Final Report by
Heavy Vehicle Fuel Efficiency Standard Evaluation Group,
Heavy Vehicle Standards Evaluation Subcommittee,
Energy Efficiency Standards Subcommittee of the Advisory
Committee for Natural Resources and Energy

This subcommittee/evaluation group discussed various items necessary for heavy vehicle
manufacturers and importers (hereafter referred to as “manufacturers”) to evaluate the energy
consumption efficiency (fuel efficiency) of heavy vehicles, and prepared the final report as shown below.
1. Target Scope (See Attachment 1)
Diesel fuelled freight vehicles and passenger vehicles (riding capacity of 11 persons or more) having agross vehicle weight of 3.5 tons or larger, either type designated under the Road Trucking Vehicle Law(1951, Law No. 185) Article 75.1 (type designated vehicle), or those equipped with a CO and othersubstances emission preventive device under Article 75.2.1 of the same Law (vehicle equipped with a COand other substances emission preventive device).
2. Items to be the standards for judgment by manufacturers(1) Target fiscal year (See Attachment 2)
FY2015: this deadline was determined so that the manufacturers can be given enough time fordevelopment toward better fuel efficiency.

During this period, they may have at least one or two

opportunities for launching modified models with the fuel efficiency improved toward the target values.
(2) Energy consumption efficiency (fuel efficiency) measurement methods (See Attachment 3)
Energy consumption efficiency (fuel efficiency) evaluations shall use the simulation method with two
different driving modes: urban driving mode (JE05 mode) and interurban driving mode (80 km/h constant
speed mode with longitudinal grade) (combination of these two modes is referred to as “heavy vehiclemode”).
Energy efficiency (fuel efficiency) is a weighted harmonic average of measurements in both driving
modes (“urban driving mode fuel efficiency” and “interurban driving mode fuel efficiency” in kilometer
per liter) obtained with the relevant factors shown in the following table.

The efficiency is also ameasured (examined) value by the Minister of Land, Infrastructure and Transportation in the course ofdesignating vehicle type or CO and other substances emission preventive devices (hereafter, the efficiency
is referred to as “heavy vehicle mode fuel efficiency”).
In order to measure fuel efficiency, we shall define a standard vehicle type (plain body) for each vehicle
category since heavy vehicle greatly vary each other in terms of design feature such as vehicle type. Also,for each category, besides driving resistance common for all manufacturers, final reduction gear ratio andtire’s dynamic load radius of representative specifications shall be used in the measurement.

Table

Driving Distance Proportion by Driving Mode
Passenger vehicles

Freight vehicles(riding capacity : 11 persons or more)
Vehicle type
GVW

Ordinary bus

Route bus

Other than tractor

Tractor

14 tons orOver 1420 tons

Over 20

20 tons

Over 20

less

tons

or lesstons

or less

tons

1

Drive proportion
Upper: urban mode

0.9

0.65

1.0

0.9

0.7

0.8

0.9

Lower: interurban mode

0.1

0.35

0.0

0.1

0.3

0.2

0.1

E=１/｛(αu/Eu + αh/Eh）
Where,E: Heavy vehicle mode fuel efficiency (km/l)

Eu: Urban driving mode fuel efficiency (km/l)

Eh: Interurban driving mode fuel efficiency (km/l)

αu : Proportion of urban driving mode
αh : Proportion of interurban driving mode

(3)

Target Standard Values (See Attachments 4, 5)
For heavy vehicles shipped in Japan in each of the target fiscal year and subsequent years,

manufacturers shall ensure that weighted and averaged energy consumption efficiency (fuelefficiency) in (2) by their shipped units shall not be below the relevant standard target value for eachof vehicle categories.
○Freight vehicles<Other than tractor>
e Category

Gross Vehicle Weight
Range (t)Maximum Load Range (t)Target Standard Values（km/l）

≦1.5

10.83

1.5<&≦2

10.35

2<&≦3

9.51

3<

8.12

1
2
3

3.5<&≦7.5

4
5

7.5<&≦87.24

6

8<&≦106.52

710<&≦126.00

812<&≦145.69

914<&≦164.97

10

16<&≦20

4.15

11

20<

4.04

<Tractor>
VehicleGross Vehicle Weight

Category

Range (t)

1

≦20

3.09

2

20<

2.01

Target Standard Values（km/l）

2

○Passenger vehicles (Riding capacity :11 persons or more)<Route bus >VehicleGross Vehicle Weight

Category

Range (t)

1

6<&≦8

6.97

2

8<&≦106.30

310<&≦125.77

412<&≦14

5.14

5

14<

4.23

VehicleGross Vehicle Weight

Category

Range (t)1

3.5<&≦6

9.04

2

6<&≦8

6.52

3

8<&≦106.37

410<&≦125.70

512<&≦145.21

614<&≦16

4.06

7

16<

3.57

Target Standard Values（km/l）<Ordinary bus>
Target Standard Values（km/l）(Reference)
Given the target standard values are as above, assuming that the proportion of the number of shipped
units for each vehicle category remains unchanged in the target fiscal year (FY2015) from FY2002, theimprovement ratio of average fuel efficiency (weight-averaged fuel efficiency by the number of shipped
units) from the actual values in FY2002 to the estimate values in FY2015 shall be calculated as shown
below.
○Freight vehicles
Improvement ratio

FY2002, actual values

FY2015, estimate values

Other than tractor

6.56(km/l)

7.36(km/l)

12.2%

Tractor2.67(km/l)

2.93(km/l)

9.7%

Total

6.32(km/l)

7.09(km/l)

12.2%

of fuel efficiency○Passenger vehicles (Riding capacity :11 persons or more)
Improvement ratio

FY2002, actual values

FY2015, estimated values

Route bus

4.51(km/l)

5.01(km/l)

11.1％

Ordinary bus

6.19(km/l)

6.98(km/l)

12.8％

Total

5.62(km/l)

6.30(km/l)

12.1％

3

of fuel efficiency

(4)Display Items (See Attachment 6)

1]

The following items shall be displayed.

2]

a.

vehicle name and typeb.

Type, total displacement, maximum power and maximum torque of enginec.

Vehicle kerb weightd.

Transmission type, number of gears, and gear ratiose.

Fuel supply equipment typef.

Major measures to improve fuel efficiencyg.

Energy consumption efficiency (fuel efficiency) (unit: km/l)h.

Manufacturer’s nameCompliance items(a)

All the items specified in 1] shall be displayed in catalogs for the applicable heavy vehicles.

Inthis case, the item g shall be displayed in such a manner that it stands out (e.g. by underlining,
using a larger typeface, or changing the color of the characters).
(b)

For heavy vehicles used for exhibition, all the items specified in 1] shall be displayed clearly inan easy-to-see place.

3]

OthersTo describe the item g, fuel efficiency in a driving mode relevant to city drive (hereafterreferred to as “city driving mode”) that is one of JE05 modes (hereafter referred to as “city driving
mode fuel efficiency”) or interurban drive mode fuel efficiency may be displayed in addition to theheavy vehicle mode fuel efficiency.

3.

Proposal for energy-saving(1)

Actions of Government1]

For the purpose of spreading heavy vehicles which have excellent fuel efficiency, government
supports, including efforts to spread awareness, shall be given to help the users and manufacturers
take appropriate energy saving measures and efforts. Social conditions such as oil price shall also
be factors that determine the details of the governmental supports.

2]

To apply the judging standards, considerations shall be given to manufacturers’ efforts for energy
saving and emission control regulations, as well as other circumstances, so that these activities canproceed consistently with those required to achieve the target standard values.

3]

As for reduction of driving resistance, one of fuel efficiency remedies, there is no methods
available to evaluate it individually based on specification of each vehicle.

Therefore, the present

measurement methodology uses a fixed value of driving resistance for each of vehicle categories
so that the target standard values are set without reflecting fuel efficiency improvement due toreduction of driving resistance.

Also, the presently available fuel consumption simulation

technologies are not applicable to AT and AMT (automated manual transmission) vehicles.
Therefore, the fuel consumptions of these vehicles are calculated based on simulated fuel4

efficiency, assuming them as corresponding manual transmission vehicles with the same number oftransmission gears and gear ratios.

However, it is likely that reducing the driving resistance willlead to significant improvement in fuel efficiency, and innovative technologies available for AT
and AMT vehicles will improve the fuel efficiency. Thus, efforts shall continue to find such
evaluation methods that can reflect the reduction of driving resistance and improvement of fuelefficiency specific to AT/AMT transmission systems.
4]

For heavy vehicles, depending on the technologies applied, there is normally a trade-off between
improvement of fuel efficiency and reduction of exhaust gas emissions.

When studying measures

for improving fuel efficiency of heavy vehicles, it should be noted that these fuel efficiency targets
have been determined in consideration of the 2009 exhaust gas emission control (the post new
long-term control).
5]

Energy-saving standards determined based on the Top Runner Program are very effective forpromoting energy-saving.

Take appropriate opportunities for presentation to spread thesestandards across the world.
(2) Actions of manufacturers
1] Technological developments to improve the fuel efficiency of heavy vehicles shall be promoted,
and those with excellent fuel efficiency shall be developed.
2] To spread heavy vehicles that have excellent fuel efficiency, users shall be given appropriate
information concerning the fuel saving advantages of these vehicles.
(3) Actions of users
Users are expected to select heavy vehicles with excellent fuel efficiency, and to make efforts to
reduce fuel consumption through using the vehicles in an economical and efficient manner.
4.

Challenges
For heavy vehicles, depending on the technologies applied, there is normally a trade-off between

improvement of fuel efficiency and reduction of exhaust gas emissions.

If necessary, these fuel efficiency

standards shall be further studied in consideration of exhaust gas emissions reduction efforts along with theimplementation of the 2009 exhaust gas emission control.
Once the methods which appropriately evaluate effects of reducing driving resistance and improving fuelefficiency in AT/AMT vehicles are developed, possibility of reflecting the effects in the evaluation
standards shall be reviewed.

5

Attachment 1

Target Scope
Currently, heavy vehicles that are within the scope of these fuel efficiency standards based on the Law
concerning the Rational Use of Energy (hereinafter referred to as the “Energy Conservation Law”) are
diesel fuelled freight vehicles and passenger vehicles (riding capacity:11 persons or more) having a grossvehicle weight of 3.5 tons or larger; they are either type designated under the Road Trucking Vehicle Law(1951, Law No. 185) Article 75.1 (hereinafter referred to “type designated vehicle”) or equipped with a COand other substances emission preventive device under Article 75.2.1 of the same Law (hereinafter referred
to “designated vehicle equipped with a CO and other substances emission preventive device”).
Among vehicles having a gross vehicle weight of 3.5 tons or larger, those fuelled other than diesel oil,and those diesel fuelled but not “type designated” or “equipped with a CO and other substances emission
preventive device” have been excluded from the scope, since the market of these vehicles is small, andthere are some technical problems regarding measurement.

However, while monitoring shipment volumeof these vehicles, decisions shall be made to determine whether those categories of vehicles shall be
included in the scope, and necessary studies shall be performed.
(*)Passenger vehicles (restricted to holding 10 persons or less) and freight vehicles with a gross vehicle
weight of 2.5 tons or less (hereinafter referred to “passenger vehicles”) that have now been placed
under the fuel efficiency control are under examination by the joint meeting of Automobile Standards
Evaluation Subcommittee (under Energy Efficiency Standards Subcommittee of the Advisory
Committee for Natural Resources and Energy) and Automobile Fuel Efficiency Standards
Subcommittee (under Traffic Policy Council, Land Transportation Section) (hereinafter called thePassenger Vehicles and Other Vehicles Fuel Efficiency Standards Joint Evaluation Meeting) toward thenext fuel efficiency standards that are planned to be established in early 2006.
(*)Freight vehicles with a gross vehicle weight over 2.5 tons but 3.5 tons or less and passenger vehicles
with a gross vehicle weight of 3.5 tons or less (riding capacity: 11 persons or more) are now out of thescope of fuel efficiency standards.

However, these categories of vehicles use the same exhaust gas

emissions measuring methods as those applicable for other categories of passenger vehicles.
Therefore, the Passenger Vehicles Fuel Efficiency Standards Joint Evaluation Meeting is investigating
new fuel efficiency standards applicable for these vehicles in parallel with those for the other vehicles.

6

Attachment 2

Target Fiscal Year for Heavy Vehicles

Major improvements in fuel efficiency may occur when launching new models. New model launchingcycles for heavy vehicles is said to be 5 to 10 years. Improvements in engines and drivetrains tend tooccur when exhaust emissions reduction technologies are applied or modified to cope with exhaust gas
emission control.

However, since, depending on the types of fuel efficiency improving technologies

applied, there may be a trade-off between exhaust gas emissions reduction technologies and fuel efficiency
improving technologies, they may be implemented simultaneously. Considering this, there should be atleast one or two cycles for launching new models, which can be an opportunity for applying or modifying
fuel efficiency improvement measures, within the period up to the target year.
From the viewpoint of global warming countermeasures, it is desirable that heavy vehicles which haveachieved the target standard values will have been significantly spread by the first commitment period(from 2008 to 2012) of the Kyoto Protocol.
Meanwhile, the 2009 exhaust gas emissions control (the post new long-term exhaust gas emissions
control) is slated to be introduced in 2009 (2010 for some vehicles types).
are required to give first priority in addressing the control.

Heavy vehicle manufacturers

Therefore, during the term up to 2009/2010,

taking the trade-off described the above into consideration, it will be the task to suppress the decrease offuel efficiency caused by the control.

In other words, during this term, it may be difficult to achieve therequired improvement in fuel efficiency.
Given the above, the target year for achieving the target standard values for heavy vehicles is set to
FY2015, that is five years after the post new long-term exhaust gas emissions control, so that heavy vehicle
manufacturers can have enough period for developing technologies for achieving the fuel efficiency goals.

7

Attachment 3

Energy Consumption Efficiency (Fuel Efficiency) Measurement Method for Heavy Vehicles

Depending on the types of fuel efficiency improvement technologies applied, there may be a trade-off
between fuel efficiency improvement and exhaust gas emissions reduction.
should be evaluated simultaneously under the same conditions.

Therefore, these two aspects

Moreover, to reduce burden to be born for

the vehicle manufacturers, fuel efficiency measuring systems should be as common for measuring exhaustgas emissions as possible.
(For information only) Exhaust gas emissions measurement method available for heavy vehicles:
To measure exhaust gas emissions of a heavy vehicle, for reason of its heavier body and weight,
engine-based measuring methods (using an engine dynamometer to evaluate the engine as a separate unit:
stand-alone engine measurement) has been used in place of vehicle-based methods. For the new short-term
control (since 2003), the 13-mode method has been employed for measuring exhaust gas emissions.

For thenew long-term control (since 2005), a new method based on the JE05 mode will be used.
This new method uses a conversion program to determine the engine revolution and torque according to
the driving mode (JE05) with which an engine is operated. This conversion is calculated from transmission
gear position which is set based on a certain rule as well as engine and vehicle specific parameters, so that thedifferences in revolution and torque among engines are reflected properly.
Assuming that exhaust gas emissions performance is evaluated appropriately, specifications (technical data)needed for the conversion have been standardized for each of gross vehicle weight categories and load
categories in consideration of the fact that a single engine type is used for a large number of different vehicle
types and in consideration of reducing burden for the manufacturers. The registration statuses (actual sales)of each category of vehicles are also a factor for determining the standardized specification (technical data)(which means that the standardized technical data are determined from weight-averaged actual data by thesales (registration) number of each category of vehicles).

1.

Fuel efficiency measuring method
The following methods are considered to be available for heavy vehicles (See Table 1).
1]

Vehicle-based actual measurement

2]

Engine-based actual measurement(i)Using the standardized specification (technical data) of vehicle(ii) Using the actual specification (technical data) of vehicle
3]

Stand-alone engine actual measurement with the assumed vehicle body

4]

Simulation method (See Table 2 and Attachment 1)
Of these methods, Methods 1] and 3] are impractical, since a large number of different vehicle
types may require the manufacturers to spend large resources (time, labor and money) for
constructing the testing facility and performing measurements.
Method 2](i) (using standardized technical data including those for transmission) has been used8

for exhaust gas emissions measurement.

However, for reason that the difference between thestandardized data and the actual data may cause the evaluation to include larger errors than
exhaust gas emissions evaluation, this method is also inappropriate (more detailed
standardization would lead to the same problem as Method 2](ii) described next).

Method 2](ii) is impractical for the same reason as for Methods 1] and 3]. Method 2] may produce somelarge measurement errors, since many of engine dynamometers currently possessed bymanufacturers cannot control the torque within the torque range below zero, which cannot help
but assume the fuel consumption is zero though some consumption occurs during actual driving.
Method 4] does not need additional testing facilities, and does not take long time formeasurement though some work for preparing fuel efficiency maps occurs.

Fuel efficiency

maps may ease fuel consumption measurements even when performing them in multiple driving
modes. The measurement errors are significantly smaller than those of vehicle-based actual
measurement. This method can evaluate the effect of other factors than the engine, e.g.
transmission, on the fuel efficiency.
Method 4], simulation, is more advantageous than other methods in terms of various factors
such as testing facilities, labor and time resources, measuring accuracy, and factor-by-factor
analysis.

Therefore, this method shall be used in the evaluation.

9

Table 1

Heavy Vehicle Fuel Efficiency Measuring Methods

10Simulation Method Overview○Convert the drive modeindicated in a speed vs. time
into an engine operating modeindicated in an engine
revolution/torque vs. time.

Speed

Table 2

Driving Mode
Conversion programTime-Determine gear-shift positions.
-Calculate engine revolution andtorque.

Specs (technical data)of a vehicle

Input

Engine operation mode

○With the use of a computer,
calculate fuel efficiency based on
the engine operating mode andfuel efficiency maps.

Engine revolution

Fuel efficiency map

Engine torque

Vehicle weight, running resistance,
rated revolution, idling revolution,
full load torque, etc.

By means of inputting data (vehicle
specs, driving resistance, and engine
specs of a vehicle to be measured),
the gear shift position for each time
unit is determined. Along with it,
the engine revolution and torque foreach time unit are also determined.

Time

Computingend

Fuel
consumption =∑ F .C ( i )i = start

Before simulation, perform operation
tests to create a fuel efficiency mapthat describes the relationshipbetween engine revolution/torqueand fuel consumption.

Fuel consumption

Fuel efficiency

Source: Japan Automobile Research Institute: Survey Report on Evaluation Methods for Heavy Vehicles, March 2003

11

2.

Drive modes
Many of heavy vehicles are used mainly for interurban travel (high-speed drive). To simulate actual

usage as accurate as possible, fuel efficiency evaluations shall use a combined mode of urban drive andinterurban drive modes based on the proportion of usage.
1]

Urban drive mode
The exhaust gas emissions control (the new long-term control), effective since 2005, requires vehicles

having a gross vehicle weight of greater than 3.5 tons to be tested in JE05 mode (a transient driving
mode defined based on urban drive statistics). Therefore, fuel efficiency evaluations shall use the same
principle of the driving mode.
Table 3

Urban Drive Mode

Vehicle speed (km/h)

1002]車速Interurban(km/h) drive mode
80
Considering
the survey results on the interurban expressway network and actual driving situation, the60following
40 conditions shall be applied to the interurban drive mode (See Attachment 2).
1) 20Travel speed0
From
the fact that changing speed during high-speed travel does not much affect the fuel0800constant.
1000 Taking
1200the survey
1400 result
1600
1800driving
2000
consumption,200
the speed400
shall be600
consideredon actualTime(s)
時間 (s)
situation into consideration, a single speed of 80 km/h shall be applied irrespective of vehicle types.
2]

Interurban drive mode
Considering survey results on the interurban highway network and actual driving situation, thefollowing conditions shall be applied to the interurban drive mode (See Attachment 2).
1)

Travel Speed
From the facts that speed change during high-speed travel does not much affect the fuelconsumption, the speed shall be considered constant. Taking the survey result on actual driving
situation into consideration, a single speed of 80 km/h shall be applied irrespective of vehicle types.
2)

Longitudinal grade
Longitudinal grades greatly affect fuel efficiency. The grade distribution along of Tomei

Expressway, an interurban expressway having the largest traffic throughout the country, shall be
used as a representative road profile for simulation (See Table 4).
3)

Load (riding) ratio
Based on survey results on actual driving situation and specified conditions for exhaust gas

emissions measurement, the load ratio shall be 50% irrespective of vehicle types.

12

Table 4Longitudinal Grade %3]Interurban Drive Mode

6
4
2
0
-2
-4
-6
0

500

1000

1500
Time (s) s
時間

2000

2500

3000

3] Proportion of the two modes
Based on survey results on actual driving situation and frequency of expressway use, the proportionof the urban and interurban drive modes shall be determined for each vehicle type as follows (GVW =Gross Vehicle Weight) (See Attachment 2).
Table

Proportion of the Urban and Interurban Drive Modes
Passenger vehicles

Freight vehicles(11 persons or more)
Vehicle type
GVW

Ordinary bus

Route bus

Other than tractor

Tractor

14 tons orOver

20 tons orOver

20 tons or

Over

less

14 tons

less

20 tons

less

20 tons

0.9

0.65

1.0

0.9

0.7

0.8

0.9

0.1

0.35

0.0

0.1

0.3

0.2

0.1

Drive proportion
Upper: Urban mode
Lower: Interurban
mode

13

3.

Other notes(1)

AT and AMT vehicles

1] AT vehicle (equipped with torque converter)
The conversion program for the simulation method is intended for MT (manual transmission)
vehicles.

Similar programs (algorithms) for AT (automatic transmission) vehicles do not exist.

There is no universal design of simulation method available for evaluating fuel efficiency applicable
regardless of transmission types is available.

Therefore, an alternative method shall be developed.

Normally, AT vehicles have worse fuel efficiency than MT vehicles. According to some test data,comparing an AT vehicle with a MT vehicle having the same number of gears and gear ratios, theformer has a fuel efficiency ratio of about average 0.9 compared to the latter (specifically 0.91 for
Urban drive mode and 0.96 for Interurban drive mode).

Therefore, as a temporary method,

calculate the fuel efficiency value of an MT vehicle which has the same number of gears and gear
ratios as the AT vehicle under test, and then multiply it by the abovementioned fuel efficiency factor
between AT and MT vehicles.
2]

AMT (automated manual transmission) vehicle
AMT vehicles differ from manufacturer to manufacturer in terms of the transmission logic applied.
However, they are approximately the same as the transmission logic by “excess drive force approach”
in the fuel efficiency simulation method; and the fuel efficiency is not much different among them.
Therefore, the fuel efficiency value of AMT vehicles shall be calculated assuming them as ordinary
MT vehicles.

(2)

Vehicles equipped with a post treatment device with forced regeneration control
Vehicles equipped with a post treatment device such as continuous regenerative DPF (diesel particle

filter) have a different engine control that cannot be covered by the normal operation fuel efficiency map,since their operation includes activating the catalyst by injecting fuel, burning the particles on thesurface of the filter, and regenerating the catalyst that has been stained with sulfur.

And, the fuelconsumption may increase compared to vehicles without such devices.
In this case, calculate the difference (change rate) in fuel efficiency between vehicles with and without
the forced regeneration control, and then multiply fuel efficiency calculated using the fuel efficiency
map for normal operation by the change rate to determine the fuel efficiency value of the vehicles.
4.

Energy consumption efficiency (fuel efficiency) equation
Energy consumption efficiency (fuel efficiency) shall be calculated using the following equation.
E=1 /{αu/Eu + αh/Eh}
Where,
E: Energy consumption efficiency (fuel efficiency) (km/l)

Eu: Urban drive mode energy consumption efficiency (fuel efficiency) (km/l)

Eh: Interurban drive mode energy consumption efficiency (fuel efficiency) (km/l)

αu : Proportion of urban drive
αh : Proportion of interurban drive14

(Annex 1)

Simulation Method

This method converts a given drive mode (travel speed vs. time) into an engine operating mode (engine
revolution & torque vs. time) by inputting the specs (technical data) of a vehicle into a conversion program,and then calculates fuel efficiency under the drive mode using an actual-measurement based fuel efficiency
map (representing the relationship between the engine revolution-torque combination and fuel efficiency
for each engine).
(1) Conversion program
The conversion program intended for exhaust gas emissions evaluation (per Notice No. 2002-619 of
the Ministry of Land, Infrastructure and Transport; see Attachment 41), as it is, shall be used for fuelefficiency evaluation.
FigureConversion Program Overview

Speed

Drive mode
走行モード

入力車両諸元The specs (technicaldata) of a vehicle

速度

Enginerelated parameters
エンジンに関する諸元-・全負荷エンジントルク
Full load engine torque-・アイドリングエンジン
Idling engine revolution
回転数-・最高出力エンジン回転数
Maximum output engine revolution- Maximum engine revolution with load
・有負荷最高エンジン回転数

時間

Time

Conversion
program *変換プログラム※
Determine
the shift lever
シフト位置を決定
position

Drivetrain
related parameters
動力伝達系に関する諸元-・変速機ギヤ段数
Number of transmission gears-・変速機ギヤ比
Transmission gear ratios-・終減速機ギヤ比
Final reduction gear ratio- Tire dynamic load radius・タイヤ動的負荷半径. Engine torque

Driving
resistance parameters
走行抵抗に関する諸元Engineoperatingmode
による運転モード
エンジン
・エンジン回転数- Engine
revolution
・エンジントルク
torque- Engine. Engine revolutionエ

エン数- Rolling resistance coefficient (vehicle weight for testing)-・ころがり抵抗係数（試験時車両重量
Air resistance coefficient x front projection area )(full height x full width)
・空気抵抗係数×前面投影面積（全高・全幅）

Vehicleweight related parameters
車両重量に関する諸元-・空車時車両質量
Complete vehicle kerb mass
-・最大積載量
Maximum load
-・乗車定員Riding capacity

時間
Time

* Conversion program - algorithm
The following hypotheses regarding driver’s operating behaviors are used for determining theposition of the shift lever.
1] To accelerate, the driver moves the shift lever from lower to upper positions.
2] The driver selects an appropriate gear depending on the vehicle kerb mass, vehicle speed,
acceleration, engine torque and revolution.
3] When changing gears, the driver may skip the next gear depending on mode type, vehicle kerb
mass, engine performance, and gear ratios.
4] Ensure the follow-up characteristics of vehicle speed mode.
5] Once a gear position is changed, it is kept unchanged for the specified period (3 seconds; to avoid
unnecessarily frequent shifting operation).
6] To accelerate from a slow speed or constant speed travel, the driver may shift gears to a lower
position, if necessary.
7] To decelerate, the driver uses the brake, but does not shift the lever to a lower position, unless it’s

15

necessary.
(2)

Specs (technical data) of vehicles

To measure fuel efficiency using the simulation method, the conversion program uses the following
vehicle parameters.
Table

Specification Setting - Overview

Parameter

Parameter setting

Full load engine torqueEngine friction toque
Idling engine revolution
Maximum output engine revolution
Maximum engine revolution (withload)

1] Engine

Number of transmission gears
Transmission gear ratios

2] Drivetrain

For each engine
type;
For eachtransmission typeRolling resistanceFor each fuelefficiency
category applied
to allmanufacturers.

3] Driving
Air resistanceComplete vehicle kerb weight4] Vehicle’s bodyform

For eachtransmission type

Final reduction gear ratio

Tire dynamic load radius

resistanceFor each engine
type

Maximum load
Riding capacity
Full height
Full width

For each fuelefficiency
category applied
to allmanufacturers.

Actual value

Actual value* Fuel efficiency evaluation is required
for each model of transmission systemapplied for certification(Average) actual value* The final reduction gear ratio and tire
dynamic load radius should be thosehaving an actual V1000 value closest to
the highest gear V1000 value
calculated as an arithmetic mean of all
registered (applied for certification)
vehicles within the same engine andtransmission model.
Standard values (note 1)* Unified value (*) for each fuelefficiency category available for all
manufacturers.
(*) This value can be calculated byentering the standard values of 4]
shown below in the equation (note 2).
Standard values (note 1)* Unified value for each fuel efficiency
category
availableforallmanufacturers.
This value is astandard plain body value, taking theregistration (selling) situation into
consideration.

(Note 1) Parameters for driving resistance and vehicle form
Heavy vehicles vary widely in terms of various features including the vehicle form. Moreover, there is no establishedmethod for evaluating the driving resistance individually based on their actual specifications. Therefore, a standard form
(plain body) has been defined for each of fuel efficiency categories. The driving resistance common for all
manufacturers shall be used.
(Note 2) Driving resistance approximation
The following equation has been used for exhaust gas emissions evaluations (the rolling resistance coefficient is a
primary approximation determined with the vehicle kerb weight for testing; and the air resistance coefficient is a primary
approximation determined with a function of [full height x full width] (front projection area)). This equation is used todetermine driving resistance.
17 .6
μ r = 0.00513 +W
μ a A = 0.00299 B ⋅ H − 0.000832
μr: rolling resistance coefficient

μa: air resistance coefficient

16

Ａ: front projection area

Ｗ: vehicle kerb weight for testing
Ｂ: full width
Ｈ: full height* The vehicle kerb weight for testing is calculated as follows.
・Truck and tractor: Complete vehicle kerb weight + Maximum load/2 + 55 (human body weight of one person)
・Bus: Complete vehicle kerb weight + Riding capacity (number of passengers) x 55 (human body weight of one
person)/2* For the air resistance coefficient for bus, the above approximation is multiplied by a correction factor (0.680).

(3)

Engine fuel efficiency map
The engine fuel efficiency map shows a relationship between the engine’s revolution-torque andfuel consumption.

The map shall be created for each model of engines.

For each combination of the engine’s revolution (at least 6 points in the range between the lowest
and highest revolutions) and torque (at least 5 points in the range between zero and full load torque),measure the instantaneous value of fuel consumption.

Using an interpolation technique with thevalues at other given revolution-torque combinations, a fuel efficiency map can be created.
FigureEngine Fuel Efficiency Map – How to Create

For each combination of the engine’s revolution (at least 6 points) and torque(at least 5 points), measure the instantaneous value of fuel consumption; andcreate a fuel efficiency map.

1000

1000
800

N-m

400

Engine torqueエンジントルク

Enginetorqueエンジントルク

N-m

800
600

200

0

0.012
0.01
0.008

600

0.006

400

0.004
200
0.002
0

F.C (L/s)
0

-200
0

500

1000
1500
2000
rpm
エンジン回転数
Engine revolution

2500

3000

-200
500

Actual measurement of instantaneous
fuel consumption (liter/s)

17

1000

0

1500
2000
2500
エンジン回転数rpm
Engine revolution

3000

(4)

Accuracy of the simulation method

To evaluate the accuracy of the simulation method, a comparison was made between a fuel efficiency
estimated by using “fuel efficiency map” based on the simulation method and that obtained by thevehicle-based actual measurement (*).
To enable effective comparison, these two measurements were made by using the same vehicle speed
and shift lever position; and the fuel efficiencies of them are compared.
(*) Based on the report of “the Survey on Heavy Vehicle Fuel Efficiency Evaluation Method”, agovernmental project under the Ministry of Land, Infrastructure and Transport (Japan Automobile
Research Institute, March 2003)
1]

How to evaluate the accuracyFirst, measure the actual fuel consumption using the vehicle-based actual measurement method.
Next, obtain the engine revolution and torque that correspond to the vehicle speed and shift lever
position at the actual measurement.

Then, with the engine revolution and torque, the fuelconsumption was estimated from an engine fuel efficiency map.

The map should be created based on

the engine removed from the vehicle which was used in the vehicle-based actual measurement.
Finally, compare the fuel efficiency obtained from the simulation method with that obtained from theactual measurement.

Figure 1 shows the steps of the comparison.

Simulation method
Vehicle-based actual measurement

Shift lever position Vehicle speed

Engine revolution and torque

Fuel efficiency map

Measure using the chassis dynamometer

Instantaneous fuel consumption
Fuel efficiency
Figure 1

CompareFuel efficiency measured by the vehicle-based
actual measurement method

Steps to Evaluate the Accuracy of the Simulation Method

18

Engine revolution and torque were calculated using the following equation with the actual measurements ofvehicle speed and shift lever position.
・ Engine revolution
1000 im ⋅ i f
⋅
⋅V
Ne =
120π
r
Engine revolution
Where
N e : engine revolution
V : vehicle speedrpm

km / him : transmission gear ratio
i f : final reduction gear ratior : tire dynamic load radiusm・ Engine torque
R≥0
M=

r

ηmη f imi f

⋅R

R<0
M=

r ⋅ηmη f
imi f⋅RHowever
R = μrW +sα
W + μa AV 2 + (W + ΔW1 + ΔW2 )g100

Where,
M : engine torque N − m
R : driving resistance N

ηm : mechanical transmission efficiency of the transmission gearη f : mechanical transmission efficiency of the final reduction gearμr : rolling resistance coefficient N / N
N / m2 /(km / h)μa : air resistance coefficients

2: longitudinal grade %A : front projection aream2

W : vehicle kerb weight for testingN

ΔW1 : equivalent weight of the rotating parts such as an engine and flywheel N
ΔW2 : equivalent weight of the rotating parts other than the engine

α : vehicle acceleration

m/ s

N

2

g : acceleration by gravity

The equivalent weight of the rotating parts (such as the gears and tires) and the mechanicaltransmission efficiency are as follows according to other studies.
・ Equivalent weight of rotating parts = (0.07 + 0.03 x transmission gear ratio2) x vehicle kerb weight
Note: the weight of the portion from the transmission output axle to tire is 7% of the vehicle
kerb weight; and the portion from the engine to transmission gear input axle is 3% of thevehicle kerb weight.
・ Mechanical transmission efficiency
98% for gears directly coupled to the transmission; 95% for other types of transmissions
95% for final reduction gear

19

2]

Results
With the values of 4 different heavy vehicles shown in Table 1, a comparison study between the fuelefficiency by the vehicle-based actual measurement and the estimated fuel efficiency by the simulation
was conducted.

As shown in Figure 2, the error by the simulation to the actual measurement is foundto be limited to about 0.4% irrespective of the types of heavy vehicles.

Body

Table 1

Vehicles Under Test: Specifications

Vehicle under test
Overall length, mm
Full width, mm
Full height, mm
Vehicle kerb weight, kg
Riding capacity, person
Maximum load, kg
Gross vehicle weight, kg
Engine under test

A
4690
1695
1990
2140
2
2000
4250
a
In-line4-cylinder
DI, NA
18.4
4104
125/3200
29.5/2000
5.339
2.792
1.593
1.000
0.788
4.625

Type
Compression ratio
Total swept volume, cc
Maximum output, PS/rpm
Maximum torque, kgm/rpm
1st gear
2nd gear
3rd gear
4th gear
5th gear
6th gear
Final reduction ratio

Transmission
gear ratio

Transmission

EngineNumber of cylinders, and their configuration

B
11990
2490
2950
8590
3
11250
19950
b
V-type8-cylinder
DI, NA
17.3
21205
400/2200
142/1400
6.326
4.139
2.326
1.480
1.000
0.731
5.571

C
8490
2260
2500
3770
2
3750
7630
c
In-line6-cylinder
DI, TI
17.5
7127
220/2700
66.0/1700
6.120
3.948
2.580
1.540
1.000
0.763
3.900

D
7890
2490
2800
6640
2
12000
18750
d
In-line6-cylinder
DI, TI
16.0
10520
300/2150
110/1100
6.523
4.159
2.700
1.625
1.000
0.692
5.250

Fuel efficiency by the simulation
method, km/l

10
y = 0.9956x
2
R = 0.9967

8
6

Vehicle Ａ
Vehicle Ｂ

4

Vehicle Ｃ
Vehicle Ｄ2
All vehicles

0

0

2

4

6

8

10

Fuel efficiency by the vehicle-based actual
measurement method, km/l

Figure 2

Accuracy of Fuel Efficiency Estimated by the Simulation Method(Comparison in fuel efficiency between by the vehicle-based actual measurement method and by thesimulation method)20

(Annex 2)

Interurban Drive Mode Settings(Sections 1 (1) and 2 are based on the report of “the Survey on Heavy Vehicle Fuel Efficiency Evaluation
Method”, a governmental project under the Ministry of Land, Infrastructure and Transport (Japan
Automobile Research Institute, March 2003); and sections 1(2), 3, 4 and 5 are based on the report of “theStudy on Standardizing Heavy Vehicle Fuel Efficiency Measuring Method and Survey on Heavy Vehicle
Fuel Efficiency Standards”, a governmental project under the same Ministry (Japan Automobile ResearchInstitute, March 2004)).
Travel speed settings(1)

Effect of travel speed fluctuation on fuel efficiency
Before determining the travel speed profile in the interurban drive mode, an experimental test using

five diesel engine driven trucks having a maximum load of 2 to 10 tons was made for investigating theeffect of the travel speed fluctuation on the fuel efficiency (these trucks were half loaded during thetest).
With respect to driving mode having a sinusoidal waveform (flat road) with average 80 km/h vehicle
speed, change the amplitude of speed fluctuation in the range of 0 to 10 km/h, and investigate the effect.
The result is shown in Figure 1.
about 5%.

The speed fluctuation of ±10 km/h worsens the fuel efficiency by

It implies that a large fluctuation in travel speed may affect the fuel efficiency.

However,many of drivers tend to keep the travel speed as constant as possible when driving on an expressway.
So, such fluctuation of as large as ±10 km/h is unlikely.

Smaller fluctuation in driving speed lessaffects the fuel efficiency.
As a result, the interurban drive mode shall use a constant travel speed, without any consideration to
speed fluctuation.

Speed km/h

100
90
80
70
60
0

45
Time (s)

22.5

67.5

90

1
Change in fuel efficiency

1.

0.99
A(GVW<20t)
B(GVW<20t)
C(GVW<16t)
D(GVW<8t)
E(PL≦2t)

0.98
0.97
0.96
0.95
0.94
0

2

4

6

8

10

Amplitude of drive speed km/h

Figure 1

Effect of Travel Speed Fluctuation on Fuel Efficiency

21

(2)

Setting travel speed (constant speed)
Before determining the travel speed (constant speed) in the interurban (expressway) drive mode, aninquiry was made for the owners of freight vehicles (trucks and tractors) with a gross vehicle weight(GVW) of 3.5 tons or larger and passenger vehicles (buses) having a riding capacity of 11 persons ormore to survey the actual expressway travel speed (see an attachment for further details of the inquiry).
The travel speed was determined in consideration of the inquiry results and other factors (exhaust gas
emissions measuring procedures, various regulations, etc.). (Following (3) and (4) are determined
likewise).
1]

Trucks1) Average and standard deviation
Figure 2 shows the average and standard deviation values of expressway travel speed for each of
GVW categories of “freight vehicles”.

Except tractors of less than GVW 20t that drive at less than

80 km/h, the vehicles in all other GVW categories fall in the travel speed range from 80 to 85 km/h.

100
80
60
40

Overall

Tractor over 20000

Tractor up to 20000

20001-25000

16001-20000

14001-16000

12001-14000

10001-12000

8001-10000

7501-8000

Over 3 tons

3 tons or less0

2 tons or less

20
Load 1.5 tons or lessExpressway cruising speed(km/h)

Truck and tractor

GVW (kg)

Figure 2

Expressway Travel speed of Trucks by GVW Category(Average and Standard Deviation)2) Setting travel speed
The Road Traffic Act specifies the maximum travel speed of expressway as follows.
GVW of 8 tons or larger, or maximum load of 5 tons or larger

80km/hOther than the above

100km/hExcept tractors of less than GVW 20 tons, the average value of travel speed falls in the range of
80 to 85 km/h irrespective of GVW categories.

Therefore, in consideration of the inquiry resultand legal requirement for the maximum travel speed, it is reasonable to unify the travel speed to 80
km/h irrespective of GVW categories.
2]

Bus<Ordinary bus>
1) Average and standard deviation

22

Figure 3 shows the average and standard deviation values of expressway travel speed for each of
GVW categories of “ordinary bus.”

The driving speed falls in the range of 80 to 85 km/h

irrespective of GVW categories.

GVW (kg)

Figure 3(ordinary bus)
Overall

16001-20000kg

14001-16000kg

12001-14000kg

10001-12000kg

6001-8000kg

8001-10000kg

120
100
80
60
40
20
0
4001-6000kg

Expressway cruising speed(km/h)

Ordinary bus

Expressway Travel speed of Ordinary Buses by GVW Category(Average and Standard Deviation)2) Travel speed
The travel speed falls in the range of 80 to 85 km/h irrespective of GVW categories.
the speed shall be a single value common for all GVW categories.
driving speed include 80 km/h, 85 km/h and 90 km/h.

Therefore,

Possible candidates of the

However, in consideration of the legal

requirement for the maximum travel speed, it is reasonable to select 80 km/h also for ordinary bus
as well as for freight vehicles.
< Route bus>
As mentioned later (See 4.), it is assumed that this category of bus does not use expressways.
Therefore, the travel speed does not have to be specified.

23

2.

Setting longitudinal grade(1) Effect of longitudinal grade on fuel efficiency
As seen in expressways, interurban roadways are not always flat and have ascent and descent grades.
This survey clarified the effect of longitudinal grades on fuel efficiency assuming driving at constant
speed of 80 km/h.
The survey result is shown in Figure 4. A longitudinal grade of 1% worsens the fuel efficiency by
about 30%. Longitudinal grades affect fuel efficiency very much.

Change in fuel efficiency

1.2
1.1
A(GVW<20t)
B(GVW<20t)
C(GVW<16t)
D(GVW<8t)
E(PL≦2t)

1
0.9
0.8
0.7
0.6
-0.2

0

0.2

0.4

0.6

0.8

1

Grade (%)

Figure 4

Effect of Longitudinal Grades on Fuel Efficiency

Next survey was to find causes of the effect of longitudinal grade on fuel efficiency.
The driving routes used for this survey were round trips of 1/10-scale Tomei Expressway and1/10-scale Chuo Expressway (average 0% grade in both).

Figures 5 and 6 show the grade profile of theGrade %

Tomei and the Chuo Expressway respectively.
6
4
2
0
-2
-4
-6
0

500

1000

1500

2000

2500

3000

Grade %

Time (s)

8
6
4
2
0
-2
-4
-6
-8
0

Figure 5Longitudinal Grade Profile of Tomei Expressway

Figure 6

Longitudinal Grade Profile of Chuo Expressway

500

1000

1500

2000

Time (s)Figure 6

Longitudinal Grade Profile of Chuo Expressway

24

2500

3000

Figure 7 shows the fuel efficiency in the case of travel at constant speed of 90 km/h throughout the tworoutes.

As shown in these figures, the fuel efficiency worsens by more than 2% for driving on the Tomei

Expressway, and more than 5% for driving on the Chuo Expressway.
Flat

Chuo

Tomei

Fuel efficiency (Flat = 1)

1
0.98
0.96
0.94
0.92
0.9
0.88
0.86
A(GVW<20t)

Figure 7

B(GVW<20t) C(GVW<16t)
D(GVW<8t)
Vehicle type (maximum load)

E(PL≦2t)

Fuel Efficiency During Drive on Expressway

Figure 8 shows examples of actual travel speed measured.

With the presence of longitudinal grades,

the travel speed varies because it is difficult to maintain the specified speed.

Speed
速度 (km/h)
km/h

東名（半積載）Tomei expressway(half loaded)
92
90
88
86
84
82
80
0

500

1000

1500

Time時間
(s)

2000

2500

3000

2000

2500

3000

2000

2500

3000

2000

2500

3000

s

東名（定積載）Tomei expressway(full loaded)

速度

km/h

Speed (km/h)

92
90
88
86
84
82
80
0

500

1000

1500

Time時間(s) s
中央（半積載）Chuo expressway(half loaded)
92

速度

km/h

Speed (km/h)

90
88
86
84
82
80
0

500

1000

1500
時間 s
Time
(s)

中央(定積載）Chuo expressway(full loaded)

92

Speed
(km/h)
速度 km/h

90
88
86
84
82
80
0

500

1000

1500
時間 s
Time
(s)

(Note) Full loaded: 100% of the maximum load
Half loaded: 50% of the maximum load
Figure 8

Examples of Vehicle Speed and Follow-up Characteristics During Drive on Expressway

25

To determine whether the worse fuel efficiency is a direct result of longitudinal grades or caused by theunsteady travel speed due to the presence of grades, calculations of fuel efficiency for driving at actual(non-steady) speeds on a flat expressway are shown in Figure 9.
There is almost no difference in fuel efficiency between at steady speed and unsteady speed (about 0.5%
for fully loaded vehicle traveling on the Chuo expressway).

It implies that the worse fuel efficiency iscaused directly by the grades, not caused by the speed fluctuation.
90 km/h constantTomei (actual speed, flat)

Chuo (actual speed, flat)

Tomei (grades)

Chuo (grades)

Fuel efficiency ratio(90 km/h constant & falt = 1)

1
0.98
0.96
0.94
0.92
0.9
0.88
0.86

Half loaded

Figure 9

Full loaded

Causes of Worsen Fuel Efficiency

Therefore, the interurban driving mode shall include considerations on longitudinal grades of roads.
(2) Setting longitudinal grades
The grade profile of Tomei Expressway, accounting for the largest traffic ([number of vehicles] x km)
among those in Japan, shall be used as the specific grade profile for Interurban driving mode (see Figure
10).

Traffic volume ([number of vehicles] x
km/day)12,000,000
10,000,000
8,000,000

Tomei expressway
Chuo expressway
Tohoku expressway

6,000,000

Chugoku expressway

4,000,000

Sanyo expressway

2,000,0000Medium size

Large size

Very large size

Total

Figure 10 Traffic Volume of Major Expressways

26

3.

Loading (riding) ratio
To determine the loading (riding) ratio being associated with the interurban drive mode (expressway
drive mode), an inquiry was made for investigating the actual status of load (number of persons) ofheavy vehicles operating on expressways (see an attachment for further details of the inquiry).
1]

Truck
1) Average and standard deviation
Figure 11 shows the average and standard deviation values of the loading ratio of expressway
transport trucks by GVW category. Trucks having a larger GVW have a larger loading ratio. The
average value of loading ratio falls in the range of 40 to 60% irrespective of GVW categories.

Figure 11

Overall

Tractor over 20000

Tractor up to 20000

20001-25000

16001-20000

14001-16000

12001-14000

10001-12000

8001-10000

7501-8000

Over 3 tons

3 tons or less2 tons or less

120
100
80
60
40
20
0

Loading 1.5 tons or less

Loading ratio(%)

Truck and tractor

GVW (kg)

Truck Loading Ratio by GVW Category (Average and Standard Deviation)

1) Setting loading ratio
Exhaust gas emissions measurement use a loading ratio of 50%.
Although vehicles having a larger GVW have a larger loading ratio, its average value falls in therange of 40 to 60% irrespective of GVW categories, and the overall average is about 46%.
Therefore, taking the loading ratio at the exhaust gas emissions measurement into consideration, aloading ratio of 50% (half loaded) shall be used.

2]

Bus

<Ordinary bus>
1) Average and standard deviation
Figure 12 shows the average and standard deviation values of riding ratio of ordinary bus by
GVW category.

The average value of riding ratio falls in the range of 60 to 70% irrespective of

GVW categories.

27

Ordinary bus

80
60
40

GVW (kg)

Overall (ordinary bus)

16001-20000kg

10001-12000kg

8001-10000kg

6001-8000kg

4001-6000kg

014001-16000kg

2012001-14000kg

Riding Ratio (%)

100

Figure 12 Riding Ratio of Ordinary Bus by GVW Category(Average and Standard Deviation)2) Setting riding ratio
Exhaust gas emissions measurement/evaluations use a riding ratio of 50%.
The riding ratio falls in the range of 60 to 70% irrespective of GVW categories.
ratio shall be a single value common for all GVW categories.

Therefore, theThe average value for each of GVW

categories falls in the range of 60 to 70%, and the overall average of ordinary bus is about 66%.
Therefore, 65% is a possible candidate.

However, 50% is believed to be reasonable inconsideration of the fact that exhaust gas emissions measurement use this value, and that theloading factor for truck has been set to 50% as mentioned before.
<Route bus>
1) Average and standard deviation
Figure 13 shows the average and standard deviation values of riding ratio of route bus by GVW
category.

The average value of riding ratio of a GVW category of over 4t to below 6t is about

60%, while that of other GVW categories falls in the range of 30 to 40% (average of about 39%).

Route bus

80
60
40

16001-20000kg

Overall (ordinary bus)

GVW (kg)

14001-16000kg

12001-14000kg

10001-12000kg

8001-10000kg

06001-8000kg

204001-6000kg

Riding ratio (%)

100

Figure 13 Riding Ratio of Route bus by GVW Category (Average and Standard Deviation)282) Setting riding ratio
Exhaust gas emissions measurement use a riding ratio of 50%.
The riding ratio of a GVW category of 4 to 6 tons is higher than that of other GVW categories.
So, a possible option is to set 60% for the former category and 40% for the others.

However,

50% shall be used for route buses as well as ordinary buses, in consideration of the fact thatexhaust gas emissions measurement use this value.

29

4.

Setting the total proportion (of using expressways) in drive modes
To determine the total proportion (of using expressways) in the urban driving mode and interurban
driving mode, an inquiry was made for investigating the actual status of expressway usage (see anattachment for further details of the inquiry).
1]

Truck
1) Average and standard deviation
Figure 14 shows the average and standard deviation values of expressway usage ratio of trucks by
GVW category.

Trucks within a GVW category of over 20t to below 25t have an average

expressway usage of about 30%; for tractors within a GVW category of 20 tons or less, it is about
20%. Trucks and tractors within other GVW categories have an average expressway usage ofabout 10%.

Figure 14

Overall

Tractor over 20000

Tractor up to 20000

GVW (kg)

20001-25000

16001-20000

14001-16000

12001-14000

10001-12000

8001-10000

7501-8000

Over 3 tons

3 tons or less2 tons or less

100
80
60
40
20
0

Loading 1.5 tons or lessExpressway usage ratio (%)

Truck and tractor

Expressway Usage Ratio of Trucks by GVW Category(Average and Standard Deviation)2) Setting expressway usage ratio
Both Trucks within a GVW category of over 20t to below 25t and tractors within a GVW
category of 20 or less have higher expressway usage ratios.

Therefore, it shall be defined

separately for each of the four categories as shown below.
Truck:
Tractor:

2]

GVW of 20 tons or less10％

GVW of over 20 tons to below 25 tons

30％

GVW of 20 tons or less20％

GVW of over 20 tons

10％

Bus

<Ordinary bus>
1) Average and standard deviation
Figure 15 shows the average and standard deviation values of expressway usage ratio of ordinary
buses by GVW category. Though the average values vary widely depending on the GVW category,ordinary buses within a GVW category of 14 tons or less have an expressway usage ratio in the rangeof 10 to 30%; and those within a GVW category of over 14 tons have it in the range of 30 to 45%.

30

100
80
60
40

GVW (kg)

Figure 15

Average (ordinary bus)

16001-20000kg

14001-16000kg

12001-14000kg

8001-10000kg

6001-8000kg

010001-12000kg

204001-6000kg

Expressway usage ratio (%)

Ordinary bus

Expressway Usage Ratio of Ordinary Buses by GVW Category(Average and Standard Deviation)

2)

Setting expressway usage ratio
This value varies widely depending on GVW categories.

This suggests the possibility to define

the expressway usage ratio separately for each GVW category. However, in consideration of
distinctive difference in the usage ratio between two groups of GVW categories (14 tons or less &over 14 tons), the expressway usage ratio shall be defined separately for each of the two groups asshown below.
GVW of 14 tons or less:10％

GVW of over 14 tons:

35％<Route bus >1)

Average and standard deviation
Figure 16 shows the average and standard deviation values of the expressway usage ratio of routebuses by GVW category. The average value is less than 5% irrespective of GVW categories, with

Route bus
100
80
60
40

GVW (kg)

Figure 16

Expressway Usage Ratio of Route Bus by GVW Category(Average and Standard Deviation)

31

Overall (route bus)

16001-20000kg

14001-16000kg

12001-14000kg

8001-10000kg

6001-8000kg

010001-12000kg

204001-6000kg

Expressway usage ratio (%)

the maximum value of about 7% for GVW category of over 16t up to 20t.

2)

Setting expressway usage ratio
For all GVW categories, the expressway usage ratio is as small as several percents.

it shall be considered zero irrespective of GVW categories.

32

Therefore,(Attachment)
Questionnaire (Inquiry about Actual Driving Situation) - Overview
1]

Area: throughout Japan

2]

Target: trucks and buses of GVW 3.5 tons and above

3]

The extracted number of targets: 28,600 (truck) and 7,268 (bus)(For the numbers of targets by GVW category, see the next table.)

4]

Means to deliver the questionnaire: by postal mail5]

Respondents: vehicle operation manager

6]

Major question items: travel speed, loading weight, expressway usage ratio, etc.

7]

Period: October through November 2003

8]

Valid responses: 4,210 (14.7%) for truck and 2,006 (27.6%) for bus(For the numbers of valid responses by GVW category, see the next table.)

9]

Means to analyze the information collected:
・ Aggregate the collected information by categories as shown in the next tables. Route buses
and other buses (“ordinary bus”) were separately analyzed.

33

TableNumber of Extraction and of Valid Responses

Nationwide
population oftrucksResponses rateunit

28,600

4,210

14.7

4,049,247

Load≦1.5ｔ

3,705

504

13.6

279,806

Small truck

1.5ｔ＜Load≦2ｔ

6,719

845

12.6

1,636,450（3.5ｔ＜GVW≦7.5ｔ）

2ｔ＜Load≦3ｔ

2,885

402

13.9

272,5143ｔ＜Load

858

106

12.4

89,8577.5＜GVW≦8t

3,855

481

12.5

949,5128ｔ＜GVW≦10ｔ

473

89

18.8

30,76410ｔ＜GVW≦12ｔ

331

63

19.0

21,17512ｔ＜GVW≦14ｔ

820

147

17.9

45,26714ｔ＜GVW≦16ｔ

481

75

15.6

29,20716ｔ＜GVW≦20ｔ

4,221

633

15.0

424,578

20ｔ＜GVW≦25ｔ

2,955

615

20.8

177,154

GVW≦20ｔ

946

193

20.4

70,72720ｔ＜GVW

351

59

16.8

22,236

Responses rate％

Number of valid
responses

Overall trucks

Number of valid
responses

The extracted
number of targets(Trucks)

Medium andlarge truck（7.5ｔ＜GVW≦25ｔ）

Tractor[Classified bytractor head GVW]

Overall buses
4t＜GVW≦6t
6t＜GVW≦8t
8t＜GVW≦10t
10t＜GVW≦12t

Nationwide
population of
buses

The extracted numberof targets（Buses）

％

unit

7,268

2,006

27.6

215,509

2,762

711

25.7

94,556

1,377

343

24.9

16,580

1,292

396

30.7

23,442

475

163

34.3

7,642

12t＜GVW≦14t

296

87

29.4

20,03114t＜GVW≦16t

717

198

27.6

46,99816t＜GVW≦20t

347

107

30.8

6,221

20t＜GVW

2

1

50.0

39

34

Attachment 4

Classification of Heavy Vehicles

To define fuel efficiency categories, using the same categories as those for exhaust gas emissions
measurement permits manufacturers to evaluate fuel efficiency under the same conditions, which may leadto effective environmental protections and reduce burden to be born for the manufacturers.
Basically, the classifications for exhaust gas emissions evaluations (i.e. vehicle categories based on the
gross vehicle weight (GVW) and maximum load) shall be applied for fuel efficiency evaluations.
Specifically, each type of heavy vehicles mentioned in the following sections 1 and 2 should be categorizedby various factors considered to affect fuel efficiency (such as the vehicle structure, intended use,transmission type, GVW) and actual shipment volume.
1.

Freight vehicles(1) Classification by structure
Of the types of freight vehicles, tractors are different from others as they are intended to tow vehicles
such as trailers.

Because tractors have a distinct feature (towing) that other freight vehicles don’t, thebody strength of tractors is not the same as the others.

Therefore, tractors shall be grouped separatelyfrom other types of freight vehicles (“tractors” and “other than tractors”) for the purpose of fuelefficiency evaluation.
(2) Classification by transmission types (manual transmission (MT (AMT)) and other than manualtransmission (AT))
Most of relevant vehicles use an MT.

It is assumed that this trend will remain unchanged in future.

For the purpose of measuring fuel efficiency, AT vehicles and MT vehicles are addressed essentially thesame each other (to evaluate an AT vehicle, calculate fuel efficiency assuming that the vehicle as acorresponding MT vehicle with the same number of gears and gear ratios, and multiply it by a factor:
see Attachment 3).
Therefore, no classification has to be made between MT and AT vehicles.

Target standard values offuel efficiency shall be determined based on MT vehicles; and then, for AT vehicles, it is adjusted
according to the share of AT vehicles as opposed to the sales of MT vehicles in the target year (AT is acontributor for worsening the fuel efficiency).
(3) Classification by gross vehicle weight and maximum load
<Other than tractor>
These categories shall be defined so that fuel efficiency can be properly evaluated taking thedifference of GVW into consideration. Another point for defining these categories is that the ratio of
category range to the GVW shall not much vary each other.
<Tractor>
Tractor axle configurations are mainly 4x2 or 6x4. The 4x2 configuration is used mainly for35

tractor head GVW (= tractor mass + 5th-wheel load + riding capacity x 55 kg) of not greater than 20
tons, and 6x4 configuration is used mainly for tractor head GVW of greater than 20 ton． Therefore,
it is reasonable to define two categories by tractor head GVW: “20t or below” and “over 20t”.
As a result, freight vehicles are categorized as follows.
＜Other than tractor＞
NO

GVW range

Maximum load range

（t）

（t）

1
2

3.5<&≦7.5

3

NO(Tractor head)
GVW range（t）

≦1.5

1

≦20

1.5<&≦2

2

20<

2<&≦3

4

2.

＜Tractor＞

3<5

7.5<&≦8－

6

8<&≦10－710<&≦12－8

12<&≦14－914<&≦16－10

16<&≦20

－

11

20<

－

Passenger vehicles (riding capacity :11 persons or more)(1)

Classification by intended use
Buses used for public transportation service on a fixed route other than expressway and those forother use (ordinary bus) are quite different in terms of use and driving conditions.

Therefore, theyshould be separated as follows according to the classification defined by Article 22-3 (Seat belt etc.) of
the Road Vehicle Security Standard.
(i)Route bus
Of passenger vehicles having a riding capacity of 11 persons or more, limited those used foroffering regular public transport service on a fixed route other than expressways fall in thiscategory.

(ii) Ordinary bus
Besides passenger vehicles having a riding capacity of 11 persons or more, excluding those in the
category of “Route bus”, “small” and “light” passenger cars fall in this category.
(2)

Classification by transmission types (manual transmission (MT) and automatic transmission (AT))
Most of medium and large size relevant vehicles use an MT.

remain unchanged in future.

It is assumed that this trend will

Therefore, target standard values of fuel efficiency shall be determinedbased on MT vehicles; and then, for AT vehicles, it is adjusted according to the share of AT vehicles as
opposed to the sales of MT vehicles in the target year (AT vehicles are contributors for worsening fuelefficiency).
For small-size passenger cars, both MT and AT vehicles have large amount of shipment volume.

36

It

is assumed that this trend will remain unchanged in future.

For the purpose of measuring fuelefficiency, AT vehicles and MT vehicles are addressed essentially the same each other.

Therefore, as

well as for freight vehicles, no classification has to be made between MT and AT vehicles. And target
standard values of fuel efficiency shall be determined based on MT vehicles; and then, for AT vehicles,
it is adjusted according to the share of AT vehicles as opposed to the sales of MT vehicles in the target
year (AT is a contributor for worsening fuel efficiency).
(3)

Classification by gross vehicle weight and maximum loadThese categories shall be defined so that fuel efficiency can be properly evaluated taking thedifference of GVW into consideration. Another point for defining these categories is that the ratio of
category range to the GVW shall not much vary each other.
As a result, passenger vehicles (11 persons or more of riding capacity) are categorized as follows.
<Route bus ><Ordinary bus>NO

GVW range（ｔ）

NO

GVW range（ｔ）

1

6<&≦8

1

3.5<&≦62

8<&≦10

2

6<&≦8

3

10<&≦123

8<&≦10412<&≦14410<&≦125

14<

512<&≦146

14<&≦16

7

16<<Standard specification for each category>Standard parameter values for each of the vehicle categories defined in Sections 1 and 2 above (complete
vehicle kerb weight, maximum load, riding capacity, full height and full width: setting unified values foreach fuel efficiency category, which are common for all manufacturers, (which are also the standardized
values in consideration of actual sales (the number of registered units))) are as follows.

37

TableStandard Vehicle Specification<Freight Vehicle>(Other than tractor)
Category
NO
1
2
3
4
5
6
7
8
9
10
11

Standard parameters
Maximum load
range
（t）
≦1.5
1.5<&≦2
2<&≦3
3<
－
－
－
－
－
－
－

GVW range（t）

3.5<&≦7.5

7.5<&≦8
8<&≦1010<&≦1212<&≦1414<&≦1616<&≦20
20<

Complete vehicle
kerb weight
（kg）
1,957
2,356
2,652
2,979
3,543
3,659
4,048
4,516
5,533
8,688

Maximum
load
（kg）
1,490
2,000
2,995
3,749
4,275
5,789
7,483
7,992
8,900
11,0898,765

15,530Riding capacity(person)Full height（m）

Full width
（m）

3
3
3
3
2
2
2
2
2
2

1.982
2.099
2.041
2.363
2.454
2.625
2.541
2.572
2.745
3.049

1.695
1.751
1.729
2.161
2.235
2.239
2.350
2.379
2.480
2.490

2

2.934

2.490

(Tractor)
Category

Standard parameters

NO(Tractor head) GVW range（t）Complete vehicle
kerb weight（kg）

Maximum load（kg）

Riding capacity(person)Full height（m）

Full width
（m）

1

≦20

10,52524,000

2

2.927

2.490

2

20<

19,02840,000

2

2.890

2.490

38

<Passenger Car (11 persons or more)>(Route bus)
Category

Standard parameters
Complete vehicle kerb

Riding capacity

weight（kg）(person)

6<&≦8

5,186

2

8<&≦103NO

GVW range（t）

Full height（m）

Full width（m）

1

39

2.880

2.072

6,672

46

2.947

2.301

10<&≦12

7,324

62

2.949

2.304

4

12<&≦14

8,654

77

2.969

2.385

5

14<

9,790

79

2.962

2.490

Full height（m）

Full width（m）(Ordinary bus)
Category

Standard parameters
Complete vehicle kerb

Riding capacity

weight（kg）(person)3.5<&≦6

3,543

29

2.593

2.027

2

6<&≦8

5,622

29

3.019

2.197

3

8<&≦10

6,608

49

3.105

2.314

4

10<&≦12

8,022

58

3.160

2.399

5

12<&≦14

9,774

60

3.168

2.490

6

14<&≦16

12,110

62

3.320

2.490

7

16<

14,583

51

3.668

2.490

NO

GVW range（t）

139

Attachment 5

Target Standard Values for Heavy Vehicle

According to the Energy Conservation Law, the target standard values of fuel efficiency shall be
determined in consideration of possible improvements in fuel efficiency due to the subsequent technicaldevelopment, effect of the current or planned exhaust gas emissions regulations on the fuel efficiency, andfuel properties, while focusing on the most fuel-efficient vehicles in the current market.
1. Policy for determining the target standard values
Among all commercially available heavy vehicles in each category in 2002, select the vehicle that has
achieved the highest fuel efficiency as a basic.

Then, target standard values shall be determined basedon it, after evaluating fuel efficiency improvement due to technological development and effect ofworking around exhaust gas emission regulation on fuel efficiency within the period from 2002
(long-term control level) to 2015 (2009 exhaust gas emissions control level).

Note, because Low PM4☆ Approved Vehicles (*) have partially been on the market since FY 2004, their fuel efficiency levels
shall also be considered when determining the target standard value.
(*) Low PM4 ☆ Approved Vehicles: vehicles with lower PM emissions than the new short-term
control value by more than 85%.
2.

Technology improvements for fuel efficiency
Review the ongoing and planned R&D projects for improving the fuel efficiency of heavy vehicles,
and estimate which technologies will have been available and how much fuel efficiency will have been
improved by using such technologies as of the target year (2015).

These identified technologies andexpected improvement rate of fuel efficiency due to these technologies are shown below.
However, some of these new technologies may not be immediately available depending on the typesof heavy vehicles.

Expected diffusion rate of these technologies in future shall be taken into

consideration when determining the target standard values.
(1) Improvement of engine
1] Thermal efficiency can be improved by means of:
4-valve & center nozzles (1.0 to 1.5%), direct injection (4.0 to 5.0%), fuel injection at higher
pressure (200 MP equivalent) (2.0%), improved combustion chamber (0.5%), EGR (1.0 to 1.5%),
higher supercharging (BMEP = 2.0 MPa or higher) (2.5 to 4.5%), improved supercharging
efficiency (0.3 to 0.5%), variable supercharger (0.5%), intercooler (1.5 to 2.5%), turbo compound(0 to 1.5%), optimized entire engine control system (3.0%), etc.
2] Loss can be reduced by means of:Lower friction (1.0 to 1.5%), lower idling revolution (0.5%) and lower loss of auxiliary equipment
driving power (0.5 to 1.0%).

40

(2) Optimization of operating range of engine by means of:Larger number of transmission gears (1.0 to 5.0%), tor-con (torque converter) AT (-9.0 to -4.0%),
differential gear having a lower gear ratio (0.5 to 3.0%), direct coupling of the highest gear (0.5 to
3.0%)(3) Others
Idling-stop (0 to 4.0%)

3.

Evaluation of effect on fuel efficiency by working around exhaust gas emissions regulations
As for diesel engine driven heavy vehicles, estimate and evaluate adverse effects on fuel efficiency
along with the introduction of technologies addressing exhaust gas emission, which is intended to reduce
NOx and PM emission as well as which is necessary to comply with the 2009 exhaust gas emission
regulation slated to take effect in 2009 or 2010.

Specifically, the following exhaust gas emissions

reduction technologies (and corresponding deterioration rates) have been taken into consideration.
(1) PM reduction technologies(▲ 2 to 3%)
1] Engine
Improved fuel injection system (higher injection pressure, etc.), and improved combustion
chamber and intake system
2] Exhaust gas treatment technologies
Continuous regenerative DPF(2)

NOx reduction technologies (▲ 5 to 7%)

1] Engine
Improved EGR system (cooling and larger capacity), and improved fuel injection system (finer
control of injection rate, etc.)
2] Exhaust gas treatment technologies
Occlusion type NOx reduction catalyst (LNT) and Urea-additive NOx reduction catalyst (SCR)

4.

Effect of fuel properties on fuel efficiency
In the evaluation of improved fuel efficiency due to technological development and adverse effect onfuel efficiency due to exhaust gas emission regulations, it is supposed that the vehicles use commerciallyavailable diesel fuel containing sulfur of not greater than 10 ppm.

5.

Setting target standard values of fuel efficiency
Based on the sections 1 through 4 above, the FY 2015 target standard values shall be defined asfollows.

41

○Freight vehicle<Other than tractor>
Category

GVW range (t)Maximum load range (t)Target standard values (km/l)

≦1.5

10.83

1.5<&≦2

10.35

2<&≦3

9.51

3<

8.12

1
2

3.5<&≦7.5

3
4
5

7.5<&≦8

－

7.24

6

8<&≦10－6.52

710<&≦12

－

6.00

8

12<&≦14

－

5.69

9

14<&≦16

－

4.97

10

16<&≦20

－

4.15

11

20<

－

4.04

<Tractor>
Category

GVW range (t)Target standard values (km/l)

1

≦20

3.09

2

20<

2.01

○Passenger vehicles (riding capacity of 11 persons or more )<Route bus >Target standard values of fuelCategory

GVW range (t)

1

6<&≦8

6.97

2

8<&≦106.30

310<&≦125.77

412<&≦14

5.14

5

14<

4.23

Category

GVW range (t)Target standard values (km/l)

1

3.5<&≦6

9.04

2

6<&≦8

6.52

3

8<&≦106.37

410<&≦125.70

512<&≦145.21

614<&≦16

4.06

7

16<

3.57

efficiency (km/l)<Ordinary bus>

42

<For information only>
With the target standard values given as above, assuming that the shipment rate of vehicles per category
is the same in both FY2002 and the target year (FY2015), the fuel efficiency improvement rates (fuelefficiency weight-averaged by the shipment volume) when compared actual values in FY2002 to estimatedvalues in FY2005 are shown in the following tables.
○Freight vehicle
Fuel efficiency

2002 actual

2015 estimated

Other than tractor

6.56(km/l)

7.36(km/l)

12.2％

Tractor2.67(km/l)

2.93(km/l)

9.7％

Total

6.32(km/l)

7.09(km/l)

12.2％

improvement rate

○Passenger vehicles (riding capacity of 11 persons or more )Fuel efficiency

2002 actual

2015 estimatedRoute bus

4.51(km/l)

5.01(km/l)

11.1％

Ordinary bus

6.19(km/l)

6.98(km/l)

12.8％

Total

5.62(km/l)

6.30(km/l)

12.1％

43

improvement rate(For information only) Actual fuel efficiency of heavy vehicles shipped in FY2002, and target standard
values of fuel efficiency(1)

Freight vehicle (other than tractor (GVW 3.5 to 7.5 tons))
11.0

Fuel efficiency (km/l)

10.0
9.0
8.0
7.0
Target standard values

6.0
5.0

(2)

◆ Fuel efficiency

Load≦1.5t

1.5t<Load≦2t2t<Load≦3t

3t<LoadFreight vehicle (other than tractor (GVW 7.5 to 16 tons))

8.0
7.0

Fuel efficiency (km/l)

6.0
5.0
4.0
3.0
2.0

Target standard values◆ Fuel efficiency

7.5t＜GVW≦8t

8t＜GVW≦10t

10t＜GVW≦12t

44

12t＜GVW≦14t

14t＜GVW≦16t

(3) Freight vehicle (other than tractor (GVW over 16 tons) and tractor)
5.0

Other than tractor

TractorFuel efficiency (km/l)

4.0

3.0

2.0

Target standard values◆ Fuel efficiency

1.0
20t<GVW

16t<GVW≦20t

GVW≦20t

20t<GVW(4) Passenger vehicles (riding capacity of 11 persons or more ) (Route bus )8.0

Fuel efficiency (km/l)

7.0

6.0

5.0

4.0

3.0

Target standard values◆ Fuel efficiency

6t＜GVW≦8t

8t＜GVW≦10t 10t＜GVW≦12t 12t＜GVW≦14t 14t＜GVW

45

(5) Passenger vehicle (riding capacity of 11 persons or more ) (Ordinary bus)
10.0
Target standard values◆ Fuel efficiency

Fuel efficiency (km/l)

9.0
8.0
7.0
6.0
5.0
4.0
3.0

8t＜
10t＜
12t＜
14t＜
3.5t＜
4.5t＜
6t＜
GVW≦4.5t GVW≦6t GVW≦8t GVW≦10t GVW≦12t GVW≦14t GVW≦16t 16t＜GVW(Note) The target standard values shown above have been determined based on MT vehicles only. As for
AT vehicles, these values are adjusted with fuel efficiency lowering factors in consideration ofpenetration of AT vehicles in the target year.

Ordinary buses of 4.5t<GVW≦6t and 6t<GVW≦8t

have lower target standard values than the 2002 Top Runner values (MT vehicle) since thepenetration of AT vehicles is greater than those of other categories.

46

Attachment 6

Display Items

1.

Items to be displayed(1)

Display items
Like other designated equipment under the Energy Conservation Law, the following items shall be
displayed.
a. Vehicle name and typeb. Type, total displacement, maximum power and maximum torque of engine
c. Vehicle kerb weightd. Transmission type, number of gears, and gear ratios
e. Fuel supply equipment typef. Major measures for improving fuel efficiency
g. Energy consumption efficiency (fuel efficiency) (unit: km/l)
h. Manufacturer’ name(2)

Display of fuel efficiency

1] Types of the fuel efficiency to be displayed.
As the item g. above, the heavy vehicle mode fuel efficiency shall be displayed.
* Heavy vehicle mode fuel efficiency (see Attachment 3)
This is a weight-averaged value of the fuel efficiency for driving in the urban drive (JE05)
mode (Urban drive mode fuel efficiency) and that for driving in the interurban drive (“80 km/h
constant speed & representative grade distribution”) mode (Interurban drive mode fuelefficiency), by the factor set for each vehicle type in the following table.
Table Proportion of Drive Mode
Passenger vehicles (riding capacity

Freight vehiclesof 11persons or more )Vehicle type

Ordinary bus

Route bus

Other than tractor

Tractor

14 tonsOver

20 tons

Over 20

20 tons orOveror less

14tonsor less

tons

less

20tonsUpper: urban mode

0.9

0.65

1.0

0.9

0.7

0.8

0.9

Lower: interurban mode

0.1

0.35

0.0

0.1

0.3

0.2

0.1

GVW ragne
Drive proportion2] Additional information to be displayed along with the fuel efficiency
1) Driving resistance
The fuel efficiency measuring method (simulation method) uses a unified driving resistance ofa representative form (plain body) for each of fuel efficiency category, as a common “standard
specification” for all manufacturers.

Note: the driving resistance is one of the vehicle

47

parameters needed for determining the engine revolution and torque in a conversion program.
Therefore, to prevent the consumers from misunderstanding the real meaning of the displayed
value of fuel efficiency, its indication shall e.g. accompany a note “this fuel efficiency value wascomputed using the driving resistance of a standard form of vehicle body (plain body defined bycomplete vehicle kerb weight of X kg, maximum load of X kg (or riding capacity of X persons),
full height of X m and full width of X m).”2) Final reduction gear ratio and tire dynamic load radiusThis fuel efficiency measuring method (simulation method) uses a final reduction gear ratio
and tire dynamic load radius both of which have an actual V1000 value closest to the highest
stage V1000 value calculated as an arithmetic mean of all vehicles (those filed for certification)that use the same engine and transmission.
Therefore, the indication of fuel efficiency shall e.g. accompany a note “this fuel efficiency is
in case of the final reduction gear ratio of X and tire dynamic load radius of X m.”

2.

Compliance items
Like other designated equipment under the Energy Conservation Law, the following requirements
shall be satisfied.
1] The display items specified by Section 1(1) above shall be indicated in the catalogs of the relevant
heavy vehicles.

In this case, the item g shall be indicated in such a manner that it stands out e.g.

by underlining, using a large typeface, or changing the color of the characters.
2] To exhibit a heavy vehicle, all the items specified by Section 1(1) above shall be displayed clearlyin an easy-to-see place.

3.

Others
Vehicles under the category of “heavy vehicle” vary in terms of gross vehicle weight.

Moreover, theirintended use varies widely from “mainly for urban drive” to “mainly for expressway drive.”
Therefore, to ensure that consumers are given more effective information, in addition to the heavy
vehicle mode fuel efficiency, the following two types of fuel efficiency values may be displayed.
1) City drive mode fuel efficiency
This is the fuel efficiency in city drive mode (hereafter referred to as “city drive mode”), a typeof modes defined in JEO5 referred as urban drive mode.
2)Interurban drive mode fuel efficiency
This is the fuel efficiency in a drive mode with constant speed of 80 km/h (on an expressway
having a representative grade distribution), which is defined as interurban dive mode.
(Note) The target standard values are based on the “heavy vehicle mode fuel efficiency”.

48

Therefore,judgment on whether the target standards are achieved or not shall be evaluated with the weightaverages of “heavy vehicle mode fuel efficiency” for each manufacturer and for each category (theabovementioned two optional fuel efficiency values will not be used for this evaluation).

49

Attachment 7

Heavy Vehicle Fuel Efficiency Standard Evaluation Group,
Heavy Vehicle Standards Evaluation Subcommittee,
Energy Efficiency Standards Subcommittee of the Advisory Committee for Natural Resources and Energy
History of Holding

1st Joint Meeting (September 2, 2004)
・ Possibility of opening the discussions of the Automobile Standards Evaluation Subcommittee/Heavy
Vehicle Fuel Efficiency Standards Evaluation Group to the public
・ Overview of the present program regarding fuel efficiency standards
・ Current status of heavy vehicles
2nd Joint Meeting (November 12, 2004)
・ Range of target products
・ Energy consumption efficiency and its measurement methods
3rd Joint Meeting (February 4, 2005)
・ Energy consumption efficiency and its measurement methods
・ Classifications for target standard value settings
4th Joint Meeting (June 27, 2005)
・ Renaming the Joint Meeting・ Hearing from the automobile production and import trade organizations
5th Joint Meeting (September 6, 2005)
・ Target fiscal year
・ Approach to freight vehicles of GVW over 2.5t to 3.5t or less and passenger vehicles (riding capacityof 11 persons or more) of GVW 3.5 tons or less・ Fuel efficiency standard values
・ Display items
6th Joint Meeting (September 22, 2005)
・ Fuel efficiency standard values
・ Interim report
Reception of public comments on the interim report (September 30, 2005)
7th Joint Meeting (November 10, 2005)
・ Final report50

Attachment 8

Heavy Vehicle Fuel Efficiency Standard Evaluation Group,
Heavy Vehicle Standards Evaluation Subcommittee,
Energy Efficiency Standards Subcommittee of the Advisory Committee for Natural Resources and Energy
List of Committee Members

Committee Chairman
Makoto Ikegami

Professor, Dept. of Engineering, Fukui University of Technology

Committee Members
Tsunemi Araki

Environmental Affairs Committee Member, Japan Trucking Association

Norimasa Ohtera

Managing Director, The Energy Conservation Center, Japan

Takeyuki Kamimoto

Professor, Future Science and Technology Joint Research Center, Tokai
University

Risuke Kubochi

Vice-Chairman, Japan Auto-Body Industries Association Inc.

(Kazutaka Obata up to the 3rd meeting)Keizo Saito

Collaboration Coordinator, Collaboration Department, National Institute ofAdvanced Industrial Science and Technology (an Independent Administrative
Institution)

Yasuhiro Daisho

Professor, School of Science and Engineering, Waseda University

Yoshiyasu Nao

Vice-Chairman and President, Japan Automobile Manufacturers Association, Inc.

Kazuo Nagai

Managing Director, Nihon Bus Association

Akira Noda

Director, National Traffic Safety and Environment Laboratory (an Independent
Administrative Institution)

Yasuhiro Fukuma

Director, Japan Automobile Research Institute

Masatoshi Matsunami

President, Japan Automobile Federation

Masanobu Wada

Managing Director, Japan Automobile Importers Association

51