mobile air-conditioning actions for global warming reduction · mobile air-conditioning actions for...

Mobile Air-conditioning Actions for Global Warming Reduction　

　

Toshio Hirata

DENSO CORPORATION

JICOP　「ﾌﾛﾝ対策の現状と展望」 1/34 虎ノ門ﾊﾟｽﾄﾗﾙ　平成20年3月11日


1. Mobile Air Conditioning and Global Warming2. Refrigerant Emission Reduction3. Energy Efficiency Improvement


Mobile Air-conditioning and Global Warming


Compressor

CondenserExpansion Valve

MAC’s Refrigeration Cycle

cool air

Refrigeration Cycle

High press. & high temp. gas

Low press. & low temp. gas

Evaporator


GHG Effects on Global Warming (Japan)

Methane1.5%

Dinitrogen Monoxide2.7%

PFC0.7%

SF60.4%

Total Amount of

CO2Emission in

20021,330.8

[Mt CO2eq.]

HFC1.0%

CO293.7%

Industry37.2%

Energy Conversion6.4%

Waste Disposal2.0%Limestone

Consumption4.2%

Transport22.0%

Others0.0%

Residential12.7%

Business Use 15.5%

Breakdown of CO2 Emissionby Sectors


Influence of A/C on Fuel Consumption

A/C Off A/C on(yearly)

Fuel

Con

sum

ptio

n (k

m/L

)

5

10

15

25℃(50%RH)、No Solar Radiation

10Evaporator Outlet AirTemperature ( oC)

LowBlower Speed

FreshFresh / Recirculated Air

0Sun Load (W/m2)

50Humidity (%)

25Temperature ( oC)

Yearly

9 % Actual Running Mode: Compact Car LA4: Stop Ratio 17%


Example of TEWI Calculation (JAMA)

0

500

1000

1500

2000

2500

3000Emission into atmosphere at scrapping(future level)

Leakage in use, leakage ataccident and repair

Contribution by air-conditioner weight

Contribution for driving alternator

Contribution for driving compressor

TEW

I(kgC

O2)

FF2L S/D

3500Emission into atmosphere at scrapping(present level)

Direct(refrigerant)

In-direct(compressor power)


Refrigerant Emission Reduction(JAMA’s Action)

JAMA: Japan Automobile Manufactures Association


Reduction of refrigerant emission from HFC-134a A/C1.Recommend to use small refrigerant charge components;

• Target is 20% reduction from 1995 to 2010.• In 2004, the average of charge has been reached to 21% of

1995’s charge　(1995:700gram , 2004:553gram)2.Recovery and destruction of Refrigerant:

• Fluorocarbons Recovery and Destruction Law enforced from October, 2002.

• Reported recovery rate of scrapped vehicles is approx. 40%.• This law was incorporated into Automobile recycling law 　

from January, 2005.3.Recommend to use lower refrigerant leakage components;

• According to self-assessment of OEM, leakage in operation　has been reduced from 15g/yr• Field survey test was done from 2004 to 2005 to seek actual value.

JAMA’s Action Plan


Refrigerant Charge Reduction from 1995 to 2006

700

600

500

400

300

200

100

01995 1999

700650

2000 2001 2002 2003 2004

615 603588

553582

Ave

rage

cha

rge

(g)*

*Average refrigerant charge = Total charging amount at vehicle production

The number of produced vehicles

Reduced by 23%

2005 2006

548 536


741,516(+12.8%)

657,2722,375,493(+16.2%)

2,045,135Total

496,971372,0891,500,8281,083,231HFC-134a

244,545285,183874,665961,904CFC-12

2006200520062005

Recovered amount (kg)Refrigerant recovered vehicle numbers

The Refrigerant Recovery Data when scrapping in Japan


0

5

10

15

20

25

30

35

40

45

CFC-12 HFC-134a (1992) HFC-134a (2004)

Ref

riger

ant L

eaka

ge(g

ram

/yr)

Comp.

Hoses

Fittings

Others

Reduction in Refrigerant Leakage in Operation


Refrigerant Leakage Field Test(From April, 2004 to December, 2005)

LocationTokyo, Nagoya (average temperature 16C)

Number of test vehicles78 vehicles　(seven auto makers)

A/C systemSingle AC (16 type vehicles) Dual AC (6 type vehicles)

Charge amountSingle: Average: 516gram Max: 760gram Min:409gramDual: Average: 804gram Max: 1141gram Min:663gram

Driving distanceSingle: Average: 17,402km Max: 38,381km Min:1,952kmDual: Average: 20,590km Max: 40,983km Min:4,803km

Compressor running timeSingle: Average: 211.3hrs Max: 938.0hrs Min:24.4hrsDual: Average: 248.9hrs Max: 758.9hrs Min:51.5hrs

Compressor cycling numberSingle Average: 32,544 Max: 97,627 Min:253Dual Average: 36,302 Max: 98,777 Min:2178


0

2

4

6

8

10

12

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

Region: Tokyo & Nagoya (Normal load), average temp.: 16C

Leakage (g/yr)

Average leakage：Single: 8.6g/yrDual: 13.3g/yr

Dual (22 vehicles)

Single (56 vehicles)

Annual Refrigerant Leakage


Emission duringusage 899.3t/yr

Emission whenMAC broken

628.3t/yr

Emission whenvehicle is totally

lost 98.6t/yr

Emission at theend of life134.7t/yr

Emission whenmanufacturing

33.2t/yr

Total emission: 1794.1 ton/year

• 2.33 M CO2-ton/yr• 0.2% of baseline (1237 M CO2-ton/Yr)

Estimated Breakdown of Refrigerant Leakage from MAC in Japan

Reported to METI (Ministry of Economy, Trade and Industry)


Energy Efficiency Improvement

90% 10%

Driving Air-conditioning

MAC power saving

・Engine efficiency improvement ・Light weight of vehicle・Thermal management

Fuel Consumption

DrivingDriving


Trend of MAC Power Saving

201020092008200720062005200420032002200120001999199819971996199519941993

50

60

70

80

90

100

MA

C P

ower

Con

sum

ptio

n （％）

MFSTEP Ⅰ

MFSTEP Ⅱ

Sub-Cool condenser（MFSTEP Ⅲ）

SCS（oil separator）SC10S

E/G cooperationControl

MFSTEP Ⅳ

Humidity Control

SCX (intl. Heat exchanger)

40% reduction (compared to 1992)

More 25% reduction (compared to 2004)


Example of Energy Efficiency Improvement: Compressor

Suction Gas

When Suctioning

Suction

Starts Compressing

When Compressing

Rotary Valve


Example of Energy Efficiency Improvement: Compressor

Fig.7 Comparison of Suction Form

One Body Shell and Fixed Scroll

Suction Refrigerant Gas Flow(Peripheral Suction)

Suction Port set up Shell

Oil Separator


Example of Energy Efficiency Improvement: Sub-Condenser


Example of Energy Efficiency Improvement: Condenser

1980 1985 1990 1995 200040

60

80

100

120

140

160P

erfo

rman

ce Q

/F

2005Serpentine

Multi-Flow


Example of Energy Efficiency Improvement:Compact Evaporator

Conventional Type Enhanced type

3858


Example of Energy Efficiency Improvement: Engine-A/C Cooperation Control

Acceleration Signal 1

Output of Compressor Driving Capacity

ON

OFF

Large

SmallTime (Second)

Acceleration Signal 1


ON

OFF

Large

Small

Time (Second)

Cooperation Signal 1


ON

OFF

Large

Small

Time (Second)

ON

ON

OFF

OFF

Slow

Fast

Cooperation Signal 2

Driving Speed

Fuel Cut

Passing Acceleration Control

Start-up Acceleration Control

Acceleration Control Deceleration Control


Example of Energy Efficiency Improvement: System with Humidity Sensor

Tin20deg.

12deg.15deg.Te

Tout

Tem

p.

Tin

Evap.

Te

H/C

Tout

Power saving Control(External Variable Compressor)

Ambient temperature (℃)Ev

apou

t air

tem

p. (℃

)

DemistHumidity Comfort

Zone

Windshield humidity target: 90%

Cabin humidity Target: 60%

No Reheat

0 5 15 25 35

12

0

Minimum

dehumidificatio

n

w/o Humidity control

With Humidity control

Demist Line

Effect

Power Consumption Ratio

-20%

Conditions: 25°C-50% Blower: M1

With Humidity Control

w/o Humidity Control

0 1


Example of Energy Efficiency Improvement: Internal Heat Exchanger

Double-pipe internal heat exchanger

Evaporator

Compressor

CondenserOuter　tuber

Inner　tube


Cooling Performance Improvements

3.33.88

1.611.64

0

1

2

3

4

5

6

IHE

Coo

ling

Per

form

ance

(kW

)

Rear A/C

FrontA/C

+12% Bench Test

Conventionalsystem

Conditions: Large car, idling, ambient temperature 45° CVehicle test

Front20.3 Front

18.1

0

5

10

15

20

25

Fron

t and

Rea

r Pan

el O

utle

t　（℃）

-2.2℃

IHEConventionalsystem

Rear22.6

-2.0℃

Rear20.6


Fuel Consumption Improvement

Vehicle Speed

395 L(-5liter

or -1.3%)

(219.76 L with A/C ON)

400 L

(224.78 L with A/C ON)

Total Annual Fuel

Consumption

8.118.725.010.72.9ON

12.929.140.117.15.4ON

5. 613.918.78.92.8ON

8.018.625.310.73.0ON7.617.623.29.92.6OFF100

km/h

12.728.940.217.45.5ON11.325.033.313.73.8OFF40

km/h

ON 5.53.3

15° C

OFF

OFF

OFF

OFF

A/C

14.523.3

100km/h

40km/h

0km/h

0km/h 10.03.2

7. 610.24.71.4

Same as conventional system



35° C

Ambient Temperature & Fuel consumption (liter)

20° C25° C30° C

Con

vent

iona

lsy

stem

IHEConditions: Compact car, TEWI * evaluation in Tokyo, Japan

* TEWI: Total Equivalent Warming Impact


Example of Energy Efficiency Improvement: Recovery of Expansion Energy

■Ejector cycle

■Ejector

separatorejector

Driving flow

Suction flow

condenser

evaporator

compressor

Driving flow

Suction flow

nozzle Mixing region diffuser


Development of World First Ejector Cycle Refrigerator : EJECS

50% of Energy Efficiency Improvement!!

エジェクタサイクル, Ejector Cycle and EJECS are registered trademarks of DENSO corporation

Truck transport refrigeration unit using ejector


Truck Transport Refrigeration Unit using Ejector Cycle (EJECS)

Condenser

EvaporatorInsulation Panel

－Cross view of the structure－Front Back

Refrigerator compartment

Purpose: Compressor power saving and Fuel economy improvement

Purpose: Compressor power saving and Fuel economy improvement

CompressorEngine

COP (*1)

+50％COP (*1)

+50％Weight▲40％

Weight▲40％

－Over view of EJECOR －Adopt World First Ejector CycleAdopt World First Ejector Cycle


Result of Vehicle Monitor Test

Average　55845 (l)Average　63875 (l)Average　70750 (l)Annual fuel consumption (liter)

From 2003 December to2006 NovemberFuel consumption measurement: Fill up method

Period & Method

6107# of vehicles

Weight 186 kgWeight 234 kg Weight 560kg

Ejector Cycle Refrigerator(direct coupling)

Company A Refrigerator(direct coupling)

Company A Refrigerator(Sub engine system)

Refrigeration unit

Kyusyu-Kansai (611 km) long-distance transporter for highwayLoad: frozen and refrigerated food

Driving pattern

Load capacity: 10 tonClassificationExample: Large truck transportation refrigeration unit

▲22% ▲12%

Succeed to decrease fuel consumption by 12% to 22% compared to conventional refrigerators (sub-engine and direct coupling)


Large

Middle

Small

0

200

400

600

800

1000

1200

1400

Conventional Ejector

▲450,000CO2ton

▲320,000CO2ton

▲230,000 CO2tonThe number of servicing

(300,000 vehicles)

About 70,000 vehicles

About 30,000 vehicles

▲8.1％（▲1 million CO2 tons）

Large

Middle

SmallAbout 200,000 vehicles

CO2 Emission Reduction Effects based on All Refrigerated Vehicle in Japan

Effects of CO2 emission reduction by ▲1 million CO2 tons thanks to the ejector refrigerator

Effects of CO2 emission reduction by ▲1 million CO2 tons thanks to the ejector refrigerator

CO

2em

issi

on (

ten

thou

sand

s to

n)


Trend of MAC Power Saving

201020092008200720062005200420032002200120001999199819971996199519941993

50

60

70

80

90

100

MA

C P

ower

Con

sum

ptio

n （％）

MFSTEP Ⅰ

MFSTEP Ⅱ

Sub-Cool condenser（MFSTEP Ⅲ）

SCS（oil separator）SC10S

E/G cooperationControl

MFSTEP Ⅳ

Humidity Control

SCX (intl. Heat exchanger)

More 25% reduction (compared to 2004)


Current Situation for alternative refrigerant

MAC directive2008～　Directive 2006/40/EC (Emission of R134a)2011～　Banning the use of R134a for new type of vehicle2017～　Banning the use of R134a for new vehicle

EuropeVDA 2008/07 : decided to use CO2Other Not decided yet(French, Italy, US, Japan)↓Under evaluation of Low GWP refrigerant. We arediscussing about not only direct effect but energy efficiency (fuel consumption) by refrigerant. The point is LCCP estimate.

mobile air-conditioning actions for global warming reduction · mobile air-conditioning actions for...

Documents