被动式太阳能集热构造在建筑设计中的应用

介绍了被动式太阳能构造的原理,并对其构造及经济价值进行了分析,并结合具体的设计实例,指出被动式太阳能采暖方式适用于北方偏远不适宜集中供热且温度要求较低的建筑,以减少很多的建设投资,且无运行成本,有很好的经济效益。     

Energy modeling of two office buildings with data center for green building design

Energy simulation models are developed with EnergyPlus for two office buildings in a R&D center in Shanghai, China to evaluate the energy cost savings of green building design options compared with the baseline building. As a R&D center of an international IT corporation, there are data centers in the two buildings, which make them different from typical office buildings. The data centers house high energy consuming IT equipments and need 24 h air-conditioning every day all year round. In order to achieve energy cost savings, multiple energy efficiency strategies are employed for design proposed building, encompassing high performance building envelope, lighting system, and HVAC system. Through energy modeling, the design proposed options are compared to an ASHRAE 90.1-2004 compliant budget model to highlight energy cost savings versus “standard practice” and show the potential LEED™ Credit EA1—Optimize Energy Performance. Meanwhile, they are also compared to China Code model to figure out the energy cost savings versus the most popular practice conforming to China Public Building Energy Saving Design Standard. The whole building energy simulation results show that the yearly energy cost saving of the proposed design will be approximately 27% from China Code building and 21% from ASHRAE budget building, which can achieve 4 points for LEED credit due to energy performance optimization.     

Retrofit cost-effectiveness: Estonian apartment buildings

The economic viability and investment cost of the energy retrofit of apartment buildings are analysed through different energy efficiency levels. To analyse retrofit policy cost-optimal energy efficiency levels and investment costs, a baseline of measured actual energy usage of apartment buildings was created and then individual energy-saving measures and retrofit packages were composed. The cost-optimal level over a 20-year period for apartment building retrofit was a low-energy-building energy performance level, with an investment cost of €150–170/m². Retrofit to low energy building level would be economically viable but the investment capability of apartment owner associations is found to be insufficient for the necessary investments to achieve low-energy-building energy performance. Therefore, it is necessary to determine what levels of financial support can encourage retrofit to occur. The analysis of the current retrofit shows that subsides will increase investment by apartment owner associations into energy efficiency improvements. The target group for energy efficiency retrofit subsidies should be apartment buildings that reach low energy building performance level or at least match the energy performance requirement for new buildings.     

Performance assessment of low-energy buildings in central Argentina

This paper summarizes the results obtained from the energy and thermal performance assessment of residential and non-residential low-energy buildings that were designed to minimize fossil energy use. They are located in the province of La Pampa, central Argentina, in a temperate continental climate that shows extreme hot and cold records during the summer and winter seasons, respectively. The common applied technologies for saving energy were passive solar heating, natural ventilation for cooling and daylighting. The glazing area in the principal functional spaces facing to the North oscillates between 11 and 17% of the building useful areas. All the studied buildings are massive, with the exception of an auditorium that was designed with a lightweight insulated technology. The mean thermal transmittance of the envelope is 0.45 W/(m² K). Double glazing and hermetic carpentry were used to reduce thermal losses (U-value = 2.8 W/(m² K)). The volumetric heat loss coefficient (G-value) oscillates between 0.90 and 1.00 W/(m³ K). During the design and thermal simulation convective-radiative heat transfer coefficients were estimated through a dimensional equation (h = 5.7 + 3.8 ws, wind speed). On internal surfaces, convective-radiative heat transfer coefficients of 8 and 6 W/(m² °C) (for surfaces with and without solar gain, respectively) were applied. The monitoring process provided information on the energy and thermal behaviour under use and non-use conditions. The measured value of energy consumption was similar to the expected value that was used during the pre-design stage. Building technologies work well during the winter season, allowing 50–80% of energy savings. However, overheating is still an unresolved problem during the summer. Interviews with occupants revealed that they need both, information about functional details, and good-practice guidance to manage thermal issues of the building. In most cases, the annual consumption of energy was lower than those established by the Low Energy Housing German Standards and the Minirgie Switzerland Certificate. Despite their relative cost increase during the last years, the use of insulation technology and the application of passive solar devices involved an extra cost of only 3% in our works. Provided the expected depletion of natural gas production in the coming decade, the importance of applying energy-efficiency guidelines will increase very soon in Argentina in order to match the requirements of a new national energy matrix.     

《可再生能源建筑应用项目系统能效检测标准》解读

重庆市《可再生能源建筑应用项目系统能效检测标准》于2014年7月1日起正式实施。在大量工程检测经验的基础上,结合重庆地区地方特色,制定了适用于该地区的可再生能源建筑应用项目系统能效的检测标准。该标准可应用于太阳能热利用系统、太阳能光伏系统和地源热泵系统的新建、扩建和改建工程,其检测方案能够达到国内先进水平。该标准为可再生能源建筑应用项目系统能效检测提供规范化的支持,显著提高检测效率,对于促进重庆市建筑节能事业的健康发展,具有极为重要的意义。     

Solar and heat pump system—Horsens swimming bath,Denmark

Over a number of years the local authorities of Horsens granted money to effect energy saving measures, the most cost-effective projects to be carried out first.

Recently a combined solar system and heat pump system has been constructed together with a centralized control and supervision system.

The solar system consists of 300 m² flat plate solar collectors without cover glass and insulation. The heat pump system consists of two water-to-water heat pumps with a total effect of 70 kW.

The total investment in the combined solar and heat pump system has been £93 000 (Dkr1.3m) including grants from the EEC and from the Danish Energy Administration.

The plant has now been in operation for more than 1 year and based on the measuring equipment installed it may be stated that the energy plant has given a saving of 2.8 TJ (670 Gcal) from district heating in the first year which allowing for a use of electricity of 187 MWh, amounts to a total of £14 000 (Dkr 195 000).

Based on a total investment of Dkr l.3m a yearly saving of Dkr 195 000 has been achieved, and speaking of an alternative energy plant this must be regarded as most satisfactory.     

Low energy houses

Domestic buildings absorb about 1/4 to 1/3 of the UK's primary energy. New houses can be designed which use half, or even considerably less than half of the energy consumed by their contemporaries. Typical examples are the Danish Zero Energy House and the Saskatchewan House. Unfortunately the U.K. building industry and its clients generally ignore long-run costs, in favour of lower initial capital investment. Such a position favours insulation and passive solar techniques, as opposed to more complex methods, for reducing network energy consumption in buildings.     

零碳排放住宅:金斯潘住宅案例分析

作为英国第一个设计和建造均达到"可持续住宅规范"中最高标准的示范案例,金斯潘住宅成功地向公众和建筑从业人员展示出"零碳排放住宅",即英国至2016年时所有新建住宅必须达到的标准,是能够在实际项目中实现的。本文在简单介绍"可持续住宅规范"后,对金斯潘住宅的案例分析探讨了在系统运用现有节能减排技术的基础上,实现零碳排放住宅的可行性。     

Energy Cost Burdens for Low-Income and Minority Households

Abstract

Problem, research strategy, and findings: Of the three primary components of housing affordability measures—rent, transportation, and utilities—utility costs are the least understood yet are the one area where the cost burden can be reduced without household relocation. Existing data sources to estimate energy costs are limited to surveys with small samples and low spatial and temporal resolution, such as the American Housing Survey and the Residential Energy Consumption Survey. In this study, we present a new method for small-area estimates of household energy cost burdens (ECBs) that leverages actual building energy use data for approximately 13,000 multifamily properties across five U.S. cities and links energy costs to savings opportunities by analyzing 3,000 energy audit reports. We examine differentials in cost burdens across household demographic and socioeconomic characteristics and analyze spatial, regional, and building-level variations in energy use and expenditures. Our results show the average low-income household has an ECB of 7%, whereas higher income households have an average burden of 2%. Notably, even within defined income bands, minority households experience higher ECBs than non-Hispanic White households. For lower income households, low-cost energy improvements could reduce energy costs by as much as $1,500 per year.

Takeaway for practice: In this study we attempt to shift the focus of energy efficiency investments to their impact on household cost burdens and overall housing affordability. Our analysis explores new and unique data generated from measurement-driven urban energy policies and shows low-income households disproportionately bear the burden of poor-quality and energy-inefficient housing. Cities can use these new data resources and methods to develop equity-based energy policies that treat energy efficiency and climate mitigation as issues of environmental justice and that apply data-driven, targeted policies to improve quality of life for the most vulnerable urban residents.     

加拿大卡尔加里市Okotoks小镇太阳能小区建设

简要介绍了北美目前最大的跨季太阳能储存项目——加拿大0kotoks小镇的太阳能小区建设，对其太阳能供热系统的工作原理及利用土壤床作为储能体进行大规模跨季节太阳能储存的方法进行了分析。该项目根据不同季节可利用太阳能数量的不同，分别设置了短期（临时）太阳能储箱（STTS）及跨季节太阳能储存箱（BTES），以提高太阳能的利用率。其中，BTES的效率可达50％以上。小区太阳能家用热水系统（DWH）可满足住户60％的热水需求，而太阳能采暖系统则可满足90％采暖要求；建成后每幢住宅每年可减排5t温室气体，整个小区可减排260t／年。     

浅谈太阳能建筑一体化在福建的应用

太阳能与建筑一体化是将太阳能利用设施与建筑有机结合,利用太阳能集热器替代屋顶覆盖层或替代屋顶保温层,即部分立面外墙、护栏、窗玻璃与建筑融为一体的完美结合,既消除了太阳能对建筑物立面的影响,又减少了重复投资,降低了成本。太阳能与建筑一体化是未来太阳能技术和节能环保建筑发展的方向。     

既有办公建筑节能改造技术经济效果分析研究

既有建筑节能改造是建筑节能工作的重要任务.以山东省某办公大楼节能改造试点经验为基础,对谊建筑改造后的节能率、节能投资、节能收益及投资回收期进行了分析研究,其结果可供既有建筑节能改造借鉴.     

Applying a multi-objective optimization approach for Design of low-emission cost-effective dwellings

Modern buildings and their HVAC systems are required to be not only energy-efficient but also produce fewer economical and environmental impacts while adhering to an ever-increasing demand for better environment. Research shows that building regulations which depend mainly on building envelope requirements do not guarantee the best environmental and economical solutions. In the current study, a modified multi-objective optimization approach based on Genetic Algorithm is proposed and combined with IDA ICE (building performance simulation program). The combination is used to minimize the carbon dioxide equivalent (CO₂-eq) emissions and the investment cost for a two-storey house and its HVAC system. Heating/cooling energy source, heat recovery type, and six building envelope parameters are considered as design variables. The modified optimization approach performed efficiently with the three studied cases, which address different summer overheating levels, and a set of optimal combinations (Pareto front) was achieved for each case. It is concluded that: (1) compared with initial design, 32% less CO₂-eq emissions and 26% lower investment cost solution could be achieved, (2) the type of heating energy source has a marked influence on the optimal solutions, (3) the influence of the external wall, roof, and floor insulation thickness as well as the window U-value on the energy consumption and thermal comfort level can be reduced into an overall building U-value, (4) to avoid much of summer overheating, dwellings which have insufficient natural ventilation measures could require less insulation than the standard (inconsistent with energy saving requirements) and/or additional cost for shading option.     

Observed energy savings from appliance efficiency standards

No country has directly measured the actual energy savings resulting from efficiency standards, but many studies—mostly in North America—have indirectly observed savings. Methodological and practical obstacles to observing savings include the difficulty of defining baseline energy use and isolating the impact of technical improvements in efficiency from other changes in usage patterns. Laboratory measurements are cheaper and faster than field measurements, but they still must be calibrated to field use. Energy savings resulting from refrigerator efficiency improvements have been the most closely examined. Savings have been observed through laboratory comparisons, field measurements, and utility bill analysis. Actual savings correspond closely to those predicted in laboratory tests. Reductions in energy use from improvements in efficiency have also been observed for both heating and cooling equipment. Laboratory-measured differences in efficiency generally give accurate estimates of percentage savings, but give poor estimates of absolute savings. Energy savings from efficiency improvements have also been observed for freezers, water heaters, and showerheads. The generally large percentage savings observed in North America may also apply to Europe and Japan although the absolute savings will be smaller. Savings from new standards created in these countries must be verified.     

节能技术在德国太阳能示范小区的应用

德国是世界太阳能利用大国,而EEG是推动德国太阳能市场发展最重要的动力.对于建筑节能,德国最大的手笔是建造太阳能住宅并且集成大量节能技术.以德国乌尔姆市的太阳能示范小区为例,介绍了各种节能技术在住宅中的应用,并结合中国当前节能减排的现状,探讨了德国太阳能示范小区给我们带来的思考与启示.     

Primary energy implications of end-use energy efficiency measures in district heated buildings

In this study we explore the effects of end-use energy efficiency measures on different district heat production systems with combined heat and power (CHP) plants for base load production and heat-only boilers for peak and medium load productions. We model four minimum cost district heat production systems based on four environmental taxation scenarios, plus a reference district heat system used in Östersund, Sweden. We analyze the primary energy use and the cost of district heat production for each system. We then analyze the primary energy implications of end-use energy efficiency measures applied to a case-study apartment building, taking into account the reduced district heat demand, reduced cogenerated electricity and increased electricity use due to ventilation heat recovery. We find that district heat production cost in optimally-designed production systems is not sensitive to environmental taxation. The primary energy savings of end-use energy efficiency measures depend on the characteristics of the district heat production system and the type of end-use energy efficiency measures. Energy efficiency measures that reduce more of peak load than base load production give higher primary energy savings, because the primary energy efficiency is higher for CHP plants than for boilers. This study shows the importance of analyzing both the demand and supply sides as well as their interaction in order to minimize the primary energy use of district heated buildings.     

Estimating the effect of using cool coatings on energy loads and thermal comfort in residential buildings in various climatic conditions

The impact from using cool roof coatings on the cooling and heating loads and the indoor thermal comfort conditions of residential buildings for various climatic conditions is estimated. The energy cooling loads and peak cooling demands are estimated for different values of roof solar reflectance and roof U-value. The results show that increasing the roof solar reflectance reduces cooling loads by 18–93% and peak cooling demand in air-conditioned buildings by 11–27%. The indoor thermal comfort conditions were improved by decreasing the hours of discomfort by 9–100% and the maximum temperatures in non air-conditioned residential buildings by 1.2–3.3 °C. These reductions were found to be more important for poorly or non-insulated buildings. For the locations studied, the heating penalty (0.2–17 kWh/m² year) was less important than the cooling load reduction (9–48 kWh/m² year). The application of cool roof coatings is an effective, minimal cost and easy to use technique that contributes to the energy efficiency and the thermal comfort of buildings.     

太阳能热泵供热系统的应用及经济性分析

以0.7 MW的供热功率为评价标准,分别对太阳能热泵、燃油锅炉、燃气锅炉和电加热锅炉四种供热系统进行了初期投资、运行费用、燃料价格等因素的综合技术经济分析与评价,评价结果表明：太阳能热泵供热系统的综合效果最好,适合在青岛推广应用。     

Coal,oil, or clean energy: Which contributes most to the low energy efficiency in China?

The lack of energy efficiency in China is always of interest. This paper builds a total-factor energy efficiency framework which contains coal energy, oil energy, and clean energy, which emits fewer pollutants into the atmosphere when used. We study the “China Statistical Yearbook” and the “China Energy Statistical Yearbook” to identify which type of energy contributes most to low energy efficiency in China. Our conclusion is that the total-factor energy efficiency (TFEE) in China has been at a relatively low level without any significant improvement from 1998 to 2010. The efficiencies of coal and oil energy have improved moderately, while there is no obvious improvement in the efficiency of clean energy. Despite the moderately improved efficiency of coal energy, its relatively low level contributes most to the overall energy inefficiency because it is the main fuel used in China. Further, the lack of improvements in the efficiency of clean energy makes it another area of policy interest.     

Vom Niedrigenergie‐ zum Nullenergiehaus: Standortbestimmung und Entwicklungsperspektiven

Der Begriff “Nullenergiehaus” ist in den letzten Jahren national und international zum Inbegriff für die konsequente Zusammenführung von Maßnahmen zur drastischen Energieeinsparung und optimierter dezentraler Nutzung erneuerbarer Energien geworden. Dabei geht es nicht um energieautarke Gebäude und die dabei große Herausforderung der saisonalen Energiespeicherung. Grundidee ist, dass die von einem Gebäude in ein Netz eingespeiste Energiemenge in der Jahresbilanz mindestens dem Energiebezug entspricht. Plusenergiehäuser erzielen eine positive Bilanz. Trotz Verankerung in zahlreichen energiepolitischen Positionspapieren existiert aber bisher keine Definition oder normative Beschreibung. Der Beitrag erläutert in einem internationalen Kontext die Hintergründe und diskutiert die Einflussgrößen bei der Bilanzierung. Nach Darstellung der normativen Berechnungszusammenhänge wird eine abgestimmte Terminologie und nationale Vorgehensweise vorgeschlagen. Diese berücksichtigt neben der Energiebilanz die Energieeffizienz und die Eigenbedarfsdeckung. From Low‐Energy to Zero‐Energy Building: Status and Perspectives. ”Net Zero Energy Building” has become a prominent wording to describe the synergy of energy efficient building and renewable energy utilization to reach a balanced energy budget over a yearly cycle. Taking into account the energy exchange with a grid infrastructure overcomes the limitations of energy autonomous buildings with the need for seasonal energy storage on‐site. Even though the wording ”Net Zero Energy Building” occurs in many energy policy documents a harmonized definition or a balancing method is still missing. The paper reports on the background and the various effects influencing the energy balance approach. After discussing the national energy code framework in Germany a harmonized terminology and balancing procedure is suggested. Besides the energy balance the procedure takes load energy efficiency and matching into account.