban 24,93%

Test cycles Distance [km] NEFZ EUDC 6,920 CADC Extra Urban 8,966 Extra urban 44,74%

Test cycles Distance [km] BAB 130 9,270 Access/exit 1,500 Motorway 30,33%



Measurement setup To determine the losings and to set up a energy balance

¨  Current and voltage measurement to determine the electric demand and power.

E- motor

Inverter DC/AC

On-board Charger

High-voltage battery

220 V mains

Air

cond

ition

ing

Heating

Transmission

DC/DC converter

N1 to N6: low-voltage consumer units such as coolant pump e-technology, coolant pump vehicle interior, vehicle interior fan, seat heaters etc.

Low-voltage battery N1 N2 N6 …

220 V ~ 300 V = 12 V = 300 V ~

Measuring system



Measurement technology requirements

¨  Currents up until 500 A.

¨  Voltage up until 600 V.

¨  Current sensors need to have: -  high linearity -  low offset -  high band width -  small phase error -  temperature stability

¨  No interaction of the current measurement from the car electronics

¨  High sampling rate (up until 400 kHz necessary, depends on the inverter).

¨  Variable sampling rate (e.g. temperature at 1 Hz)

¨  High processing power for high processing rates (up until 200 kHz, in real time)



Vehicles assessed

ICE passenger car

¨  Volkswagen Polo BlueMotion

E-car

¨  Mitsubishi i-MiEV

¨  Smart Fortwo Electric Drive

¨  Mercedes Benz A-Klasse E-Cell

¨  Nissan Leaf

Photo: Heinz Henninger

Photo: Heinz Henninger Photo: Heinz Henninger

Photo: Heinz Henninger Photo: Heinz Henninger

Diesel

Li-Ion Li-Ion

Li-Ion Li-Ion



Contents

¨  Motivation and objectives

¨  Methodology and measurement technology

¨  Vehicles assessed

¨  Results -  Determination of the range -  Energetic benefits -  Climatically benefits

¨  Summary

¨  Outlook



101 108

88 73

66 57

0

20

40

60

80

100

120

140

160

180

200

+30°C +20°C +10°C 0°C -10°C -20°C Ambient temperature in °C

Range of the Mitsubishi i-MiEV Battery capacity as stated by manufacturer: 16 kWh Measured: 14,1-15,3 kWh

¨  Average demand in the Eco-Test at -20 °C: e-motor 5,7 kW

heating 3,8 kW

Heating Air conditioning

road gradient 0 %

Interior temperature 22 °C

↓... Energy reserve 25 km

Test cycle: Eco-Test

kWh/100km… at driving operation

21,0*

kWh/ 100km

13,6 kWh/

100km

Ran

ge in

km

at

max

imum

rang

e ac

hiev

able

*…incl. heating



Range of the Mercedes Benz A-Klasse E-Cell Battery capacity as stated by manufacturer: 36 kWh Measured: 32,4-34,7 kWh

¨  Caused by the higher battery capacity, -  and the higher energy demand, affected by the vehicle category, -  is it possible the reach higher ranges.

147

175

147

126 110

90

0

20

40

60

80

100

120

140

160

180

200

+30°C +20°C +10°C 0°C -10°C -20°C

26,2*

kWh/ 100km

19,8 kWh/

100km

Heating Air conditioning

road gradient +/- 2 %

Interior temperature 22 °C

↓... Energy reserve 25 km

Test cycle: Eco-Test

kWh/100km… at driving operation

Ran

ge in

km

at

max

imum

rang

e ac

hiev

able

*…incl. heating Ambient temperature in °C



Energetic and climatic benefit Outline conditions

¨  For the comparison, an average battery electric vehicle gets compared with a car with a combustion engine (VW Polo).

¨  Under consideration are taken: -  average road gradients -  different driving situations (urban, extra urban, motorway and stop-and-go). -  User behaviours -  Urban motorist (7.500 km per year, 65% stop-and-go and urban) and -  Interurban motorist (15.000 km per year, 65% extra urban and motorway).

-  charging/discharging losses of the high voltage battery. -  The operation of the heating system or air conditioning system based on the monthly

average temperature (Austria and EU) -  The energy required for the provision (Austria and EU).

¨  The energy required to manufacture the high-voltage battery and the vehicle are not taken into account.



Energetic benefits Annual energy requirement of an urban motorist ¨  The energy requirement for the energy provision of an e-car is higher than for

an diesel car.

¨  The lower share of renewable energy in the energy provision in the EU is leading to an energetic disadvantage of the e-car compared to the diesel car.

1.010 617

1.836 3.214

0

2.000

4.000

6.000

8.000

10.000

12.000

E-PKW Diesel-PKW

Betrieb des Fahrzeuges (inkl. Lade-/Entladeverluste) Energiebereitstellung

3.104

420

1.709

3.207

E-PKW Diesel-PKW

Ener

gy d

eman

d in

kW

h/ye

ar

74% 100% 133% 100%

e-car Diesel car e-car Diesel car

Running of the vehicle (incl. charging/discharging losses) Energy provision

Kilometric performance: 7.500 km per year, 65% Stopp-and-Go and urban Austria Europe



359 180

777

0

500

1.000

1.500

2.000

E-PKW Diesel-PKW

Betrieb des Fahrzeuges (inkl. Lade-/Entladeverluste) Energiebereitstellung

Climatic benefits Annual greenhouse gas emissions of an urban motorist

¨  The greenhouse gas emissions for the electric energy provision is higher than the one for diesel

¨  The advantages compared to a diesel car can be shown as well in Europe.

GH

G in

kg

CO

2e/y

ear

820

194

794

E-PKW Diesel-PKW

38%

100% 83% 100%

Austria Europe Kilometric performance: 7.500 km per year, 65% Stopp-and-Go and urban

e-car Diesel car e-car Diesel car

Running of the vehicle (incl. charging/discharging losses) Energy provision



¨  Range -  The range achievable by the testes e-cars that are currently on regular scale in

the motor trade is severely limited compared with conventional vehicles and dependent on the ambient temperature.

-  These particular circumstances are not expected to change in the long term either.

¨  Energy requirement -  Also under real-life conditions (driving and ambient temperature), the energy

consumption of an average e-car in pure driving operation (excluding the energy supply) is just 60% of the energy of a conventional diesel-powered car.

-  In Austria, the holistic approach leads to a reduction of the benefits, so that the e-car has an energy requirement of 74 to 79% of a diesel-powered car.

-  An energetic disadvantage of e-cars from 33 to 43% compared to diesel car results from the consideration of the energy provision in the European Union.

Summary Range and energy requirement



¨  Greenhouse gas emissions -  The high proportion of renewable energy in Austria is also responsible for

causing that a e-car in Austria are only responsible for 38-40% of greenhouse gas emissions compared to a diesel car.

-  However, an e-car in the European Union produces 83 to 90% of the greenhouse gas emissions compared to a diesel car, if greenhouse gases for the energy provision are taken into account.

Summary Greenhouse gas emissions



¨  The 2nd edition of the Study „Battery Electric Vehicles in Practice- Costs, Range, Enviroment, Convience“ is on www.oevk.at for download available. -  Study and detailed data's are free available -  New: Citroen Berlingo -  Molten salt battery (ZEBRA) -  Gasoline heater as interior heater -  No air conditioning -  Range (+ 20 °C à -20 °C): 85 à 68 km -  Fuel consumption of the interior heater (+ 10 °C-> -20 °C): 0.4-1.3 l / 100 km -  energy from 230V network to preserve the battery operating temperature

(+ 20 °C à -20 °C): 100 à 229 WH/h

¨  The current project is focused on the optimization of PHEV- and REX vehicles.

¨  The focus is equally on the ICE- and the e-drive, as well as on the interaction of both drives.

Outlook

Foto: Johann Wolf

Thank you very much for your kind attention!

Dipl.-Ing. Dr.techn. Werner Tober [email protected]

Documents

Comparison of battery electric vehicles regarding their energy- … · 2016-02-04 · Lade-/Entladeverluste) Energiebereitstellung Climatic benefits Annual greenhouse gas emissions