1、 1 English Literature : Evaluating Water Conservation Measures For Green Building In Taiwan Green Building evaluation is a new system in which water conservation is prioritized as one of its seven categories for saving water resources through building equipment design in Taiwan. This paper introduce
2、s the Green Building program and proposes a water conservation index with quantitative methodology and case study. This evaluation index involves standardized scientific quantification and can be used in the pre-design stage to obtain the expected result. The measure of evaluation index is also base
3、d on the essential research in Taiwan and is a practical and applicable approach. Keywords: Green Building； Evaluation system； Water conservation； Building equipment 1. Introduction The environment was an issue of deep global concern throughout the latter half of the 20th century. Fresh water shorta
4、ges and pollution are becoming one of the most critical global problems. Many organizations and conferences concerning water resource policy and issues have reached the consensus that water shortages may cause war in the 21st century,if not a better solution .Actually, Taiwan is already experiencing
5、 significant discord over water supply. Building new dams is no longer an acceptable solution to the current water shortage problems, because of the consequent environmental problems. Previous studies have concluded that water savings are necessary not only for water conservation but also for reduci
6、ng energy consumption. Taiwan is located in the Asian monsoon area and has an abundant supply of rainwater. Annual precipitation averages around 2500mm. However, water shortages have recently been a critical problem during the dry season. The crucial, central issue is the uneven distribution of torr
7、ential rain, steep hillsides, and short rivers. Furthermore, the heavy demand for domestic water use in municipal areas, and the difficulties in building new reservoirs are also critical factors. Government departments are endeavoring to spread publicly the concept of water-conservation. While indus
8、try and commerce have made excellent progress in water conservation, progress among the public has been extremely slow. Due to this global trend, the Architecture and Building Research Institute (ABRI), Ministry of Interior in Taiwan, proposed the Green Building concept and built the evaluation syst
9、em. In order to save water resources through building equipment design, this system prioritizes water conservation as one of its seven categories. This paper focuses on the water conservation measures for Green Building in Taiwan and a quantitative procedure for proving water-saving efficiency. The
10、purpose of this work is not only aimed at saving water resources, but also at reducing the environmental impact on the earth. 2. Water conservation index The water conservation index is the ratio of the actual quantity of water consumed in a building to the average water-consumption in general. The
11、index is also called, the water saving rate. Evaluations of the water-consumption quantity include the evaluation to the water-saving efficiency within kitchens, bathrooms and all water taps, as well as the recycling of rain and the secondhand intermediate water. 2 2.1. Goal of using the water conse
12、rvation index Although Taiwan has plenty of rain, due to its large population, the average rainfall for distribution to each individual is poor compared to the world average as shown in Fig. 1.Thus, Taiwan is reversely a country short of water. Yet, the recent improvements in citizens standards of l
13、iving have led to a big increase in the amount of water needed in cities, as shown in Fig. 2, which, accompanied by the difficulty of obtaining new water resources, makes the water shortage problem even worse. Due to the improper water facilities designs in the past, the low water fee, and the usual
14、 practical behavior of people when using water, Taiwanese people have tended to use a large quantity of tap water. In 1990,the average water-consumption quantity in Taiwan was 350l per person per day, whereas in Germany it is about 145l per person per day, and in Singapore about 150l per person per
15、day. These statistics reveal the need for Taiwanese people to save water. The promotion of better-designed facilities which facilitate water-saving will become a new trend among the public and designers, because of concerns for environmental protection. The water conservation index was also designed
16、 to encourage utilization of the rain, recycling of water used in everyday life and use of water-saving equipment to reduce the expenditure of water and thus save water resources. 2.2. Methodology for efficient use of water resources Some construction considerations and building system designs for e
17、ffective use of water resources are described below. 2.2.1. Use water-conservation equipment A research of household tap-water consumption revealed that the proportion of the water used in flushing toilets and in bathing, amounts to approximately 50% of the total household water consumption, as give
18、n in Table 1. Many construction designers have tended to use luxurious water facilities in housing, and much water has thus been wasted. The use of water-saving equipment to replace such facilities is certain to save a large amount of water. For example, the amounts of water used in taking a shower
19、and having a bath is quite different. A single shower uses around 70l of water, whereas a bath uses around 150l. Furthermore, current construction designs for housing in Taiwan tend to put two sets of bathtubs and toilets, and quite a few families have their own massage bathtubs. Such a situation ca
20、n be improved only by removing the tubs and replacing them with shower nozzles, so that more water can be possibly saved. The commonly used water-saving devices in Taiwan now include new-style water taps, water-saving toilets, two-sectioned water closets, water-saving shower nozzles, and auto-sensor
21、 flushing device systems, etc. Water-saving devices can be used not only for housing, but also in other kinds of buildings. Public buildings, in particular, should take the lead in using water-saving devices. 2.2.2. Set up a rain-storage water supply device The rain-storage water supply device store
22、s rain using natural landforms or man-made devices, and then uses simple water-cleaning procedures to make it available for use in houses. Rain can be used not only as a substitute water supply, but also for re control. Its use also helps to decrease the peak-time water load in cities. The annual av
23、erage rainfall in Taiwan is about 2500 mm, almost triple better than the global average. However, due to geographic limitations, we could not build enough water storage devices, such as dams, to save all the rain. It is quite a pity that annually about 80% of the rain in Taiwan is wasted and flows d
24、irectly into the sea, without being saved and stored. The rain-storage water supply system is used with a water-gathering system, water-disposal system, water-storage system and water-supply system. First, the 3 water-gathering system gathers the rain. Then, the water flows to the water-disposal sys
25、tem through pipes, before being sent to the water-storage system. Finally, it is sent to the usersequipment through another set of pipes. Using the drain on the roof of a building, leading to the underground water-storage trough, is considered an effective means of gathering rain. The water, after s
26、imple water-disposal processes, can be used for chores such as house cleaning, washing floors, air-conditioning or watering plants. 2.2.3. Establishing the intermediate water system Intermediate water is that gathered from the rain in cities, and includes the recycled waste-water which has already b
27、een disposed of and can be used repeatedly only within a certain range, but not for drinking or human contact. Flushing the toilet consumes 35% of all water. If everyone were to use intermediate water to flush toilets, much water could be efficiently saved. Large-scale intermediate water system devi
28、ces are suggested to be built up regularly with in a big area. Each intermediate water system device can gather, dispose and recycle a certain quantity of waste-water from nearby government buildings, schools, residences, hotels, and other buildings. The obtained water can be used for flushing toile
29、ts, washing cars, watering plants and cleaning the street, or for garden use and to supplement the water of rivers or lakes. A small-scale intermediate water system gathers waste-water from everyday use, and then, through appropriate water-disposal procedures, improves the water quality to a certain
30、 level, so that finally it can be repeatedly used for non-drinking water. There are extensive ways to use the intermediate water. It can be used for sanitary purposes, public fountains, watering devices in gardens and washing streets. In order to recycle highly polluted waste-water, a higher cost is
31、 needed for setting up the associated water-disposal devices, which are more expensive and have less economic benefits than the rain-utilization system. Except for the intermediate water-system set within a single building, if we build them within large-scale communities or major construction develo
32、pment programs, then it is sure to save more water resources efficiently and positively for the whole country as well as improve the environmental situation. 3. Water conservation index and basis Present research into the utilization of water resources mainly considers residential buildings, while d
33、ata for other kinds of buildings are comparatively few. Since daily water consumption of the citizen is mainly from their private dwellings, the indicator of utilizing water resources thus focuses on the actual water-saving quantity as far as residential buildings are concerned. Research that relate
34、s to other kinds of buildings focuses on the adoption rate of simply equipped water-saving equipment. Table 1 shows the average and maximum daily household water consumption of each Taiwanese person, from which a standardized daily total water-consumption of 2501 per person per day is estimated and
35、set as the calculation base. 3.1. Calculation The actual water-saving rate(WR) is calculated according to Formula (1). Formula (3) shows that a qualified value of WR should be 0:8. A building with a qualified WR is eligible to apply for the Green Building incentive payment. According to Formula(2),t
36、he adoption rate of water-saving equipment (AR) can be used to estimate the water-saving conditions in other kinds of buildings, and the guideline is shown in Formula (4). A qualified value of AR should be higher than 0.8. Except the residential type of building, a building with a qualified AR is eligible to apply for the Green Building incentive payments. The Formula of calculating the water resource index for the residential buildings (The Actual Water-saving Rate； WR) is as follows:
