论述建筑节能设计的问题和措施
文章主要就我市建筑节能设计存在的问题进行探讨和交流，分析了我市的节能设计中主要存在的问题，并结合多年设计实践经验提出了几点节能措施。
关键词 建筑设计；节能；措施
在发展低碳经济的道路上，建筑的节能和低碳注定成为绕不开的话题。低碳建筑已逐渐成为国际建筑界的主流趋势。在我国二氧化碳排放中有40% 来自于建筑，建筑业还是占地大户，仅以住宅面积为例，我国城镇和村镇住房面积2008年底达到530多亿平方米，我国要实现节能低碳的目标，如果建筑业不作为，至少是半句空话。在我国能耗结构中，建筑能耗占社会总能耗近三之一，据调查，我国楼宇年电力消耗总量占全国总消耗量的10%，能源费用超过800亿元，单位建筑面积能耗比世界头号耗能大国美国2004年平均水平多出30%以上。楼宇建筑是能源消耗的主要领域。目前我国建筑业物质消耗占全部物质消耗总量的15%左右，建筑能耗约占全社会能耗的30%。同时，我国建筑耗能的效率仅为发达国家的30%左右，建筑节能的空间很大。
1 建筑设计中的问题
1）部分建筑节能不合理。对于我市的住宅小区，由于空调的启停与人的活动密切相关，这点与北方有很大的差别，所以空调设备不是住宅节能的主要问题。住宅小区最突出的问题是在规划阶段和初步设计阶段很少根据夏季主导风向进行小区的自然通风模拟，并根据结果进行小区的合理规划。由于布局不当而造成的部分建筑自然通风不良的并不少见。建筑单体的自然通风也未受到普遍的重视。许多建筑设计大面积的窗户，而开启部分的面积却很小。由于缺乏
能耗，而且对健康不利。自然通风优良的住宅，开空调的时间可以大大减少，空调的能耗也会大大降低。由于可以少关闭窗户，居室内的空气质量自然也就好了。所以，小区的规划和建筑自然通风的设计，是与室内热环境和人们的健康有密切的关系，也是建筑节能设计的重要环节，而这一环节在我市的许多小区设计中或单体设计中被严重疏忽的地方。同时，许多建筑在建筑设计阶段，建筑师对其进行过必要的节能设计，对建筑的布局、朝向、体形、间距、组团布置及墙身、屋顶、地面、门窗等围护结构的构造、选材、热工指标曾按照国家规范的要求进行了考虑。然而，在进行建筑采暖设计时，设计人员不按照建筑节能设计计算所得的耗热（冷）量指标确定采暖（空调）设备的数量，甚至根本不考虑房屋建筑已经采取的节能措施，仍然一如既往地按非节能建筑进行设计，或者是有考虑，但不是按设计计算结果执行，而是加以过大的保险系数。结果这样所谓的节能建筑投入使用后，与普通建筑相比在能耗上并不节省，或者略有节省但效果不够明显，即人们常说节能建筑不节能。
2）建筑外遮阳不合理。随着节能技术的推广，建筑行业对建筑外遮阳也越来越重视。建筑外遮阳能有效地阻隔部分太阳光直接照射到建筑物的外围结构，特别是防止太阳辐射穿过窗户直接进入室内，从而有效降低室内温度，达到节能的最终目标。在实际设计中，设计师经常会为了达到造型效果而刻意增加立面上的装饰构板，这些构件由于并非从遮阳方面考虑，所以形式作用大于实际功能。这并不符合设计的经济原则和节能原则。
3）太阳能的利用不足。我市具有丰富的光、热资源。但在我市的建筑设计中，充分利用太阳能这一大自然免费提供的光热资源的设计理念尚未完全进入
即便有一些设计中考虑了太阳能，也是极为简单和初级的。同时，设计人员对新型的太阳能设施、设备的性能指标及各类参数不了解、不熟悉，自然在设计时也就不会采用此类节能设备。
2 建筑节能措施
2.1 设计者必须优化建筑位置及朝向设计
在方案设计中，建筑师需要对建筑的方位、体型、朝向进行优化，为充分利用自然风、阳光等自然资源创造条件。同时，从方案设计开始到初步设计，工程师需要根据不断调整的设计方案模拟量化建筑的能耗情况，计算空调和各类设备的装机功率，比对各种影响因素，严格按设计计算结果执行，最后提供最佳的节能设计方案。
2.2 建筑立面设计应与建筑外遮阳设计相结合
1）要明确各种外遮阳的适用性。建筑外遮阳的设置与太阳的位置、建筑物的朝向都有着密切的关系。在窗户遮阳方面，实践证明:水平遮阳能遮挡高度角较大、从上方入射的太阳光，适用于南向的窗户；垂直遮阳能遮挡高度角较小、从侧面斜入射的太阳光，适用于东北向、西北向和正北向的窗户；综合遮阳则综合了水平与垂直遮阳的优点，适用于东南向、西南向和正南向的窗户。此外，挡板式遮阳、帘式遮阳、百叶遮阳等方式对于窗户遮阳都有非常好的效果，但对建筑采光则有一定的影响。而对于建筑墙体和屋面的遮阳，目前较为有效的方法是通过栅格遮阳和绿化遮阳。随着社会经济水平的不断提高，建筑遮阳技术已越来越趋向智能化、自动化、高效化。
2）要从构件的设计上合理处理好遮阳与隔热的问题。传统的实体构件 水平、垂直和综合遮阳与墙体相连，其吸收的热量会直接传递给外墙，而且容易
传热由空气带走并向上传递，但由于其它遮阳构件的阻挡，反而容易产生积聚现象，在风的作用下通过窗户导入建筑室内，从而不利于隔热。解决的方法是在水平遮阳构件的选择上采用通透性的构件，如金属百叶、混凝土栅格板等，使上升的热空气能有效地散失，减少对室内的影响。目前较为先进的双层玻璃幕墙系统中，为了利于热空气的上升，其两层玻璃幕墙间的空气夹层往往是一个可连续的整体，即垂直方向上的间隔均为通透的金属构件，确保热空气能上升并带走热量。因此，在遮阳构件的选择上要细致研究，不断更新设计。
3）要合理设置遮阳板，避免影响室内空气的流动速度。因为遮阳板的存在会对建筑物周围的风压产生影响，当其角度与风向不一致时，风速将会大大降低。实践证明，由于设置了遮阳板，室内风速会减弱22%~47%。而且，遮阳的设置方式也会对气流产生不同的影响。如实体水平遮阳板直接连接在窗顶，气流进入室内后会上升，不利于房间中下部的通风。若在实体板与墙体间增加空隙，或在遮阳板上部的墙体流出通风口，又或将遮阳板设在高于窗顶一段距离的位置，都能使得气流的方向得到有效的调节，使房间中部和下部均得到良好的通风，提高室内环境的舒适性。而对于垂直遮阳来说，由于风向是经常变化的，所以固定的垂直遮阳板应顺应所在地夏季的主导风来设置相应的角度，而更好的方法是采用可调节的垂直遮阳板，使建筑最大限度地适应气候的变化。
2.3 要加强设计人员的专项学习
相关管理部门及设计审查部门应加大对太阳能节能设计的审查，凡属可利用太阳能设施节能的，均应建议采用，通过行政手段强制推行太阳能 这一我市得天独厚的资源 节能措施。
3 结束语
建筑节能是一个复杂的系统工程，涉及方方面面的问题。上文所提及的三方面问题只是其中的一部分，在我市的节能设计中，它们往往不被重视甚至被忽视，这会造成许多的设计漏洞，使建筑物能耗增加。本文专门把它们选出来进行探讨，正是为了集思广益，共同探讨建筑节能设计的新方法，在今后的设计中多研究、多尝试、多积累、多总结，在有限的条件下将建筑功能与艺术和技术更好地结合，使建筑设计的各个方面都能体现节能的原则，努力创造低成本、高效率的节能建筑。
The article with respect to the our city building energy conservation design problems to explore and exchange, analyzes the city \'s energy-saving design main problems, combined with years of design experience puts forward some energy saving measures.In the Key words: architectural design; energy saving measures; In the development of low carbon economy, energy saving and low carbon destined to be not open around the topic.Low carbon building has gradually become the mainstream trend of international construction industry.In China\'s carbon dioxide emiions in 40% from a building, construction industry or area of large family, only to residential area as an example, China\'s urban and rural housing area reached about 53000000000 square meters by the end of 2008, our country should realize energy saving and low carbon target, if the industry is not as, at least half empty.In China\'s energy consumption structure, building energy consumption accounted for nearly three of social total energy consumption, according to the survey, China\'s building power consumption accounted for 10% of the total consumption, energy costs over $80000000000, energy consumption of unit building area than the world\'s largest energy-consuming country the United States in 2004 30% more than the average level.The building energy consumption is the main field.
our country construction material consumption accounted for about 15% of the total material consumption, building energy consumption accounts for about 30% of the whole society energy consumption.At the same time, China\'s building energy efficiency is only 30% in developed countries, building energy saving of large space.1 problems in the design of 1) part of building energy saving is not reasonable.For the city of residential air conditioning, because the start-stop is closely related to human activities, this and the north are very different, so air conditioning equipment is not the main problem of residential energy saving.Residential quarters of the most outstanding iue is in the stage of planning and preliminary design phase, according to the prevailing wind direction in summer are rarely residential natural ventilation simulation, and according to the results of the plot plan.Because of the layout of improper part of the building natural ventilation are not uncommon.Single building natural ventilation is not widespread attention.Many architectural windows, and the opening part of the area is very small.Due to the lack of natural ventilation, air current not free, a lot of time need air conditioning, indoor air quality is poor, not only increases the energy consumption, and bad for the health.Natural ventilation admirable residence, open air conditioning time can
greatly reduced.Due to le closed windows, indoor air quality is good.Therefore, the area of planning and building natural ventilation design, and indoor thermal environment and people\'s health is closely related to, but also the important link of building energy-saving design, but this link in the city\'s many small design or monomer design are serious negligence place.At the same time, many of the buildings in the design stage, the architect on the neceary of building energy-saving design, layout, orientation, shape, spacing, travel arrangement and wall, roof, floor, doors and windows and other enclosure structure, material selection, thermal indicators have according to national standard requirements were considered.However, in building heating design, design personnel in accordance with the building energy saving design calculated heat ( cold ) index to determine heating (air conditioning) the amount of equipment, and did not even consider building has the energy saving measures of as in the past, still according to non energy saving building design, or are considered, but not according to the design calculation results of execution, but to be exceive insurance coefficient.The results of such so-called energy-saving building is put into use, different from ordinary building on energy consumption does not save or save slightly, but the effect is not quite apparent, that is often said that energy saving building energy saving.
of energy-saving technology, the construction industry on the sun outside the building are more and more attention.Building exterior shading can effectively prevent part of solar light irradiation to the periphery of building structure, especially to prevent solar radiation through the window directly into the chamber, thereby effectively reducing the indoor temperature, to achieve the end goal of saving.In the actual design, designers often in order to achieve the shape effect and deliberately increase on the facade decoration board structure, these components as not from the sun into consideration, so the form effect is greater than the actual function.This is not consistent with the design of the economy principle and the energy saving principle.3) the use of solar energy shortage.Our city has abundant light, heat resource.But in our architectural design, make full use of solar energy in the nature of light and heat resources are provided free of charge design concept has not yet been fully into the minds of the designers, even if there are some design considerations of solar energy, is also extremely simple and primary.At the same time, the design of novel solar energy facilities, equipment performance and various parameters do not understand, not familiar with the nature in the design, it would not have used such energy-saving equipment.
2.1 designer must optimize the position and orientation of architectural design In the project design, architects need to building orientation, shape, direction optimization, in order to make full use of natural wind, sun and other natural resources to create the conditions.At the same time, from programme design to the preliminary design, engineers need to constantly adjust the design simulation of building energy consumption calculation of quantification, air-conditioning and equipment installed power, ratio of various influencing factors, in strict accordance with the results of the design calculations, finally provides the best energy saving design.The 2.2 elevation of the building design should be combined with the design and building external solar shading 1) to clear all kinds of external sun-shading applicability.Building exterior shading settings and the position of the sun, building orientation are closely related.The window shade, practice has proved that: the horizontal sunshade capable of shielding angle is larger, from the top of incident sunlight, applicable to the south window; vertical shading can keep the height angle is small, from the side of the oblique
light from the sun, applicable to the northeast, northwest and north to the window; overall shading of the level and vertical shading advantages, applicable to the southeast, southwest and south to windows.In addition, the baffle type sunshade, curtain type sunshade, sunshade for window sunshade, has very good results, but the building will have a certain effect.As for building wall and roof sunshade, more effective method is through the grid and green visor visor.With the continuous improvement of social economy, building shading technology has more and more intelligent, automation, high efficiency.2) from the component design and reasonable deal with sunshade and heat insulation problems.The traditional entity component level, vertical and sunshade and wall are connected, the absorbed heat will be paed directly to the exterior, but also constitute a half open space, sunshade component by solar radiation temperature rise, a part of the heat through the heat transfer from air to pa away, but due to other sunshade component of the block, but prone to accumulation phenomenon, under the action of wind through the window into the interior, which is not conducive to heat.The solution is in the horizontal sunshade component is chosen as the permeability of the components, such as metal louvers, concrete grid plate, so that the rising hot air can be effectively diipated, reducing on indoor effect.The advanced double gla curtain wall system, in order to hot air rises, the two layers of gla curtain
and the air between the interlayer is often a continuous whole, i.e.vertical intervals are permeable metal components, to ensure that the hot air can rise up and take the heat.Therefore, the sunshade component selection to meticulous research, constantly updated design.3) should be arranged reasonably visor, avoid the influence of indoor air flow.Because of the existence of the visor of buildings around the preure impact, when the angle and direction of inconsistencies, wind speed will be reduced greatly.Practice has proved that, due to the setting of the sun visor, indoor weaken 22% ~ 47%.Moreover, shade settings will have different effects on the flow.If the entity level visor is connected directly to the window top, air into the room after the rise, is not conducive to the room in the lower part of the ventilation.If the solid plate and wall between the increased gap, or in the upper part of the wall out of the visor vent, or the sun visor in each position some distance above the window, can make the airflow direction can be effectively regulated, so that the room is middle and lower parts are good ventilation, improving the comfort of the indoor environment.But for the vertical shading, as the wind direction changes frequently, so the fixed vertical visor should comply with local summer prevailing wind to set the corresponding angles, and a better method is to use the adjustable vertical visor, construction maximum adaptation to climate change.
Management departments and related design review department should increase pair of solar energy-saving design review, where can use solar energy facilities, shall be proposed, through administrative means to force the implementation of solar this city be richly endowed by nature resources and energy saving measures.The 3 ending Building energy saving is a complex system engineering, involved in all aspects of the problem.The above mentioned three problems is just one part of it, in the city\'s energy-saving design, they are often ignored or neglected, it will cause many design flaws, make the building energy consumption increase.This paper devoted to them all out to carry on the discuion, it is to benefit by mutual discuion, discu jointly building energy saving design method, the design in the future study, try, accumulation, summed up, in the limited condition of the architectural function with art and technology to better integrate, make the architecture design in all aspects can embodiment of the principle of energy conservation, efforts to create a low cost, high efficiency and energy saving construction.
