Hong Kong is a high-rise and high-density metropolis with a semitropical clime. At present, Hong Kong does non as yet do important usage of renewable resources to run into its energy demands. Lack of inducements and deficit of land and infinite are the cardinal factors restricting the deployment of renewable energy systems ( Hui, Cheung and Will, 1997 ) . Large hydropower, traditional biomass and geothermic energy are non executable in Hong Kong because of the local conditions and resources. Merely a few undertakings in Hong Kong now have extensively adopted some signifiers of renewable energy, such as solar H2O warming.
However, with turning concerns about energy and the environment, Hong Kong has been working hard in the past decennary to develop energy efficiency programmes and to happen ways to understate the environmental impact of energy production and usage ( ESB, 1998 ) . There is a demand in Hong Kong to set up a renewable energy market so as to fulfill the local demand for green energy and create concern chances for advancing renewable energy in mainland China ( Hui, 1997 ) . Solar energy systems, such as solar thermal and photovoltaics, are believed to be one of the possible countries for future development. Under the Hong Kong ‘s urban context, engineerings that can be integrated into a built environment with high-rise edifices are of import. Countrysides and new towns in Hong Kong are besides possible campaigners for renewable energy systems.
In Hong Kong, use of solar energy for domestic, commercial and industrial intents is affected by the undermentioned factors ( Hong Kong Government, 1985 ) :
High-rise edifices and high population denseness make it hard to happen suited locations for solar aggregators and equipment.
As the demand for heating energy is comparatively low in many edifices, the economic advantage of straight utilizing solar heat is weakened.
The demand of strong anchorage to defy high gales in the typhoon season adds excess costs to the solar energy installing.
In the absence of a local equipment industry, the bulk of the equipment has to be imported from abroad and the monetary value of the equipment is high compared with the possible economy.
Constructing developments in Hong Kong are normally fast path and demand speedy returns on investing. This creates barriers to solar systems which frequently require much clip to plan and hold a longer payback period.
As the energy monetary value in Hong Kong is really low compared with the land and building costs, the developers and edifice proprietors lack the inducement to utilize solar energy systems. With a little figure of applications and limited market, the possible economic sciences of graduated table can non be achieved at present and the consciousness and cognition for the engineering are relatively low.
Despite of the troubles mentioned earlier, the Hong Kong Government has tried to utilize and research solar energy systems in their premises since 1980. The intent is to roll up public presentation informations and construct up experience from the completed installings before the economic advantage of the solar systems can be justified in a concern environment. In recent old ages, a few large-scale undertakings for solar thermic systems have been completed to show the importance of such applications and to alter people ‘s general attitudes.
Solar Thermal System Application
Solar thermic systems utilizing sunshine to heat H2O straight or indirectly have been installed in nine authorities premises with a entire solar aggregation country of over 1,700 M2s. These premises include public bathing machines, prison ( for kitchen and laundry equipment ) , military cantonment, swimming pool composite, infirmary, and a new abattoir. The major maps of hot H2O produced by solar warming are for bathing, pool warming and pre-heating of boiler provender H2O. The estimated payback periods vary from 6 to 27 old ages depending on the use of the systems. Table 3 shows a list of the large-scale solar thermal applications in Hong Kong. Most of them are authorities undertakings installed in rural countries or new towns, since it is hard to happen suited locations in urban countries.
Experience showed that seting solar installing into a new edifice normally is more favorable than retrofitting an bing edifice because the cost of retrofitting in framing and plumbing may be much as the cost of the aggregators for a little undertaking. Sizing the organ pipe and go arounding pump accurately can cut down the operating cost. To avoid waste of thermic energy, insularity should be designed decently. Proper operation and care of the installing are critical to bring forthing of energy and cost nest eggs from the system.
Apart from authorities undertakings, a few private edifices in Hong Kong have tried to put in solar thermic systems for bring forthing hot H2O. Their considerations for economic justification are of import and this is normally met by fiting solar heat with sufficient hot H2O demand, such as in hotels and young person inns.
To better the efficiency of the system, other steps or engineerings may be utilised to congratulate the solar heat, such as the usage of heat pump or heat recovery systems to repossess heat from the air-conditioning works so as to raise H2O temperature in the hot H2O system ( see Figure 1 ) . An incorporate attack to designing of the edifice energy systems is of import for accomplishing an optimum design solution which minimises entire non-renewable energy usage. A careful apprehension of the chilling and warming demands is necessary for planing and fiting the system constituents. This will assist take down the capacity and initial investing of the systems.
Figure 1.AA Solar thermal system integrated with heat pump hair-raiser for hot H2O coevals
The Government ‘s committedness is critical for the development and execution of solar energy systems in Hong Kong since there are assorted institutional and proficient barriers in the free-market concern environment that prevent the renewable energy industry from turning easy by itself. With a vision to accomplish sustainable development in Hong Kong for the twenty-first century, the Government has carried out surveies and considered ways to better urban environment and do better usage of resources ( Planning Department, 1999 ) .
Among the assorted docket points, renewable energy is one of the cardinal issues that most people agreed to prosecute nem con. The major inquiry at this point is to look into the most suited renewable energy for Hong Kong and construct up accomplishments and experience for its development, design and operation. Bear in head the societal and economic conditions of Hong Kong, it is of import to recognize that solutions to the energy jobs are non merely a affair of using engineering and enforcement through statute law. It requires public consciousness and engagement every bit good. Therefore, measures to advance public consciousness and instruction are important for the execution of the renewable energy policy.
Solar energy has definite possibilities in Hong Kong since there is abundant sunshine. High-rise and high-density urban environment create troubles to solar energy applications. Current concern patterns do non favor renewable energy and the Government ‘s function is critical for exciting the market. Although current applications ( solar thermal and photovoltaics ) are little in figure, they can supply valuable information and draw people ‘s attending to the engineering.
Interesting suggestions for utilizing solar systems have been raised in the community. For illustration, it was suggested to construct solar and wind energy systems in the “ Hong Kong Disneyland ” ; a holistic attack for planing solar systems in the new towns was proposed ; main roads and tunnels may be lit and ventilated by a renewable beginning of energy ; solar-powered streetlight systems may be widely adopted. More research and invention are needed to analyze and place suited design options. Partnership between Hong Kong and mainland China will open up a new epoch for accomplishing sustainable energy development.