Policy Issue Paper 14-09
A Study on School Building Retrofitting Scheme for Energy Efficiency
G. H. Park
Ⅰ. Research Purpose / 1
Ⅱ. Research Results / 5
Ⅲ. Policy Implications /17
<References> / 19 Contents
Ⅰ. Research Purpose
1. Necessity of Research
□ With the continuous growth of energy demand, many countries around the world face energy shortage and climate change
○ Due to the matter of public acceptance of nuclear power, difficulty of expanding renewable energy supply, countries face difficulties in energy supply security
- In particular, buildings account for about 21% of total energy consumption in South Korea. Since energy consumption in building sectors is expected to grow in the future, the government should come up with countermeasures
○ In order to reduce energy consumption of school buildings, the government has to strengthen design standards of new buildings as well as implement various energy efficiency policies and programs for the existing buildings
- More than half of 11,000 primary and secondary schools nationwide have deteriorated buildings more than 30-40 years old.
- The government introduced a scheme to require energy efficiency certification on buildings, but it is effective only when citizens participate voluntarily. Therefore, more substantial policies to increase energy efficiency
□ Since heating and cooling systems using electricity have been adapted in primary and secondary schools in accordance with school facility renovation policies in Korea, there has been a noticeable increase in electricity consumption in schools
○ The average annual growth rate of electricity tariffs for schools has reached 8% from 2007 to 2012
- As education courses diversifies, energy consumption is increasing. This leads to rise in energy cost
- The government is now implementing Green School Scheme, but only less than 0.5% of all the schools in the country benefit from the policy
○ Therefore, school retrofitting is necessary for reducing energy consumption and improving energy efficiency
- Since schools provide free meals, cooking and water-heating have increased with the expansion of food service facilities
- It is possible to improve energy efficiency by introducing renewable energy system in accordance with changes in energy consumption and its pattern
○ However, many obstacles to implement school retrofitting has to be overcame
- It is indispensible to support initial construction cost for introducing renewable energy system such as photovoltaic power generation and improving energy efficiency
- Through installation of renewable energy facilities in schools, it is possible to improve the students' awareness to renewable energy
2. Research Purpose
○ This study aims to present strategies to improve energy efficiency of school buildings
- More than half of 11,000 primary and secondary schools nationwide have deteriorated buildings more than 30~40 years old. In this context, this research explores the status of energy consumption of primary and secondary school buildings, and suggests the policy implication to improve energy efficiency of school buildings.
- This paper analyzes the energy reduction effect of energy saving technologies by using estimation models
○ This research analyzes economic feasibility of school retrofitting projects by applying B/C analysis, and provides strategies to improve energy efficiency
- For the case of elementary and middle schools, the percentage of public schools is fairly high. Considering this fact, Korean government is feasibly able to implement energy-saving retrofitting of public primary and secondary school buildings.
□ Reference: Energy consumption by building type
<Table 1-1> Energy consumption by building type
(Unit: End use/ thousand toe) Year Mercan
-tile Public Apartment Hotel Health
Care School Department
Store Other All buildings
2000 142 50 597 163 125 130 119 127 1,453
2010 295 107 462 236 254 296 293 238 2,181
2011 294 111 432 241 259 293 291 234 2,155
2012 321 111 429 242 269 304 309 250 2,235
Note: Steam and hot water use are excluded from energy consumption of buildings source: KEMCO(2004), Handbook of Energy Statistics
Ⅱ. Research Results
□ Current Situation of School buildings in South Korea
○ School buildings take account for 13.6%(as of 2012) of total building energy use
- As of 2013, more than half of all the 11,000 primary and secondary schools nationwide have deteriorated buildings more than 30-40 years old.
○ Total energy consumption in schools has increased by 8.7% from 778,628TOE in 2012 to 847,002TOE in 2013
Division 2012 2013
Number of souces 7,589 7,638
Total Energy Use(TOE) 778,628.5 847,002.0
Total Energy Use(kWh) 3,385,502,423 3,682,781,634
Total floor area(㎡) 69,651,851 70,078,602
Number of students(명) 5,902,586 5,605,036
Average Total Energy Consumption(TOE)
Average 102.6 110.9
Max. 303.2 303.2
Min. 33.3 33.3
Average Total Energy Consumption(kWh)
Average 446,106.5 482,165.7
Max 1,318,140.4 1,318,344.1
Min 144,980.7 144,993
Energy Use per Are(kWh/㎡)
Average 49.9 53.8
Max 271.5 293.7
Min 12.9 13.1
Energy use per student (kWh/person)
Average 788.3 899.9
Max 28,735.7 46,935.0
Min 124.5 149.6
<Table 2-1> Energy use of school buildings in South Korea
Source: Ministry of Education(2013), Basic Statistics of Education
○ The earlier before buildings are constructed, especially before 1979, the more energy they consume
- Since South Korea introduced insulation standards in 1979, school buildings constructed before 1979 do not equipped with insulation system. Also, its facilities are worn out, leading to low energy efficiency
○ In terms of type of school ownership, private schools tend to consume a lot of electricity, showing the largest per-area energy use of 62.8kWh - This is because private schools own independent budget, which allows
generous energy use
○ High schools took the top position in energy consumption among schools.
- This is because high schools are characterized long class hour and extra-study hour, which cause large energy consumption
□ Current Situation of Energy Policy in South Korea
○ Green School
- Korean government has undertaken this project to create environmentally friendly schools by renovating deteriorated school buildings since 2009, and put 800billion KRW.
- Investment area includes energy, materials and environmentally friendly facilities, ecology, and interior
Area Average cost per
School(KRW) The rate of investment(%)
Energy 1,326,173,344 27.32
Material and environmentally
friendly facilities 1,079,565,019 22.24
Ecology 660,059,326 13.60
Interior 144,384,376 2.97
Others1) 1,643,406,305 33.86
<Table 2-2> Average cost and the portion of investment of Green School Project during 2009~2010
Source: Korea Institute for Education and Environment, Ministry of Education
○ Zero Energy School Project in Seoul and Improvement of Educational Environment
- Since 2008, Seoul city government has implemented Building Retrofit Project(BRP)
- It aims to estimate energy consumption and the way of energy use through energy diagnosis, and to increase energy efficiency by introducing insulation system or renewable energy facilities
- The city government plans to conduct pilot project, so-call Zero Energy Eco-school in 2014 in order to create an energy-saving awareness and foster a energy self-sufficiency
1) It includes installation of elevator, construction of passageway, seismic capacity evaluation, eco-friend certificate, R&D for green school scheme, and waste management
Unit project Project details Toilet retrofit Patching, Total repair
Electricity facility improvement
Lightings, Receiving and distributing equipments(including transformer)
Cooling and heating system
improvement GHP, EHP, individual heating system Window
replacement External windows, Interior windows, doors External wall
maintenance Face brick, insulation
Fire protection system
improvement Fire extinguish equipment, Automatic Fire Detection System Water-proof
construction Rooftop, porch, basement
Floor
maintenance wood-flooring, terrazzo tiling
Painting External painting
External environment
improvement drainageway, pavement
Others Other construction
<Table 2-3> Unit project and project details
Source: 2014 plan for improvement of education environment
□ School Retrofit Policies in Overseas
○ Countries around the world are implementing various policies to improve energy efficiency in the area of school buildings
- The U.S, Europe, and Japan have been implementing energy retrofitting programs such as EnergySmart School in U.S., ECBCS(Energy Conservation in Building and Community Systems Programme) Annex 36 in Europe, and the Eco-School program in Japan in order to improve their educational environment.
- Each country set a guideline including the specific instructions of
step-by-step retrofitting processes as well as direct fiscal support
□ Implications
○ Specifically, the U.S. and Europe have set the systematic guidelines about the school retrofitting.
- South Korea also implemented school retrofit scheme in order to renovate school building and improve education environment
- However, there’s little information on the effectiveness of the Green-School project because the result of the project is not properly evaluated
□ Analysis on the effects of energy reduction of school buildings
○ After selecting schools of which energy consumption is close to the national average, we investigate the current status of their energy consumption, and conduct simulation analysis by using EnergyPlus program
- We selected a school whose energy use is close to the national average as a benchmark for school retrofitting
- Annual total energy use of the subject of analysis is 72.2kWh/㎡, and gas energy and electricity consumption for cooking accounts for the highest portion in the annual total energy use
- As a result of simulation analysis, total energy consumption is 668,140.1kWh/yr, and hot water supply takes the biggest share (23.3%) of total energy consumption.
○ Among all the energy reduction technologies, when cooling and heating temperature setting system, high-efficiency facilities, and heat recovery system are applied, school buildings can reduce energy use most effectively
- In order to reduce hot water supply, which accounts for the largest part of total energy use, it is necessary to take the introduction of solar power how-water supply system and photovoltaic system into consideration
- If all the element technologies mentioned above are combined at the most to be applied, it is possible to reduce energy use by about 45.1%
[Figure 2-4] Analysis of energy use reduction by applicable technology
Total energyuse(kWh) Energyreductionrate(%)
Benchmark +wall materials +Roof 400mm +triple window +LED light +heatrecovery +solar power +photovolaic 400mm
light freeze protection
heat (electricity) heat(gas)
cooling (electricity) cooling(gas
power generation cooking
Said power Total energy reduction
Ventilation Cooling and heating energy recuction
□ Measures to retrofit school buildings
○ Technology selection to retrofit school buildings
- We present the result of the economic analysis of the applicable construction type in school and the technical elements in energy sectors after calculating the payback period using the input costs and LCC techniques based on energy consumption costs of existing schools.
○ Analysis on energy cost of school buildings
- We analyzed the energy cost of school buildings by calculating the ratio of energy consumptions to energy cost
- Electricity use accounts for 44.6% in the total energy consumption while it takes 60% in energy tariff. This means actual cost of electricity is higher than that of gas
- In energy tariff, basic rate of gas takes only 0.1%, and usage rate take 36.6%. Therefore, reducing electricity consumption is more economical than reducing gas consumption if there is no measure to reduce peak load
○ Cost analysis of applicable element technologies
- In order to compare the ratio of energy reduction cost to initial investment cost among the technologies, we computed the cost input to each element technology
- We applied construction cost for building retrofitting to analyze economic feasibility
· Electricity load-reduction technologies for each construction element(wall insulation, roof insulation, triple low-E glass, LED light, and heat recovery system)
· When renewable energy technologies(solar power systems and solar energy systems for hot water supply) are installed, the construction cost is estimated 2,386,861KRW/kWp for solar power systems, and 1,268,490KRW/ for solar energy system for hot water supply
○ Economic feasibility analysis
- An approximate ratio of annual energy reduction to initial investment cost is helpful in analyzing total energy efficiency
· We calculated the initial investment cost for school retrofit in order to estimate the cost for each element technology
· In terms of initial investment, solar power systems require the most expensive investment of 238,683thousand KRW while LED lights need the smallest initial investment
- We calculated the payback period using the input costs and LCC techniques based on energy consumption costs of existing schools. The result shows that the investment payback period for solar hot water system is the shortest
- In the case of gas tariff which consists of basic rate and usage rate, the usage rate accounts for the most of gas tariff. Accordingly, reduced gas consumption directly leads to the gas tariff reduction
- Therefore, it is desirable to apply a technology to cut gas consumption
at first
- If load-reducing technologies such as window and external wall retrofit are applied, the payback period is remarkably short. Therefore, the most economic way to reduce energy use is to adopt renewable energy facilities
Construction Construction cost per area (KRW/㎡)
Construction area(㎡)
Estimated construction
cost(KRW) External wall
insulation 60,292 2,640 159,170,880
Ceiling insulation 53,468 1,428 76,352,304
Window insulation 213,343 887 189,235,241
LED lightening 22,486 2,174 48,884,564
Ventilation 26,087 5,846 152,504,602
<Table 2-5> Estimated construction cost of load-reduction element technologies for school building retrofit
System Capacity Construction cost
per capacity Total construction cost
Solar power system 100kWp 2,386,831KRW/kWp 238,683,106 Solar system for hot
water supply 100㎡ 1,268,490KRW/㎡ 126,849,035
<Table 2-6> Estimated construction cost of renewable energy facilities for school building retrofit
○ Funding for retrofitting school building
- Funding is needed to improve the energy performance and energy efficiency of the existing deteriorated school building
- To conduct the retrofit projects of buildings of national&public
elementary schools, it is important to relieve the burden of high initial investment cost by providing monetary support
○ Details of School Retrofit Scheme
- Since the early 2014, the government has operated Green Remodeling Creation Center to improve building energy efficiency
- The center provides monetary support with low interest rate if the owner of the building use commercial finances for building retrofit(insulation improvement, installation of energy management system, renewable energy, and highly efficient cooling and heating system), and as a result improve energy efficiency of the building
· Credit line: 20~300million KRW per a school building
· Interest support ceiling: maximum 2million KRW in a year per a building
· Redemption period: redemption by installment in five years(including 20month of grace period)
· The rate of loan support: interest rate of 2%~4% with the degree of improvement of energy performance
○ Scheme for Green Remodeling Creation Center
- School(building owner) makes a contract with licensee for building retrofit. The licensee applies for a loan to commercial banks, and pay back his/her loan according to the commitment
[Fig 2-7] Business model of Green Remodeling Creation Center
Source: Green Remodeling Creation Center(2014), Green remodeling loan support project
- Licensees pay back the initial investment or project cost through the reduced expenditure created from annual energy reduction
- Also, licensees take charge of retrofit planning, design, construction, and energy consulting, conducting a comprehensive remodeling projects - Green Remodeling Creation Center(government) basically utilizes
commercial finances, but gives the initial investment with low interest rate as the second resort
- However, the loan interest supports are suspended after the 5 year-redemption period, and building owner has to take a burden of paying interest. This is pointed as a limitation of the Green Remodeling Scheme
- Therefore, it is necessary to extend interest support period to more than
ten years, the period considered to be the least time to redeem the loan
- The core mechanism of the scheme is redeeming the project cost by reduced energy expenditure. Accordingly, the government has to guarantee realistic payback period and appropriate redemption period in order to encourage more schools to participate the scheme(foreign countries generally provide a long-term low interest rate loan over 20~25 years)
<Table 2-8> Role of project entities
Entity Role
Green remodeling
Creation Center
○ Reviewing licensees’ business plan, and providing technical support
○ As a second resort, providing financial support with lower interest rate than commercial bank
licensees
○ Writing business plan after having energy performance diagnosis(utilizing energy evaluation companies)
* Selection Remodeling school and energy performance diagnosis expert
○ Licensees finance retrofit cost on behalf of building owner
○ Taking out an insurance for guaranteeing energy performance Commercial
financial companies
○ Financing a loan for project with low interest rate, and paying back it from reduced energy expenditure
○ Providing a loan for green remodeling and supporting low interest rate financial goods
○ Insurance companies develop insurance products guaranteeing energy performance
Building owners
○ After reviewing business plans, building owners make a contract and finance project cost from commercial bank
* After remodeling, building owner has to energy consumption information in order to prevent reckless energy use
○ Redeeming project cost by installment with reduced energy expenditure
Source: 2013 Report on measure to facilitate green remodeling scheme for reducing energy consumption
Ⅲ. Policy Implications
□ The following have to be considered to reduce energy use of school buildings and to increase energy efficiency
○ In order to facilitate the promotion of Building Energy Retrofit Project, the most important thing to be done is the energy audit and performance assessment of buildings in schools.
- Each of these energy assessments and retrofit projects should be conducted after reflecting the circumstances of each individual school.
- All types of retrofitting including school buildings should carefully reflect what consumers need in the projects. The system for consumers to access easily to all retrofit information should be essentially provided.
○ It is required to present a guideline by utilizing Energy Plus program for school building energy retrofit.
- In order to improve the efficiency of hot water supply system, which takes the biggest part in energy consumption of school building, introduction of renewable energy system has to be considered.
- For schools offering lunch or dinner, especially, solar power hot water supply system should be considered.
- In the case of schools, since the building-to-land ratio and floor-area ratio are low, introduction of the system of photovoltaic should be considered to save not only electricity use in schools but also nationwide electricity use.
○ To conduct the retrofit projects of buildings in national&public elementary and secondary schools, funding is urgently needed.
- If necessary, modification and supplementary revision of related Act or Decree is needed to get funds for school retrofitting.
- One way to obtain necessary funds for school retrofitting projects is to use the funds available in the public sector such as ‘Energy Use Rationalization Fund'.
- Rental fees obtained from renting a roof of the school to solar system company can be transferred to the school budget.
- Korean government recommends that solar system companies should install the monitoring room in school for the publicity and educational purposes of schools.
○ The most effective and efficient technology should be applied to enhance energy efficiency of the existing school buildings.
- The analysis result shows that for solar hot water system, the investment payback period is 7.7, and solar power system is about 13 years.
- In contrast, in the case of investment in window retrofit and insulation, the payback period is remarkably short. Therefore, application of renewable energy system should be firstly considered to reduce energy use.
- Finally, it is vital to enlarge renewable energy system at the national level.
< References >
1.
참고문헌
건설교통부·환경건설교통기술평가원(2004), “건축물의 LCA를 위한 원단위 작 성 및 프로그램 개발 연구”
교육부(2013), 간추린 교육통계 교육부(2013), 교육기본통계
교육과학기술부, 학교보건법 시행규칙(교육과학기술부련 제12호 일부개정), 환 기ㆍ채광ㆍ조명ㆍ온습도의 조절기준(제3조 제1항 제1호 관련)
그린리모델링 창조센터(2014), 그린리모델링 이자 지원사업
그린리모델링 창조센터(2013), 2013 건축물 에너지 수요절감을 위한 그린 리모 델링 활성화 방안
김덕우, 박철수(2009), “외피 친환경 성능평가 Ⅱ : 광선반, Retrolux, 한국태양 에너지학회, 춘계학술발표대회 논문집”, 2009-04. 83-90.
김동균 외(2011). EnergyPlus의 시뮬레이션 결과와 실제 냉방에너지 사용량의 비교 분석 및 GHP와 EHP의 에너지 성능비교에 관한 연구, 대한건축학회 지, 27(5). 237-244
김영구(2007). 초,중등 교육시설의 유지관리비 분석 -인천광역시 초,중등학교를 중심으로-, 한국교원대학교. 석사학위논문.
김인호, 안동만(1999). 환경친화형 학교모형 개발 연구, 교육정책개발 연구과제, 교육부.
김인호(2007). 친환경 학교를 위한 학교숲 운동 개선방안 -행정주도의 학교숲
조성사업을 중심으로, 한국교육시설학회지, 14(1). 121-129.
남영숙(2007). 서울시 지속가능발전과 환경교육 활성화를 위한 환경교육 정책 개선 방안, 환경교육, 20(3). 125-133.
박재성(2008). 단지규모 태양광 및 태양열 시스템의 최적공급 방안 연구, 한밭 대학교, 석사학위논문.
산업자원부(1999). 건물의 에너지원단위기준(안) 연구.
산업자원부(2000). 건물 에너지절약을 위한 제도 개선 연구. 산업자원부(2007). 신․재생에너지 RD&D 전략 2030 [태양광],
산업자원부·신재생에너지센터(2007). 신재생에너지자금·세제지원 안내. 산업통상자원부(2014), 제2차 에너지기본계획
에너지관리공단(2014), 에너지통계 핸드북
조진일 외 12인(2008). 제로에너지 모형개발연구(Ⅰ), 한국교육개발원. 조진일 외 (2009). 제로에너지 모형개발연구(Ⅱ), 한국교육개발원.
최돈형․노경임(2000). 현장체험중심의 환경교육 활성화방안 연구-독일의 환경 교육이 주는 시사점을 중심으로-, 환경교육, 13(2). 51-62.
한국교육개발원(2009), “노후학교시설 개축 판별모델 개발” ASHRAE(1992). Active Solar Heating Systems Design Manual.
DOE(2013a). Advanced Energy Retrofit Guide
DOE(2003b). Rebuild America EnergySmart School program brief DOE(2003c). Financing an EnergySmart School
Deutscher Taschenbuch Verlag(1990). dtv-Atlas zur Ökologie.
DFEE(1999). The Outdoor Classroom. BUILDING BULLETIN 71 2ND EDITION.
Duffie, J. A. and Bechman, W. A.(1991). Solar Engineering of Thermal Process, 2nd Edition", Jonh Wiley & Sons.
Eneco Energie(2004). Renewable energy Projects.
EPIA Report(2008). Solar Generation V-2008.
European Commission(2014). Technical Guidance: Financing the Energy Renovation of Buildings with Cohesion Funding.
Felex A Peuser, Karl-Heinz Remmers, Martin Schnauss(2002). Solar thermal system - Successful Planning and Construction. SOLARPRAXIS, Berlin.
Felicitas Kraus(2005). Building Energy Conservation dena's activities, Kemco-dena Seminar on ESCO and Building Energy.
German Solar Energy Society, Ecofys(2004). Planning and Installing, Solar Hans Herbert Ehm(1995). Waermeschutzverordnung '95, Der Weg zu Niedrigenergiehaeusern, Bauverlag.
IEA/PVPS(2003). Trends in Photovoltaic Application" Survey reports of selected IEA countries between 1992 and 2002, TI-12:2003
J.A. Duffie & W.A. Beckman(1991). Solar Engineering of Thermal Processes(2nd ed), Wiley, New York.
Keep scotland beautiful(2003). Ecoschoos Scotland Handbook.
Koichi Shinpo(2011), 일본 내 환경 친화적 학교 건축 발전 방안
Vishal Garg, Kshitij Chandrasen, Development and performance evaluation
of a methodology, based on distributed computing, for speeding EnergyPlus simulation, Journal of Building Performance Simulation Vol. 4 No. 3 257p~270p
Scheme for Energy Efficiency
Printed on February 23, 2015 Issued on February 23, 2015
Author：Ki-Hyun Park Publisher：Joo-Heon Park
Published by Korea Energy Economics Institute,
(Address) 405-11, Jongga-ro, Jung-gu, Ulsan, 44543, Korea, (Phone) +82-52-714-2114, (Fax) +82-52-714-2028 Registered on December 7, 1992
ⓒKorea Energy Economics Institute, 2015
