Cool Roofs Benefits: Introduction

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Heat island which is the most documented phenomenon of climatic change is related to the increase of urban temperatures compared to the suburban. Among the various urban heat island mitigation techniques, cool roofs are the most promising since they simultaneously contribute to buildings’ energy efficiency.
The temperature of cities continues to increase because of the heat island phenomenon and the undeniable climatic change. The observed high ambient temperatures intensify the energy problem of cities, deteriorates comfort conditions, put in danger the vulnerable population and amplify the pollution problems.
Cool roofs can reduce cooling-energy use in air conditioned buildings and increase comfort in unconditioned buildings.
Cool roofs and cool pavements mitigate summer urban heat islands, improving outdoor air quality and comfort.
Installing cool roofs and cool pavements in cities worldwide is a compelling win–win activity that can be undertaken immediately, outside of international negotiations to cap CO2 emissions.
The EU – GCC Clean Energy Network aims to respond to the common interests of stakeholders, both in the GCC and the EU, active in the field of clean energy. The EU - GCC Clean Energy Network is the practical instrument for development of concrete cooperation activities on clean energy, including the related policy and technology aspects, among various players across the EU and GCC countries. http://www.eugcc-cleanergy.net/
The ECRC is a European non- profit organization that maintains an independent product rating program to measure the radiative properties of the surface layer of roofing products. Government entities or other interested parties may refer to the ECRC as a reliable, credible source of radiative property data. http://coolroofcouncil.eu/
The Abolin Co is a cool roofs and pavements manufacturer. www.abolinco.com

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Cool Roofs Benefits: Introduction

  1. 1. COOL ROOFS AND PAVEMENTS SAVE ENERGY COOL THE CITIES FIGHT GLOBAL WARMING Prokopis Perdikis U.G.I CYPRUS/ABOLIN CO GREECE Marketing Committee Leader European Cool Roofs Council 3rd Discussion Groups’ Meeting 24-25 November, 2011,Athens, Greece U.G.I CYPRUS
  2. 2. The problem:  Cities not only generate the increasing need for energy consumption for cooling but at the same time are becoming more and more a serious source of pollutants that contribute in GlobalWarming.  Buildings are responsible for 40% of energy consumption and 36% of EU CO2 emissions.  Buildings in the United States are responsible for 39% of CO2 emissions, 40% of energy consumption, 13% water consumption per year.  The UAE is currently the worlds’ largest user of energy on a per capita basis, with 70 per cent of primary domestic energy usage being committed to buildings. All GCC countries fall in the top 25 countries of carbon dioxide emissions per capita, with UAE leading  Urbanization increase the demand for cooling energy and accelerate the formation of smog. 3rd Discussion Groups’ Meeting 24-25 November, 2011,Athens, Greece
  3. 3. Related Problems:  ENERGY CONSUMPTION  URBAN HEAT ISLAND  AIR POLLUTION  GLOBALWARMING 3rd Discussion Groups’ Meeting 24-25 November, 2011,Athens, Greece
  4. 4.  Every year, nearly half (49%) of all energy produced in the U.S. is consumed by the Building Sector, in Europe almost the 40% , in UAE almost the 70% Energy Consumption: Buildings 3rd Discussion Groups’ Meeting 24-25 November, 2011,Athens, Greece http://www.iea.org/weo/database_electricity/WEO2005-Chapter%206.pdf
  5. 5. Co2 Emissions: Buildings Institute of Physics in Berlin- Adlershof 3rd Discussion Groups’ Meeting 24-25 November, 2011,Athens, Greece The statistics of the UAE show that the increase in CO2 emissions ( Not only buildings) is within the range of 33% and 35% between 1997 and 2006 http://www.eia.doe.gov/cabs/UAE/Electricity.html
  6. 6. URBAN HEAT ISLAND: 1  City centers in comparison to suburban areas demonstrate higher level of temperatures, which in some cases can be even 10 oC higher. When a city is built, changes are made to the natural environment that affect the temperature.The changes affect energy transfers and the storage of energy. 3rd Discussion Groups’ Meeting 24-25 November, 2011,Athens, Greece Source:http://heatisland.lbl.gov/
  7. 7. URBAN HEAT ISLAND: 2  One of the factors that play decisive role in the growth of phenomenon of urban heat island they are the thermal attributes of MATERIALS that are used in the urban environment:  Construction materials generally have a lower albedo than soil and vegetation. The result is that buildings, streets, parking lots, etc. absorb more solar radiation than soil and vegetation. The increased absorption of solar radiation makes the city warmer than the surrounding rural area on sunny days.  Construction materials generally have higher heat capacities than soil and vegetation.This means that buildings, streets and parking lots tend to retain internal energy longer and stay warmer than surrounding rural areas especially at night. 3rd Discussion Groups’ Meeting 24-25 November, 2011,Athens, Greece
  8. 8. U.H.I : MATERIALS - Albedo 3rd Discussion Groups’ Meeting 24-25 November, 2011,Athens, Greece
  9. 9. U.H.I : MATERIALS - Storage of Energy 3rd Discussion Groups’ Meeting 24-25 November, 2011,Athens, Greece
  10. 10. Related problems: Increased needs for cooling Increased need for energy Decreased thermal comfort Increased smog production: Because of smog is a photochemical phenomenon, it is also related to temperature. Extensive scientific reports demonstrate that per 1 oC rise of temperature a 5% Smog increase is taking place. 3rd Discussion Groups’ Meeting 24-25 November, 2011,Athens, Greece
  11. 11. Proposed solution: 3rd Discussion Groups’ Meeting 24-25 November, 2011,Athens, Greece Source:http://heatisland.lbl.gov/
  12. 12. Source:http://heatisland.lbl.gov/ 3rd Discussion Groups’ Meeting 24-25 November, 2011,Athens, Greece incident sunlight I reflected sunlight Rsol × I net emitted thermal radiation E × σ (T4 - Tsky 4) opaque surface at temperature T convection conduction • High solar reflectance (Rsol) lowers solar heat gain (0.3 - 2.5 µm) • High thermal emittance (E) enhances thermal radiative cooling (4 - 80 µm) Proposed solution: high solar reflectance + high thermal emittance = low surface temperature
  13. 13. Proposed solution: The creation of surfaces of high reflectivity and emissivity in the urban environment constitutes an easily applicable and economic passive cooling method that contributes in the reduction of urban temperatures.The creation of such surfaces can be achieved with the use of “cool” materials which are characterized from : - High solar reflectance - High infrared emittance 3rd Discussion Groups’ Meeting 24-25 November, 2011,Athens, Greece
  14. 14. Cool Materials vs Standard 3rd Discussion Groups’ Meeting 24-25 November, 2011,Athens, Greece
  15. 15.  Cooling load reduction - Less heat penetrates into building  Energy Savings - Minimize the need for cooling  Money savings  Improved thermal comfort conditions  Improved public health conditions  Enhanced building’s durability - Less thermal stress  Improved microclimatic conditions - Urban Heat Island Mitigation Cool Materials: Consequences in Building level 3rd Discussion Groups’ Meeting 24-25 November, 2011,Athens, Greece
  16. 16. Cool Materials: Consequences in Building level The calculated cooling loads for the base case (roof SR equal to 0.2) and the two increased albedo Cool Barrier Coatings cases and the corresponding % decrease in cooling loads between the base case and the two scenarios. In all case studies the U-value of the roof was set to be equal to 0.84 W/m2 K. For the Calculation TRNSYS SOFTWARE WAS USED. It should be pointed out that the values mentioned in this part depend on the prototype buildings characteristics and therefore are only indicative. Place Cooling load (kWh/m2) Decrease in cooling load between base case and case:1 Decrease in cooling load between base case and case:2 Base case (SR = 0.2) Cool Barrier case: 1 (SR = 0.6) Cool Barrier case: 2 (SR = 0.85) Athens 58.0 43.3 34.6 25% 40% Baghdad 144.3 125.8 114.1 13% 21% Riyadh 179.1 154.8 139.5 14% 22% Damascus 61.0 46.8 38.4 23% 37% Ankara 35.4 24.2 17.9 32% 49% Teheran 80.2 65.5 56.3 18% 30% Alexandria 75.1 57.2 46.6 24% 38% Cairo 104.5 84.6 72.4 19% 31% Abolin Co. Greece 3rd Discussion Groups’ Meeting 24-25 November, 2011,Athens, Greece www.abolinco.com
  17. 17. Cool Materials: Consequences in Building level Table : Cooling degree days (base 18°C) and potential cooling energy savings (kWh per 100m2 of roof area). Roofing insulation of 1.94 m2K/W (R-11 insulation). The estimates of savings are for an increase in roof solar reflectance from a typical dark roof of 0.1 to a cool-colored roof of 0.4. Country City CDD18 Savings Country City CDD18 Savings Algeria Argentina Australia Bermuda Brunei China Cyprus Egypt Greece India Indonesia Jamaica Jordan Kenya Libya Malaysia Alger/Dar-El-Beida BuenosAires/Ezeiza Sydney/K Smith St Georges/Kindley BruneiAirport Beijing (Peking) Akrotiri Cairo Athenai/Hellenikon Bombay/Santa Cruz Calcutta/Dum Dum Djakarta/Halimperd Amman Nairobi Airport Tripoli/Idris Kuala Lumpur 899 678 2,511 1,802 3,516 840 1,139 1,833 1,030 3,386 3,211 3,390 1,063 566 1,686 3,475 366 301 841 632 1137 349 437 641 405 1099 1047 1100 414 268 598 1125 Morocco Mozambique Pakistan Philippines Saudi Arabia Senegal Singapore Syria Taiwan Tanzania Thailand Tunisia Turkey Zimbabwe Rabat-Sale Maputo Karachi Airport ManilaAirport Dhahran Medina Riyadh Dakar/Yoff Singapore/Changi DamascusAirport Taipei Dar es Salaam Bangkok Tunis/ElAouina Istanbul/Yesilkoy Harare Airport 606 2,085 3,136 3,438 3,340 3,691 3,304 2,445 3,647 1,074 2,204 2,922 3,962 1,102 567 775 280 715 1025 1114 1085 1189 1075 822 1176 417 750 962 1269 426 268 329 www.globalcoolcities.org/ 3rd Discussion Groups’ Meeting 24-25 November, 2011,Athens, Greece
  18. 18.  Urban Heat Island mitigation –Temperature and Smog reduction  Lower surface temperature increase thermal comfort conditions of the land users.  Lower air temperatures penetrate into the surrounding buildings – thermal comfort in buildings –energy savings Cool Materials: Consequences in City level 3rd Discussion Groups’ Meeting 24-25 November, 2011,Athens, Greece Downtown Dallas Surface Temperatures
  19. 19. EFFECT OF COOL MATERIAL USE INTHE REDUCTION OFTHE GLOBALTEMPERATURE AND IN THE REDUCTION OF GREENHOUSES GASES EMITTANCE Cool Materials: Global Warming 3rd Discussion Groups’ Meeting 24-25 November, 2011,Athens, Greece
  20. 20. The increase in greenhouse gases emissions and in particular CO2, resulting from anthropogenic activities, contributes to the planet average temperature rise. In the last 50 years, the increase of greenhouse gases concentration in the atmosphere has produced an average global temperature rise of about 0,6 ± 0,2°C According to the fourth report presented on Feb. 2007 in Paris, global temperature increase is expected to rise from 1.8 to 4 degrees up to the end of 2100. (IPCC) Intergovernmental Panel on Climate Change Cool Materials: Global Warming 3rd Discussion Groups’ Meeting 24-25 November, 2011,Athens, Greece
  21. 21. As the Earth gets warmer, it becomes a source of heat through electromagnetic radiation radiated towards the Universe. Such long wavelength radiation (earth heat) gets through the atmosphere to be dissipated in the outer space with greater difficulty. CO2 and other climate-affecting gases (greenhouse effect) increase such phenomenon. Solar energy is irradiated on the Earth by electromagnetic radiation with a short wavelength:  26% of it is reflected by clouds and particles in the atmosphere  19% of it is absorbed by clouds, gases and particles in the atmosphere;  Remaining part of it (55%) arrives to the surface where is mainly absorbed by the ground and the ocean, warming the planet. Cool Materials: Global Warming Earth energy flows 3rd Discussion Groups’ Meeting 24-25 November, 2011,Athens, Greece
  22. 22. For the reduction of the climate - affecting greenhouse gases emissions, international community, European Union, and single countries have searched solutions through agreements, directives and rules (Kyoto Protocol, renewable energy and energy saving directives and incentives). Another solution is to enhance the average Earth’s albedo increasing the solar energy which is reflected by the Earth. Such energy doesn’t add to the Earth’s warming. Cool Materials: Global Warming 3rd Discussion Groups’ Meeting 24-25 November, 2011,Athens, Greece
  23. 23.  Proposed technology is to immediately reflect, as soon as it reaches the earth surface, a portion of the solar short wavelength radiation before it becomes long wavelength heat  From in-depth scientific researches (CIRIAF National Congress March 2007 Ph Rossi et al) , pinpoint that a certified white reflecting surface of about 1 m2 with a reflection coefficient higher than 90-95%, can compensate in one year (depending on latitude and orientation of surfaces) the production 50-100 kg of equivalent carbon dioxide www.albedocontrol.it/Pubblicazioni/ALBEDOSAT Cool Materials: Global Warming 3rd Discussion Groups’ Meeting 24-25 November, 2011,Athens, Greece
  24. 24. Using cool roofs and cool pavements in urban areas, on the average, can increase the albedo of the urban areas by 0.1. We estimate that increasing the albedo of urban roofs and paved surfaces will induce a negative radiative forcing on the earth surface equivalent to removing 22 Gt CO2 from atmosphere. Given these potential savings, we would like to recommend establishing an international organization where the developed countries offer financial support to large cities in developing countries, to trigger a cool roof/pavement program in those cities. Hashem Akbari and Surabi Menon Lawrence Berkeley National Laboratory, USA H_Akbari@LBL.gov Arthur Rosenfeld California Energy Commission, USA ARosenfe@energy.state.ca.us 2006 Cool Materials: Global Warming 3rd Discussion Groups’ Meeting 24-25 November, 2011,Athens, Greece
  25. 25. Cool Materials: Global Warming/Kyoto Goals 3rd Discussion Groups’ Meeting 24-25 November, 2011,Athens, Greece Country CO2 emission in 1990 Mt Kyoto’s reduction commitment (%) Requested Cool Roof White to fulfill Kyoto’s goal (km2) Cool Roof White necessary to compensate all CO2 emission (km2) Austria 59,20 8 113,66 1.420,80 Belgium 113,40 8 217,74 2.721,72 Bulgaria 82,99 8 159,34 1.991,76 Denmark 52,10 8 100,03 1.250,40 Estonia 37,79 8 72,57 907,13 Finland 53,90 8 103,49 1.293,60 France 366,53 8 703,75 8.796,86 Germany 1.012,44 8 1.943,89 24.298,63 Greece 82,10 8 157,63 1.970,40 Ireland 30,71 8 58,98 737,26 Lettonia 22,97 8 44,11 551,42 Liechtenstein 0,20 8 0,40 4,99 Luxemburg 11,34 8 21,78 272,23 www.albedocontrol.it
  26. 26. Cool Materials: Uses 3rd Discussion Groups’ Meeting 24-25 November, 2011,Athens, Greece Roof & Façade Coatings Protective Coatings Mortars PavementTiles Plasters…and many more
  27. 27. 3rd Discussion Groups’ Meeting 24-25 November, 2011,Athens, Greece Cool Materials: Policies, Initiatives, Legislation…
  28. 28.  • ASHRAE Standard 90.1-2007 prescribes cool materials for low-sloped roofs on nonresidential buildings in some U.S. climates.  • ASHRAE Standards 90.1-2004 and 90.1-2001 offer credits for cool materials for low sloped roofs on nonresidential buildings in some U.S. climates.  • ASHRAE Standard 90.2-2004 offers credits for cool materials for all roofs on residential buildings in some U.S. climate zones.  •The 2008 CaliforniaTitle 24 Standards prescribe cool materials for roofs on residential and nonresidential buildings in some California climate zones.  •The 2005 CaliforniaTitle 24 Standards prescribe cool materials for low-sloped roofs on nonresidential buildings in all California climate zones (but one coastal region) and offers credits for steep-sloped roofs on residential and nonresidential buildings in all California climate zones.  •The 2003 International Energy Conservation Code allows commercial buildings to comply by satisfying the requirements of ASHRAE Standard 90.1, which at the time that IECC 2003 was written offered cool-roof credits.  •The Chicago, IL Energy Conservation Code prescribes a minimum solar reflectance and thermal emittance for low-sloped roofs.  •The 2004 Florida Building Code prescribes cool materials for all roofs on non residential buildings that are essentially the same as those in ASHRAE Standard 90.1- 2004.  • Hawaii. In 2001, 2002, and 2005, respectively, the counties of Honolulu, Kauai, and Maui adopted cool-roof credits for commercial and high-rise residential buildings based on ASHRAE Standard 90.1-1999.  • U.S. EPA ENERGY STAR™ Label.The U.S. EPA currently requires that low-sloped roofing products have initial and three-year- aged solar reflectances not less than 0.65 and 0.50, respectively. Steep-sloped roofing products must have initial and three-year-aged solar reflectances not less than 0.25 and 0.15, respectively.  • LEED Green Building Rating System.The Leadership in Energy and Environmental Design (LEED) Green Building Rating System assigns one rating point for the use of a cool roof in its Sustainable Sites Credit.  • Green Guide for Health Care:The Green Guide for Health Care is a best practices guide for healthy and sustainable building design, construction, and operations for the healthcare industry. Cool Materials: Legislation and Policies… 3rd Discussion Groups’ Meeting 24-25 November, 2011,Athens, Greece
  29. 29. Cool Materials: References  Sanna Jaronen & Markku Oksanen, Uncivil Engineering the Serious Problem with Further Climate Tinkering, Science Progress, Oct. 5, 2009, http:// www.scienceprogress.org/2009/10/uncivil-engineering/ (last visited Feb.10, 2010) (explaining how geoengineering can be implemented to increase the Earth’s reflectivity).  Geoengineering Projects, supra note 21.  U.S. Energy Secretary Dr. Steven Chu on the benefits of using white roofs, http://www.youtube.com/watch?v=5wDIkKroOUQ (last visited Feb. 10, 2010).  Arthur Rosenfeld, Presentation to the annual California Air Resources Board’s Hagen-Smit Symposium: Cool Roofs: From Cool Cities to a Cooler World (June 3, 2009), available at http://www.energy.ca.gov/commissioners/ rosenfeld_docs/index.html.  U.S. Environmental Protection Agency, Heat Island Effect, http://www.epa.gov/hiri/index.htm, (last visited Feb. 10, 2010)  U.S. Environmental Protection Agency, Cool Pavements, http://www.epa.gov/hiri/mitigation/pavements.htm (last visited Feb. 12, 2010).  Cambridge Systematics, Cool Pavement Report (2005), available at http://www.epa.gov/hiri/resources/pdf/CoolPavementReport_Former%20Guide_complete pdf (prepared for the U.S. Environmental Protection Agency).  http://www.coolroofs.org/  http://www.epa.gov/heatisld/mitigation/coolroofs.htm  http://coolroofs.univ-lr.fr/  http://spie.org/documents/Newsroom/Imported/0777/0777-2007-06-22.pdf  www.globalcoolcities.org/  http://www.iea.org/work/workshopdetail.asp?WS_ID=278  http://www.iea.org/weo/database_electricity/WEO2005-Chapter%206.pdf  http://www.intechopen.com/source/pdfs/12173/InTech-On_the_effect_of_global_warming_and_the_uae_built_environment.pdf  http://www.scribd.com/doc/54930440/Climate-Related-Electricity-Demand-Side-Management-in-Oil-Exporting-Countries-The-Case-of-the-United-Arab- Emirates 3rd Discussion Groups’ Meeting 24-25 November, 2011,Athens, Greece
  30. 30. Cool Materials: A Video Presentation 3rd Discussion Groups’ Meeting 24-25 November, 2011,Athens, Greece
  31. 31. 3rd Discussion Groups’ Meeting 24-25 November, 2011,Athens, Greece Cool and Photocatalytic Construction Materials Manufacturer, Athens Greece Urbanus Green Innovations Cyprus Ltd (U.G.I Cyprus) operates as a sustainable management consultant and as a raw materials supplier.U.G.I focuses on the promotion of specifications and standards into national and local construction codes and on the supply of high performance raw materials for the industrial and construction sector. Prokopis Perdikis U.G.I CYPRUS/ABOLIN CO GREECE Marketing Committee Leader European Cool Roofs Council Email: abolin@otenet.gr, ugi.cyprus@gmail.com Thank you for your attention !

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