Improvement of Energy Efficiency in Commercial Buildings - Research Paper Example

Improvement and analysis of energy efficiency in commercial buildings Table of contents Hypothesis…………………………………………………………………………………3 Abstract…………………………………………………………………………………….3 Aim…………………………………………………………………………………………3 Introduction………………………………………………………………………………...3 Discussion and analysis ……………………….…………………………………………..4 i. Energy consumption in Hong Kong…………………………………………….4 ii. Analysis of the existing commercial buildings in Hong Kong………………….6 Conclusion………………………………………………………………………………...13 References…………………………………………………………………………………14 Hypothesis Energy use in commercial buildings in Hong Kong can be improved to increase efficiency and save on the cost of supplying energy. Abstract This paper investigates the improvement and analysis of energy in commercial buildings in Hong Kong. Building energy regulations have always been viewed as existing in a broad context whereby there exists a definite trend for the energy supply and the resulting demand in policy making. While the most fundamental economic policies of Hong Kong have an approach that tends to put more emphasis on the free market while the government takes a non partisan position whereby it does not interfere with the energy sector in any way. Hong Kong has come up with building energy codes that are applied in the commercial and other buildings and this has been triggered by the need to respond to the energy and environmental concerns. Recently, there has been a greater emphasis on development of highly efficient office buildings and therefore, there has been a great need to improve energy efficiency in commercial buildings. This area still remains under explored because of a number of reasons such as unavailability of cost data, lack of appropriate technologies that are cheap and also the misguided perception that the occupiers of the houses may be disrupted as a result of the improvements put into place to solve this problem. Aim This research paper aims to investigate the improvement and analysis of energy in commercial buildings in Hong Kong. Introduction Hong Kong is highly developed and has a high density of tall buildings. With the increasing awareness in the energy sector, it has become necessary to respond to environmental concern issues. In the past years, Hong Kong has been working towards developing programs that are energy efficient and conform to the building energy codes (Hui 1999). Since the energy crisis that occurred in the 1970s, Hong Kong has taken up a general approach towards solving the problems related to energy use in commercial buildings by developing some concepts and guidelines that govern the use of energy. Today, the use of energy in commercial buildings normally represent a portion of the amount of energy that is demanded by the community mainly electricity energy. Energy is very important to every society in its economic, environmental and social concerns and it plays a very crucial role in sustainable development. There is a growing demand for energy due to the increase in population, improved living standards, fast urbanization, and development of buildings. Efficiency is therefore driven by the high cost of energy and environmental concerns leading to increased energy prices and volatility, climate change and greenhouse gases emissions. Discussion i. Energy consumption in Hong Kong The energy indicators in Hong Kong are very low as compared to other parts of the world and this can be attributed to a number of factors including: the low population density in the country, the increase in the number of service oriented industries as compared to the manufacturing industries and the fact that there is not a single refinery in Hong Kong and in addition the culture of the local people in the use of public transport rather than driving their personal vehicles. The government of Hong Kong has ensured that several measures have been put into implementation so as to encourage the awareness of energy (Hui 1999). In this regard, the government came up with building energy efficiency regulations in the year 1995 so that they would act as the controls for ensuring that the commercial buildings that were constructed had energy efficient designs. Table 1: Building energy codes in Hong Kong(source: Hong Kong Energy Statistics 2010 Annual Report) Area of concern Date implemented Status Scope Building envelope(OTTV) July 1995 Mandatory Commercial buildings and hotels Lighting July 1998 Voluntary All buildings except industrial and medical buildings Air conditioning July 1998 Voluntary All buildings except industrial and medical buildings Electrical services February 1999 Voluntary All buildings except for special and industrial processing Lifts and escalators Mid -2000 Voluntary All buildings except for special and industrial processing A number of strategies have been put into place to encourage the use of the introduced building energy codes among the people and in this regard, in 1998 the government came up with a scheme of accrediting buildings that are compliant with the energy efficiency regulations. In this scheme, any building that be it an old or a newly constructed building that is fully compliant with the new codes is deemed eligible and suitable for accreditation as a building that is energy efficient compliant. The government issues a certificate of compliance to the owners of the building and its name is then entered into a government register that is specifically set aside for the purpose of registering all the energy efficiency compliant buildings. This scheme is mainly intended to create public awareness and also encourage more interest in having energy efficient buildings in the country. There was also an energy efficiency award that was held in the year 1997 and 1999 in Hong Kong and this also helps in achieving the intended goal of encouraging energy efficiency in commercial buildings. A labeling scheme for electrical appliances used in the buildings has also been developed and implemented and this provides consumers with information on the available opportunities for the energy efficiency. This scheme aims to develop products that are able to save energy and also allow consumer to make informed purchases. Currently, there are four types of appliances available in the market including devices such as: refrigerators, coolers, washing machines and fluorescent lamps. Buildings in Hong Kong constitute approximately 60 percent of the total energy that is required whereby most of it being consumed in the commercial buildings. The country’s economy has been growing at a very fast rate and the demand for both commercial and residential buildings has been on the rise. This has in turn caused an increase in the amount of energy that is being in these buildings and hence the need to have energy efficient buildings. Table 2: The energy requirements in Hong Kong (2010) Unit: MJ Commercial Residential Industrial Total Electricity 100, 2080(67%) 39,344(26%) 11080(7%) 150,705(100%) Town gas 11,389(41%) 15,272 (55%) 917(3%) 27,578 Electricity and town gas 111,669 54,616 11,997 178,285 % of the total FER 37.5% 18.4% 4.0% 59.9% Commercial buildings account for approximately 40% of the total energy consumed in Hong Kong which takes the largest share of the total energy required. This proves that there is need to come up with measures that will ensure that energy efficiency is achieved. Figure 1: Energy consumption by sector. ii. Analysis of the existing commercial buildings in Hong Kong The commercial buildings exist in several designs with each one of them having some unique aspects that have been put into place to ensure that energy efficiency is achieved. However, due to the fact that they have been built across different periods of time, they are compliant to different building standards and therefore there is need to have them improved for more efficiency. Figure 2 The figure above shows mid-town and west End offices whose design has been used for quite long. However, this type of commercial buildings only has the heating systems installed in them. The amount of carbon (iv) oxide emitted to the atmosphere remains very high. Figure 3 This type of commercial building has partially glazed air conditioning system and has been in existence since the early 1990s. The offices in this type of design are narrow and compliant with the building regulations that were enacted in the year 1990. Figure 4 This design is fully glazed and it has a deep planned air conditioning system. This type of design is compliant with the building regulations of the year 2002. Figure 5 The design is similar to that shown in figure 3 above but it has additional compliance to the building regulations. Figure 6: retail commercial building This type of building has a single storey with lighting, heating and air conditioning systems. The number of windows is limited and the warehousing space is also quite small. Figure 7: warehouse This type of commercial building has a single storey and has a lighting and heating system. The number of windows, the roof lights and warehousing space are quite small, and limited The buildings must be refurbished so that they meet the set market standards and therefore reduce the cost of operation incurred when carbon(iv)oxide is emitted. The market standards in this context refers to the minimum energy efficiency standard that a building could be refurbished to using a given technology while at the same time meeting the set regulations. The market standards however do not include any plant or their systems that have more energy efficiency as compared to earlier versions of the same that are available in the market. It is important to note that since the 1990s, commercial buildings have progressively become more efficient in terms of their energy consumption and this can be attributed to the enactment of energy laws that govern the building of commercial buildings and the standards that they must conform to. Lam 1998 states that the 1990s marked a very fundamental period in the activities that are aimed at achieving energy efficiency in Hong Kong and major policies and regulations were enacted. In the year 1991, The Efficiency advisory committee was set up by the government to oversee the use of energy in various sectors and formulate policies that would help them achieve their intended goal of achieving energy efficiency. A number of tools and programmes have been put into place thereafter so as to encourage all the stakeholders and the general public on the implementation of energy efficiency (Hui 1999). It has been observed that non air conditioned buildings tend to perform much better than air conditioned buildings and this awards them a better Energy performance Certificate (EPC) rating. It is expected that the continuous enactment of newer regulations in this sector to conform to the market standards and requirements will improve the EPC rating for most buildings. Research has shown that the EPC ratings for offices can be improved by an extra grade while at the same time incurring a minimum cost of at least 1% of the budget that has been set aside for the process of refurbishment of the building. Commercial buildings such as those shown in figure 2 and 3 above that were constructed more than 10 years ago can give the most cost effective opportunity to further enhance the EPC ratings of the buildings and cut down the amount of carbon (iv) oxide emitted to the atmosphere. In order to achieve an A-rated EPC in a building, it would require that the developer spends an additional 20% of the entire refurbishment budget for the market standard installations and this will in turn increase the cost of base refurbishment by a substantially wide margin. In additional, it would also require that a large photovoltaic array and a wide turbine is installed into the building so that an A rating on the EPC scale is achieved. However, it may not be possible to have all the available commercial buildings having an A-rated EPC but they can be made more efficient through a number of ways such as using boilers that are approximately 95% efficient, incorporating daylight controls into the buildings, improvement of the air tightness in the buildings, incorporating heating controls into the building and installing direct current drive fan coil units in the system. Hong Kong has some energy efficiency codes that are employed in the building sector to ensure that minimum energy is consumed while at the same time ensuring that minimal pollution is experienced. These include: a) Building energy efficiency regulation cap 123 subs Leg.M [implemented in July 1995]. b) Using overall thermal transfer value (OTTV) method for building envelope design control. It is applied mainly to commercial buildings and hotels. It has been revised in 2000 and 2011. Figure 8: a typical building and the generation of the OTTV The general OTTV equation for any region is given by: The OTTV equation for Hong Kong is: The OTTV equation for Hong Kong has some unique characteristics which make it different from the general equation. In the above equation we can note that the glass conduction term has been omitted, there has been an introduction of the solar absorptivity and external shading multipliers. A number of building codes have been introduced in Hong Kong to improve energy efficiency in commercial buildings and these codes include: a) Lighting b) Air conditioning c) Electrical d) Lifts and escalators e) Performance based code. The measures that have been applied to ensure that energy is used efficiently in commercial buildings and this usually results into a reduction in the amount of energy consumed as well as optimal performance of the building. Some of the measures taken include: a) Adoption of a no cost or low cost approach and this does not require any appraisal. b) Medium cost approach which requires only a simple payback calculation c) High capital cost which requires a detailed design and an investment that is in full appraisal. In Hong Kong, the energy consumption in commercial buildings in influenced by a number of factors which include: a) Building services: This usually encompasses factors such as the fuel type, the type and size of systems installed in the commercial buildings, the available plant controls and also the plant efficiency and operating regime. b) The building envelope which revolves around issues related to the size of the building, the shape and materials used in the construction, ventilation available and the location and orientation of the building. c) Human factors: some of the human factors that influence the energy consumption in a building revolve around factors such as the comfort requirements of the occupants, the management and maintenance operations on the building and also the access controls available. The stipulated measures have been implemented and from the results that have been realized, a number of benefits have been achieved and in particular, the cost incurred from the energy consumption has greatly reduced. Some of the benefits realized include: a) There has been an improvement in the building’s design and operation activities within the commercial buildings have become more efficient. b) The working environment has been seen to have greatly improved and the occupants are much more comfortable in the new environments. c) The cost incurred in catering for the energy required in the buildings has been greatly reduced. d) The market value for the buildings has seen to improve and there is more demand for modern buildings that conform to the new building standards. e) The amount of carbon (iv) oxide emitted to the atmosphere has been reduced by a great margin as result of consumption of finite fossils fuels. However, a number of barriers still exist in the implementation of the measures put into place to achieve an energy efficient environment including setbacks such as insufficient information and finances for use in improvement of the current structures, lack of harmonious incentives among the developers and the tenants have different choices of lifestyles and these hamper the implementation of the set measures achieve an energy efficient environment, the key stakeholders such as developers, architects, facility managers and the tenants must all play their roles effectively and this will ensure that we have a harmonious implementation approach. However, it is possible to overcome the current market barriers in the implementation of an energy efficient environment and this can be achieved by building houses that are properly certified and conforming to the set regulations, the developers should adopt a policy that gives the best practice in buildings and must have extremely low energy consumption that is zero rated, policies should be set up to raise the energy efficiency of buildings to a point that is above the minimum required benchmark and finally the government should adopt a policy that ensures that energy savings contracting is adhered to by all developers. Conclusion From the analysis and discussions carried out, it is evident that there is need to improve energy efficiency in the commercial buildings as this will greatly reduce the amount of carbon(iv)oxide emitted to the atmosphere. The current regulations are not sufficient enough and the government should involve all the stake holders so as to come up with the necessary legislations that will ensure that energy efficiency is achieved in the commercial buildings. The Energy performance Certificate(EPC) for the commercial buildings can be improved through a process that is cost effective but the developers and all the other stakeholders must be ready to plough in some financial contribution towards achieving efficiency in the buildings. References Building Authority. 1995. Code of Practice for Overall Thermal Transfer Value in Buildings 1995. Hong Kong: Building Authority, April. CSD. 1999. Hui, S.C.M. 1999. "Recent Developments and Analysis in Energy Efficiency in Buildings in Hong Kong". Energy Efficiency in Buildings 1999 (1): 6-10. (In Chinese) Janda, K.B. and J.F. Busch. 1994. "Worldwide Status of Energy Standards for Buildings". Energy 19 (1): 27-44. Hong Kong Energy Statistics Annual Report 1998 Edition . Hong Kong:Census and Statistics Department (CSD), Hong Kong. EMSD. 1998a. Code of Practice for Energy Efficiency of Lighting Installations . 1998 edition. Hong Kong: Electrical and Mechanical Services Department (EMSD), the Government of the Hong Kong Special Administrative Region. EMSD. 1998b. Guidelines on Energy Efficiency of Lighting Installation. 1998 edition. Hong Kong: Electrical and Mechanical Services Department (EMSD), the Government of the Hong Kong Special Administrative Region. Dr. Sam C. M. Hui, Building Energy Efficiency in Hong Kong: How High We Can Go? Department of Mechanical Engineering, The University of Hong Kong. Hui, S.C.M. 1997a. "Study of Building Energy Efficiency and Engineering & Construction Standards". In Proc. of the Mainland-Hong Kong Engineering & Construction Standards Exchange Seminar (Hong Kong Section), 14-15 April 1997, Beijing, China, 22.1-22.10. (In Chinese) Hui, S.C.M. 1997b. "Overall Thermal Transfer Value (OTTV): How to Improve Its Control in Hong Kong". In Proc. of the One-day Symposium on Building, Energy and Environment, 16 October 1997, Shangri-la Hotel, Kowloon, Hong Kong, 12-1 to 12- 11. Lam, J.C. and S.C.M. Hui. 1996. "A Review of Building Energy Standards and Implications for Hong Kong". Building Research and Information 24 (3): 131-140. Lam, R.S.F. 1998. An Analysis of the Policy of Energy Efficiency and Conservation in Hong Kong in the 1990s. Master of Public Administration (M.P.A.) thesis, University of Hong Kong. Read More