With the rapid changes in science and technology, energy shortages can not be ignored, energy conservation has been a universal concern worldwide, in our country is no exception. At present, nearly 30% of the world's energy consumption in buildings, in the long run, will seriously affect the sustainable development of the world economy. Therefore, the energy issue will become the hot topic of this century, we must start from the strategy of sustainable development, so that the building as little as possible to consume non-renewable resources, reduce the pollution of the external environment, and provide users with healthy, comfortable, and natural harmony of the work and living space.
A foreign energy-saving has become a trend
1. Resource recycling
A U.S. university has designed and built a four-bedroom eco-house. Its thermal energy comes from artificial heat, sunlight and the use of home appliances produced by the heat; electricity rely on wind turbines and solar cells; water from the eaves of the rain water after treatment; manure and sewage into a compost pit, after fermentation for the garden fertilizer. In the United States, a construction company uses recycled garbage to build houses, with walls made of recycled tires and aluminum scrap; most of the steel used for the roof frames is recycled from construction sites; the panels used are made of sawdust and shredded wood, plus 20 per cent polyethylene; and old newspapers and cardboard boxes become the main raw material for roofing and serve as insulation for the walls. The headquarters of the U.S. National Resources Defense Council is a green office built with recycled materials from used and recycled goods as the main material. Its walls are made of straw pressed and processed with high technology, the floor is made of waste glass, and the desks are made of waste newspaper and soybean residue. In addition, it has large windows, so that the office is very bright, thus saving 30% of electricity. In Japan, an experimental "healthy house" was built in 1997. In addition to the whole house as far as possible to choose harmless building materials, the wall is also designed as a double structure, each room is built with a vent, the whole house system of air using total heat exchanger and dehumidifier for the return loop. The total heat exchanger effectively recovers heat and reuses it, and its filter effectively collects fine dust in the air, thus inhibiting the reproduction of allergic organisms such as mold. This recycling of resources not only turns waste into treasure, but also reduces environmental pollutants and saves energy.
2. New energy development and utilization
German architect Saido? German architect Saido Tejols built a solar house that can track the sun. The house is mounted on a disk base with a set of gears driven by a small solar motor. The base of the house rotates with the sun on a circular track at a rate of 3cm per minute. When the sun sets, the house reverses its rotation and returns to its starting position. The power it consumes to track the sun is only 1% of the house's solar power, while the solar energy it absorbs is equivalent to two times that of a solar house that can't generally rotate. Germany also has a zero-energy housing, 100% of the energy required by solar energy. Zero-energy housing open to the south of the plane is designed as a fan-shaped plane, you can get a very high solar radiation energy. The walls are made of gray sandstone bricks with good heat storage capacity, insulation and decorative materials, the sunlight passes through the insulation material and the heat is stored in the gray sandstone brick walls. The house is heated by the sun through the windows during the day, and at night it is heated by the insulation material and the gray sand brick wall.
3. Paper building
Paper as a structural material can not only reduce the weight of the building, speed up construction, reduce costs; and after the building is dismantled, the paper can be reused, saving resources, environmental protection is also beneficial. The world has a number of temporary and semi-temporary buildings built with paper structure. Located in Switzerland, a paper tower is a meaningful example of lightweight construction, the paper tower outside diameter of 13m, 33m high, completed in 1992, has become a local landmark building in Switzerland. The materials used for the whole tower are 79.26% cardboard, 20.22% wood and 0.52% steel. The use of biodegradable materials for the building opened up a "green" channel, so they are known as "green building" model. 2000 World Expo, the Japan Pavilion is a temporary paper building used during the World Expo, most of the materials can be recycled after the meeting. Most of the materials can be recycled after the Expo. It focuses on resource and environmental issues through the theme of material and structural properties. It was built using recycled paper in the form of an arched cylinder structure made of a mesh of 12.5cm thick paper tubes, and the curved roof and wall materials were also fabric and paper film. The pavilion is 72m long, 32m wide, the highest place up to 15.5m, an area of 3600m2. during the day, the natural light through the translucent paper window filtering constitutes a soft, pleasant indoor light environment; at night, the paper window is a magical light and shadow of the "screen". In the Expo Pavilion, natural light shines through the waterproof fabric and the roof made of paper film, creating a space environment rich in Japanese flavor. The Japan Pavilion reflects the ecological and environmental awareness of the Japanese people in general, and the significance of this paper structure not only lies in environmental protection and energy saving, but more importantly, it provides a quick way to solve the problem of human habitation.
Second, the basic situation of China's building energy consumption
China's building energy consumption accounts for about 1/4 of the country's total energy consumption, ranking first in energy consumption. In recent years, China's construction industry has been rapid development, requiring a large number of construction and implementation of the use of energy, especially heating and air conditioning building energy consumption. According to statistics, in 1994 the national only residential building energy consumption in the case of basically no hot water for 1.54 × 108t standard coal, accounting for 12.6% of the total social energy consumption of 12.27 × 109t standard coal. At present, each year, urban buildings only heating a need to consume 1.3 × 108t standard coal, accounting for about 11.5% of the total national energy consumption, accounting for more than 20% of the heating area of the whole society energy consumption, in some cold areas, urban building energy consumption up to about 50% of the local social energy consumption [1]. At the same time, due to the building heating combustion of large amounts of coal and other fossil energy, so that the surrounding natural and ecological environment continues to deteriorate. In the process of energy utilization, 99% of the NOx, 99% of the CO, 91% of the SO2, 78% of the CO2, 60% of the dust, and 43% of the hydrocarbons emitted into the atmosphere during the combustion of fossil fuels, of which coal combustion produces the majority. Coal combustion produces 87% of SO2, 67% of NOx, 71% of CO2 and 60% of soot as air pollutants [2]. Since China is a country that mainly consumes coal as its main energy source instead of oil, gas and other high-quality energy sources, the annual carbon dioxide emissions to the earth's atmosphere due to the combustion of fossil fuels are the second highest in the world after the U.S. It is expected that by 2020, China will replace the U.S. as the world's top emitter of carbon dioxide. Therefore, China bears a great responsibility for global warming, and as a major energy-consuming building, its energy saving has become a major issue for the people of China.
China's energy saving work compared with developed countries started late, and energy waste is very serious. Such as China's building heating heat consumption: the outer wall is largely close to the climatic conditions of the developed countries of 4 to 5 times, the roof for 2.5 to 5.5 times, the windows for 1.5 to 2.2 times; windows and doors permeability for 3 to 6 times; total energy consumption is 3 to 4 times [4]. If we allow high energy-consuming buildings to flourish, building energy consumption will grow much faster than the rate of possible growth in China's energy production, the country's energy production will inevitably be difficult to support this wasteful demand in the long term, and thus have to organize a large-scale energy-saving renovation of the old house will cost more manpower and material resources. In addition, tens of millions of new and renovated buildings each year to consume billions of tons of forest, masonry and mineral materials, resulting in excessive deforestation, large-scale exploitation of material resources, bringing about the destruction of land, degradation of vegetation, species reduction and deterioration of the natural environment.
Third, several ways to save energy
1. Wall energy saving
The wall is the main body of the building envelope, the thermal insulation effectiveness of the materials used directly affect the building's heat consumption. China's solid clay bricks as wall materials, thermal insulation performance can not meet the design standards. Thus, under the premise of energy saving, should further promote the hollow brick wall and its composite wall technology.
2. Window and door energy saving
Windows and doors is the weakest part of the residential energy dissipation, its energy consumption accounted for a larger proportion of the total energy consumption of the residence, of which the heat loss of 1/3, cold air infiltration of 1/3, so in order to ensure that the sunshine, lighting, ventilation, viewing requirements of the conditions, try to minimize the area of the residential windows and doors of the hole, improve the airtightness of the external windows and doors to reduce the infiltration of cold air to enhance the exterior of the windows and doors themselves, reduce the thermal insulation efficiency, reduce the number of windows and doors. Doors and windows of its own thermal insulation efficiency, reduce the heat transfer of the external doors and windows themselves. Its energy-saving measures are:
(1) control of residential window-wall ratio.
(2) Improve the airtightness of residential windows to reduce cold air infiltration.
(3) Improve the thermal insulation efficiency of residential windows and doors.
(4) Set the "temperature damping zone".
3. Roof energy saving
In the continuous improvement of the building wall, external window insulation performance, must further strengthen the roof thermal insulation research. Roof energy-saving measures, one of the main points is the roof insulation layer should not choose a higher density, higher thermal conductivity of the insulation material; the second is the roof insulation layer should not choose a larger water absorption rate of the insulation material in order to prevent the roof wetting operations due to a large number of insulation layer water absorption and reduce the effect of thermal insulation, and now, high-efficiency thermal insulation materials have begun to be applied to the roof, the roof insulation of a number of buildings, the expansion of the expanded perlite insulation core insulation board insulation layer Instead of conventional asphalt perlite or cement perlite practices, to overcome the many shortcomings of conventional practices. This thermal insulation core board construction is convenient, inexpensive, not polluting the environment; core board for flexible products, not only for roofing with plane, can also be used for roofing with curved surfaces, its thermal insulation project can show its superiority.
4. Utilization of solar energy
The earth intercepts solar radiation energy equivalent to 1500 times the current global power consumption. And in the existing technical and economic conditions for the development and utilization of solar energy, only a small part of the theoretical resources. Therefore, the development and utilization of solar energy has great potential. Solar energy is mainly utilized in the building, passive solar heating, solar hot water, active solar heating and air conditioning, and solar power generation and so on. China is rich in solar energy resources, the land receives annual solar radiation energy, equivalent to 2.4 × 1012tec, if the sun's energy is fully utilized, not only is it possible to save a large amount of conventional energy, but also the possibility of using solar energy in some areas of the full heating.
5. Night ventilation
The principle of the night ventilation method is to introduce outdoor cold air at night, through the cold air and the building maintenance structure as a heat storage material contact heat transfer, cooling building materials, to achieve the purpose of cold storage. In summer, in order to obtain a comfortable indoor environment, the air conditioning cooling system is needed. At this time, because the outdoor air temperature at night is much lower than during the day, the cold outdoor air at night can be utilized as a good natural cold source. Strictly speaking, as long as the outdoor air temperature is lower than the indoor air temperature, the outdoor cold air at this time can be regarded as a natural cold source can be utilized.
What are the energy-saving technologies and the implementation of building energy-saving renovationTwelfth Five-Year Plan "period" of China's existing building renovation tasks
Edit
"Twelfth Five-Year Plan" period, the completion of the northern heating areas of existing residential buildings heating measurement and energy-saving renovation of more than 400 million square meters, hot summer and winter and hot summer and winter warm areas of existing residential buildings energy-saving renovation of 50 million square meters, the public*** Building energy-saving renovation of 60 million square meters;
The main contents of energy-saving renovation of existing buildings
Edit
Thermal insulation renovation of external walls, roofs, windows and doors, and other enclosure structures;
Renovation of the heating system of sub-household heat metering and room temperature regulation;
Energy-saving renovation of heat sources (boiler rooms or heat stations) and heat supply pipeline network;
Comprehensive energy-saving renovation involving building repair, functional improvement and adoption of renewable energy sources, etc.
Archives of standards related to energy-saving renovation of existing buildings
Editorial
Main evaluation standards
Green evaluation standards for renovation of existing buildings (in progress)
Main design standards
Energy-saving renovation of public **** buildings JGJ176-2009
Technical specification for energy-saving renovation of existing residential buildings
Masonry reinforcement design standard GB 50702
Technical specification for foundation reinforcement of existing buildings JGJ123-2000
Technical specification for earthquake-resistant reinforcement of buildings JGJ116
Investigation and design specification for repair works of civil buildings JGJ 117 and design regulations JGJ 117
Building energy-saving methods and measuresShould avoid standby appliances (a) Many people for the sake of convenience, after watching TV with the remote control off on everything, not realizing that this is just so that the TV is on standby, still cost a lot of electricity. The reporter learned from the Hebei Provincial Development and Reform Commission Resources Division, a variety of home appliances for a long time in standby mode, will accumulate a lot of power consumption. Television, for example, an average of 2 hours per day per TV standby, standby power consumption of 0.02 degrees (kWh), China's TV holdings 350 million units, a year of standby power consumption of up to 2.555 billion degrees, equivalent to several large-scale thermal power plants in a year of power generation total. In layman's terms, standby means turning off the remote control without turning off the electrical switch or power supply. Nowadays, most of the home appliances have standby function, each home appliance in the standby state power consumption is generally about 10% of its power on, about 5 watts -15 watts. The average urban resident family has a TV, air conditioning, stereo, microwave ovens, etc. standby energy consumption together, equivalent to open a 30 watts -50 watts of bright lights. Statistically estimated that the penetration rate of home appliances in towns and cities with a high penetration rate of home appliances per household per month standby power consumption of 20 degrees -40 degrees. It can be said that in daily life, behind the convenience of a moment, resulting in waste. Therefore, we should try not to make home appliances in standby mode, but to turn off the electrical switch, or completely turn off the power. How to correctly use energy-saving lamps (2) Energy-saving lamps are often used in the family of energy-saving products, then exactly how to correctly use energy-saving lamps, so that it achieves the best energy-saving effect it Reporters recently from the National Development and Reform ...
What information on building energy efficiency?
(a) new energy-saving wall and roof insulation, thermal insulation technology and materials;
(b) energy-saving doors and windows of thermal insulation and airtight technology;
(c) centralized heating and heat, electricity, cold cogeneration cogeneration technology;
(d) heating heating system temperature control and heat metering technology and devices;
(e) solar energy, geothermal renewable energy application technology and devices;
(e) solar energy, geothermal and other ... (E) solar, geothermal and other renewable energy application technologies and devices;
(F) building lighting energy-saving technologies and products;
(G) air conditioning and refrigeration energy-saving technologies and products;
(H) other mature technology, the effect of energy-saving technologies and energy-saving management techniques.
What are the methods of building energy efficiency?Building energy saving methods. Specific search: energy saving and emission reduction assessor Jiang Yu
What are the building energy saving measures?Envelope structure and lighting system
? Opaque parts such as external walls and roofs: improve thermal insulation efficiency and reduce energy consumption of heating and air-conditioning systems; adopt green roofs.
? Windows: shading and heat preservation; natural lighting, reducing its building lighting energy consumption; transition season, open windows for natural ventilation.
? Lighting system: Optimize the control of the lighting system by combining the natural lighting of the windows; personnel sensors to "turn off the lights when people leave".
? Internal and external movable sunshade: improve sunshade efficiency, reduce the load of air-conditioning system sunshade and natural lighting optimization design and control
Preventing glare
Cold and heat source system
? Select the appropriate cooling and heating source capacity, appropriate number of units, try to ensure that the unit in high efficiency: most of the units in the non-designed working conditions, improve the efficiency of part of the load implementation of the energy-saving effect will be very obvious.
? Selection of high-efficiency devices (cooling and heating sources, pumps, fans and ancillary equipment): optimization and evaluation of the efficiency of the device, price and maintenance costs, as well as benefits.
? Natural energy sources (solar, geothermal, underground or surface water): solar hot water systems utilizing underground or surface water, closed cooling towers
? Water (ice) cold storage technology, water heat storage technology: local electricity cost differentials and benefits
? Heat recovery technology (exhaust gas, exhaust air, condensate, cooling water and sewage, etc.): recovery of available waste heat and waste heat
? Seasonal cold storage: cold storage or ice cellar, etc.
Conveying system
? Water system for conveying hot and cold sources: higher conveying efficiency and energy saving compared to all-air system
? Increase the conveying temperature difference and reduce the conveying flow: the energy-saving effect is obvious, and the refrigerant temperature can be reduced by utilizing cold storage
? Variable flow technology: variable frequency fan or variable frequency pump
? Air conditioning system design: design and actual implementation of the same piping layout must be flat, smooth, straight, and thus reduce piping resistance
? Insulation and airtightness of piping: Adoption of optimal thickness of insulation layer to ensure airtightness of piping connection
Air-conditioning system
? VRV system: easy to manage and split slot execution
? Fan coil + fresh air system: easy to manage and split slot execution
? Whole air system (VAV system): rational system split slots, reduce its fan energy consumption
? Improvement of fresh air quality: Reduction of system fresh air volume
? System exhaust air reuse ：System exhaust air is used as supply air for machine rooms, parking lots or cooling towers
Control system
? Personnel sensing: Reduction of lighting energy consumption when no one is in the room, automatic control of VRV system on
? Optimal ratio execution of the device (number of units control and capacity allocation): load matching and operating number of units control
? Optimal start-up time and execution time: Optimization of start-up execution time and number of chiller execution leads
? Setting the optimal number of air supply leads (air supply volume and air supply status): improving the efficiency of the chiller
? Setting the optimal execution strategy according to the climate change (prediction): significant energy saving and ensuring the best quality in the room
? Programmed Scheduling Temperature: Automatically adjusts the indoor air conditioning set temperature according to indoor use
What are the methods for realizing building energy conservation? The same outdoor temperature, the use of external insulation of the house, the indoor temperature is less susceptible to environmental influences, which is not only conducive to building energy efficiency, but also to increase the comfort of the house. Young architects in Switzerland used to be opposed to external insulation, believing that it prevented them from expressing the beauty of the different wall materials used in a building. But now they have begun to like the design of external insulation, the new technology gives them more space to show their talent, and become their new opportunities and challenges.Third, we should pay attention to the closed envelope and mechanical ventilation with heat recovery devices. The role of airtight enclosure for energy saving is very obvious. Regulating the temperature in an airtight room has more energy for heating, and if coupled with a heat recovery device, the air temperature brought to the room by the ventilation unit is close to that of the room, which can save up to 60% of the electricity consumed by the air-conditioning system.
Fourth, we must pay attention to the coupling of the indoor environment. A Swiss study showed that the normal human body have 100 watts of energy, how to use the body's energy, so that the indoor temperature is better suited to the human body temperature, all need to pay attention to. In-situ retrofitting in-situ implementation of Switzerland in 1980 per square meter of the building's annual energy consumption is 20 liters of oil, many after the renovation of the building, as well as new buildings, the annual energy consumption is only 4 liters, while in China, this figure is currently 30 liters. The task of reducing this from 30 liters to 4 liters is very daunting.
All of the above content is based on the actual work of the students encountered problems organized for reference, if there is a problem, please communicate in a timely manner, corrections.
What are the new approaches to building energy efficiency?This question is a bit vague, try to answer:
Building energy efficiency mainly includes: wall masonry materials, wall and roof insulation, building windows and other energy-saving indicators
Also includes energy saving on the electrical lighting, the building's physical coefficient, etc.
What are the sub-projects of building energy efficiency1, wall energy-saving projects, the main structure of the grass-roots level; thermal insulation materials; finishing layer
2, curtain wall energy-saving projects main structure grass-roots level; thermal insulation materials; thermal insulation materials; vapor barrier; curtain wall glass; unit curtain wall panels; ventilation system; shading facilities; condensate collection and discharge systems, etc.
3, windows and doors energy-saving projects doors; windows; glass; shading facilities, etc.
4, roofing energy-saving projects grass-roots level; thermal insulation; protection layer; waterproof layer ; surface layer, etc.
5, ground energy-saving projects grass-roots level; thermal insulation; protective layer; surface layer, etc.
6, heating energy-saving projects system system; radiators; valves and meters; heat inlet device; insulation materials; in addition to the wrong
7, ventilation and air-conditioning energy-saving projects system; ventilation and air conditioning devices; valves and meters; adiabatic materials; in addition to the wrong
8, air conditioning and heating systems, cold and heat sources and pipe network energy-saving projects system system; cold and heat source devices; auxiliary devices; pipe network; valves and instruments; insulation; insulation materials; and error removal
9, power distribution and lighting energy-saving projects Low-voltage power supply distribution; lighting sources, lamps and lanterns; auxiliary devices; control functions; and error removal
10, monitoring and control of energy-saving projects Cold and heat source system monitoring and control system; air conditioning water system monitoring and control system; monitoring and control system; air conditioning water system. Monitoring and control system; air-conditioning water system monitoring and control system; ventilation and air-conditioning system monitoring and control system; monitoring and metering devices; power supply and distribution monitoring and control system; lighting automatic control system; integrated control system, etc.
What are the measures for energy saving in civil engineering buildings1, to improve the understanding of building energy saving
It is important to raise awareness of building energy saving under the basic concept of human-centeredness. Building energy efficiency awareness. Awareness of building energy efficiency, can not just stay in the past one-sided understanding of the stage, but should be from an all-round perspective to improve the understanding of building energy efficiency. Must correct the past kind of energy-saving building is to a certain extent to reduce the quality of the building and simple house, because building energy efficiency is not only to a certain extent to reduce the waste of raw materials in the construction process, but also to ensure that can not reduce the comfort of the house and people's sense of livability, the result of such a building is to put the cart before the horse. Therefore, our ultimate goal is: not to reduce the standard of housing, as far as possible to achieve the control of raw materials and resources used, and ultimately realize the purpose of not only does not damage the human-centered, but also to a certain extent to reduce the waste of resources.
2, must have a perfect management concept and the corresponding mechanism
Due to China's relatively late in the development of building energy efficiency, will meet a large number of problems in the process of implementation of building energy efficiency, if you want to improve the situation must have a perfect management concept and the corresponding mechanism. This requires the construction side and *** department coordination and cooperation. From the *** department, to strengthen the building energy-saving materials to foster the strength, and encourage the use of building energy-saving materials, in addition, should also be the help of the legislative department, due to the inclusion of the legislative department can be to a certain extent on the building energy-saving industry to carry out proper management, to promote the development of the building energy-saving industry. At the same time, we can learn from foreign advanced concepts of building energy-saving industry, but the premise must be combined with our actual situation, so as to accelerate the development of China's building energy-saving aspects of the program.
3, follow the trend of the times to update the technology
We are at this stage in the reference to foreign advanced concepts of energy-saving building industry at the same time, must be in the physical aspects of its match, otherwise it can not be achieved the same effect, so we must speed up the update of existing technology, so that as soon as possible in order to catch up with the advanced technology and concepts of foreign countries. We can not learn from the advanced concepts of foreign building energy-saving industry at the same time, ignoring the basic status quo based on China's building energy-saving technological innovation, we must adhere to the two-legged approach, one is to learn from the advanced concepts of building energy-saving industry with modification of foreign countries, and the other is to develop the basic status quo based on the building energy-saving technological innovation in our country, so that to a certain extent can be rapidly improve the quality and efficiency of the building to achieve the purpose of energy saving and emission reduction. The purpose of energy saving and emission reduction can be realized to a certain extent by rapidly improving the quality and efficiency of buildings. In addition, the use of high-efficiency materials must be used reasonably and effectively in the process. Finally, in the construction process, to eliminate the use of polluting materials, reasonable emission of harmful substances, to achieve the effective use of clean energy.