This document discusses challenges for Korea in achieving near-zero energy buildings (nZEBs) to address climate change. It provides background on Korea's greenhouse gas emission reduction targets and milestones for nZEB adoption. Core nZEB technologies are highlighted, such as high-efficiency lighting and insulation. Different definitions of nZEBs are examined, including the 2015 definition from the National Institute of Building Sciences that simplified earlier definitions. Key drivers for nZEBs are identified, including building codes and standards, compliance structures, tools, education and training. The status of these drivers in the US, EU and Korea are briefly compared.

1. Challenges of Korea toward
nZEB against Climate Change
Architectural Environment and Energy Research Lab.
Department of Architectural Engineering
Chungbuk National University
Donghyun Seo, Associate Professor, Ph.D
(seodh@cbnu.ac.kr)

2. Introduction
2
온실가스로드맵: http://2030ghg.or.kr 국회입법조사처: www.nars.go.kr
GHG Emission
Reduction Target
Road to nZEB Milestone
Nov. 2009
30% Reduction by 2020
based on BAU
(COP15)
Jun. 2015
37% Reduction by 2030
based on BAU
(COP21)
2015 2020 2025
FRA: Mandatory ZEB
GER: Mandatory ZEB
SWE: Mandatory ZEB
ENG: Mandatory ZEB
USA:Mandatory ZEHome Mandatory ZEB
Mandatory ZE_AllJAP:Mandatory ZEPub
ZE_AllROK:Mandatory ZEHome
Challenge of Building Sector for GHG Emission

3. • Building energy saving strategies are gathering concerns due
to GHG and energy cost fluctuation in worldwide
• Building energy accounts for 35~40% in advanced countries
and around 20% in developing countries, that is each country
has their own landscapes for the strategies setting
• However, most governments and companies are considering
that nZEB will be main tools for reducing building energy
• Especially, governments are driving to create nZEB market
throughout codes, regulations, standards and incentives
• There are already lots of information on the required
technologies toward nZEB. In this presentation, what else
components are required for rapid provision of nZEB in S.
Korea throughout
1) nZEB definitions
2) nZEB driver components
3) identify what is still “in necessary”
Introduction
3

4. Technologies toward nZEB
* Frost & Sullivan (2014), Enabling Technologies for NZEB
4

5. Technologies toward nZEB
* Frost & Sullivan (2014), Enabling Technologies for NZEB
5

6. • Core technologies for nZEB will be:
– High efficient lighting (LED, oLED )
– High performance glass and smart glass
– High performance insulation
– High efficient HVAC
– EMS (Energy Management System)
– RE (esp. Solar PV)
Technologies toward nZEB
(source: Navigant Research, 2015)
6

7. • nZEB Related Trends
– nZEB owners are recognized as early adopters
– Most of nZEB, especially commercial, are pilot buildings to
demonstrate performance and image-making of companies
– The most strong driving force for nZEB is Regulation
• EPBD (EU), Title 24 (CA, USA), IECC, etc
– The next strong driving force for nZEB is willingness of
business and individuals
• AIA Architecture 2030
– Barriers: Arbitrary of definition and what success looks like.
Since various means are applicable, it is difficult to define
nZEB in regulation, codes, standards, and incentives (esp.
EU)
Overview on achievement so far
(source: Navigant Research, 2015)
7

8. • EU EPBD’s nZEB Definition in Article 2
Definition of nZEB
“ ‘nearly zero-energy building’ means a building that has a very
high energy performance, ... The nearly zero or very low amount
of energy required should be covered to a very significant extent
by energy from renewable sources, including energy from
renewable sources produced on-site or nearby ”
8

9. • Four definitions based on energy type (NREL, 2010)*
– Net Zero Site Energy (ZNE:A): A site NZEB produces at
least as much RE as it uses in a year, when accounted for at
the site.
– Net Zero Source Energy (ZNE:B): A source NZEB
produces (or purchases) at least as much RE as it uses in a
year, when accounted for at the source.
– Net Zero Energy Costs (ZNE:C): In a cost NZEB, the
amount of money the utility pays the building owner for the
RE the building exports to the grid is at least equal to the
amount the owner pays the utility for the energy services and
energy used over the year.
– Net Zero Energy Emissions (ZNE:D): A net-zero emissions
building produces (or purchases) enough emissions-free RE
to offset emissions from all energy used in the building
annually.
Definition of nZEB
* Net-Zero Energy Buildings: A Classification System Based on Renewable Energy Supply Options, the National Renewable Energy
Laboratory (NREL)
9

10. • NIBS(2015) settled guides for new nZEB definition. It
should:
– Create a standardized basis for identification of ZEBs
for use by industry.
– Be capable of being measured and verified, and
should be rigorous and transparent.
– Influence the design and operation of buildings to
substantially reduce building operational energy
consumption.
– Be clear and easy to understand by industry and
policy makers.
– Set a long-term goal and be durable for some time
into the future.
Definition of nZEB
* National Institute of Building Sciences (2015), A Common Definition for Zero Energy Buildings, DOE (EERE)
10

11. • Four new definitions are distinguished by boundary and:
– Zero Energy building (ZEB): An energy-efficient building
where, on a source energy basis, the actual annual
delivered energy is less than or equal to the on-site
renewable exported energy.
– Zero Energy Campus: An energy-efficient campus where, on
a source energy basis, the actual annual delivered energy is
less than or equal to the on-site renewable exported energy.
– Zero Energy Portfolio: An energy-efficient portfolio where,
on a source energy basis, the actual annual delivered
energy is less than or equal to the on-site renewable
exported energy.
– Zero Energy Community: An energy-efficient community
where, on a source energy basis, the actual annual
delivered energy is less than or equal to the on-site
renewable exported energy.
Definition of nZEB
* National Institute of Building Sciences (2015), A Common Definition for Zero Energy Buildings, DOE (EERE)
- Portfolio: A collection of building sites that contains renewable energy production systems owned/leased by a single entity.
- Campus: A group of building sites in a specific locality that contain renewable energy production systems owned by a given institution.
- Community: A group of building sites in a specific locality that contain renewable energy production systems.
11

12. • Four New Definition of NIBS (2015)*
Definition of nZEB
* National Institute of Building Sciences (2015), A Common Definition for Zero Energy Buildings, DOE (EERE)
12

13. • Four New Definition of NIBS (2015)*
Definition of nZEB
* National Institute of Building Sciences (2015), A Common Definition for Zero Energy Buildings, DOE (EERE)
• This new definitions looks like not much changed, but it is very
simplified and cleared than previous definition.
• This definition also could cover future energy supply environment
change such as smart grid and RE system integrated buildings
and sites
• Even non-experts are easy to understand the way to reach nZEB
• As a small conclusion, this kind of definition should be settled in
each country so that it could be incorporated building energy
codes and standards to avoid confusion of private sectors
13

14. nZEB Driving System
Code
development
•develop the model
code
Code adoption
•adopt the code at
the state and local
levels
Code
implementation
•design and constr-
uction based on
codes
Compliance
checks
•design,construction
and occupancy
phases check
Compliance
evaluation
•evaluate overall
compliance rate
Education and
Training:
Designer, Engineers
Education and
Training :
Inspectors
Fundamental Data
Tools
Code enforcement:
• Penalties and
Rewards
Code Compliance:
• rate
Fundamental Data
Tools
Tools

15. nZEB Core Drivers
Fundamental Data:
Building Energy DB, Benchmark Data, Climatic Zones, Weather, etc.
Codes &
Standards:
IECC, EPBD,
LEED, etc. Tools:
eQUEST, PKPM-
EC, COMcheck,
etc.
Code
compliance &
enforcement
structure:
• check phases of
each progress
• Penalties and
Rewards
• Compliance rate
Criteria Data
Criteria/
Format
Data
compliance
Stats.
Data
Education
and Training:
Agency, Engineer,
Students
Engineer
Inspector,
Agents
Policy
Maker
15

16. nZEBs Drivers: US and EU
Fundamental Data
Codes &
Standards
Code compliance &
Enforcement
Tools
Energy Disclosure
Benchmark Data
Typical Weather
Files
Design Guides
Residential
Non-Residential
Rating &
Certification
Voluntary Standard
Plan Review
Construction Check
Pre-Occupancy
Check
Penalties
Energy Simulation
Compliance Check
RE Simulation
Education/Training
Incentives/Budget
Yes
N/A
Yes
Yes
Yes
N/A*
Yes*
Yes*
Yes*
Yes*
* : EU has many countries. this is only for Germany16

17. nZEB Drivers: US and EU
Pros Cons
USA • Transparency
• Code compliance software
• Regular and frequent code revision
cycles
• Flexible code in design and
compliance pathways
• Local “stretch” codes
• Utility involvement
• Support from industry, (non-)
governmental organization
• Code revision leads times
• Retrofit project is relatively rare
• Funding and use of third parties
• Lack of compliance rate data
EU • Regular and transparent code
revision cycles
• Various voluntary standards:
Passive House, Minergie
• Learning by sharing: Concerted
Action EPBD (since 2007)
• Compliance with building codes
• Comparing building code stringency
• Low-energy building cooling and
lighting standards
• Gaining more experience with nZEBs
LBNL, Building Energy-Efficiency Best Practice Policies and Policy Packages, 2012
17

18. nZEB Drivers: Korea
18
~30% Low E Bldg.
(~2012)
~70%Low E Bldg.
(~2017)
ZEB Res/Pub Bldg.
(2025)
U-value
2012
Enforcement
2013
Enforcement
2015
Enforcement
2017
Enforcement
EPI
2012 Revision-
Coverage
2015 Revision-
Exterior Shade
2016 Unifying Plan with
Performance based Code
PBC
2011 +10000㎡
Non-Residential
2020 +500㎡
All Bldg.
GBPA 2012 Enact
GHG Reduction 2014 Building Energy Data DB
2017 Energy Disclosure
(GreenTogether)
Green
Remodeling
2014 Green Remodeling Pilot
Project Initiation
~2018
150/28,000 Projects
EPRS
2011 extend to
non-residential
2013 All
Buildings
2017 ZEB
Certification
G-SEED 2011 G-SEED
2015 G-SEED
Extend Cvrg
2020 Unifying
w/ GBPA
Long-term
Plan of
Gvn’t
EPC
2013 Certification
in real estate
2015 Publish
Certification
EPI: Energy Performance Index, PBC: Performance Based Code (소비총량제), GBPA: Green Building Promotion Act
EPRS: Energy Performance Rating System, G-SEED: Green Standard for Energy and Environmental Design
EPC: Energy Performance Certificates

19. nZEBs Drivers: Korea
Fundamental Data
Codes &
Standards
Code compliance &
Enforcement
Tools
Energy Disclosure
Benchmark Data
Typical Weather
Files
Design Guides
Residential
Non-Residential
Rating &
Certification
Plan Review
Construction Check
Pre-Occupancy
Check
Penalties
Energy Simulation
Compliance Check
RE Simulation
Education/Training
Incentives/Budget
Partly
N/A
Yes
Yes
Yes
Voluntary Standard
Green Building
Construction
Assistance Act
Green Building
Construction
Assistance Act
None
None
None
19

20. Identified Gaps
• Lack of building energy DB for disclosure and benchmarking:
▪ Projects are on going in some institutes such as KICT, KEEI, KEMCO but they are not
integrated and don’t share final target
• No building energy code that is based on holistic approach:
▪ Current prescriptive approach based code should add performance based code option
• Compliance check is implemented for design phase only:
▪ Building energy efficiency rating system has design and pre-occupancy phase
inspection procedure
▪ Compliance check cycle should be build as well as monitoring compliance rate
• Limited Penalties:
▪ Holding occupancy permit and no fine is imposed
▪ More strict and strong penalties are required. More innovative incentives are required
• No tools for detailed building energy simulations:
▪ Simple steady-state simulation tools are officially permitted to use. This causes design
of building energy efficiency technologies making too simple problem. Eventually, this
makes not fully energy efficient buildings, slashing related experts’ values and unable to
achieve rapid nZEB provision.
20

21. 21
USAF
Station
(Abbre.)
Longitude
(degree)
Latitude
(degree)
Elev.
(m)
DQ Missing Year
(non-solar)
Measured
Solar (global)
470950 철원 38.15 127.30 154 C 1981~1988 1988~1991
471000 대관령 37.69 128.76 843 C 1981~ 1991 1981~2010
471010 춘천 37.90 127.74 77 C - 1981~2010
471050 강릉 37.75 128.89 26 C - 1981~2010
471080 서울 37.57 126.97 86 C - 1981~2010
471100 서울(A) 37.33 126.65 19 A -
471120 인천 37.48 126.62 69 C - 1981~2010
471140 원주 37.34 127.95 150 B 1981~1988 1981~2010
471150 울릉도 37.48 130.90 221 C - -
471190 수원 37.27 126.99 34 C - 1986~2006
471210 영월 37.18 128.46 240 C 1981~1994 -
471280 청주(A) 36.42 127.30 66 B 91(3) -
471300 울진 36.99 129.41 49 C - -
471310 청주 36.64 127.44 57 C - 1981~2010
471330 대구 36.37 127.37 68 B - 1984~2010
471350 추풍령 36.22 127.99 243 C - 1981~2010
471360 안동 36.57 128.71 139 C 1981~1983 1983~2010
471380 포항 36.03 129.38 2 C - 1981~2010
471400 군사 35.99 126.71 26 C - -
471430 대구(A) 35.53 128.37 61 C 1981~2010
471460 전주 35.82 127.15 53 C - 1981~2010
471520 울산 35.56 129.32 35 C -
471530 부산(A) 35.11 128.56 15 B - -
471550 마산 35.19 128.57 11 C 1981~1988 -
471560 광주 35.17 126.89 71 C - 1981~2010
471590 부산 35.10 129.03 69 C - 1981~2010
471650 목포 34.82 126.38 38 C - 1981~2010
471680 여수 34.74 127.74 66 C - -
471700 완도 34.40 126.70 35 C 1981~1983 1981~1982
471820 제주(A) 33.30 126.33 27 B - -
471840 제주 33.51 126.53 20 C - 1981~2010
471890 서귀포 33.25 126.57 50 C - -
471920 진주 35.21 128.12 21 C - 1981~2010
471220 오산 37.05 127.02 12 A - -
• Raw Data Source: NCDC ISH
• Period: 1981~2010 (30 years)
• Measured Solar: KMA, KIER
• Developed Tool: TMWgen®
서동현 (2017)
Development of Typical Weather: TMWgen
Efforts of AEER (Bldg. research lab of CBNU)

22. 22
Development of Typical Weather: Real_Time TMWgen
1
2
Source Code (Python)
서동현 (in review)
Efforts of AEER

23. 23
Climatic Zone for Building Code with 30 years weather analysis
① Current Zones
[녹색건축물조성지원법] 건축물에너지절약설계기준 별표1
- A+B : Jungbu Zone
- C+D : Nambu Zone
- E : Jeju Zone
② Proposed Zones
- A : 중부지역 (2670~2900℃⋅day)
- B : 경기도 및 강원도 산간지역 (3190~4240℃⋅day)
- C : 중부 및 남부 혼재 지역 (2900~3100℃⋅day)
- D : 남부지역 (2150~2670℃⋅day)
- E : 제주도 (1385~1710℃⋅day)
서동현 (2014)
Efforts of AEER

24. 24
Prototypical APT: Benchmarking Data
• Prototypical Building Model can be used as Benchmark Building for helping others get energy target in
design process
Categories DefinedValue
구조방식 계단형(탑상형)
준공년도 1990-99년
열관류율
1987년열관류율적용
창의일사획득계수:0.82
층고 2.6m
층수 15층
바닥면적 전용면적85m2
장단변비 장방형1:3
주향 정남향
창면적비
전면:57.8%,후면:37.9%,
전체평균:47.3%
침기&환기율 난방공간:0.7ACH,비난방공간:2.0ACH
가구원수 4인
냉난방설정온도
및기간
난방:11월1일～3월31일(20℃)
냉방:6월11일～9월10일(28℃)
기계설비종류
및효율
가스보일러(도시가스),효율:80%
에어컨,COP:2.9
조명밀도
및프로파일
세대평균:3.83W/m2
스케줄:그림3참조
가전기기사용밀도
및프로파일
세대평균:6.4W/m2
스케줄:그림4참조
인체발열량
및재실프로파일
인체발열량:설비공학편람
재실율:그림5참조
급탕량및시간별
급탕프로파일
시간최대급탕량45.5liter/세대
급탕스케줄:그림6참조
Measured End-Use Ratio (Daejoen)
Estimated End-Use Ratio (Daejeon)
서동현 (2014)
Efforts of AEER

25. “Non-residential building energy national survey”(2014~2016)
25
Prototypical Non-Residential Building : Benchmarking Data
• Submit Energy Efficiency Indicator for IEA
• Evaluate National Building Policy Efficiency
• Support Building Industries in Design, Construction, and Management
Building
Simulation
▪ Building
▪ Service Systems
▪ Usage pattern
▪ Energy
Consumption
National Building
Survey
▪ Office
▪ Commercial
▪ Education
▪ Telecommunication
Typical Building
Definition
Efforts of AEER

26. 26
✓ Total 15 prototypical building models are defined throughout recent research
KEEI (2016)
Efforts of AEER
Prototypical Non-Residential Building : Benchmarking Data
Commercial Office Educational

27. 27
Summary
1. Building sector of Korea is experiencing rapid policies change by
governmental enforcement. Since not all participants are well
understanding in terms of technologies and policies, it is required to
persuade and educate them what ZEB looks like.
2. More supportive and efficient structure of ZEB drivers should be
constructed by Korea government.
3. Especially, fundamental structure, compliance check, remodeling policy
are very urgent parts in Korea building sector.

28. www.chungbuk.ac.kr
Thank You!