conditions and found that black painted envelopes resulted in up to
7 ◦C (per unit volume of interior space) higher temperature than the
corresponding white painted envelopes. Uemoto et al. [6] showed
that cool colored paint formulations produced significantly higher
near infrared radiation reflectance than conventional paints of sim-
ilar colors, and measured a more than 10 ◦C reduction in surfacetemperatureswhen exposed to infrared radiation. Reagan and Ack-
lam[7] calculated the total building heat gain reduction when roof
surface reflectivity increased from 0.35 to 0.75. In July, the reduc-
tions were 6.4% and 4.8% in Tucson, Arizona with ceiling thermal
resistances of 2.5 and 5.88m2 K/W respectively. Griggs [8] found
up to 65% reduction in heat flux through a white roof compared to
black roof with the same thermal resistances of 1.32m2 K/W.
1.2. Previous experimental studies—the impact of reflective
coatings on energy consumption and peak demand
Several published articles focus on the potential reduction in
energy consumption for air conditioning and peak demand, which
are important parts of energy costs. Energy consumption and peak
demand savings with reflective coatings strongly depend on cli-
matic conditions (except for the envelope and coating material
properties and space type/configuration). Most studies were con-
ducted in California: Akbari et al. [9] compared cooling energy
and peak power consumption of two identical school bungalows
with different roof reflectivities and found a 3.1 kWh (35%) sav-
ings in cooling energy as well as 0.6 kWpeak demand savings with
reflective roofs. They also concluded [10] that increasing the roof
reflectance of commercial buildings in California from about 20%
to 60% decreased the roof temperature on hot summer afternoons
by 7.2 ◦C. In another study [11], they reported electricity savings of
0.5 kWh/day (or 33Wh/m2/day) by increasing roof reflectivity from
26% to 72%, which translates into annual energy savings of about
125 kWh. For the same location, Hildebrandt et al. [12] measured
daily air-conditioning savings of 17%, 26% and 39% in an office, a
museum and a hospital with high reflectivity roofs. Parker et al.
[13]monitored six homes in Florida before and after application of
high-albedo coatings on their roofs. Reduction in air-conditioning
electricity consumption was measured between 11% and 43% with
an average saving of 9.2 kWh/day, and reduction in peak power
demand (occurs between 5 and 6 pm)was 0.4–1.0 kWwith an aver-
age reduction of 0.7 kW. They also monitored seven retail stores
within a strip mall in Florida. After applying a reflective roof coat-
ing, a 7.5Wh/m2 (25%) drop in daily summertime cooling-energy
use and a 0.65W/m2 (29%) decrease in demand were realized [14].
Akridge [15] reported daily savings of 75Wh/m2 (28%) for an edu-
cation building in Georgia by painting the galvanized roof with
white acrylic coating. The same researcher [16] also measured
a reduction of 33 ◦C in peak roof temperature of a single storey
building after application of a thermal control coating. In Nevada,
Akbari and Rainer [17] measured daily air-conditioning energy
savings of 33Wh/m2 (only 1%) in two telecommunication regen-
eration buildings. In Texas, Konopacki and Akbari [18] measured
daily energy savings of 39Wh/m2 (11%) and peak-power reduction
of 3.8W/m2 (14%) in a large retail store when a reflective mem-
brane was used. Energy savings in an office building in Mississippi
reached 22% after application of a reflective roof coating [19].In
Hong Kong, Cheung et al. [20] showed that 30% reduction in solar
absorptance can achieve 12% saving in annual required cooling
- 上一篇:自然通风英文文献和翻译
- 下一篇:真空电弧沉积系统英文文献和翻译
-
-
-
-
-
-
-
酸性水汽提装置总汽提塔设计+CAD图纸
中考体育项目与体育教学合理结合的研究
乳业同业并购式全产业链...
大众媒体对公共政策制定的影响
杂拟谷盗体内共生菌沃尔...
十二层带中心支撑钢结构...
java+mysql车辆管理系统的设计+源代码
河岸冲刷和泥沙淤积的监测国内外研究现状
电站锅炉暖风器设计任务书
当代大学生慈善意识研究+文献综述