energy-efficiency standards for residential buildings in China

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Energy and Buildings 36 (2004) 11911196

Progress in energy-efficiency standardsfor residential buildings in China

Siwei Lang

China Academy of Building Research, 30 Bei San Huan Dong Lu, Beijing 100013, China

Received 25 March 2003; accepted 16 September 2003

Abstract

The paper briefly describes energy-efficiency standards that have been issued for residential buildings in Northern and Central China

as well as energy-efficiency inspection standards and specifications for renovation of existing residential heating systems in NorthernChina, and development of energy-efficiency standards for Southern China. The paper also describes barriers to improving the energy

efficiency of residential buildings in China and strategies for overcoming these barriers, including reform of the method of payment for

heating in Northern China. Finally, future prospects for further developing energy-efficiency standards for residential buildings in China

are addressed.

2004 Elsevier B.V. All rights reserved.

Keywords: Energy-efficiency design standards; Residential buildings; Heating payment reform

1. Introduction

In China, the building sector is divided into civil and in-dustrial subsectors; the civil subsector is further divided into

residential and public buildings. Public buildings include

commercial structures such as department stores, supermar-

kets, rental office buildings, apartments, hotels, restaurants,

banks, post offices, airports, rail stations, and buildings used

for education, science, research, medicine, sports, and com-

munications services.

Economic development and a desire for improved liv-

ing standards have spurred rapid construction and develop-

ment in China during the past 20 years. During the early

1980s, new construction floor area totaled 700800 mil-

lion m2 per year. By the early 1990s, the yearly total was

1000 million m2, and the annual total in recent years has

been 16001700 million m2, of which 400500 million m2

are urban residential buildings, 400500 million m2 are pub-

lic and industrial buildings (mainly in cities), and 700800

million m2 are residential buildings outside cities. This rapid

rate of construction has implications for energy consump-

tion; in particular, the energy consumption per meter square

for heating in traditional residential buildings (i.e. those

Tel.: +86-10-8427-5106; fax: +86-10-8427-5106.

E-mail address: [email protected] (S. Lang).

that do not meet the new energy-efficiency standard de-

scribed in this paper) in China is twice that of residential

buildings in developed countries under the same weatherconditions.

China covers a vast geographical area, and the tempera-

ture difference from the north to south is very large, espe-

cially in winter. In general, the average monthly temperature

in China in January is 1018 C lower than that of other

areas of the world at the same latitude; in July, the average

monthly temperature is 1.32.5 degrees higher than those

other areas. According to the national Standard of Climatic

Regionalization for Architecture GB 5017893 [1], China

is divided into the following zones based on climate char-

acteristics: very cold, cold, hot summer and cold winter,

hot summer and warm winter, and moderate (Fig. 1). Air

conditioning and heating requirements for different zones

are as follows: in the very cold zone, the major requirement

is heating, and few residential buildings are equipped with

air conditioning. In the cold zone, the primary requirement

is heating, followed by air conditioning. In the hot summer

and cold winter zone, both air conditioning and heating are

needed. In the hot summer and warm winter zone, the major

requirement is air conditioning, and few residential build-

ings require heating. In some parts of the moderate zone,

heating is needed; in other parts, both heating and air condi-

tioning are needed. The availability of heating and air con-

ditioning depends on several factors, including the degree of

0378-7788/$ see front matter 2004 Elsevier B.V. All rights reserved.

doi:10.1016/j.enbuild.2003.09.014


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1192 S. Lang / Energy and Buildings 36 (2004) 11911196

Fig. 1. China Climate map.

economic development in an area, the availability of energy

supplies, and requirements for environmental protection.

Building energy consumption data cover numerous end

uses, including air conditioning, heating, lighting, appli-

ances, cooking, domestic hot water, and others. However,

heating and air conditioning account for the largest share

of residential energy consumption. Along with Chinas

economic development, energy consumption has increased

rapidly. In 1999 energy consumption in buildings repre-

sented 27.6% of total energy consumption in China [2]. The

energy-efficiency goal for residential buildings in Chinais to reduce the energy consumed for air conditioning

and heating while maintaining comfortable indoor thermal

environments.

Energy-efficiency efforts began in the early 1980s in

China. With supports of the State Economic and State Plan-

ning Commissions, the Ministry of Construction (MOC)

approved projects to investigate the amount of energy con-

sumed by space heating and to develop an energy-efficiency

design standard for residential buildings in the very cold

and cold zones of the country (i.e. in Northern China)

where very large amounts of energy were being consumed

for heating. More than half the countrys total floor area

(all types of buildings) is located in Northern China where

the heating season is between 3 and 6 months long. Statis-

tics show that, by the end of the 1980s, heating energy

consumption was 130 million tons standard coal equiva-

lent or about 11.5% of total energy use in China and more

than 20% of total use in Northern China (and about 50%

of total energy use in some cities in the very cold zone

of the country). Since 2000, MOC has moved to develop

energy-efficiency design standards for residential buildings

in Central and Southern China as well. The MOC expects

that standards for residential buildings in all climate zones

in the country should be issued by the end of 2003.

2. Energy-efficiency design standard for heating in

residential buildings in very cold and cold zones

2.1. Energy conservation design standard for new heating

in residential buildings JGJ 2695

MOC issued the Energy Conservation Design Standard

for New Heating in Residential Buildings, JGJ 2686,

in 1986. The goal of the standard was a 30% decrease in

heating energy consumption relative to the consumption of

typical Chinese residential buildings (base buildings) de-signed in 19801981. In December 1995, MOC issued a re-

vised standard (JGJ 2695) with an increased energy-saving

goal of 50%. The chief author of the standard was the

China Academy of Building Research. JGJ 2695 includes

indices of building heat loss and coal consumption for heat-

ing along with sections on thermally efficient building and

heating design. A table (in Section 4 of the standard) allows

building designers to easily determine the heat-transfer co-

efficients for each part of the building envelope as long as

the buildings shape coefficient (ratio of exterior surface

to floor area) is less than or equal to 0.3, and the ratio of

window to wall area is less than 0.25 for north windows,

0.30 for east and west windows, and 0.35 for south win-

dows. If the shape coefficient and/or the ratio of window

to wall area are not within the values specified above, the

designer can calculate the building heat-loss index and

coal consumption for heating using equations presented in

Section 3 of the standard. This process entails changing

heat-transfer coefficients for each part of the building en-

velope to arrive at values that correspond to those listed

in Appendix A of the standard. The standard provides (in

Section 5), information that permits designers to match to-

tal installation capacity of a heat source with the building

heating load and also includes information on hydraulic


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also addresses retrofits of the building envelope and heating

systems of existing structures without central heating that

are located in these zones.

2.4. Reform of heating payment system to promote

development of energy efficiency in buildings in China

In order to promote energy efficiency in buildings in very

cold and cold zones of China, the Chinese government plans

to alter the method of payment for heating. The reform

will transform the current social welfare system into a mar-

ket system and will also continue to promote central heat-

ing as the preferred strategy; to develop clean, economical,

high-efficiency heating systems; and to support the intro-

duction of competition in the market heating supply. The

heating payments currently made by government and other

institutions will, as part of this reform, be transformed into

subsidies to building residents, to be used to purchase heat.

Apartment residents will pay for heating based on metered

consumption rather than on the basis of floor area, whichis the current practice. These policy changes should greatly

enhance consumer awareness of the cost of heating energy

and the value of energy savings and promote energy ef-

ficiency in buildings as well as strengthening the Chinese

economy.

A number of industries will benefit from this reform, in-

cluding makers and suppliers of indoor-temperature control

devices and control equipment for heating networks, radia-

tors, and other heat-production units. The reform will also

encourage development of insulation materials and technolo-

gies as well as other building materials for very cold and

cold zones. This change in the method by which heatingis paid for will focus attention on building-envelope perfor-

mance and create a substantial market for retrofits to im-

prove building energy performance.

As awareness of energy savings increases in Northern

China as a result of the heating payment reform, a ripple

effect is expected to be felt in other areas of the country.

Thus, this reform should promote building energy-efficiency

efforts and development of related industries throughout the

country.

3. Design standard for energy efficiency of residential

buildings in hot summer and cold winter zones JGJ

1342001

The hot summer and cold winter zone comprises 1.8

million km2, including 17 provinces, autonomous regions,

and municipalities, in the Yangtse River basin in Central

China. This area is well known for its dense population,

550 million people, and its highly developed economy;

it contributes 48% of Chinas gross domestic product

(GDP).

MOC approved standard JGJ 1342001 on 5 July 2001;

the standard took effect on 1 October 2001. The chief au-

thors of the standard were the China Academy of Building

Research and Chongqing Architectural University. Devel-

opment of the standard received financial support from the

China Sustainable Energy Program of the U.S.-based En-

ergy Foundation and technical support from LBNL and the

Natural Resources Defense Council (NRDC) in the US. The

Science and Technology Department, Norms and StandardsInstitute and the MOC Office for Energy Efficiency in Build-

ings organized the key authors of the standard to launch a

series of training courses on the standard. Some city govern-

ments also issued detailed local rules and regulations related

to the standard.

The standard includes sections on indoor thermal en-

vironments, energy-efficient building design, and heating,

air conditioning, and ventilation (HVAC) systems. The

standard covers energy-efficient design for new construc-

tion as well as retrofits and renovations in the hot sum-

mer/cold winter zone. Designers can use the standard to

determine building envelope thermal performance and the

energy-efficiency ratio of heating and air conditioningequipment required to produce a 50% reduction in heating

and air-conditioning energy consumption compared with

that of a base building under the same indoor thermal

conditions.

The standard offers two approaches to energy-efficient

design. One is prescriptive, based on the maximum al-

lowable heat-transfer coefficient for the building envelope

and the minimum required energy-efficiency ratio of the

heating and air conditioning equipment. The other (the

Comprehensive Index of Energy Efficiency in Buildings)

is performance based and gives the maximum allowable

heating and cooling energy consumption per square me-ter of floor area according to the numbers of heating and

cooling degree-days. The prescriptive approach is simple

to apply; the performance-based approach gives design-

ers flexibility. The heat-transfer process in conditioned

residential buildings in this climate zone is non-steady

state, so dynamic simulation software (DOE-2) is used to

calculate energy consumption for the performance-based

design approach. The team compiling the standard de-

veloped a software package based on DOE-2 that allows

designers, real-estate developers, and local government

officials to determine whether designs will to meet the

standard.

4. Design standard for energy efficiency of residential

buildings in hot summer and warm winter zone JGJ

752003

The hot summer and warm winter zone is located in

Southern China and includes most of Guangdong and

Guangxi provinces, the southern part of Fujian province,

Hainan province, Hong Kong, Macao, and Taiwan. The key

feature of this climate zone is a long summer and almost

no winter. The climate in this zone is hot and very humid


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S. Lang / Energy and Buildings 36 (2004) 11911196 1195

with intense solar radiation. This zone has a population of

150 million and contributes about 15% of Chinas GDP;

the area is known for its high standard of living and highly

developed economy, particularly in the Pearl River delta

area.

In 1998, 72 million m2 of building floor area, of which

50 million m2

were residential, were constructed in citiesin the hot summer and warm winter climate zone; 70% of

these buildings were constructed in Guangdong province.

Existing buildings in cities in this climate zone represent 810

million m2, of which 580 million m2 are residential. Because

of the rapid economic development in this area, construction

is expected to continue at a fast pace, particularly in shoreline

cities.

MOC approved standard JGJ 752003 in July 2003, to

take effect on 1 October 2003. The chief authors of the

standard were the China Academy of Building Research

and the Building Research Institute of Guangdong province.

The standard was developed with financial support from the

China Sustainable Energy Program of the US-based EnergyFoundation and technical support from LBNL and NRDC

in the US.

The standard targets a reduction in energy consumed

for air conditioning and heating (mainly air conditioning

in this zone). Like the standard described previously, this

standard also offers two approaches to energy-efficient de-

sign. In this case, the prescriptive approach stipulates the

same maximum allowable heat-transfer coefficients for the

building envelope as in the cold winter zone, but glazing

requirements (e.g. use of double glazing or thermally re-

flective or low-emissivity coatings) and shading coefficients

are stipulated based on orientations and window-to-wallarea ratios. The reason for these detailed glazing require-

ments is that the majority of summer cooling load is a

result of solar radiation that passes through window glass.

In addition, maximum allowable heat-transfer coefficients

are prescribed for lightweight walls and roofs (but not for

traditional mass walls e.g. masonry and roofs). If a design

does not meet the standards prescribed coefficients, the

designer should use the performance approach, which stip-

ulates relative allowable energy consumption per square

meter of floor area for heating and cooling (rather than

fixed consumption for a particular region). The performance

approach requires that the designer first calculate a ref-

erence budget of energy consumption based on the form

and orientation of the proposed design and the parameters

stipulated in the standards prescriptive approach. Then,

the designer calculates the energy consumption according

to the actual design, using changing K-values for enve-

lope and window glass performance until the buildings

energy consumption is less than or equal to that of the

reference budget. The incorporation of the two design ap-

proaches means that the standard can be applied to all

types of residential structures, including single-family res-

idences, low-rise buildings, and multi-story and high-rise

buildings.

5. Key barriers to promoting energy efficiency in

buildings in China and strategies to overcome these

barriers [3]

MOC and local governments have focused on energy

efficiency in buildings since the 1980s, and numerous stan-

dards and regulations as well as related incentive policiesand administrative rules have been issued. In addition, many

research projects in this area have produced valuable infor-

mation, and important products have been developed, ap-

plied, and commercialized. Many energy-efficient buildings

have also been built under the auspices of demonstration

projects.

By the end of 2000, the total existing floor area of urban

buildings in China was 7660 million m2, of which 4410

million m2 were residential buildings. Unfortunately, the

total floor area of residential buildings designed according

to energy-efficiency standards was only 180 million m2,

which represents only 8% of the total area of residential

buildings in cities in Chinas very cold and cold zones. Ex-cept in Beijing and Tianjin, most new residential buildings

that meet energy-efficiency standards are demonstration

projects.

1. The main barriers to energy efficiency in Chinas resi-

dential buildings are as follows:

2. Not all local government officials understand the urgency

and importance of energy-efficient design;

3. Energy efficiency laws and codes need to be refined;

4. There are insufficient economic incentives for energy-

efficient design and construction;

5. The administrative organization of energy-efficiency ef-forts needs to be improved; in particular, efforts to im-

prove the energy efficiency of buildings are not integrated

with efforts to improve the quality of wall construction

materials;

6. The existing method of heating payments provides no

incentive for building residents and developers of new

construction to focus on energy efficiency; and

The strategies for promoting energy efficiency in buildings

are:

1. Refine the descriptions of building energy efficiency in

the national code;

2. Establish an integrated administrative organization for

energy-efficiency efforts;

3. Establish government funding for energy-efficient build-

ings efforts based on national and local budgets from

the Ministry and Bureau of Finance and formulate

energy-efficiency incentive policies;

4. Promote reform of the heating payment system and deter-

mine a reasonable new heating payment policy that will

encourage energy efficiency and energy savings; and

5. Establish an evaluation and certification system for

energy-efficient technologies and products.


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6. Future prospects

According to the Chinese government timetable, energy-

efficiency design standards for residential buildings in all

climate zones should take effect by the end of 2003 (for

moderate zones, designers can use standards for neighbor-

ing climate zones). A revision of JGJ 2695 is the highestpriority because its design indices still lag behind those of

developed countries, and it addresses only central heating

systems and does not address air conditioning. In addition,

the Beijing municipal government is preparing to revise its

local energy-efficient buildings standard. This revised local

standard should result in a significant increase in energy

savings.

In the current standards, the key performance parame-

ters stipulated for windows are heat-transfer coefficients and

air tightness. These parameters are key in Northern China

where heating-season energy consumption dominates. How-

ever, in Central and Southern China where cooling loads are

the major contributors to residential energy consumption,the window performance requirements are somewhat differ-

ent. Similar to related American standards, in which win-

dow performance requirements are prescribed according to

climate zone, The Design Standard for Energy Efficiency of

Residential Buildings in the Hot Summer and Warm Winter

Zone has included a shading coefficient requirement.

Building energy efficiency is and will continue to be an

important aspect of a national strategy for managing energyresources, encouraging sustainable development and envi-

ronmental protection, and strengthening the Chinese econ-

omy and standard of living.

References

[1] Standard of Climatic Regionalization for Architecture GB 5017893.

[2] S. Lang, J.H. Yu, Energy conservation standard for space heating in

chinese urban residential buildings, Energy, The International Journal

18 (8) (1992) 871892.

[3] Center for Energy Efficiency in Buildings (MOC), Suggestions for

promoting energy efficiency in buildings in China. Seminar on energy

efficiency in buildings, MOC and US Department of Energy, Shanghai,

2000.

Documents

energy-efficiency standards for residential buildings in China