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Energy conversation of uPVC windows and doors

Time : 2022-03-18 Hits : 6

Characteristics of uPVC windows and doors

With the rapid development of construction in the world, building energy-saving design has become a very heated topic. At present, nearly 30 per cent of the world's energy is consumed in buildings, which, in the long run, will seriously affect the sustainable development of the world economy.


The energy consumption of buildings (including construction energy consumption, domestic energy consumption, heating and air conditioning, etc.) accounts for about 30% of the total energy consumption of the whole society, of which the most important is heating and air conditioning, accounting for 20%. However, this "30%" is only the proportion of energy consumed in the construction and use of buildings. If the energy consumed in the production of building materials (accounting for 16.7% of the total energy consumption of the whole society) is added, the energy consumption related to buildings will account for 46.7% of the total energy consumption of the society. At present, among the 2 billion square meters of newly built houses in China every year, most of them are high-energy buildings; among the 43 billion square meters of existing buildings, only 4% take energy efficiency measures, and the heating energy consumption per unit building area is more than three times that of newly built buildings in developed countries. Without strong measures, China's building energy consumption will be three times higher by 2020. According to the building energy efficiency survey data submitted by the CPPCC National Committee at the end of 2006, according to the current trend, the building energy consumption in China will reach 1.09 billion tons of standard coal by 2020.What does 1.09 billion tons of standard coal mean? It is equivalent to 400 times the reasonable inventory of coal for Beijing's five largest power plants.Each ton of standard coal is equivalent to about 2,700 kWh of electricity according to the power generation cost of China; in 2020, the building energy consumption of China will reach 2943 billion kWh, more than the total power generation of Three Gorges Power Station in 34 years.

With the increasingly severe energy situation in China, building energy efficiency has become an important means of building a land-saving society in China. In the field, windows and doors of buildings become the bottleneck of building energy efficiency.

According to the different climate and heating degrees&days(HDD), China is divided into five climatic regions, from north to south, which are: severe cold region, cold region, hot summer& cold winter region, hot summer & warm winter region and mild region. According to the index requirements specified in the Design Standard for Energy Efficiency of Public Buildings (B50189) and the Design Standard for Energy Efficiency of Residential Buildings (B50189), different regions have different indexes for doors and windows. The Design Standard for Energy Efficiency of Residential Buildings not only specifies the indexes, but also specifies the climatic regions of A, B and even C, and details the energy efficiency indexes of different regions.

Climatic   regionsCriterion
Severe   cold regionA5500 ≤ HDD18 < 8000
B5000 ≤ HDD18 < 5500  
C3800 ≤ HDD18 < 5000
Cold   region    A2000 ≤ HDD18 < 3800,   CDD26 ≤ 100
B2000 ≤   HDD18 < 3800,  100 < CDD26 ≤ 200
Hot   summer & cold winter regionA1000 ≤ HDD18 < 2000,  50 < CDD26 ≤ 150
B1000 ≤ HDD18 < 2000,  150 < CDD26 ≤ 300  
C600 ≤ HDD18 < 1000,  100 < CDD26 ≤ 300
Hot   summer & warm winter regionAHDD18 <  600,  CDD26 > 200
Mild   region    A600 ≤ HDD18  < 2000,  CDD26 ≤  50
B   HDD18 <  600,  CDD26 ≤  50

Energy saving requirements for doors and windows

 For EU countries, the Energy Conservation Act (ENEV)2009 standard stipulates that the whole window U-Wert ≤1.40 W/m2K, reaching a level of 1.10 W/m2K in 2010 and 0.9 W/m2K in 2012 

Insulation value of doors and windows

WindowGlassWindow   frame(sash)area ratioThermal   transmittance                                        W/(m2•K)Energy   efficient                                        %
Common Aluminum alloy windowsSingle   pane30%6.20
Double   glazing(5+9+5)4.1433.3
Low-E   insulating glass(5+12+5)3.0650.7
Thermally   broken Aluminum windowSingle   pane30%5.4612
Double   glazing(5+9+5)3.346.8
Low-E   insulating glass(5+12+5)2.3262.6
uPVC   windowSingle   pane35%4.724.2
Double   glazing(5+9+5)2.7855.2
Low-E   insulating glass(5+12+5)1.7871.3

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