Journal of Power and Energy Engineering, 2013, 1, 16-24 Published Online October 2013 (
Copyright © 2013 SciRes. JPEE
The Effects o f Future C l i m ate Change on Energy
Consumption in Residential Buildings in China
D. H. C. Chow, M. Kelly, J. Darkwa
Centre for Sustainable Energy Technologies (CSET), University of Nottingham, Ningbo, China.
Received August 2013
China is currently going through a phase of rapid mass urbanisation, and it is important to investigate how the growing
built environment will cope with climate change, to see how the energy consumption of buildings in China will be af-
fected. This is especially important for the fast-growing cities in the north, and around the east and south coasts. This
paper aims to study the effects of future climate change on the energy consumption of buildings in the three main cli-
mate regions of China, namely the “Cold” region in the north, which includes Beijing; the “Hot Summer Cold Winter”
region in the east, which includes cities such as Shanghai and Ningbo; and the “Hot Summer Mild Winter” region in the
south, which includes Guangzhou. Using data from the climate model, HadCM3, Test Reference Years are generated
for the 2020s, 2050s and 2080s, for various IPCC future scenarios. These are then used to access the energy perform-
ance of typical existing building s, and also the effects of retrofitting them to the standard of the current building codes.
It was found that although there are reductions in energy consumption for heating and cooling with retrofitting existing
residential buildings to the current standard, the actual effects are very small compared with the extra energy consump-
tion that comes as a result of future climate change. This is especially true for Guangzhou, which currently have very
little heating load, so there is little benefit of the reduction in heating demand from climate change. The effects of retr o-
fitting in Beijing are also limited, and only in Ning bo was the effect of retrofitting able to nu llify the effects of climate
change up to 2020s. More improvements in building standards in all three regions are required to significantly reduce
the effects of future climate change, especially to beyond 2020s.
Keywords: Climate Change; Energy Consumption; Residential Buildings; Retrofitting; Urbanisation
1. Introduction
Over the last 30 years, the rapid growth in the Chinese
economy has led to a drastic increase in energy con-
sumption, where the building sector is responsible for
around 27.5% of the national total energy consumption
[1-3]. Zhong has shown that this percentage could to rise
to 40% over the next 20 years as more buildings will be
constructed [4]. This together with occupants demanding
a higher level of indoor comfort will lead to a steeper
increase in heating and cooling loads. At the end of 2010,
the whole of China has over 43 billion square metres of
constructed area, however, only 4% - 5% meet the na-
tional building energy standards, and the other 95% -
96% are classified as “intensive energy consumers” [5,
In China, the lifespan of most buildings is short even
by modernist standards. This high turnover rate, along
with the recent construction boom, has resulted in an
existing building stock that is fairly young. Zhu and Lin
[7] project that by 2015, half of China’s existing building
stock will have been built after 2000. Chen Huai, director
of the policy research centre at the Ministry of Housing
and Urban-Rural Development, stated himself in 2010
that “Only those homes built after 1999 are likely to be
preserved in the longer term” due to perceived safety and
functionality deficits in older buildings [8].
Effects are being made by the government to reduce
the amount of energy consumed by buildings in China
with more and more stringent building codes for residen-
tial, commercial and public buildings. However, despite
the comparatively high rates of construction and demoli-
tion, most buildings in China do not comply with the
latest national building codes. This paper aims to inves-
tigate the b enefits of retrofittin g existing reside ntial build-
ings to the standard of the current building code in cities
(Beijing, Ningbo and Guangzhou) in three of China’s
main climate zones, and see if retrofitting to the current
standard can nullify effects of future climate change in
these regions in the next 100 years. Data from the climate
prediction model, HadCM3, will be the impacts of cli-
The Effects of Future Climate Change on Energy Consumption in Residential Buildings in China
Copyright © 2013 SciRes. JPEE
mate change in the next 100 years will also be investi-
Climate Zones in China
There are five main climatic zones in China: “Severe
Cold”, “Cold”, “Hot Summer and Cold Winter”, “Mod-
erate”, and “Hot Summer and Warm Winter”, as shown
in Figure 1 [9]. They have distinctive characteristics, and
therefore separate national building codes. This paper
will investigate the situation in the “Cold” zone by using
weather data for Beijing, the “Hot Summer and Cold
Winter” zone with the city of Ningbo, and the “Hot Sum-
mer and Warm Winter” zone with the city of Guangzhou.
2. Climates in Beijin g, N in gb o and
The cities of Beijing, Ningbo and Guangzhou were se-
lected to represent situations in the three differe nt climate
zones in China. The buildings in each zone have very
different heating and cooling needs. For example, Guang-
zhou in the “Hot Summer Warm Winter” zone has very
little heating demand, as its winters are relatively mild.
Ningbo, on the other hand, has significant heating and
cooling loads, but overall, it can be considered relatively
mild over the whole year. Beijing also has hot summers,
especially around August and early September. Winter
temperatures can be very cold. The changes in the next
100 years due to climate change for the three climate
zones are also significantly different.
2.1. Current Climates
Long running series of real observed data from weather
stations in the three cities were not available for this
study, so in-depth study of the ch aracteristics of different
weather parameters could not be conducted. However,
data can be extracted from the existing Test Reference
Years, from the Energy Plus program. Table 1 shows the
average monthly values for daily maximum and mini-
mum t empe rat u re s for the three selected cities.
Figure 1. Climate zones in China.
Table 1. Current monthly average Tmax and Tmin for Beijing,
Ningbo and Guan gzhou.
Month Average Daily Max Temp (˚C)
Average Daily Min Temp (˚C)
Jan 6.6 8.2 18.3 7.3 1.2 10.7
Feb 3.1 8.9 18.1 11.5 2.5 11.1
Mar 6.8 11.5 22.2 2.5 5.9 15.2
Apr 9.9 20.2 25.9 5.7 10.8 19.9
May 16.3 23.3 30.1 8.3 16.8 22.7
Jun 23.6 27.1 30.9 11.5 21.5 24.7
Jul 27.6 30.2 33.4 20.6 24.2 25.7
Aug 34.6 29.2 32.3 29.1 24.7 25.3
Sep 35.0 25.0 31.8 22.7 20.0 24.1
Oct 21.3 22.4 28.9 13.2 16.8 20.8
Nov 12.8 16.2 25.3 0.1 8.8 16.3
Dec 7.6 10.0 21.3 4.1 1.7 11.3
aBJ denotes Beijing; bNB denotes Ningbo; cGZ denotes Guangz hou.
2.2. Future Climate Change
The Hadley Centre model (HadCM3) [10] is used to pro-
vide future climate data for this study. HadCM3 is a
global climate model developed at the Hadley Centre of
the Met Office in the UK. It is a Coupled Atmosphere-
Ocean General Circulation Model (AOGCM), in which
the globe is divided into grid boxes, each measuring
2.50˚× 3.75˚. The gridboxes used in this paper are grid-
box numbers 1952 (wh ich encloses the area with latitude
from 38.75˚N to 41.25˚N, and longitude from 114.375˚E
to 118.125˚E, and includes the city of Beijing), 2337
(which encloses the area with latitude from 28.75˚N to
31.25˚N, and longitude from 118.125˚E to 121.875˚E,
and includes the c ity of Ningbo and Shanghai), an d 2623
(which encloses the area with latitude from 21.25˚N to
23.75˚N, and longitude from 110.625˚E to 114.375˚E.
and includes the city of Guangzhou). Fig ure 2 sho ws the
extent of the gridbox for Ningbo. Unlike weather data
from typical weather years, HadCM3 only provide daily
values for parameters such as maximum, minimum and
average temperatures, humidity, wind speed and down-
ward short-wave flux (solar radiation), based on 4 main
future scenarios on carbon emissions, A1F, A2, B2 and
B1 [11]. For example, the A2 scenario describes a very
heterogeneous world where slow and fragmented eco-
nomic growth is assumed, together with a continuation of
population growth and continued increase in CO2 emis-
sion into the twenty-first century [12].
2.3. Compilation of Future Test Reference Yea rs
Test Reference Years for Beijing, Ningbo and Guang-
zhou were constructed using the “morphing method” [13],
which uses differences between monthly averages from
“historical pe r iods” a nd “ future pe ri ods ” , a nd impose these
The Effects of Future Climate Change on Energy Consumption in Residential Buildings in China
Copyright © 2013 SciRes. JPEE
Figure 2. Area covered by gridbox 2337 of HadCM3.
onto existing Test Reference Year. For this study, data
from HadCM3 are separated into four periods: 2000s
(which includes all data from 1990-2009); 2020s (which
includes data from 2010-2039); 2050s (which includes
data from 2040-2069) and 2080s (which includes data
from 2070-2099), and the average monthly temperatures
under the A2 scenario from resulting TRYs for Ningbo is
shown in Figure 3.
2.4. Changes in Temperature and Solar
For the three selected gridboxes from HadCM3, the in-
creases in temperature are steady from 2000s to 2020s,
and then subsequent increases to 2050s and 2080s. How-
ever, there are significant differences in the changes be-
tween the gridboxes. For the Beijing gridbox, the in-
creases are more rapid for daily maximum temperature
values, and also faster for the summer months than the
winter months. The opposite is true for the Guangzhou
gridbox, where rises for daily minimum temperatures are
faster, and increas es are also b igger for the w inter months.
For the Ningbo gridbox, the rises are similar between
months and also between daily maximum, average and
minimum values.
For future changes in solar radiation, there are reduc-
tions in all three gridboxes, particularly during the win ter
period. For the Guangzhou gridbox, there is also signifi-
cant and continuing decrease in solar radiation in the
summer months. For the Beijing and Ningbo gridboxes,
there are slight increases in summer, but the increases are
lower than the decreases in winter. The general increases
in summer could be explained by a possible reduction in
cloud cover in the future. However, as the future atmos-
phere becomes more turbid, the general trend of solar
radiation in the future is one that is decreasing. Figure 4
shows the changes in daily maximum temperature and
solar radiation changes in the Guangzhou gridbox from
2000s to 2020s, 2050s and 2080s.
3. Methodology
The study used a typical residential building in the three
cities and ran the whole year heating and cooling de-
mands for the existing building specifications as well as
standards complying with the latest building codes. This
was conducted for current Test Reference Years and also
Test Reference Years for 2020s, 2050s and 2080s, under
various future sce na rios.
3.1. Typical Building Used for Study
This study targets a mid-size multi-family residential
apartment complex built in 2003, the first year that resi-
dential building energy codes were adopted in all three
study cities. The selectio n of this p articu lar bu ilding for m
is intended to be both realistic and str ateg ic. A cheap and
quick-to-construct answer to increasing housing needs,
these types of buildings are ubiquitous in Chinese cities.
These apartment buildings are in a grey areaof cultura l
The Effects of Future Climate Change on Energy Consumption in Residential Buildings in China
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Figure 3. Average monthly temperature for current and future TRYs for Ningbo (A2 scenario).
Figure 4. Changes in daily maximum temperature and solar radiation under the A2 scenario for Guangzhou.
valuealthough lacking in the prestige of historic struc-
tures or the glamour of new designs, they form the foun-
dation for daily urban life for many people.
Although not the worst-performing building type, the
early building codes within which these buildings were
constructed are quite low compared even to current codes
a decade later, and they are likely to be inadequately
prepared for future climate change. Additionally, build-
ings constructed in the midst of the construction boom,
which focused on speed over quality, are now showing
severe maintenance problems which require refurbish-
ment and repair. Figur e 5 shows an iso metric view of the
1 2 3 4 5 6 7 8 910 11 12
Average Monthly Temperature
Average Monthly Temperature for current and future TRYs for Ningbo (A2 Scenario)
Current TRY
Changes in Solar Radiation (W / m
Changes in Temperature (deg C)
Guangzhou (A2 Scenario) changes in Tmax and Solar Radiation
2020s DSWF
2050s DSWF
2080s DSWF
2020s Tmax
2050s Tmax
2080s Tmax
The Effects of Future Climate Change on Energy Consumption in Residential Buildings in China
Copyright © 2013 SciRes. JPEE
Figure 5. Isometric view of the study building.
building type be i ng studied.
The building and project site are both designed to be
as generic as possible to facilitate high levels of compar-
ison between the three study cities. The buildings sur-
rounding the project site are a composite of similar sites
in each of the three cities, and represent a primarily-res-
idential neighbourhood with buildings of different ages.
The apartment complex itself, located on the corner of
the main streets, consis ts of nine identical build ings with
a north-south orientation. Each building is eight stories
tall and contains sixty-four apartments. Based on the av-
erage values from surveys of similar apartment buildings
conducted by Chen et al. [14,15], Gu et al. [16], and Hu
et al. [17], each apartment has 85 m2 of floor space, in-
cluding two bedrooms, a bathroom, and a living room.
For realism, it is assumed that the balcony space was
originally designed as a balcony, and was later enclosed
to provide additional living space in the apartment and
raise its marketability; this is a common refurbishment
strategy [18]. One building in the apartment complex,
highlighted in blue in Figure 6 was used for the evalua-
tion of retrofitting options.
3.2. Specification for “Current” Buildings
Although Rousseau and Chen [19] describe older apart-
ment buildings as having solid brick construction with
concrete floors, bricks were banned for construction in
1999 due to the increasing environmental impacts asso-
ciated with their demand. Fernández [20] and Huang, et
al. [21] report that most multi-family residential build-
ings constructed in the past two decades are made from
reinforced concrete. The demand for concrete in China’s
building sector in general [22] also lends confidence that
reinforced concrete is the most representative material
for this building type. Generally, the assemblies selected
for the study building are adapted directly from the ma-
terial intensities for residential buildings compiled by
Figure 6. Theoretical site for the study building.
Fernández [20], with confirmation or modifications as
needed from other studies and based on building code
requirements for each city. Wang, et al. [23], Aden, et al.
[24], and Chen, et al. [25] report on the use of expanded
polystyrene (XPS) insulation in buildings, and where in-
sulation is required to meet the building code, XPS insu-
lation was added in 10 mm increments until the maxi-
mum compliant U-value was reached. All material prop-
erties were adapted from Anderson [26].
For windows and the glazed balcony doors, double-
paned glazing with aluminium frames were assumed for
Beijing and Ningbo, as single-glazed panes do not meet
the building codes. Guangzhou’s residential build ing code
does not specify an insulation level for glazing, but in-
stead mandates shading coefficients as solar gains are
more important than thermal loss e s in its warmer cli mate.
Thus, for Guangzhou, single-pane reflective glass was
assumed for all glazing. Figure 7 summaries the con-
struction specifications for th e build ing in each city.
3.3. Specification for Renovated Buildings
While the most recent residential building codes in China
are stricter than those in 2003, they have nonetheless
been developed based on historic climate knowledge.
While lower current energy consumption may indicate
greater climate resiliency, it cannot be taken for granted
that buildings built to current codes will maintain higher
performance levels under future conditions. To compare
the climate vulnerability of the study building against a
newer structure, an equivalent but code-compliant build-
ing was also modeled. This building represents both a
building of the same size constructed in 2014, which
could replace the existing structure entirely, and the study
building if it were retrofitted to meet current codes with-
out any other measures. Table 2 lists the envelope re-
quirements which have improved since 2003; all other
elements of the existing building remain compliant. Be-
cause no new residential code has yet been published for
The Effects of Future Climate Change on Energy Consumption in Residential Buildings in China
Copyright © 2013 SciRes. JPEE
Figure 7. Construction speci fi cat ions for the study building i n each city.
Table 2. Updated envelope element requireme nts i n t he most recent building codes.
Element Beijing Ningbo Guangzhou
existing J12070-2012 existing JGJ1342010 existing DBJ15-51-2007
(W/m2K) 2.7 1.8 - - 6 3.5
Window SC - - 18.1 -11.5 - -
(W/m2K) 0.54 0.35 0.8 0.45 - -
Ext. Walls
(W/m2K) 0.76 0.40 1.34 1.0 - -
Ground Floor
(W/m2K) 0.53 0.45 - - - -
the “Hot Summer Warm Winter” region, the most recent
public building standard is used as a substitute represen-
tation of current practices.
The comfort range where no heating and cooling
would be supplied to the building was set as 18˚C to
26˚C for all three cities.
4. Results
Figure 8 shows the monthly space conditioning (heating
and cooling) requirements for the residential building
under the current climate, and also for 2020s, 2050s and
2080s under the A2 scenario. Figure 9 shows a compar-
ison between the predicted heating and cooling energy
consumption of the existing and equivalent code-com-
pliant buildings, under the A2 scenario, together with the
most severe A1F and the least severe B1 scenarios.
While the new code results in some stabilization, ulti-
mately the underlyin g patterns of increasing ris k are pre-
served. In Guangzhou, the code improvements lower
cooling loads by 6.2%, rising to a maximum of 10.7% by
2080 in the A1F scenario and 8.5% in the A2 scenario.
For the building in Beijing, the results are mixed, with a
less than 1% reduction in heating loads under the A1F
and A2 scenarios. In the B1 scenario, heating loads are
predicted to increase compared to the existing building.
Cooling loads follow an opposite pattern, with a decrease
in cooling energy under the B1 scenario and little effect
otherwise. The effect of reducing direct solar gains in the
most recent “Hot Summer Cold Winter” zone code in-
creases heating loads by 9.7% in 1980. However, as ex-
isting cooling loads are reduced by 46.1% and 2080
cooling loads are reduced by 31.0% - 34.0 %, the result is
largely positive when viewed over the entire centur y.
5. Conclusions
This paper studied the effects of retrofitting residential
buildings in cities in three major c limate zones of China,
from building standards set in 2003 to the current build-
ing codes, and seeing how this would perform under cli-
mate change in the next 100 years. Guangzhou, with no
heating demand in its warm winters, does not benefit
from the reduced heating demand with climate change,
and with retrofitting to the current code, there is only a
small amount of reduction in cooling loads, which is not
The Effects of Future Climate Change on Energy Consumption in Residential Buildings in China
Copyright © 2013 SciRes. JPEE
Figure 8. Predicted monthly heating and cooling energy
consumption at each horizon year under the A2 scenario.
enough to counter the effects of future climate change,
regardless of which scenario the world follows in the
future. For the case of Beijing, the differences between
existing and retrofitted buildings are not great, for both
heating and cooling demands, and there is greater in-
crease in cooling load than the reduction in heating load,
meaning that future energy consumption in the future
will increase sign ificantly, even with retrofitted buildings.
As for Ningbo, this showed the biggest reduction in
energy consumption with retrofitting. For both heating
and cooling loads, a retrofitted building will have lower
energy demands in 2020s compared with the existing
building standard under the current climate. Depending
on the scenario, this benefit may even extend to the
2050s for cooling demands.
With all three cases, it is clear from the results that the
current building standards will not be able to nullify the
effects of future climate change, and more studies are
Figure 9. Projected heating and cooling loads of the existing
(blue and red) and equivalent code-compliant (grey) build-
ings under all three scenarios.
The Effects of Future Climate Change on Energy Consumption in Residential Buildings in China
Copyright © 2013 SciRes. JPEE
required to investigate optimum building standards for
each different climate region in China, which are also
economically feasible. This study has not taken the ef-
fects of urban heat islands, which will make the quest for
producing low-energy buildings even more challenging.
6. Acknowledgements
D.C. would like to thank Dr John Parkinson of the Uni-
versity of Manchester for extracting the HadCM3 files
for the grid boxes 1952, 2337 and 2623.
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