Sample4 Overuse of Airconditioning

Running head: OVERUSE OF AIR-CONDITIONING SYSTEM 1

Overuse of air-conditioning system in Hong Kong: harms and possible solutions

The Hong Kong government always recommends an indoor temperature at 25.5°C, in

order to strike a balance between the impact of air-conditioning system on

environment and personal comfort. However, what is the real situation? According to

the 2011 record of Green Sense, an environmental organization in Hong Kong, it

received 37 low temperature reports from June to August, complaining about the

exceptionally low indoor temperature, most around 19 to 22 degrees. And this year

the complaints are even concerned with university buildings; for instance, Hong

Kong University was reported to have an indoor temperature as low as only 18

degrees (馮晉研 , 2012). Actually even without any data, the strange phenomenon

that a large number of people wear long-sleeved cardigans while using air-conditioned

rooms in such a hot summer time demonstrates that the air-conditioning system is

now severely overused. Therefore, this essay aims to analyze the harms and reasons

and then try to propose some possible solutions: first, to arouse public awareness

about the seriousness of this issue; and second, to improve the design of the

air-conditioning system.

The overuse of air-conditioning system does harm to us in the following aspects:

personal discomfort, energy consumption and environmental impacts. For personal

discomfort, everyone knows that it is not easy to adjust to the big gap between

temperatures of often more than ten degrees when a person goes indoors. Serious

OVERUSE OF AIR-CONDITIONING SYSTEM 2

thermal discomfort may even lead to the Sick Building Syndrome (SBS), with

symptoms including fatigue, drowsiness, dry throat, eye irritation and so on. And

according to research, more than half respondents suffered at least one of these

symptoms twice a week (Chen & Chang, 2012). As for energy consumption, the

electricity depleted by air conditioners in 2010 accounted for 29% of yearly

consumption, still the biggest part of annual electricity depletion, though slightly

better than 35% in 2000 (Electrical & Mechanical Services Department [EMSD],

2012). In terms of the impacts on environment, air conditioners deteriorate global

warming both by the release of refrigerants and by the emission of carbon-dioxide

related to the energy consumed. Moreover, release or leakage of refrigerants

containing chlorine, bromine, or other halogens accelerates ozone depletion (Calm,

2002). And chillers of air conditioners are not really producing coolness but actually

discharging the indoor heat to the external environment, thus increasing the outdoor

air temperature and heating Hong Kong up.

Before we propose some feasible solutions to the overuse problem, it is better to have

a deeper understanding of why Hong Kong people are used to setting such a low

temperature. In the first place, a great number of people believe that the

air-conditioning system can contribute to the purification of air. However, according

to research comparing air-conditioned and non-air-conditioned markets, the operation

of air-conditioning system does not significantly reduce the levels of air pollutants

(Guo, Lee, & Chan, 2004) and on the contrary, even elevates bacteria concentrations.


Another reason is that, a commercial society and developed district as Hong Kong is,

office employees and government officials are always required to dress formally at

work. And then it seems a low temperature is inevitable. However, these years a

campaign of dressing casually is launched by the Japanese government to save energy

(Hosaka, 2011). So maybe it is also the time to consider loosening the tight tie of our

commercial dressing rules since we are still under such an austere environmental

situation. And government officials can set a good example for the public by

emulating the casually-dressed Japanese officials.

Apart from the dressing style of elite class and white-collar bourgeois, the most

fundamental method to tackle the problem is without doubt raising public awareness

over this issue. The Hong Kong government has already introduced a mandatory

Energy Efficiency Labelling Scheme (EELS) through the Energy Efficiency

(Labelling of Products) Ordinance, to distinguish air-conditioners of different

energy-saving levels, and thus further facilitating the public in choosing energy

efficient appliances (GovHK, 2012). And environmental organizations are making

further contributions. For example, Green Sense holds an annual activity “Hong Kong

No Air Con Night”, and this year over seventy thousand households and university

students pledged to switch off their air-conditioning systems on September 27th, from

7 pm to 7 am (Green Sense, 2012). We can see the improvement of public

environmental awareness through the data of declined air-conditioning using in the

past ten years, while further efforts are needed (EMSD, 2012). For example,


organizing regularly held lectures is feasible to remove public misunderstandings.

Moreover, China will earmark 14 billion RMB to subsidize the purchases of energy

saving products, of which the air-conditioner is included (Mu, 2012). Taiwan also

promised early this year each purchase of air-conditioners with Energy Efficiency

Standard class 1 or 2 would be granted a subsidy of NT$2000 (about HK$530) (Hong

Kong Trade Development Council [HKTDC], 2012). Hong Kong policy makers can

also consider implementing similar plans to encourage a public habit of energy-saving.

After all, it is already a habit for Hong Kong people to keep a low indoor temperature,

and we need to solve this problem fundamentally through the public ways.

Another way is to improve the design of air-conditioning system according to relevant

thermal research to make it more sensitive to the environmental changes, so that it

conditions the indoor temperature at a reasonable degree, consumes less energy,

releases less carbon dioxide, and brings more comfort to users. For example, Mui and

Chan of the Hong Kong Polytechnic University conducted research and experiments

(2003) to reveal the approximate connection between adaptive comfort temperature

(ACT) and outdoor temperature. The regressed equation is ,

where Tn is the adaptive comfort temperature and To is the outdoor temperature. And

they estimated that implementing this model could reduce energy consumption of

about 7% (Mui & Chan, 2003). Also Wong and Mui (2009) analyzed the related

factors in air-conditioned offices in Hong Kong: indoor temperature, humidity and air


velocity, and established a model to balance energy consumption and thermal comfort

to improve productivity. A number of research and experiments such as those two

above aim to establish a model for better use of air-conditioning system that can be

applied to the subtropical and humid climate of Hong Kong. We can improve the

design of the air-conditioning system so that it automatically changes the temperature

according to thermal models, and it would be better for us users as well as the

environment.

As we can see through the research data and our own observation, the extremely low

indoor temperature in Hong Kong is not necessary, and even does harm to our

environment as well as every individual. Now it is high time we strived to improve

the situation of air-conditioner overuse. We can approach this target basically by two

methods: one is to arouse the public environmental awareness, and the other is to

improve the design of air-conditioners. The technical solution is significant and also

inevitable along with the rapid development of science and technology, while the

public environmental awareness is the more fundamental factor to rectify the poor

habit of setting a low temperature since it is a public issue and joint efforts are

desperately needed to combat this problem ultimately.


References

Calm, J. M. (2002). Emissions and environmental impacts from air-conditioning and refrigeration systems. International Journal of Refrigeration, 25(3), 293–305. doi: 10.1016/S0140-7007(01)00067-6

Chen, A., & Chang, V. W. C. (2012). Human health and thermal comfort of office

workers in Singapore. Building and Environment, 58, 172–178. doi: 10.1016/j.buildenv.2012.07.004

Electrical & Mechanical Services Department (EMSD). (2012). Hong Kong Energy

End-use Data 2012. Retrieved from http://www.emsd.gov.hk/emsd/e_download/pee/HKEEUD2012.pdf

Green Sense. (2011). Freezing Indoor Air Conditioning Temperature during Hotter

Summer. Retrieved from http://greensense.org.hk/en/2011/08/%E4%BB%8A%E5%B9%B4%E6%8E%A5%E6%9C%80%E5%A4%9A%E5%B8%82%E6%B0%91%E6%8A%95%E8%A8%B4%E3%80%80%E6%96%B0%E3%80%8C%E5%9F%8E%E5%B8%82%E9%9B%AA%E6%88%BF%E3%80%8D-%E9%85%92%E5%BA%97-%E6%B3%95%E5%BA%AD/

Green Sense. (2012). 70000 household pledged to join the 3rd Hong Kong No Air

Con Night held by Green Sense. Retrieved from http://noaircon2012.blogspot.hk/2012/09/7-70000-household-joined-3rd-hong-kong.html

GovHK 香港政府一站通. (2012). Mandatory Energy Efficiency Labelling Scheme.

Retrieved from http://www.gov.hk/en/residents/environment/energy/mandatorylabel.htm

Guo, H., Lee, S. C., & Chan, L. Y. (2004). Indoor air quality investigation at

air-conditioned and non-air-conditioned markets in Hong Kong. Science of The

Total Environment, 323(1-3), 87–98. doi: 10.1016/j.scitotenv.2003.09.031

Hong Kong Trade Development Council. (2012). Taiwan's appliance subsidy a global

hit. Retrieved from http://economists-pick-research.hktdc.com/business-news/article/International-

Market-News/Taiwan-s-appliance-subsidy-a-global-hit/imn/en/1/1X000000/1X07XB4Z.htm


Hosaka, T. A. (2011, May 6). Japan asks workers to dress cool to save energy. USA

Today. Retrieved from

http://usatoday30.usatoday.com/money/world/2011-06-05-japan-dress-cool_n.htm Mu, X. (2012). China to subsidize energy-saving desktops, air conditioners [online

news]. Retrieved from http://news.xinhuanet.com/english/china/2012-09/09/c_131838648.htm

Mui, K. W. H., & Chan, W. T. D. (2003). Adaptive comfort temperature model of

air-conditioned building in Hong Kong. Building and Environment, 38, 837–852. doi: 10.1016/S0360-1323(03)00020-9

Wong, L. T., & Mui, K. W. (2009). Efficiency assessment of indoor environmental

policy for air-conditioned offices in Hong Kong. Applied Energy, 86(10), 1933–1938. doi: 10.1016/j.apenergy.2008.12.012

馮晉研. (2012, September 24). 港大課室勁凍師生投訴 [Hong Kong University’s teachers and students complain about the extremely low temperature in classrooms]. 文匯報 [Wen Wei Po]. Retrieved from

http://pdf.wenweipo.com/2012/09/24/a18-0924.pdf

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Sample4 Overuse of Airconditioning