低坡屋顶，白色-CaliforniaEnergyCommission.ppt

1、From Local Cooling to Global Cooling: Cool Roofs and Cool Pavements 从地方冷却到全球冷却：冷屋顶和冷铺路面,Art RosenfeldCalifornia Energy Commissioner 美国加州能源专员Tel: 916-654-4930Email: ARosenfeEnergy.State.CA.UShttp:/www.energy.ca.gov*For more detailed information, please contact Hashem Akbari: *如欲获得更多详细信息，请联系Hashem Akb

2、ari: Tel: 510-486-4287E_mail: H_AkbariLBL.govhttp:/HeatIsland.LBL.gov,1,Temperature Trends in Downtown Los Angeles 洛杉矶市中心的气候变化曲线,每年高温,年,2,每年高温,3,White is cool in Bermuda在百慕大：白色是很“酷”的,4,and in Santorini, Greece在希腊的圣托里尼岛也是这样,5,Cool Roof Technologies冷屋顶技术,flat, white平顶，白色,pitched, white低坡屋顶，白色,pitched,

3、 cool & colored低坡屋顶，降温 & 多彩,Old 老一代技术,New 新一代技术,6,Cool Roof Programs around the World世界范围内的冷屋顶项目,U.S. 美国Europe 欧洲Asia 亚洲Middle East 中东China 中国India (Hyderabad demos; see graph at right) 印度 （在海德拉巴市示范，见右图）,东部（度/天）,西部（度/天）,西部建筑和东部建筑的每天空调用电量,前 后,7,Cool Colors Reflect Invisible Near-Infrared Sunlight冷色可以

4、反射看不见的近红外日光,标准化的太阳能强度,波长（纳米）,紫外线,可见光,近红外光,太阳能分布,5%来自紫外线,43%来自可见光,52%来自近红外光,8,Cool and Standard BrownMetal Roofing Panels对比：两块金属屋顶面板冷色的棕色和标准的棕色,Solar reflectance 0.2 higher太阳辐射反射率 0.2 以上Afternoon surface temperature 10C lower午后表面温度 低于10C,CourtesyBASFCoatings感谢BASF公司,冷色,标准色,冷棕色太阳反射率=0.27,标准棕色太阳反射率=0.0

5、8,反射率,波长（纳米）,太阳反射率=0.27热辐射率=0.85屋顶温度与空气温度之差为：36 C,太阳反射率=0.08热辐射率=0.85屋顶温度与空气温度之差为：45 C,Designing Cool Colored Roofing设计彩色的冷屋顶,冷色粘土瓦cool clay tileR 0.40CourtesyMCA Clay Tile感谢MCA Clay Tile 公司提供,冷色金属cool metalR 0.30CourtesyBASF IndustrialCoatings感谢BASF公司提供,冷色玻璃纤维沥青屋顶板（shingle）cool fiberglass asphalt s

6、hingleR 0.25Courtesy Elk Corporation感谢 Elk公司,9,冷色混凝土瓦,9,Cool is Cool: From Cool Color Roofs to Cool Color Cars and Cool Color Jackets冷色就是“酷”：从彩色的冷屋顶、冷轿车，再到冷外套,Toyota experiment (surface temperature 10C cooler)丰田公司的实验表明：冷色轿车的表面温度要比标准色轿车低10CFord is also working on the technology福特公司也正在研究这项技术,Courtesy:

7、 BMW (http:/www.ips- BMW 宝马汽车公司,10,10,Cool Paving Materials:冷铺路面材料,11,Reflective Pavements are Cooler反射路面温度更低，更“酷”,Fresh asphalt 新铺的沥青路面Albedo反照率: 0.05Temperature: 123F温度：52.8C,Aged asphalt 老旧的沥青路面Albedo反照率: 0.15Temperature: 115F温度：46C,Prototype asphalt coating 沥青涂层样品Albedo 反照率: 0.51Temperature: 88F

8、温度：31C,12,Temperature Effect on Rutting,507RF: 50C512RF: 40C,failure criterion,50C (122F),40C (104F),0,Repetitions (thousands),40,80,120,160,201612840,Rut Depth (mm),Source: Dr. John Harvey, UC B Civil Engineering, Inst. Transpo. Studies,13,Simulated Meteorology and Air-quality Impacts in LA 洛杉矶的模拟气

9、象和空气质量影响,气温变化,臭氧浓度变化,14,Potential Savings in LA (1998)Current costs have more than doubled* *Source: Rosenfeld et al. Energy and Buildings (28), p51-62, 1998 洛杉矶的潜在节余能力 (1998年)目前的成本是1998年的2倍*来源： Rosenfeld et al. Energy and Buildings (28), p51-62, 1998,Savings for Los Angeles (1998) 洛杉矶的节余金额：Direct,

10、$100M/year 直接节省：1亿美元/年Indirect, $70M/year 间接节省：7千万美元/年Smog, $360M/year 烟雾节省：3亿6千万美元/年 Estimate of national savings: $5B/year 据估计，全美国的节余金额为： 50亿美元/年,15,Indirect间接,Direct直接,Health 健康,Buildings 房屋,Cool Surfaces also Cool the Globe冷色表面也能让全球降温,Cool roof standards are designed to reduce a/c demand, save m

11、oney, and save emissions. In Los Angeles they will eventually save $100,000 per hour根据设计标准，冷屋顶可降低住户对空调的需求，既省钱又减排。在洛杉矶，冷屋顶最终可以实现每小时节约10万美元Annual savings in the U.S. = $1-2B; 7 M tons CO2冷屋顶在全美国的年度节余金额为：10-20亿美元；约700万吨CO2Annual savings in the world = $10-15B; 100 M tons CO2冷屋顶在全世界的年度节余金额为：100-150亿美元；约

12、1亿吨CO2BUT higher albedo surfaces (roofs and pavements) directly cool the world quite independent of avoided CO2. 但是! 高反照率的表面（如冷屋顶和冷铺路面）虽然可以直接降低温度，但却与减少CO2排放量没有直接联系,16,Solar Reflective Surfaces Also Cool the Globe太阳能反射表面也能让全球变得更凉爽,Source: IPCC图片来源：IPCC （ 政府间气候变化专门委员会）,17,Effect of Solar Reflective Ro

13、ofs and Pavements in Cooling the Globe太阳能反射屋顶和路面对全球降温的作用,(Source: Akbari, Menon, Rosenfeld. Climatic Change, 2008)（来源： Akbari, Menon, Rosenfeld. Climatic Change, 2008）,White Roof will be “diluted” by cool colored roofs of lower reflectivity, and roofs that can not be changed, because they are long-l

14、ived tile, or perhaps they are already white. 白色屋顶被有更低反射率的冷彩色屋顶“冲淡”了，而且房顶一般不会改变，因为他们是长寿命的瓦片，或者他们已经是白色的了。Compare 10 tons with a family car, which emits 4 tons/year. 可以把这10吨抵消的CO2，与一辆家庭用车比较。一辆家庭用车每年排放4吨CO2 。,*,*,*,*,18,A Global Action Plan: The Big Picture从全局来看：全球行动计划,Develop an international to insta

15、ll cool roof/pavement in worlds100 largest cities建立一个国际项目，在世界最大的100个城市中安装冷屋顶或冷铺路面This is a simple measure that we hope to organize the world to implement AND这是一项比较简单的措施，因此我们希望能够联合世界各国来实践它， 而且WED BETTER BE SUCCESSFUL!我们应该更好地让这个计划成功！We can gain practical experience in design of global measures to combat climate change我们可以在设计全球规模的措施中，获得实践中的经验教训，从而对抗气候变化,19,100 m2 of a white roof, replacing a dark roof, offset the emission of 10 tons of CO2 每用100平方米的白色屋顶替代黑色屋顶，就可以抵消10吨的CO2,Now remember this 请记得,20,