February 14, 2017

Features and Characteristics of
New Building Energy Standards of Japan
Masato Miyata
miyata-m92ta@mlit.go.jp
National Institute for Land and Infrastructure Management
Ministry of Land, Infrastructure, Transport, and Tourism
Masato Miyata, NILIM, Japan, February 14, 2017

Outline

1. Brief Overview of Energy Policy in Japan
2. Evaluation Method (Commercial Buildings)

Masato Miyata, NILIM, Japan, February 14, 20172

1. Brief Overview ofEnergy Policy in Japan

Masato Miyata, NILIM, Japan, February 14, 20173

Status of energy consumption
To stabilize the energy demand and supply in Japan, it is essential to takemeasures to reduce energy consumption in the civilian sector.
Million kl in crude
oil equivalent（Unit: trillion yen, price in 2005）

Real GDP
1973-->2013
increased by 2.5 times

Final energy consumption

1.3-fold
Transport sector
Commercial sector
Residential sector

22.5%(82 million kl)

20.6%

1.8-fold(76 million kl)

14.0%(51 million kl)

Industrial sector

2.9-fold
2.0-fold

43.0%(158 million kl)

0.8-fold[Sources] Comprehensive Energy Statistics, Annual Report on National Accounts, EDMC Handbook of Japan's & World Energy & Economic Statistics[Sources] http://www.enecho.meti.go.jp/category/saving_and_new/saving/zeb_report/pdf/report_160212_en.pdf
Masato Miyata, NILIM, Japan, February 14, 20174

Our Goal (Civilian Sector)
Industrial

Residential

Commercial

Transport

Othermillion t-CO2

1400
1200

101

1000

225

800
600

279

40%
Reduction

201

400
200

73
163
168
122

429

401

2013

2030

0
[Sources] Ministry of Economy, Trade and Industry: Long-term energy supply and demand outlook
July, 2015
5
Masato Miyata, NILIM, Japan, February 14, 2017

Targets
High

BEI
0.00
0.25

ZEB

BEI = Designed primary consumption/ Reference primary consumption (2013)

Nearly ZEB• Realize ZEBs in newly constructedpublic buildings by 2020
• Realize ZEBs in average newly
constructed public and privatebuildings by 2030
[source] Japan’s Strategic Energy Plan (April 2014)

0.50

ZEB ReadyMin.

The Act on the Improvement of Energy Consumption Performance of Buildings

0.80
1.00

Certification Standards(new built buildings, retrofit buildings)

Energy Efficiency Standard(mandatory from 2017)
Masato Miyata, NILIM, Japan, February 14, 20176

History and Future of the Building Energy Standard
1979
1980

1992
1993
1999
2009

The Energy Conservation Law was established.
The Building Energy Standard was established according to thelaw. No obligation was taken on building owners. So the Standard
was similar to recommendation.
The Standard for housings was revised owing to the Gulf War.
The Standard for buildings was revised as well as for housings.
The levels of the Standard were enhanced because of the Kyoto
Protocol.
Reporting on the Standards was mandatory except smallbuildings and housings.

2013

The whole Standard was revised. Primary energy consumption isneeded as criterion index, in addition to envelope performance.

2020

Compliance to the Standard will be mandatory for all new buildings
and residences.
Masato Miyata, NILIM, Japan, February 14, 20177

New Building Energy Conservation Act
Energy Efficiency Act

Large scalebuildings（2,000㎡ or
more）

Mid sizebuildings（300㎡ or more
and less than
2,000㎡）

Small scalebuildings（less than 300㎡）

Non-residential

Residential

Non-residential

Residential

Residential
Construction Client（Housing Top-Runner）

Obligation to notify【Instruction or order, if significantly
inadequate】

Obligation to notify【Instruction or order, if significantly
inadequate】

Obligation to notify

Building Energy Efficiency Act
Obligation to apply【In conjunction with building
confirmation procedure】

Obligation to notify【Instruction or order when deemed necessary
without compliance with standards】

Obligation to notify【Recommend, if significantly
inadequate】【Instruction or order when deemed necessary
without compliance with standards】

Obligation to effort

Obligation to effort

Obligation to effort

Obligation to effort【Recommend or order, if necessary】【Recommend or order if necessary】[source] http://www.mlit.go.jp/common/001178846.pdf (Japanese)
Masato Miyata, NILIM, Japan, February 14, 20178

Scheme for Evaluation of Energy Conservation Compliance andBuilding Certification/Inspection From April 2017
＜Building official ordesignatedconfirmation/inspection
body＞

Building
Confirmation＜Construction client＞

Building
confirmation
application

Submission of plan
to ensure energyefficiency
performance

Conformity
Review Report＜Administrative agency withjurisdiction or registered energysaving review body＞

Review ofconformity toenergy-efficiency
standards

Confirmation certificate
Start construction
Procedures to modify plan (if necessary)

Final inspection

Complete construction/Apply for final
inspection

Inspection certificate
Use
Masato Miyata, NILIM, Japan, February 14, 2017[source]
http://www.mlit.go.jp/common/
001178846.pdf(Japanese)

9Labeling System
Section 7 Emphasize Energy
Conservation Performance ator above Level of Standards• Third party verification(BELS) label with stars.

Less

★★★★★

BEI<=0.60★★★★

BEI<=0.70★★★

BEI<=0.80★★

BEI<=1.00★

BEI<=1.10

More[source] http://www.hyoukakyoukai.or.jp/bels/bels.html
Masato Miyata, NILIM, Japan, February 14, 201710

Labeling System[source] https://www2.hyoukakyoukai.or.jp/bels/info/jireishokai.php
Masato Miyata, NILIM, Japan, February 14, 201711

2. Evaluation Method(Commercial buildings)

Masato Miyata, NILIM, Japan, February 14, 201712Old Energy Standard for Commercial Buildings (〜2013)• The standard used two indicators for assessing the energy
performance of a building.
• Reporting on the standards is mandatory except smallbuildings and housings.
1. For the performance of the building envelope– Perimeter Annual thermal Load (PAL)
2. For the performance of the building equipment– Coefficient of Energy Consumption (CEC)• CEC/AC : CEC for Air-conditioning• CEC/V : CEC for Ventilation• CEC/L : CEC for Lighting• CEC/HW : CEC for Hot water supply• CEC/EV : CEC for Elevators
Masato Miyata, NILIM, Japan, February 14, 2017

Perimeter Zone
13

Revised Energy Efficiency Standard
for Commercial Buildings (2013- )New Standard

Old Standard• There are 5 criterionindices for eachequipment and it is not
an index for wholebuilding performance.

v New index: PAL* andPrimary energy
consumption of 5 equipment(AC, V, L, HW and EV).

• Calculation method havenot been updated forabout 30 years and somenewly technique cannot
be evaluated.

v New calculation method isdeveloped, which canestimate the energy
consumption moreaccurately.

• The values for the PAL
and CEC depend on thebuilding typev Criterion value is definedaccording to types of room.

Masato Miyata, NILIM, Japan, February 14, 201714

Index : Primary Energy Consumption

Primary energy
consumption amount= air-conditioning system+ ventilation system+ lighting system+ hot water supply+ elevator primary+ other (Plug load)- PV andcogeneration system[source] http://www.mlit.go.jp/common/001134876.pdf
Masato Miyata, NILIM, Japan, February 14, 201715

Calculation methodologies• NILIM and BRI have developed new methodologies forevaluating the primary energy consumption.
• The methodologies are expected to be suitable for the
mandatory standard.
– Easy to understand evaluation logic (simplified and streamlined)– Easy to understand evaluation results– A fair, reliable, and transparent evaluation logic– Streamlined and efficient evaluation and review• Provision of evaluation-assistance simulation tools– Defined and unified evaluation rules• Same results regardless of who makes data entries• Same results regardless of who performs a review
Masato Miyata, NILIM, Japan, February 14, 201716

Flow of Calculation of Primary Energy Consumption
for Commercial Buildings

Masato Miyata, NILIM, Japan, February 14, 201717

Reference Energy Consumption
Designer inputs
Designed Specification(geometry, equipment spec)

Climate Zone
( 8 zones )PresetClimate Data

PresetReference Specification
Defined by the standard 2013•

Calculation
MethodBy NILIM and BRI

Compare these consumptions
under same conditions.

Operation
Schedule

Room Type(201 types)

Designprimaryenergyconsumption

Calculation
MethodBy NILIM and BRI

Reference
primaryenergyconsumption

BEI（Building Energy Index）= Design consumption / Reference consumption
Masato Miyata, NILIM, Japan, February 14, 201718

Example of the room types
No.

Type of room
(Office)

No.

Type of room
(Hotel)O-1

Office room

H-1

Guest room

O-2

Office higher heat

H-2

Guest room’s bath room

O-3

Meeting room

H-3

Banquet higher heat

O-4

Tearoom

H-4

Banquet hall with medium heat emission

O-5

Central control

H-5

Banquet hall with low heat emission

O-6

Locker room

H-6

Restaurant

O-7

Canteen

H-7

Lounge

O-8

Hall

H-8

Lounge open only at night

O-9

Lobby

H-9

Shop

O-10 Toilet

H-10

Office room (24 hours)

O-11 Smoking room

H-11

Office room (closed during night)

H-12

Canteen for employees

H-13

Locker room

Masato Miyata, NILIM, Japan, February 14, 201719

Measurement of the Internal Heat Gainin Actual Office Buildings
20

20
Aビル
Bビル(7F)
Cビル(4F)
Cビル(5F)
Dビル(3F)

照明消費電力密度[W/㎡]

16
14

Aビル
Bビル(7F)
Cビル(4F)
Cビル(5F)
Dビル(3F)18

コンセント消費電力密度[W/㎡]

18

平日

12
10
8
6
4
2

16
14

平日

12
10
8
6
4
2

0
00

03

06

09

12

15

18

21

00

Internal heat gain (lighting)

0
00

03

06

09

12

15

18

21

00

Internal heat gain (OA equipment)

0.14
Aビル
Bビル(7F)
Bビル(8F)
Cビル(4F)
Cビル(5F)
Dビル(3F)在室人員密度[人/㎡]

0.12
0.10
0.08
0.06
0.04
0.02
0.00
00

03

06

09

12

15

18

21

00

occupancy
Masato Miyata, NILIM, Japan, February 14, 201720

Example of Assumptions for the Room Usage
Building Type

OfficeType of room

Operation

Internal heat

Time for AC

gain (lighting)[h/year][W/㎡]

Internal heat Internal heatgain

gain (OA(metabolism)

equipment)[person/㎡][W/㎡]

Fresh airIlluminanceintakelevel[m3 /m2 h][lx]

OfficeRoom

3374

12

0.1

12

5.0

750

MeetingRoom

2410

10

0.25

2

12.0

500

30

0.5

0

15.0

ComputerRoom
TeaRoom
Canteen

3374
2410
723

CentralMonitoringRoom

8760

Corridor

3133

LockerRoom
Lobby
ToiletSmokingRoom
KitchenIndoorParking

MechanicalRoom
ElectricalRoom
Kitchenette

StorageRoom
CopyRoom

GarbageStorage

3374
3133
3133
3133

0
0
0
0
0
0
0
0

12
10

0.1

0.25

30

2

20

0.15

30

15

0.03

0

15

0.03

15
15
15

0
0
0
0
0
0
0
0

0.3

0.03
0.03

0
0
0
0
0
0
0
0

0
0
0
0
0
0
0
0
0
0
0
0

5.0

12.0
4.0
4.0
2.5
2.5
2.5
2.5
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0

The information in this table is based on the results of a review in the MLIT
Building Code Development Promotion Project (22 survey items).
Masato Miyata, NILIM, Japan, February 14, 2017

…

750
300
500
500
300
200
500
300
300
750
150
200
200
300
300
500
150

21

Standardized room-use conditions(Office room in office building)
Reference value for heatgeneration density
Lighting: Old Standards
25 W /m2 → 12 W/m2
Human body: Old Standards
0.2 persons/m2 → 0.1
persons/m2
Equipment: Old Standards
10 W/m2 → 12 W/m2

共通

空調

カレンダパターン 年間空調

照明発熱
参照値

在室者数
参照値

[h /年][W /㎡]

3374

1 2 .0

時間

A
室使用パターン別
年間日数

空調時刻（時間）

空調以外の換気
新鮮外気
導入量

年間換気
時間

基準設定
換気風量

基準設定
換気回数

[人/㎡]

[W /㎡][m 3 /㎡・h ][h /年][m 3 /m 2 h ][回][h /年][W /㎡][lx]

0 .1

1 2 .0

5 .0

0

0 .0

-

3133

1 6 .3750

0 .6 9

人体発熱
参照値

待機電力
参照値

作業強度
指数

基準設定
器具形式

基準設定
光源

C

FH F3 2

241

1

7

21

(1 4 )

2

51

2

-

-

(0 )

[W /㎡][W /㎡]

3

73

3

-

-

(0 )

1 1 .93 .0

照明発熱比率スケジュール

Weekdays

Sundays/Holidays

全圧損失[P a]

(0 )

0

1

8

21

(1 3 )

[-]

2

-

-

(0 )

基準設定
換気方式

2

-

-

(0 )

3

3

-

-

(0 )

-

3

-

-

(0 )

人体発熱比率スケジュール

50

50

0
6

9

12

15

Lighting

18

21 24

[日]

3

6

9

12

15

18

21 24

Human body

0

3

6

9

12

15

18

21 24

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

Equipment
19

20

21

22

23

0

0

0

0

0

0

0

100

100

100

100

100

100

100

100

100

100

100

100

100

100

0

0

0

照明発熱比率

0

0

0

0

0

0

0

0

100

100

100

100

50

100

100

100

100

100

100

100

80

0

0

0

平日

人体発熱比率

0

0

0

0

0

0

0

0

100

100

100

100

60

100

100

100

100

100

50

30

20

0

0

0

機器発熱比率

25

25

25

25

25

25

25

25

100

100

100

100

80

100

100

100

100

100

100

50

50

25

25

25

人体発熱比率スケジュール

機器発熱比率スケジュール

100

100

100

50

50

50

0
3

6

9

12

15

18

21 24

3 .8

曜日等
条件

0

0

基準設定
湯使用量

0
0

0

241

L /人日

ン
室同時使用率
１

室
使
用
パ
タ

年間給湯
日数

機器発熱比率スケジュール

50

3

基準設定
保守率

照明点灯時刻（時間）

-

100

0

基準設定
照度

-

100

0

基準照明
消費電力

1

100

照明発熱比率スケジュール

Saturdays

基準設定

換気時刻（時間）

年間照明
点灯時間

給湯

機器発熱
参照値

1

室
使
用
パ
タ

照明

曜日等
条件

0
0

0

0

0

0

0

0

0

24

0

0
17

0

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

ン
室同時使用率
２

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

照明発熱比率

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

人体発熱比率

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

機器発熱比率

25

25

25

25

25

25

25

25

25

25

25

25

25

25

25

25

0

0

18

0
19

0
20

0
21

0
22

Standby power
0
0
0
0
0
0
considered

24
23

土曜日

0

0

0

0

0

0

0

0

0

0

0

0

0

0

25

25

25

25

25

25

25

25

Masato Miyata, NILIM, Japan, February 14, 2017

0
0

22

Measurement of Actual performance of Equipment• In order to estimate the primary energy consumption
accurately, NILIM and BRI measured the actual
performance of the building equipment in several
buildings and developed a method to estimate the actual
performance based on manufacturer catalog data.
Chiller in
Office 1H
事務所1H
1H_R-11.4

1.4

Line: manufacturer catalog data

1.2

Ratio
of Energy
最大入力比（冷房）

Ratioof Capacity
最大能力比（冷房）

Chiller in
Office 1H
事務所1H
1H_R-11
0.8

Plot: Actual measured data

0.6
0.4

×0.95

(n=532)
0

5

10

15
20
25
冷却水入口温度

30

35

40

1.2

×1.07

1
0.8
0.6
0.4

(n=544)
0

5

10

15
20
25
冷却水入口温度30

Inlet chilled water temperature

Inlet chilled water temperature

Cooling Capacity

Energy Consumption
Masato Miyata, NILIM, Japan, February 14, 2017

35

40

23

Calculation flow (air-conditioning system)
Climate zone

Room type, Floor area

Database ofclimate data

Database ofstandard schedules

Temperature, humidity
solar radiation
Input: building envelope- Floor area of rooms,
outdoor wall area,
window area, direction ofwalls and windows,
shading factor, etc.

Input: equipment- Air-handling units’ capacity,
supply air volume, energy
consumption, control system(CAV or VAV), economizer- Secondary pumps’ rated flow
rate, energy consumption,
control system (CWV or VWV)
- Heat source equipment’s
capacity, energy consumption

Coefficients for load calculation

Load
conditions

Coefficients
Performance curves ofheat source equipment

Calculationof dailyheat gain

Estimationof dailyheat load

Performance
curvesa) Heat load calculation
Daily roomheat load

Energy of
air-handling units

Calculationof energy of
air-handlingunits

Appearance
frequencyof heat load

Heat loadof pumps

Calculation ofenergy ofsecondary pumps

Heat loadof heat source

Calculationof energy ofheat source
equipment

Energy ofsecondary pumps
Energy ofheat source equipmentb) Energy calculation
Masato Miyata, NILIM, Japan, February 14, 201724

Concept of Room Heat Load Calculation (1)• Daily heat loads of each room QrL,j are calculated using steadystate heat gain QrG,j .
!!",! ! = ! !! !!!",! ! + !!

• Two kinds of heat gain QrG,j are taken into account:– Heat gain through exterior walls and windows as a result of thetemperature difference= Overall heat transfer coefficient of walls and windows
x area x indoor-outdoor temperature difference– Heat gain through windows as a result of solar radiation= Solar heat gain coefficient x area x shading coefficient
x solar radiation

Masato Miyata, NILIM, Japan, February 14, 201725

Concept of Room Heat Load Calculation (2)•••Coefficients aj and bj are coefficients for converting static heat gain to
dynamic heat load.
These coefficients are determined by using the dynamic thermal load
calculation program NewHASP.
These coefficients are dependent on the zone, room use, and season
and on the use of air-conditioning the previous day.

Masato Miyata, NILIM, Japan, February 14, 201726

Concept of Energy Consumption Calculation• Primary energy consumption of the air-conditioning system.
!",$% = !",$%,$'( (*+,,- ) + !",$%,0(10 (*+,,- ) + !",$%,234 (*+,,- )•The concept used to calculate these values are the same.
– The appearance time of each part load ratio (PLR) band is calculated– The energy consumption of the equipment on each PLR band is calculated
by multiplying the appearance of the load and the energy input, which differs
depending on the control system introduced.

2500"
2000"
1500"
1000"
500"

5"
4"

25"

In"case"of"variable"air"volume""
In"case"of"constant"air"volume"(Energy(Consymop:on([GJ]

Appearance"[h]"Energy(Input(([kW]

Appearance(Frequency([h]

3000"

3"
2"
1"
0"

0"
PLR"
PLR"
PLR"
PLR"
PLR"
PLR"
0"*"0.2" 0.2"*"0.4" 0.4"*"0.6" 0.6"*"0.8" 0.8"*"1.0" 1.0"*"

Appearance frequency of load(from load calculation results)

PLR"
PLR"
PLR"
PLR"
PLR"
0"*"0.2" 0.2"*"0.4" 0.4"*"0.6" 0.6"*"0.8" 0.8"*"1.0"

PLR"
1.0"*"

Energy input(from the equipment characteristics database)Masato Miyata, NILIM, Japan, February 14, 2017

Energy"ConsumpHon"

20"
15"
10"
5"
0"
PLR"
PLR"
PLR"
PLR"
PLR"
0"*"0.2" 0.2"*"0.4" 0.4"*"0.6" 0.6"*"0.8" 0.8"*"1.0"

PLR"
1.0"*"

Primary energy consumption(Load appearance hours
x power consumption)27

Information Disclosed by NILIM and BRI• Official Guides• BRI’s website provides technical information on the
Energy Efficiency Standards:
http://www.kenken.go.jp/becc/index.html– Links to various support tools– Instructions for the tools• How to use
https://www.youtube.com/watch?v=lL1cqCkbFaE
Masato Miyata, NILIM, Japan, February 14, 201728

Web-based Simulation Tool for Compliancewith 2013 Energy Efficiency Standard
Design documents

Computational engine
on cloud computing platforms
XML files

Specification Input Sheet

Calc. results

BRI Website
Download- Excel Sheet- Manual- Interface of
the web-based
simulation toolCalculation
Results

UploadInput the productspecification of thebuilding
equipment
to the Excel file.

Flow for evaluation of a building’s primary energy
consumption in commercial buildings
Masato Miyata, NILIM, Japan, February 14, 201729

Simplified Approach••

An alternative simple evaluation method: the Model Building Method.
Shapes and room uses are considered for each model building use.
– Primary energy consumption is calculated and evaluated by applying
typical specifications for the building envelope and the equipment requiring
calculation to the model building.
Conventional calculation method
The area of each room and thespecifications for the envelope andthe equipment are entered.
Building to be evaluatedModel Building Method
Enter only the main
specifications forthe envelope andthe equipment to
be used in themodel building.

Model building

Web-based programfor primary energy
consumption
calculation

Design value by theconventional method
Baseline value by theconventional method

BPIm
BEIm
Design value by Model Bldg Method
Baseline value by Model Bldg Method

Masato Miyata, NILIM, Japan, February 14, 201730

Model Building Method Input-assist Tool

Masato Miyata, NILIM, Japan, February 14, 201731

Air-conditioning
OA equipment
Elevators

Ventilation
Lighting + OA
Unknown

Lighting
Hot water supply

6,000

5,000
4,000
3,000
2,000
1,000

OfficeRestaurant

Hotel

Hospital

Masato Miyata, NILIM, Japan, February 14, 2017

Calculated

ActualCalculated

ActualCalculated

ActualCalculated

ActualCalculated

0

ActualAnnual Primary Energy Consumption [MJ/m2]

Application to actual buildings

School32

Information Disclosed by Building Research Institute• Building Research Institute’s website provides technicalinformation on the Energy Efficiency Standards:
http://www.kenken.go.jp/becc/index.html– Announcement of an update of the program– Links to various programs– Input sheet (Excel sheet) and sample sheet– Instructions for the program (Building ResearchInstitute document)• Rule book on how to create an input sheet– Details of baseline room-use conditions– Drawings of the model building, etc.
– Information on intermediate and output files from theprogram
Masato Miyata, NILIM, Japan, February 14, 201733

Summary• The building energy standard was revised in April 2013.
– Primary energy consumption is needed as criterion index,
in addition to envelope performance.
• Until 2020, compliance to the standard will be mandatory for
all newly built buildings and housings.
– From April 2017, compliance with the standard will bemandatory for large scale non-residential buildings.
• NILIM and BRI have developed the on-line calculation tools
for the new energy standard and certification system.

Masato Miyata, NILIM, Japan, February 14, 201734