外文翻譯--酒店冷水機功耗建模和節(jié)能實踐(英文)

1、International Journal of Hospitality Management 33 (2013) 1–5Contents lists available at SciVerse ScienceDirectInternational Journal of Hospitality Managementjournal homepage: www.elsevier.com/locate/ijhosmanPower consum

2、ption modeling and energy saving practices of hotel chillersBarry L. Mak a,?, Wilco W. Chan a, Danny Li b, Leon Liu a, Kevin F. Wong aa School of Hotel Chan and Lam, 2002a,b). Shanghai, asa metropolitan city in China, f

3、aces these environmental problemsas well. The continued economic boom and the growth of tourismactivities in the city bring a significant increase in the number ofhigh-rise hotel buildings and subsequent environmental pr

4、oblems.In fact, the hotels are major energy consumers.The heating ventilation and air-conditioning (HVAC) system insubtropical hotels consumes about 35–50% of electricity, whichranks it as the most energy-consuming facil

5、ity (Chow and Chan,1993). In high latitude countries, like the United Kingdom andGreece, their cooling facilities account for only 4–10% of the totalenergy usage in hotels (Efficiency Office, 1994; Santamouris et al.,199

6、6). In subtropical areas, Yu and Chan (2010) found that the oper-ation of chillers and cooling towers leads to the peak electricitydemand, and accounts for about half of the electricity consumption? Corresponding author

7、at: TH801, School of Hotel and Tourism Management,The Hong Kong Polytechnic University, 17 Science Museum Road, Tsimshatsui East,Hong Kong. Tel.: +852 3400 2269/2346 5633; fax: +852 2362 9362.E-mail address: barry.mak@po

8、lyu.edu.hk (B.L. Mak).for air conditioning in hotels. However, a paucity of informationexists in the relationship among electricity consumption, its asso-ciated parameters, and ways to save the power consumption ofchille

9、rs. The establishment of the relationship between electricityusage and variables of the power consumption of chillers couldenable hoteliers to predict electricity consumption. Predicting theamount of energy consumption m

10、ay help form the benchmark formonitoring the energy usage and efficiency of chillers.Shanghai is the major gateway to mainland China and acts asthe major engine for regional economic developments. The num-ber of internat

11、ional visitors to Shanghai reached 8.5 million in 2010(Shanghai Statistical Bureau, 2011), and this number is expectedto grow in the coming decades. Hence, hotels play a significantrole in the tourism and economic develo

12、pment of Shanghai. In2009, the total number of hotels reached 298, which is twice thenumber in 1990 (China National Tourism Administration, 2010).While Shanghai is not located in the subtropical region, its six toseven m

13、onths of summer hotness require the installation of aircooling facilities in hotels. The foreseeable increase of new hotelswill bring huge energy consumption and its associated emissionproblems. In addition, the initial

14、literature review indicated thatprevious investigations were confined to the study of the overallpower usage and the associated parameters of the HVAC system,and did not look into the core energy consumption of the cooli

15、ngsystem and its related parameters. This gap necessitates conduct-ing the present study. Thus, the present study aims to create amodel of the power consumption of the hotel chillers in Shanghai,and to identify the pract

16、ical means to reduce the power usage ofchillers.0278-4319/$ – see front matter © 2013 Elsevier Ltd. All rights reserved.http://dx.doi.org/10.1016/j.ijhm.2012.12.008B.L. Mak et al. / International Journal of Hospital

17、ity Management 33 (2013) 1–5 3confirms the findings in building energy-related journals, whichindicated that such designs lead to energy savings in chillers. Theresult indicates that the electricity consumption of hotels

18、, whereunequally sized chillers are available, was 283,120 kWh annually.This figure is lower than the electricity consumption of hotels thatused chillers of the same size. Another nearly influential parameteris outdoor t

19、emperature. The number of hotel employees also exertsa statistically significant impact on the electricity consumption ofchillers. Based on the impact of the floor areas on the electricityconsumption of chillers, the GFA

20、 shows a positive relationship withelectricity usage, whereas its magnitude of influence on electricityconsumption appears to be minimal. However, the base figure ofGFA was large and the least floor area was usually over

21、 20,000. Theimpact of this variable on electricity consumption is also deep. Areverse relationship with electricity consumption is exhibited forthe air-conditioned floor area parameter. This result was proba-bly caused b

22、y the stricter control of conserving cooling air in thesefloor areas than the GFA. Nonetheless, its impact on the electricityconsumption of chillers is also minimal.To facilitate the comparison of the total performance o

23、f chillersamong the sampled hotels, the operators in the four-star hotels seg-ment used these models to predict the general electricity demandof chillers in the segment, and then established the yardstick tomonitor the p

24、erformance of their chillers.5. Energy saving operationsThe interviewees mentioned ways to mitigate the power con-sumption of chillers. These recommendations included condensingtemperature control, condenser fan control,

25、 and full-loading modeof chiller operations.Interviewees pointed out that instead of using the conventionalhead pressure to control the compressor power of chillers, energycan be saved by lowering the condensing temperat

26、ure at below-design conditions and the potential saving may up to 20–30%,which is close to the reported savings of Chan and Yu’s (2002) study.This action could result in smaller compression work, reducednumber of operati

27、ng compressors and better chiller efficiency. Thesaving of compressor power from condensing temperature con-trol is always higher than the increase in consumption of the fanpower of the condensers. Furthermore, when all

28、condenser fanswere staged in almost all operating conditions, it reduced the fre-quent on and off cycling of the condenser fan. Subsequent literaturesearch support this point with Yu and Chan (2005) estimated thatcontrol

29、ling the compressor power could save 8–40% energy.In addition, interviewee also highlighted that optimal condenserfan control enhances the airflow and heat transfer area of thecondensers. The application of this control

30、in air-cooled centrifu-gal chillers may also help raising the coefficient of performance(COP). According to Yu and Chan’s (2008) study, it was reported anincrease in COP ranges from 11% to 23% depending on the operatingc

31、onditions.Often, the chiller operates at higher energy efficiency in fullloading and vice versa in part-load conditions. However, in real-ity, every chiller has various properties and field situations, whichcreate differ

32、ences in loading requirements leading to best energyefficiency. In searching for the optimal efficiency for the chiller, theexisting simulation programs are inadequate in many situationsbecause the field may have several

33、 operational parameters thatdiffer from the design. For instance, the computation program onoptimal settings may require evolution strategies with the suitablerecombination operator and arithmetic recombination in situat

34、ionsinvolving chilled water supply and supply of air temperature of theHVAC system during different levels of occupancies and seasons. Byutilizing an evolution strategy, the optimal chiller loading could beworked out wit

35、h high precision within a rapid time frame. Chang(2007), Chang et al. (2009), and Kusiak and Li (2009) shared similarideas to the testing results.In the discussion, interviewees also expressed that there is aneed to cond

36、uct additional independent research on these sug-gested energy saving ideas in the industry so as to collect objectiveproof and measured data to strengthen owners’and managers’con-fidence on the effectiveness of these re

37、commendations. Echoing tothis point, some interviewees suggested that hotel conduct testson the chillers in their properties, and to explore potential energysavings.6. Energy saving designFor design strategies that optim

38、ize the efficiency of chillers, theinterviewees suggested three methods, namely, pre-cooling, load-based speed control, and unequal size of chillers.Pre-cooling air in the system may help chiller reducing itsload and sub

39、sequently energy consumption. Interviewees furtherexplained that since the hotter the air in the system is, the morethe energy is required by the chiller to remove the heat in theair. While interviewees had noted this is

40、 a requirement of thedesign, they hardly provide more details in this aspect in thediscussion.To fill the information gap of pre-cooling design, the authorsconducted a literature search and identified the following. Nogu

41、chiet al. (2007) designed a chemical heat pump that used heliumgas for pre-cooling. This innovation decreased power consump-tion as the chemical heat pump did not require much energy forcooling. They concluded that the n

42、ew helium compression cyclecould save about 7% of power consumption unlike the conven-tional compression system. Yu and Chan (2009) proposed anotherpre-cooling method that used mist, and its calculated economicbenefit. W

43、ith insignificant consumption of water and pump powerassociated with mist generation, this method could account forsavings of 2.9% in the total chiller electricity consumption. Inaddition, the payback period is shorter t

44、han 2 years. Chowdhuryet al. (2009) used building energy simulation software (Ener-gyPlus) to simulate the energy savings of two passive coolingtechniques, namely, pre-cooling and economizer. The simulationsshowed that t

45、he pre-cooling and economizer systems could save115 kW/m2/month and 72 kW/m2/month in total cooling energy,respectively. Savings up to 26 kW/m2/month and 42 kW/m2/monthin chiller energy can be saved by the pre-cooling an

46、d economizersystems, respectively. These three pieces of work further reinforcedthe validity of pre-cooling design may help reducing chillers’energyconsumption.Other than pre-cooling air, several interviewees also sugges

47、tedand supported the use of installing unequal-sized strategy as thereare time slots or chances that a certain chiller may not be required.For instance, the selection for a chiller size meeting the anticipatedcooling dem

48、and of the restaurants or banquet halls which are usu-ally closed after midnight is a usual practice. In addition, installingunequal-sized chillers in a chiller plant could enhance the numberof steps of total cooling cap

49、acity, which could increase the fre-quency of chillers operating at full load. This view is supported byYu and Chan’s (2007) findings that the annual electricity consump-tion of chillers and pumps could save 10.1% if the

50、 chiller plants wereequipped with unequally sized chillers.To improve the energy efficiency of chillers on part load con-ditions, interviewees suggested the integrating several chillersinto one refrigeration cycle. The i