Research Papers

On the Climate Variability and Energy Demands for Indoor Human Comfort Levels in a Tropical-Coastal Urban Environment

[+] Author and Article Information
Rabindra Pokhrel

CUNY City College of New York,
New York, NY 10031
e-mail: r5pokhrel@gmail.com

Luis Enrique Ortiz

CUNY City College of New York,
New York, NY 10031
e-mail: luis.ortiz.uriarte@gmail.com

Nazario D. Ramírez-Beltran

Department of Industrial Engineering,
University of Puerto Rico-Mayagüez,
Mayaguez 00680, Puerto Rico
e-mail: nazario.ramirez@upr.edu

Jorge E. González

Fellow ASME
NOAA-CREST Professor of
Mechanical Engineering,
The City College of New York,
NY 10031
e-mail: jgonzalezcruz@ccny.cuny.edu

1Corresponding author.

Contributed by the Solar Energy Division of ASME for publication in the JOURNAL OF SOLAR ENERGY ENGINEERING: INCLUDING WIND ENERGY AND BUILDING ENERGY CONSERVATION. Manuscript received January 31, 2018; final manuscript received August 1, 2018; published online October 1, 2018. Assoc. Editor: Ming Qu.

J. Sol. Energy Eng 141(3), 031002 (Oct 01, 2018) (9 pages) Paper No: SOL-18-1047; doi: 10.1115/1.4041401 History: Received January 31, 2018; Revised August 01, 2018

The main objective of this study is to identify how climate variability and urbanization influence human comfort levels in tropical-coastal urban environments. San Juan Metro Metropolitan Area (SJMA) of the island of Puerto Rico was chosen as a reference point. A new human discomfort index (HDI) based on environmental enthalpy is defined to determine the energy required to maintain indoor human comfort levels. Regression analysis shows that both temperature and HDI are good indictors to predict total electrical energy consumption. Results showed that over the past 35 years, the average environmental enthalpy have increased, resulting in the increase of average HDI with clear bias due to urbanization. Local scale weather station data show a decreasing rate of maximum cooling per capita at –11.41 kW h/years and increasing of minimum cooling per capita of 10.64 kW h/years; however, for the whole Caribbean region, an increasing trend is observed for both minimum and maximum cooling per capita. To estimate human comfort levels under extreme heat wave events conditions, an event of 2014 was identified. The analysis is complemented by simulations from the weather forecasting system (WRF) at a resolution of 1 km, forced by data from the National Center for Environmental Prediction at 250 km spatial resolution. WRF model results were evaluated against observations showing good agreement for both temperature and relative humidity (RH) and improvements. It also shows that energy per capita in urban areas during a heat wave event can increase to 21% as compared to normal day.

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Intergovernmental Panel on Climate Change, 2007, “ Climate Change 2007: The Physical Science Basis,” Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Cambridge University Press, Cambridge, UK.
Glenn, E. , Comarazamy, D. , González, J. E. , and Smith, T. , 2015, “ Detection of Recent Regional Sea Surface Temperature Warming in the Caribbean and Surrounding Region,” Geophys. Res. Lett., 42(16), pp. 6785–6792. [CrossRef]
González, J. E. , Georgescu, M. , Lemos, M. C. , Hosannah, N. , and Niyogi, D. , 2017, “ Climate Change's Pulse is in Central America and the Caribbean,” Eos, 98, (epub).
González-Cruz, J. E. , Pedro, S. , Yanellys, M. , José, P. , Amanuel, T. G. , and Robert, B. , 2013, “ Climate Vulnerability: Understanding and Addressing Threats to Essential Resources,” Vulnerability of Energy to Climate, R. A. Pielke, ed., Elsevier, Amsterdam, The Netherlands.
Ramirez-Beltran, D. N. , Gonzalez, J. E. , Castro, J. M. , Angeles, M. , Harmsen, E. W. , and Salazar, C. M. , 2017, “ Analysis of the Heat Index in the Mesoamerica and Caribbean Region,” Am. Meteorol. Soc. 56(11), pp. 2905–2925.
Méndez-Lázaro, P. , Martínez-Sánchez, O. , Méndez-Tejeda, R. , Rodríguez, E. , Morales, E. , and Schmit Cortijo, N. , 2015, “ Extreme Heat Events in San Juan Puerto Rico: Trends and Variability of Unusual Hot Weather and Its Possible Effects on Ecology and Society,” J. Climatol. Weather Forecasting, 3(135), epub.
Comarazamy, D. , González, J. E. , Luvall, J. , Rickman, D. , and Bornstein, R. , 2013, “ Climate Impacts of Land-Cover and Land-Use Changes in Tropical Islands Under Conditions of Global Climate Change,” J. Clim., 26, pp. 1535–1550.
Velazquez-Lozada, A. , Gonzalez, J. E. , and Winter, A. , 2007, “ Urban Heat Island Studies for San Juan, Puerto Rico,” J. Atmos. Environ., 40(9), pp. 1731–1741. [CrossRef]
Poupkou, A. , Nastos, P. , Melas, D. , and Zerefos, C. , 2011, “ Climatology of Discomfort Index and Air Quality Index in a Large Urban Mediterranean Agglomeration,” Water Air Soil Pollut., 222(1–4), pp. 163–183. [CrossRef]
Lai, L.-W. , and Wan-Li, C. , 2010, “ Urban Heat Island and Air Pollution-An Emerging Role for Hospital Respiratory Admissions in an Urban Area,” J. Environmental Health, 72(6), pp. 32–35.
McGregor, G. R. , Markou, M. , Bartzokas, T. A. , and Katsoulis, B. D. , 2002, “ An Evaluation of the Nature and Timing of Summer Human Thermal Discomfort in Athens, Greece,” Clim. Res., 20, pp. 83–94. [CrossRef]
Pantavou, K. , Theoharatos, G. , Nikolopoulos, G. , Katavoutas, G. , and Asimakopoulos, D. , 2008, “ Evaluation of Thermal Discomfortin Athens Territory and Its Effect on the Daily Number of Recorded Patients at Hospitals' Emergency Rooms,” Int. J. Biometeor., 52(8), pp. 773–778. [CrossRef]
Lemonsu, A. V. , Viguié, M. , Daniel, V. , and Masson , 2015, “ Vulnerability to Heat Waves: Impact of Urban Expansion Scenarios on Urban Heat Island and Heat Stress in Paris (France),” Urban Clim., 14, pp. 586–605. [CrossRef]
Epstein, Y. , and Moran, D. S. , 2006, “ Thermal Comfort and the Heat Stress Indices,” Ind. Health, 44(3), pp. 388–398. [CrossRef] [PubMed]
Anderson, G. B. , Bell, M. L. , and Peng, R. D. , 2013, “ Methods to Calculate the Heat Index as an Exposure Metric in Environmental Health Research,” Environ Health Perspect., 121, pp. 1111–1119. [CrossRef] [PubMed]
Akbari, H. , David, S. , Dorsano, S. , Huang, J. , and Winett, S. , 1992, “ Cooling Our Commutities—A Guidebook on Tree Planting and Light Colored Surfacing,” Climate Change Division, U.S. Environmetal Protection Agency, Office of Policy Analysis, Washington, DC.
Gutiérrez, E. , González, J. E. , Bornstein, R. , and Arend, M. , 2013, “ A New Modeling Approach to Forecast Building Energy Demands During Extreme Heat Events in Complex Cities,” ASME J. Sol. Energy Eng., 135(4), p. 040906. [CrossRef]
Krarti, A. , Ortiz, L. , and González, J. E. , 2017, “ On the Spatio-Temporal End-User Energy Demands of a Dense Urban Environment,” ASME J. Sol. Energy Eng., 139(4), p. 010051.
U.S. Bank Trust National Association Trustee, 2013, “ Fortieth Annual Report on the Electric Property of the Puerto Rico Electric Power Authority, San Juan, Puerto Rico,” U.S. Bank Trust National Association Trustee, San Juan, PR, accessed Dec. 1, 2017, http://energia.pr.gov/wp-content/uploads/2015/09/Consulting-Engrs-Annual-Report-FY2013-21.pdf
U.S. DOE, 2012, “ 2011 Buildings Energy Data Book. Energy Efficiency Renewable Energy,” U.S. Department of Energy, Washington, DC, accessed Mar. 12, 2017, https://openei.org/doe-opendata/dataset/6aaf0248-bc4e-4a33-9735-2babe4aef2a5/resource/3edf59d2-32be-458b-bd4c-796b3e14bc65/download/2011bedb.pdf
Urge-Vorsatz, D. , Cabeza, L. F. , Serrano, S. , Barreneche, C. , and Petrichenko, K. , 2015, “ Heating and Cooling Energy Trends and Drivers in Buildings,” J. Renewable Sustainable Energy, 41, pp. 85–98. [CrossRef]
Crawley, D. , 2008, “ Estimating the Impacts of Climate Change or Urbanization on Building Performance,” J. Build. Perform. Simul., 1(2), pp. 91–115. [CrossRef]
Lu, N. , Leung, L. , Wong, P. , Paget, M. , Taylor, Z. , Correia, J. , Mackey, P. , Jiang, W. , and Xie, Y. , 2008, “ Climate Change Impacts on Residential and Commercial Loads in the Western U.S. Grid,” IEEE Trans. Power Syst., 25(1), pp. 480–488.
Liddament, M. W. , and Orme, M. , 1998, “ Energy and Ventilation,” Appl. Therm. Eng., 18(11), pp. 1101–1109. [CrossRef]
Angeles, E. M. , Gonzalez, J. E. , and Ramirez, N. , 2017, “ Impacts of Climate Change on Building Energy Demands in the Intra-Americas Region,” Theor. Appl. Climatol., 133, pp. 59–72.
ANSI/ASHRAE, 2003, “ Ventilation for Acceptable Indoor Air Quality, ANSI/ASHRAE Addendum n to ANSI/ASHRAE,” ANSI/ASHRAE, Atlanta, GA, Standard No. ANSI/ASHRAE 62-2001. https://www.ashrae.org/File%20Library/Technical%20Resources/Standards%20and%20Guidelines/Standards%20Addenda/62-2001/62-2001_Addendum-n.pdf
Karl, T. R. , and Knight, R. W. , 1997, “ The 1995 Chicago Heat Wave: How Likely Is a Recurrence?,” Bull. Amer. Meteor. Soc., 78(6), pp. 1107–1119. [CrossRef]
Delworth, T. L. , Mahlman, J. D. , and Knutson, T. R. , 1999, “ Changes in Heat Index Associated With CO2-Induced Global Warming,” Climatic Change, 43, pp. 369–386. [CrossRef]
Robinson, P. , 2001, “ On the Definition of a Heat Wave,” J. Appl. Meteor., 40(4), pp. 762–775. [CrossRef]
Fischer, E. M. , and Schär, S. , 2010, “ Consistent Geographical Patterns of Changes in High-Impact European Heatwaves,” Nat. Geosci., 3(6), pp. 398–403. [CrossRef]
Deo, R. C. , McAlpine, C. A. , Syktus, J. , McGowan, H. A. , and Phinn, S. , 2007, “ On Australian Heat Waves: Time Series Analysis of Extreme Temperature Events in Australia,” International Congress on Modelling and Simulation, L. Oxley and D. Kwasiri , eds., Modelling and Simulation Society of Australia and New Zealand, pp. 626–635.
Perkins, S. E. , and Alexander, L. V. , 2012, “ On the Measurements of Heat Waves,” J. Clim., 26, pp. 4500–4516. [CrossRef]
Colombo, A. , Etkin, D. , and Karney, B. , 1999, “ Climate Variability and the Frequency of Extreme Temperature Events for Nine Sites Across Canada: Implications for Power Usage,” J. Clim., 12(8), pp. 2490–2502. [CrossRef]
Skamarock, W. C. , Klemp, J. B. , Dudhia, J. , Gill, D. O. , Barker, D. M. , Duda, M. G. , Huang, X.-Y. , Wang, W. , and Powers, J. G. , 2008, “ A Description of the Advanced Research WRF Version 3,” National Center for Atmospheric Research, Boulder, CO, Report No. NCAR/TN-4751STR. http://opensky.ucar.edu/islandora/object/technotes:500
Mlawer, E. J. , Taubman, S. J. , Brown, P. D. , Iacono, M. J. , and Clough, S. A. , 1997, “ Radiative Transfer for Inhomogeneous Atmospheres: RRTM, a Validated Correlated-k Model for the Longwave,” J. Geophys. Res., 102(D14), pp. 16663–16682. [CrossRef]
Dudhia, J. , 1989, “ Numerical Study of Convection Observed During the Winter Monsoon Experiment Using a Mesoscale Two-Dimensional Model,” J. Atmos. Sci., 46(20), pp. 3077–3107. [CrossRef]
Jimenez, P. A. , and Dudhia, J. , 2012, “ Improving the Representation of Resolved and Unresolved Topographic Effects on Surface Wind in the WRF Model,” J. Appl. Meteorol. Climatol., 51(2), pp. 300–316. [CrossRef]
Kain, J. S. , 2004, “ The Kain–Fritsch Convective Parameterization: An Update,” J. Appl. Meteorol., 43(1), pp. 170–181. [CrossRef]
Hong, S.-Y. , and Lim, J.-O. J. , 2006, “ The WRF Single-Moment 6-Class Microphysics Scheme (WSM6),” J. Korean Meteor. Soc., 42(2), pp. 129–151. http://www2.mmm.ucar.edu/wrf/users/phys_refs/MICRO_PHYS/WSM6.pdf
Comarazamy, D. , González, J. E. , Luvall, J. , Rickman, D. , and Mulero, P. J. , 2010, “ A Land-Atmospheric Interaction Study in the Coastal Tropical City of San Juan, Puerto Rico,” Earth Interact. J., 14(16), pp. 1–24. [CrossRef]
Reddy, Agami , Kreider, Jan F. , Curtiss, Peter. , and Rabl , 2016, Ari, Heating and Cooling of Buildings: Design for Efficiency, 3rd ed., CRC Press, Boca Raton, FL.
Lebassi, B. , González, J. E. , Fabris, D. , Milesi, C. , Miller, N. L. , Switzer, P. , and Bornstein, R. , 2009, “ Observed 1970-2005 Cooling of Summer Daytime Temperatures in Coastal California,” J. Clim., 22(13), pp. 3558–3573. [CrossRef]


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Fig. 1

Weather forecasting system domain configuration

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Fig. 2

Land cover land use and topography over SJMA

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Fig. 3

Monthly records of total electrical energy consumption and population in millions kW h during a period of 1980–2016

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Fig. 4

Climatology of EPC in kW h/person/month from utility records

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Fig. 5

Climatology of HDI for San Juan International Airport (SJIA)

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Fig. 6

Time series for yearly maximum, minimum, and mean cooling for SJIA. Time series for yearly maximum, minimum, and mean cooling for whole Caribbean region.

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Fig. 7

Time series for yearly maximum, minimum, and mean cooling for whole Caribbean region

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Fig. 8

Scatter plot for HDI and EPC per month (a), minimum temperature and HDI (b), and maximum temperature and HDI (c) for a period of 1980–2014

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Fig. 9

Climatology of heat wave event frequency (SJIA) with total energy consumption (utility)

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Fig. 10

Temperature variation from Sept. 9, 2014 to Oct. 2, 2014 for NCEP, NARR, stations, and WRF output (run1)

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Fig. 11

Relative humidity variation from Sept. 29, 2014 to Oct. 2, 2014 for NCEP, NARR, stations, and WRF output

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Fig. 12

Variation of EPC per day during fourth day (left), third day (middle), and during normal day (right). Green contour levels of 13 represent urban areas; contour lines of topography are also plotted at an interval of 200.

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Fig. 13

Temperature profile for run1 (city) and run2 (no city) case

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Fig. 14

Urban heat island and increase in HDI



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