In the United States, university buildings use 17% of total non-residential building energy per year. According to the NREL (National Renewable Energy Laboratory), the average lifecycle of a building in a university...In the United States, university buildings use 17% of total non-residential building energy per year. According to the NREL (National Renewable Energy Laboratory), the average lifecycle of a building in a university is 42 years with an EUI (energy use intensity) of 23 kWh/m^2/y. Current building and energy codes limit the EUI to 16 kWh/m^2/y for new school buildings; this benchmark can vary depending on climate, occupancy, and other contextual factors. Although the LEED (leadership in energy and environmental design) system provides a set of guidelines to rate sustainable buildings, studies have shown that 28%-35% of the educational LEED-rated buildings use more energy than their conventional counterparts. This paper examines the issues specific to a LEED-rated design addition to an existing university building. The forum, a lecture hall expansion of to an existing building at the University of Kansas, has been proposed as environmentally friendly and energy-efficient building addition. Comfort and health aspects have been considered in the design in order to obtain LEED platinum certificate. The forum's energy performance strategies include a double-skin facade to reduce energy consumption and PV (photovoltaic) panels to generate onsite energy. This study considers various scenarios to meet NZEB (net-zero energy building) criteria and maximize energy savings. The feasibility of NZE criteria is evaluated for: (a) seasonal comparison; (b) facility occupancy; (c) PV panels' addition in relation to double skin facade. The results of NZEB approach are compared to LEED platinum requirements, based on Rol (return on investment) and PV panel's efficiency for this specific educational building.展开更多
Net-zero energy buildings and communities, which are receiving increasing interest, and the role of energy storage in them, are described. A net-zero energy building or community is defined as one that, in an average ...Net-zero energy buildings and communities, which are receiving increasing interest, and the role of energy storage in them, are described. A net-zero energy building or community is defined as one that, in an average year, produces as much energy from renewable energy as it consumes. Net-zero energy buildings and communities and the manner in which energy sustainability is facilitated by them are described and examples are given. Also, energy storage is discussed and the role and importance of energy storage as part of net-zero buildings and communities are explained. The NSERC Smart Net-zero Energy Buildings Research Network, a major Canadian research effort in smart net-zero energy buildings and communities, is described.展开更多
In recent years,large high efficiency and Net-Zero Energy Buildings(NZEB)are becoming a reality that are setting construction and energy benchmarks for the industry.As part of this significant effort,in 2018,Mohawk Co...In recent years,large high efficiency and Net-Zero Energy Buildings(NZEB)are becoming a reality that are setting construction and energy benchmarks for the industry.As part of this significant effort,in 2018,Mohawk College opened the 8,981 m^(2)(96,670 ft2)Joyce Centre for Partnership and Innovation(JCPI)building in Hamilton,Ontario;becoming Canada’s largest NZEB and zero-carbon institutional facility.The building integrated a high-efficiency design,construction materials,and technologies;as well as renewable energy technologies to significantly reduce its annual energy consumption and greenhouse gas emissions.Furthermore,the JCPI building was also designed as a living lab where students,faculty,researchers and industry are able to monitor and validate the performance of this state-of-the-art facility.The building was designed to have an energy use intensity of 73 kWh/m^(2)·year(0.26 GJ/m^(2)·year);hence,potentially consuming approximately 80%less energy than the average educational service building in Ontario.This paper gives an overview of the design criteria and technologies that were considered to achieve this innova-tive building.展开更多
INTRODUCTION The level of man-made CO_(2) emissions worldwide climbed to a new record of 30 billion tons in 2010.In 2011,at the COP17 U.N.Climate Change Conference in Durban,South Africa,high-ranking representatives f...INTRODUCTION The level of man-made CO_(2) emissions worldwide climbed to a new record of 30 billion tons in 2010.In 2011,at the COP17 U.N.Climate Change Conference in Durban,South Africa,high-ranking representatives from around the world met again to discuss solutions.For the building sector,numerous energy-efficiency market changes and benchmarking resolutions,like the mandatory E.U.“nearly Net-Zero-Energy-Building(NET-ZEB’s)2018 and 2020 regulations”for all new public and privately owned buildings are now set up to help minimizing carbon emissions and reverse the negative impact.1 In the United States,the American Institute of Architects(AIA)adopted the 2030 Challenge as a voluntary program,where participating buildings aim to achieve a 90%fossil fuel reduction by 2025,and carbon-neutrality by 2030.2 To accomplish these energy goals,designers must strive to best design and utilize the resources available on a site.However,are these goals of achieving carbon-neutral buildings possible?How can NET-ZEB’s become the curricular standard and practical routine in education and the profession?To date,the basic curricular design process components with integrated project delivery metrics for a robust 3-D/4-D-net-zero regulatory design framework are either incomplete or missing,However,formally-based curriculums have begun to weave carbon-neutral design tools into their pedagogy.This research paper critically compares how these new criteria for digital 3-D-building information modeling(BIM),and“Integrated Project Delivery”are mandating a better integration of collaborative carbon-neutral designs into the curriculum and practice of the profession.The majority of those in architectural academia have been using generative computation primarily for pure,aesthetic form-finding,without applying zero-carbon-energy-driven global performance metrics and CO_(2)e reduction strategies to reiterate derived carbon-neutral designs.The advantage of 3-D-parametric design is that it links variables,dimensions,and materials to geometry in a way that when an input or simulation value changes,the 3-D/4-D model automatically updates all life-cycle scenarios and components simultaneously.展开更多
Near-zero energy buildings( nZEBs) are considered as an effective solution to mitigating CO_2 emissions and reducing the energy usage in the building sector. A proper sizing of the nZEB systems( e. g. HVAC systems,ene...Near-zero energy buildings( nZEBs) are considered as an effective solution to mitigating CO_2 emissions and reducing the energy usage in the building sector. A proper sizing of the nZEB systems( e. g. HVAC systems,energy supply systems,energy storage systems, etc.) is essential for achieving the desired annual energy balance,thermal comfort,and grid independence. Two significant factors affecting the sizing of nZEB systems are the uncertainties confronted by the building usage condition and weather condition,and the degradation effects in nZEB system components. The former factor has been studied by many researchers; however,the impact of degradation is still neglected in most studies. Degradation is prevalent in energy components of nZEB and inevitably leads to the deterioration of nZEB life-cycle performance. As a result,neglecting the degradation effects may lead to a system design which can only achieve the desired performance at the beginning several years. This paper,therefore,proposes a life-cycle performance analysis( LCPA) method for investigating the impact of degradation on the longitudinal performance of the nZEBs. The method not only integrates the uncertainties in predicting building thermal load and weather condition,but also considers the degradation in the nZEB systems. Based on the proposed LCPA method,a two-stage method is proposed to improve the sizing of the nZEB systems.The study can improve the designers "understanding of the components"degradation impacts and the proposed method is effective in the life-cycle performance analysis and improvements of nZEBs. It is the first time that the impacts of degradation and uncertainties on nZEB LCP are analysed. Case studies showthat an nZEB might not fulfil its definition at all after some years due to component degradation,while the proposed two-stage design method can effectively alleviate this problem.展开更多
Conferences and publications on Smart Cities and self-styled ecological buildings such as“Vertical Forests”,“Biophilic”building complexes and other similar are multiplying.But then,in reality,we continue to design...Conferences and publications on Smart Cities and self-styled ecological buildings such as“Vertical Forests”,“Biophilic”building complexes and other similar are multiplying.But then,in reality,we continue to design as we have always done for the last ninety years:with the consolidated rules and formal solutions of international post-modern composition,in its various forms.The only attentions are(and not always)to super-insulate the envelopes,arrange photovoltaic panels on the roofs,make the systems smart and cover the facades and roofs with appropriate green washing.Even in the awareness that human settlements and cities are extremely complex phenomena,mostly determined by economic and social factors,rather than by conscious typological-settlement choices,perhaps the time has come to acknowledge that the traditional paradigms of design must be changed.First of all,the types of settlements must be renewed,because it is through their optimization that the greatest savings in terms of energy and sustainability can be achieved.The research presented here is the application of a ten-year study that involved the development of net Zero Energy Mass Custom Housing(ZEMCH)in specific context in southern Italy.The Innovation and Transparency of Tenders Environmental Compatibility(ITACA)Assessment Protocol,derived from the Green Building Challenge’s GBTool,was used as a design guide,which is normally used for the assessment and judgment of sustainability at the building scale and not of the urban design.The result is a settlement model in which network of pedestrian,cycle and public transport is fully integrated with adjacent urban areas;effective landscaping connects public and private green and kitchen-gardens/orchards everywhere;buildings are made with new semi-underground typologies;net ZEMCHs are made with local,recyclable materials with low impact or positive energy balance;wastewater and rainwater are collected,in-loco phyto-purified and reused;renewable energies(sun,earth,wind)satisfy remaining necessities,with a minimum of plant interventions.展开更多
This paper presents a simulation technology of environmental impact for the building. By emergy analysis method,emergy costs of building( or construction engineering) can be calculated in the life cycle. It includes t...This paper presents a simulation technology of environmental impact for the building. By emergy analysis method,emergy costs of building( or construction engineering) can be calculated in the life cycle. It includes the engineering cost, environmental cost and social cost of building. Through integrating GIS technology with multi-agent technology,life cycle substance and energy metabolism of building( construction engineering) can be simulated and their environmental influence can be dynamically displayed. Based on the case study of entries works‘Sunny Inside'by Xiamen University in 2013 China International Solar Decathlon Competition,we discovered the changing pattern of surrounding environmental impact from waste streams of the zero-energy building and ordinary construction. The simulation results verified and showed the Odum principles of maximum power. This paper provides a new research perspective and integration approach for the environmental impact assessment in building and construction engineering. The result will help decision-making in design and construction engineering scheme.展开更多
Decrease of energy consumption in buildings and increase of the share of renewable energies in them are currently technologically and economically feasible and it is promoted by E.U. policies. After 2019, all the new ...Decrease of energy consumption in buildings and increase of the share of renewable energies in them are currently technologically and economically feasible and it is promoted by E.U. policies. After 2019, all the new public buildings in EU countries must be near zero energy buildings reducing their energy consumption and CO<sub>2</sub> emissions. Use of various renewable energies for heat and power generation in school buildings in Crete-Greece can result in zeroing their fossil fuels consumption and CO<sub>2</sub> emissions. Purpose of the current work is to investigate the possibilities of creating zero CO<sub>2</sub> emissions school buildings in Crete-Greece due to operational energy use in them. A methodology which allows the replacement of fossil fuels with renewable energies in school buildings is proposed. Solar energy, solid biomass and low enthalpy geothermal energy, which are abundant in Crete, can be used for that. School buildings in Greece consume significantly less energy, 68 KWh/m<sup>2</sup> year, and emit less CO<sub>2</sub>, 28 kgCO<sub>2</sub>/m<sup>2</sup> year, than the corresponding buildings in other countries. The installation cost of renewable energies systems in order to replace all fossil fuels used in school buildings in Crete-Greece and to zero their CO<sub>2</sub> consumption due to energy use in them has been estimated at 47.42 - 87.71 €/m<sup>2</sup>, which corresponds to 1.69 - 3.13 €/kg CO<sub>2</sub> saved.展开更多
Nearly zero energy buildings (nZEB) will become an obligatory energy efficiency standard in Europe. Following to common guidelines in European legislation, the countries investigated technical and economic framework f...Nearly zero energy buildings (nZEB) will become an obligatory energy efficiency standard in Europe. Following to common guidelines in European legislation, the countries investigated technical and economic framework for the preparation of detailed national technical definition of nZEB. Slovenia accepted the nZEB criteria in early 2015. This paper describes the technical and economic background for identification of economically viable concepts of highly energy efficient apartment building. The highrise demonstration building Eco Silver House revealed that meeting nZEB standards was not an easy task, not so much for technical reasons, but mostly due to the processes, inadequate skills, not fully compliant regulation and insufficient possibilities for interaction between the building and energy networks. Analysis of cost effectiveness showed that the Eco Silver House fulfilled minimal requirements of cost-optimal for apartment building with Net Present Value of 272 EUR/m2 and Primary energy use of 79 kWh/ m2?a in line with the Slovenian national cost optimal study of minimum energy performance requirements from the year 2014. At the time, the requirement of 50% share of renewables in final energy use is not fulfilled, but will be easily reached when EU2020 energy efficiency targets set in the Slovenian Energy Act regarding the RES share in district heating systems and public power grid will be gradually implemented. The demonstration project FP7 EE-HIGHRISE confirms that in spite of the barriers, the nZEB minimum requirements defined on profound theoretical studies can be met in practice.展开更多
INTRODUCTION Recent development has seen a drastic increase in energy use trends in Saudi Arabian buildings leading to a demand for an effective course of action for energy conservation and production.A case study-bas...INTRODUCTION Recent development has seen a drastic increase in energy use trends in Saudi Arabian buildings leading to a demand for an effective course of action for energy conservation and production.A case study-based research initiative explor-ing near-zero energy potential in Saudi Arabia was undertaken.A 4-bedroom detached single-family faculty residence at King Fahd University of Petroleum and Minerals(KFUPM)representing common regional housing design trends was utilized.A base case simulation model of the house was developed and val-idated using short-term and real-time energy consumption data.Three sets of strategies:passive design strategies,representative codes and standards,and renewable technology were employed in the new design of the house.Passive strategies com-prised a green roof,a ventilated wall system,a sloped roof,and insulation for thermal bridges.These alternatives helped reduce the annual energy consumption of the house by 17.2%.The most recent version of the International Energy Conserva-tion Code(IECC 2012)was also incorporated along with ASHRAE Standard 62.2 for ventilation.The code and standard together reduced the annual energy consumption by 31.1%.Solar PV was then utilized to reduce grid utilization for the remainder of the house energy loads.This strategy provided 24.7%of the total energy consumed annually.A combination of strategies showed a 70.7%energy consumption reduction,thereby decreasing the energy index of the house from 162.9 to 47.7 kWh/m^(2)/yr.The Zero Energy Building(ZEB)concepts and strategies utilized in this study demonstrate a socially responsible approach to achieving near-zero energy performance for an existing house.展开更多
The goal of this work is to evaluate and to give evidence to innovative and sustainable technologies applied in the construction industry to carry out self-sufficient energy and to use the surplus energy for the produ...The goal of this work is to evaluate and to give evidence to innovative and sustainable technologies applied in the construction industry to carry out self-sufficient energy and to use the surplus energy for the production of hydrogen vector. An architectural integration design along with high technological systems is performed. The intermittency of renewable energy sources along with climatic conditions dependency imposes to store the energy produced, since it is clean and having a big calorific value: the hydrogen vector is currently the better energy carrier. The energy to obtain hydrogen by dissociation of water is supplied by a photovoltaic (PV) system. Through the computations of the annual energy balance between building’s demand and supply energy, it is shown that the extra energy produced by the solar generation system is used also for the hydrogen sustainable mobility. The renewable systems, model’s design and case study are tackled for the bigger one of the Dodecanese islands in the South Aegean Sea: Rhodes (Rodos). The Zero energy building’s integrative design-based approach, applied to the Hotel Buildings type industry is targeted to have new hotels buildings, in the Mediterranean typical warm climate, with zero energy consumption. The designers, authors of this work, have studied a real case or pilot project of an hotel, in the resort formula, suitable to the Greek landscape, showcasing technologies and innovations supporting environmental sustainability, energy efficiency, use of renewable energy, electricity storage by fuel cells that are tools particularly applicable to hotel facility [1]. The feasibility of this case study or pilot project is aligned jointly to the target of Zero Emission and Energy Efficiency EU Policy, as imposed by EU Directives. The strategic position of Rhodes in a geographical point full of sun and wind renewable energy power, enables to ensure the clean energy production, the current interesting development of the hydrogen as energy vector in the buildings [2] and also to satisfy the demand of tourists’ accommodation by having at the same time zero energy costs. Moreover, the presence in the island of the best example worldwide of ancient and sustainable built environment (UNESCO World Heritage site), represents also the best motivation to give witness there of a zero impact environmental urban development through the adoption of these achieved scientific results for a major success of Zero Energy Buildings.展开更多
Buildings contribute around 45%of the world’s energy consumption.Reducing energy demand in buildings therefore plays a vital role in addressing the depletion of energy resources and associated environmental issues.Pr...Buildings contribute around 45%of the world’s energy consumption.Reducing energy demand in buildings therefore plays a vital role in addressing the depletion of energy resources and associated environmental issues.Previous research explored the optimisations of the costs and energy consumption of buildings,but often overlooked the connections,tradeoffs and synergies between them.The aim of this paper is thus to develop a theoretical model of the influencing parameters of the life cycle cost-energy relationship(LCCER)of buildings using the Political,Economic,Sociocultural,Technological,Environmental and Legal(PESTEL)analytical framework.is study was carried out through a critical literature review,model development and validation through case studies with four zero or nearly zero energy building projects carefully selected from the European Union and Australia.The developed model addresses the buildings’LCCER by identifying the key influencing parameters and explicating the mechanisms(namely,the simultaneous and unilateral effects)by which the identified parameters affect such relationship.The important influencing parameters were found to reside in two aspects:(1)internal project designs covering building characteristics,building structure and function,and construction process,and(2)external environments covering climate,economic condition,occupant behaviour,policy and regulation,and buildings’lifespan focused in the studies.Various statistical correlations were found to exist between the costs and energy consumption of the studied cases.It is summarised that these correlations may be attributable to the synergy between the simultaneous and unilateral effects of the identified parameters.The developed model contributes a systemic approach to examining the building’s life cycle economics and energy in a comparative manner.展开更多
The Centre of Excellence at Okanagan College in Penticton,British Columbia is being designed as one of the most innovative and sustainable post-secondary facilities in the world.On schedule for design and construction...The Centre of Excellence at Okanagan College in Penticton,British Columbia is being designed as one of the most innovative and sustainable post-secondary facilities in the world.On schedule for design and construction to be complete by April 2011,the two-storey multi-purpose facility has a mandate to provide trades and technology training and professional development to students from the province of British Columbia and beyond.It is aimed at attaining the highest standard of sustainable building design,the Living Building Challenge.The building will support a syllabus with a focus on the design,installation,and support of sustainable building technologies and processes,and the development and application of alternative and renewable energy.The building itself will become an essential element of the educational programs that will reside there,a teaching tool for education on building trades and engineering technologies.In addition,the Okanagan Research Innovation Centre will be incorporated into the building,providing opportunities for start-up companies to develop and prototype new green technologies in a supportive and synergistic environment.This article will demonstrate that a project with this level of sustainable objectives is achievable at a cost comparable to conventional building design.It will address how this can be attained through an integrated design process,along with the numerous innovative features that have been incorporated into the building design to help it function with a small environmental impact,and a large educational one.展开更多
Energy consumption in buildings is considered a significant portion of gross power dissipation, so a great effort is required to design efficient construction. In severe hot weather conditions as Kuwait, energy requir...Energy consumption in buildings is considered a significant portion of gross power dissipation, so a great effort is required to design efficient construction. In severe hot weather conditions as Kuwait, energy required for building cooling and heating results in a huge energy loads and consumption and accordingly high emission rates of carbon dioxide. So, the main purpose of the current work is to convert the existing institutional building to near net-zero energy building (nNZEB) or into a net-zero energy building (NZEB). A combination of integrated high concentrated photovoltaic (HCPV) solar modules and evacuated tube collectors (ETC) are proposed to provide domestic water heating, electricity load as well as cooling consumption of an institutional facility. An equivalent circuit model for single diode is implemented to evaluate triple junction HCPV modules efficiency considering concentration level and temperature effects. A code compatible with TRNSYS subroutines is introduced to optimize evacuated tube collector efficiency. The developed models are validated through comparison with experimental data available from literature. The efficiency of integrated HCPV-ETC unit is optimized by varying the different system parameters. Transient simulation program (TRNSYS) is adapted to determine the performance of various parts of HCPV-ETC system. Furthermore, a theoretical code is introduced to evaluate the environmental effects of the proposed building when integrated with renewable energy systems. The integrated HCPV-ETC fully satisfies the energy required for building lighting and equipment. Utilizing HCPV modules of orientation 25? accomplishes a minimum energy payback time of about 8 years. Integrated solar absorption chiller provides about 64% of the annual air conditioning consumption needed for the studied building. The energy payback period (EPT) or solar cooling system is about 18 years which is significantly larger than that corresponding to HCPV due to the extra expenses of solar absorption system. The life cycle savings (LCS) of solar cooling absorption system is approximately $2400/year. Furthermore, levelized cost of energy of solar absorption cooling is $0.21/kWh. Hence, the net cost of the solar system after subtracting the CO2 emission cost will be close to the present price of conventional generation in Kuwait (about $0.17/kWh). Finally, the yearly CO2 emission avoided is approximately 543 ton verifying the environmental benefits of integrated HCPV-ETC arrangements in Kuwait.展开更多
As part of a broad strategy to reach net-zero greenhouse gas emissions and limit global warming,many countries are requiring all new buildings to have net-zero energy use.This requires that on-site energy use not exce...As part of a broad strategy to reach net-zero greenhouse gas emissions and limit global warming,many countries are requiring all new buildings to have net-zero energy use.This requires that on-site energy use not exceed on-site generation of renewable energy(taken here to be solar energy),or equivalently,that the building Energy Use Intensity(EUI,kWh/m^(2)a)not exceed the supply of on-site solar energy(electricity and heat)per m^(2)of floor area per year.On this basis,we find that achieving net-zero energy performance in an archetype 40-story square building in 16 different cities of North America requires EUI of 17–24 kWh/m^(2)a using PV panels,and 19–28 kWh/m^(2)a using PVT collectors.Changing building orientation to a non-square floor shape can improve maximum permitted EUI by up to 50%in PV and 60%in PVT case.Conversely,the best-performing residential and commercial buildings have EUIs of 50–75 kWh/m^(2)a.Only if building heights are limited to 5–10 floors does the available solar energy,and thus the permitted EUI,reach 50–75 kWh/m^(2)a.Therefore,we recommend that policymakers not require high-rise buildings to be net-zero energy,unless they are prepared to limit building heights to 5–10 floors.展开更多
Energy efficiency improvement in Chinese construction has progressed rapidly over the past two decades.Nearly zero energy buildings(NZEBs),as an integrated solution for energy-efficient construction,have gained signif...Energy efficiency improvement in Chinese construction has progressed rapidly over the past two decades.Nearly zero energy buildings(NZEBs),as an integrated solution for energy-efficient construction,have gained significant attention during China's 13th Five-Year Plan period,with continuous maturation of the technical system.In this study,a research framework built upon the accomplishments of China's National Key Research and Development Program is developed,and an in-depth analysis of the most cutting-edge research is provided by thoroughly reviewing the work conducted earlier.Developing NZEB in China has been categorized into three stages based on the characteristics of technological development:(1)definition and standards,(2)demonstration and promotion,and(3)cross-domain integration.This study discerns four noteworthy development trends by examining comprehensive data spanning the last decade from 100 NZEB and zero energy building.Further,a comprehensive analysis of essential technology advancements in line with these identified trends is performed.The issues and challenges arising from the increased application of renewable energy in the context of China's carbon peak and carbon neutrality goals have also been discussed.Finally,based on this analysis,the challenges and corresponding suggestions for future research directions were proposed to help guide future studies exploring emerging trends in the NZEB field.展开更多
To realize the goal of net zero energy building(NZEB),the integration of renewable energy and novel design of buildings is needed.The paths of energy demand reduction and additional energy supply with renewables are s...To realize the goal of net zero energy building(NZEB),the integration of renewable energy and novel design of buildings is needed.The paths of energy demand reduction and additional energy supply with renewables are separated.In this study,those two are merged into one integration.The concept is based on the combination of photovoltaic,thermoelectric modules,energy storage and control algorithms.Five types of building envelope systems,namely PV+TE(S1),Grid+TE(S2),PV+Grid+TE(S3),PV+Battery+TE(S4)and PV+Grid+Battery+TE(S5)are studied,from aspects of energy,economic and environmental(E3)performance.The new envelope systems can achieve thermal load reduction while providing additional cooling/heating supply,which can promote advance of NZEBs.It is found that there is a typical optimum setting of thermal energy load for each one of them with minimum annual power consumption.Except for the S1 system,the rest can realize negative accumulated power consumption in a year-round operation,which means the thermal load of building envelope could be zero.The uniform annual cost for S1 to S5 under interest rate of 0.04 are 19.78,14.77,23.83,60.53,64.94$/m2,respectively.The S5 system has the highest environmental effect with 3.04 t/m2 reduction of CO_(2) over 30 years of operation.展开更多
One of the challenges in construction of nearly and net ZEBs is how to truly achieve the nearly and net energy goals after building occupancy.Traditional building design standards and practices are mostly based on des...One of the challenges in construction of nearly and net ZEBs is how to truly achieve the nearly and net energy goals after building occupancy.Traditional building design standards and practices are mostly based on design performance evaluation,but practices show that many designed nearly/net ZEBs failed to achieve the energy goals after building occupancy.To facilitate the practical achievement of nearly and net ZEBs,recently most of the newly-released ZEB design standards have turned to post-occupancy performance evaluation,posing great challenges to nearly and net ZEB design.However,the detailed challenges have not be comprehensively investigated,and effective optimal design methods which can facilitate the achievement of nearly and net ZEBs under these standards are still absent.In this study,new challenges of nearly and net ZEB design under the post-occupancy performance-based design standards are fully investigated,and a risk-benefit based optimal design method is proposed to facilitate the achievement of nearly and net ZEBs under these standards.The newly-released ZEB standard in China is taken as an example to investigate the challenges and test the proposed method.Results show that nearly and net ZEBs designed using conventional design method have high risk in achieving energy goals under these standards due to high risk in satisfying the requirement regarding non-renewable primary energy consumption after building occupancy.The proposed design method is effective to facilitate achieving energy goals under these standards based on the risk that decision-makers would like to take.展开更多
The first available label standardizing a zero-balanced type of building is the Swiss Standard Minergie-A. The standard prescribes an annual net zero primary energy balance for heating, domestic hot water and ventilat...The first available label standardizing a zero-balanced type of building is the Swiss Standard Minergie-A. The standard prescribes an annual net zero primary energy balance for heating, domestic hot water and ventilation. Electricity consumption for appliances and lighting is excluded. Additionally, Minergie-A is the first standard worldwide which includes a requirement in regard to embodied energy. Based on an analysis of 39 Minergie-A buildings, this paper shows that a wide range of different energy concepts and embodied energy strategies are possible in the scope of the label. The basis of all Minergie-A buildings is a well-insulated building envelope. However, the step from the Swiss Standard Minergie-A to a Net ZEB (net zero energy building) standard which includes electricity consumption for appliances and lighting is not a very big one. Increasing the size of the photovoltaic system is sufficient in most cases. Anyway, some of the Minergie-A buildings evaluated are also Net ZEBs. In this paper, it is also shown that the net zero balance during the operational phase of Net ZEBs clearly outweighs the increased embodied energy for additional materials in a life cycle energy analysis.展开更多
文摘In the United States, university buildings use 17% of total non-residential building energy per year. According to the NREL (National Renewable Energy Laboratory), the average lifecycle of a building in a university is 42 years with an EUI (energy use intensity) of 23 kWh/m^2/y. Current building and energy codes limit the EUI to 16 kWh/m^2/y for new school buildings; this benchmark can vary depending on climate, occupancy, and other contextual factors. Although the LEED (leadership in energy and environmental design) system provides a set of guidelines to rate sustainable buildings, studies have shown that 28%-35% of the educational LEED-rated buildings use more energy than their conventional counterparts. This paper examines the issues specific to a LEED-rated design addition to an existing university building. The forum, a lecture hall expansion of to an existing building at the University of Kansas, has been proposed as environmentally friendly and energy-efficient building addition. Comfort and health aspects have been considered in the design in order to obtain LEED platinum certificate. The forum's energy performance strategies include a double-skin facade to reduce energy consumption and PV (photovoltaic) panels to generate onsite energy. This study considers various scenarios to meet NZEB (net-zero energy building) criteria and maximize energy savings. The feasibility of NZE criteria is evaluated for: (a) seasonal comparison; (b) facility occupancy; (c) PV panels' addition in relation to double skin facade. The results of NZEB approach are compared to LEED platinum requirements, based on Rol (return on investment) and PV panel's efficiency for this specific educational building.
文摘Net-zero energy buildings and communities, which are receiving increasing interest, and the role of energy storage in them, are described. A net-zero energy building or community is defined as one that, in an average year, produces as much energy from renewable energy as it consumes. Net-zero energy buildings and communities and the manner in which energy sustainability is facilitated by them are described and examples are given. Also, energy storage is discussed and the role and importance of energy storage as part of net-zero buildings and communities are explained. The NSERC Smart Net-zero Energy Buildings Research Network, a major Canadian research effort in smart net-zero energy buildings and communities, is described.
文摘In recent years,large high efficiency and Net-Zero Energy Buildings(NZEB)are becoming a reality that are setting construction and energy benchmarks for the industry.As part of this significant effort,in 2018,Mohawk College opened the 8,981 m^(2)(96,670 ft2)Joyce Centre for Partnership and Innovation(JCPI)building in Hamilton,Ontario;becoming Canada’s largest NZEB and zero-carbon institutional facility.The building integrated a high-efficiency design,construction materials,and technologies;as well as renewable energy technologies to significantly reduce its annual energy consumption and greenhouse gas emissions.Furthermore,the JCPI building was also designed as a living lab where students,faculty,researchers and industry are able to monitor and validate the performance of this state-of-the-art facility.The building was designed to have an energy use intensity of 73 kWh/m^(2)·year(0.26 GJ/m^(2)·year);hence,potentially consuming approximately 80%less energy than the average educational service building in Ontario.This paper gives an overview of the design criteria and technologies that were considered to achieve this innova-tive building.
文摘INTRODUCTION The level of man-made CO_(2) emissions worldwide climbed to a new record of 30 billion tons in 2010.In 2011,at the COP17 U.N.Climate Change Conference in Durban,South Africa,high-ranking representatives from around the world met again to discuss solutions.For the building sector,numerous energy-efficiency market changes and benchmarking resolutions,like the mandatory E.U.“nearly Net-Zero-Energy-Building(NET-ZEB’s)2018 and 2020 regulations”for all new public and privately owned buildings are now set up to help minimizing carbon emissions and reverse the negative impact.1 In the United States,the American Institute of Architects(AIA)adopted the 2030 Challenge as a voluntary program,where participating buildings aim to achieve a 90%fossil fuel reduction by 2025,and carbon-neutrality by 2030.2 To accomplish these energy goals,designers must strive to best design and utilize the resources available on a site.However,are these goals of achieving carbon-neutral buildings possible?How can NET-ZEB’s become the curricular standard and practical routine in education and the profession?To date,the basic curricular design process components with integrated project delivery metrics for a robust 3-D/4-D-net-zero regulatory design framework are either incomplete or missing,However,formally-based curriculums have begun to weave carbon-neutral design tools into their pedagogy.This research paper critically compares how these new criteria for digital 3-D-building information modeling(BIM),and“Integrated Project Delivery”are mandating a better integration of collaborative carbon-neutral designs into the curriculum and practice of the profession.The majority of those in architectural academia have been using generative computation primarily for pure,aesthetic form-finding,without applying zero-carbon-energy-driven global performance metrics and CO_(2)e reduction strategies to reiterate derived carbon-neutral designs.The advantage of 3-D-parametric design is that it links variables,dimensions,and materials to geometry in a way that when an input or simulation value changes,the 3-D/4-D model automatically updates all life-cycle scenarios and components simultaneously.
文摘Near-zero energy buildings( nZEBs) are considered as an effective solution to mitigating CO_2 emissions and reducing the energy usage in the building sector. A proper sizing of the nZEB systems( e. g. HVAC systems,energy supply systems,energy storage systems, etc.) is essential for achieving the desired annual energy balance,thermal comfort,and grid independence. Two significant factors affecting the sizing of nZEB systems are the uncertainties confronted by the building usage condition and weather condition,and the degradation effects in nZEB system components. The former factor has been studied by many researchers; however,the impact of degradation is still neglected in most studies. Degradation is prevalent in energy components of nZEB and inevitably leads to the deterioration of nZEB life-cycle performance. As a result,neglecting the degradation effects may lead to a system design which can only achieve the desired performance at the beginning several years. This paper,therefore,proposes a life-cycle performance analysis( LCPA) method for investigating the impact of degradation on the longitudinal performance of the nZEBs. The method not only integrates the uncertainties in predicting building thermal load and weather condition,but also considers the degradation in the nZEB systems. Based on the proposed LCPA method,a two-stage method is proposed to improve the sizing of the nZEB systems.The study can improve the designers "understanding of the components"degradation impacts and the proposed method is effective in the life-cycle performance analysis and improvements of nZEBs. It is the first time that the impacts of degradation and uncertainties on nZEB LCP are analysed. Case studies showthat an nZEB might not fulfil its definition at all after some years due to component degradation,while the proposed two-stage design method can effectively alleviate this problem.
文摘Conferences and publications on Smart Cities and self-styled ecological buildings such as“Vertical Forests”,“Biophilic”building complexes and other similar are multiplying.But then,in reality,we continue to design as we have always done for the last ninety years:with the consolidated rules and formal solutions of international post-modern composition,in its various forms.The only attentions are(and not always)to super-insulate the envelopes,arrange photovoltaic panels on the roofs,make the systems smart and cover the facades and roofs with appropriate green washing.Even in the awareness that human settlements and cities are extremely complex phenomena,mostly determined by economic and social factors,rather than by conscious typological-settlement choices,perhaps the time has come to acknowledge that the traditional paradigms of design must be changed.First of all,the types of settlements must be renewed,because it is through their optimization that the greatest savings in terms of energy and sustainability can be achieved.The research presented here is the application of a ten-year study that involved the development of net Zero Energy Mass Custom Housing(ZEMCH)in specific context in southern Italy.The Innovation and Transparency of Tenders Environmental Compatibility(ITACA)Assessment Protocol,derived from the Green Building Challenge’s GBTool,was used as a design guide,which is normally used for the assessment and judgment of sustainability at the building scale and not of the urban design.The result is a settlement model in which network of pedestrian,cycle and public transport is fully integrated with adjacent urban areas;effective landscaping connects public and private green and kitchen-gardens/orchards everywhere;buildings are made with new semi-underground typologies;net ZEMCHs are made with local,recyclable materials with low impact or positive energy balance;wastewater and rainwater are collected,in-loco phyto-purified and reused;renewable energies(sun,earth,wind)satisfy remaining necessities,with a minimum of plant interventions.
基金Sponsored by the National Natural Science Foundation of China(Grant No.71271180,71271065,71390522)the Program for New Century Excellent Talents in University(Grant No.NCET-11-0811)
文摘This paper presents a simulation technology of environmental impact for the building. By emergy analysis method,emergy costs of building( or construction engineering) can be calculated in the life cycle. It includes the engineering cost, environmental cost and social cost of building. Through integrating GIS technology with multi-agent technology,life cycle substance and energy metabolism of building( construction engineering) can be simulated and their environmental influence can be dynamically displayed. Based on the case study of entries works‘Sunny Inside'by Xiamen University in 2013 China International Solar Decathlon Competition,we discovered the changing pattern of surrounding environmental impact from waste streams of the zero-energy building and ordinary construction. The simulation results verified and showed the Odum principles of maximum power. This paper provides a new research perspective and integration approach for the environmental impact assessment in building and construction engineering. The result will help decision-making in design and construction engineering scheme.
文摘Decrease of energy consumption in buildings and increase of the share of renewable energies in them are currently technologically and economically feasible and it is promoted by E.U. policies. After 2019, all the new public buildings in EU countries must be near zero energy buildings reducing their energy consumption and CO<sub>2</sub> emissions. Use of various renewable energies for heat and power generation in school buildings in Crete-Greece can result in zeroing their fossil fuels consumption and CO<sub>2</sub> emissions. Purpose of the current work is to investigate the possibilities of creating zero CO<sub>2</sub> emissions school buildings in Crete-Greece due to operational energy use in them. A methodology which allows the replacement of fossil fuels with renewable energies in school buildings is proposed. Solar energy, solid biomass and low enthalpy geothermal energy, which are abundant in Crete, can be used for that. School buildings in Greece consume significantly less energy, 68 KWh/m<sup>2</sup> year, and emit less CO<sub>2</sub>, 28 kgCO<sub>2</sub>/m<sup>2</sup> year, than the corresponding buildings in other countries. The installation cost of renewable energies systems in order to replace all fossil fuels used in school buildings in Crete-Greece and to zero their CO<sub>2</sub> consumption due to energy use in them has been estimated at 47.42 - 87.71 €/m<sup>2</sup>, which corresponds to 1.69 - 3.13 €/kg CO<sub>2</sub> saved.
基金The research presented in this paper is a part of the research and demonstration project FP7 EE-Highrise—Energy efficient demo multi-residential high-rise building supported by the European Commission within the 7th Framework Programme(FP7-2011-NMP-ENV-ENERGY-ICT-EEB)(2013-2015)(www.ee-highrise.eu).
文摘Nearly zero energy buildings (nZEB) will become an obligatory energy efficiency standard in Europe. Following to common guidelines in European legislation, the countries investigated technical and economic framework for the preparation of detailed national technical definition of nZEB. Slovenia accepted the nZEB criteria in early 2015. This paper describes the technical and economic background for identification of economically viable concepts of highly energy efficient apartment building. The highrise demonstration building Eco Silver House revealed that meeting nZEB standards was not an easy task, not so much for technical reasons, but mostly due to the processes, inadequate skills, not fully compliant regulation and insufficient possibilities for interaction between the building and energy networks. Analysis of cost effectiveness showed that the Eco Silver House fulfilled minimal requirements of cost-optimal for apartment building with Net Present Value of 272 EUR/m2 and Primary energy use of 79 kWh/ m2?a in line with the Slovenian national cost optimal study of minimum energy performance requirements from the year 2014. At the time, the requirement of 50% share of renewables in final energy use is not fulfilled, but will be easily reached when EU2020 energy efficiency targets set in the Slovenian Energy Act regarding the RES share in district heating systems and public power grid will be gradually implemented. The demonstration project FP7 EE-HIGHRISE confirms that in spite of the barriers, the nZEB minimum requirements defined on profound theoretical studies can be met in practice.
文摘INTRODUCTION Recent development has seen a drastic increase in energy use trends in Saudi Arabian buildings leading to a demand for an effective course of action for energy conservation and production.A case study-based research initiative explor-ing near-zero energy potential in Saudi Arabia was undertaken.A 4-bedroom detached single-family faculty residence at King Fahd University of Petroleum and Minerals(KFUPM)representing common regional housing design trends was utilized.A base case simulation model of the house was developed and val-idated using short-term and real-time energy consumption data.Three sets of strategies:passive design strategies,representative codes and standards,and renewable technology were employed in the new design of the house.Passive strategies com-prised a green roof,a ventilated wall system,a sloped roof,and insulation for thermal bridges.These alternatives helped reduce the annual energy consumption of the house by 17.2%.The most recent version of the International Energy Conserva-tion Code(IECC 2012)was also incorporated along with ASHRAE Standard 62.2 for ventilation.The code and standard together reduced the annual energy consumption by 31.1%.Solar PV was then utilized to reduce grid utilization for the remainder of the house energy loads.This strategy provided 24.7%of the total energy consumed annually.A combination of strategies showed a 70.7%energy consumption reduction,thereby decreasing the energy index of the house from 162.9 to 47.7 kWh/m^(2)/yr.The Zero Energy Building(ZEB)concepts and strategies utilized in this study demonstrate a socially responsible approach to achieving near-zero energy performance for an existing house.
文摘The goal of this work is to evaluate and to give evidence to innovative and sustainable technologies applied in the construction industry to carry out self-sufficient energy and to use the surplus energy for the production of hydrogen vector. An architectural integration design along with high technological systems is performed. The intermittency of renewable energy sources along with climatic conditions dependency imposes to store the energy produced, since it is clean and having a big calorific value: the hydrogen vector is currently the better energy carrier. The energy to obtain hydrogen by dissociation of water is supplied by a photovoltaic (PV) system. Through the computations of the annual energy balance between building’s demand and supply energy, it is shown that the extra energy produced by the solar generation system is used also for the hydrogen sustainable mobility. The renewable systems, model’s design and case study are tackled for the bigger one of the Dodecanese islands in the South Aegean Sea: Rhodes (Rodos). The Zero energy building’s integrative design-based approach, applied to the Hotel Buildings type industry is targeted to have new hotels buildings, in the Mediterranean typical warm climate, with zero energy consumption. The designers, authors of this work, have studied a real case or pilot project of an hotel, in the resort formula, suitable to the Greek landscape, showcasing technologies and innovations supporting environmental sustainability, energy efficiency, use of renewable energy, electricity storage by fuel cells that are tools particularly applicable to hotel facility [1]. The feasibility of this case study or pilot project is aligned jointly to the target of Zero Emission and Energy Efficiency EU Policy, as imposed by EU Directives. The strategic position of Rhodes in a geographical point full of sun and wind renewable energy power, enables to ensure the clean energy production, the current interesting development of the hydrogen as energy vector in the buildings [2] and also to satisfy the demand of tourists’ accommodation by having at the same time zero energy costs. Moreover, the presence in the island of the best example worldwide of ancient and sustainable built environment (UNESCO World Heritage site), represents also the best motivation to give witness there of a zero impact environmental urban development through the adoption of these achieved scientific results for a major success of Zero Energy Buildings.
基金supported by a study funded from the General Research Fund of Hong Kong Research Grants Council (17207115).
文摘Buildings contribute around 45%of the world’s energy consumption.Reducing energy demand in buildings therefore plays a vital role in addressing the depletion of energy resources and associated environmental issues.Previous research explored the optimisations of the costs and energy consumption of buildings,but often overlooked the connections,tradeoffs and synergies between them.The aim of this paper is thus to develop a theoretical model of the influencing parameters of the life cycle cost-energy relationship(LCCER)of buildings using the Political,Economic,Sociocultural,Technological,Environmental and Legal(PESTEL)analytical framework.is study was carried out through a critical literature review,model development and validation through case studies with four zero or nearly zero energy building projects carefully selected from the European Union and Australia.The developed model addresses the buildings’LCCER by identifying the key influencing parameters and explicating the mechanisms(namely,the simultaneous and unilateral effects)by which the identified parameters affect such relationship.The important influencing parameters were found to reside in two aspects:(1)internal project designs covering building characteristics,building structure and function,and construction process,and(2)external environments covering climate,economic condition,occupant behaviour,policy and regulation,and buildings’lifespan focused in the studies.Various statistical correlations were found to exist between the costs and energy consumption of the studied cases.It is summarised that these correlations may be attributable to the synergy between the simultaneous and unilateral effects of the identified parameters.The developed model contributes a systemic approach to examining the building’s life cycle economics and energy in a comparative manner.
文摘The Centre of Excellence at Okanagan College in Penticton,British Columbia is being designed as one of the most innovative and sustainable post-secondary facilities in the world.On schedule for design and construction to be complete by April 2011,the two-storey multi-purpose facility has a mandate to provide trades and technology training and professional development to students from the province of British Columbia and beyond.It is aimed at attaining the highest standard of sustainable building design,the Living Building Challenge.The building will support a syllabus with a focus on the design,installation,and support of sustainable building technologies and processes,and the development and application of alternative and renewable energy.The building itself will become an essential element of the educational programs that will reside there,a teaching tool for education on building trades and engineering technologies.In addition,the Okanagan Research Innovation Centre will be incorporated into the building,providing opportunities for start-up companies to develop and prototype new green technologies in a supportive and synergistic environment.This article will demonstrate that a project with this level of sustainable objectives is achievable at a cost comparable to conventional building design.It will address how this can be attained through an integrated design process,along with the numerous innovative features that have been incorporated into the building design to help it function with a small environmental impact,and a large educational one.
文摘Energy consumption in buildings is considered a significant portion of gross power dissipation, so a great effort is required to design efficient construction. In severe hot weather conditions as Kuwait, energy required for building cooling and heating results in a huge energy loads and consumption and accordingly high emission rates of carbon dioxide. So, the main purpose of the current work is to convert the existing institutional building to near net-zero energy building (nNZEB) or into a net-zero energy building (NZEB). A combination of integrated high concentrated photovoltaic (HCPV) solar modules and evacuated tube collectors (ETC) are proposed to provide domestic water heating, electricity load as well as cooling consumption of an institutional facility. An equivalent circuit model for single diode is implemented to evaluate triple junction HCPV modules efficiency considering concentration level and temperature effects. A code compatible with TRNSYS subroutines is introduced to optimize evacuated tube collector efficiency. The developed models are validated through comparison with experimental data available from literature. The efficiency of integrated HCPV-ETC unit is optimized by varying the different system parameters. Transient simulation program (TRNSYS) is adapted to determine the performance of various parts of HCPV-ETC system. Furthermore, a theoretical code is introduced to evaluate the environmental effects of the proposed building when integrated with renewable energy systems. The integrated HCPV-ETC fully satisfies the energy required for building lighting and equipment. Utilizing HCPV modules of orientation 25? accomplishes a minimum energy payback time of about 8 years. Integrated solar absorption chiller provides about 64% of the annual air conditioning consumption needed for the studied building. The energy payback period (EPT) or solar cooling system is about 18 years which is significantly larger than that corresponding to HCPV due to the extra expenses of solar absorption system. The life cycle savings (LCS) of solar cooling absorption system is approximately $2400/year. Furthermore, levelized cost of energy of solar absorption cooling is $0.21/kWh. Hence, the net cost of the solar system after subtracting the CO2 emission cost will be close to the present price of conventional generation in Kuwait (about $0.17/kWh). Finally, the yearly CO2 emission avoided is approximately 543 ton verifying the environmental benefits of integrated HCPV-ETC arrangements in Kuwait.
文摘As part of a broad strategy to reach net-zero greenhouse gas emissions and limit global warming,many countries are requiring all new buildings to have net-zero energy use.This requires that on-site energy use not exceed on-site generation of renewable energy(taken here to be solar energy),or equivalently,that the building Energy Use Intensity(EUI,kWh/m^(2)a)not exceed the supply of on-site solar energy(electricity and heat)per m^(2)of floor area per year.On this basis,we find that achieving net-zero energy performance in an archetype 40-story square building in 16 different cities of North America requires EUI of 17–24 kWh/m^(2)a using PV panels,and 19–28 kWh/m^(2)a using PVT collectors.Changing building orientation to a non-square floor shape can improve maximum permitted EUI by up to 50%in PV and 60%in PVT case.Conversely,the best-performing residential and commercial buildings have EUIs of 50–75 kWh/m^(2)a.Only if building heights are limited to 5–10 floors does the available solar energy,and thus the permitted EUI,reach 50–75 kWh/m^(2)a.Therefore,we recommend that policymakers not require high-rise buildings to be net-zero energy,unless they are prepared to limit building heights to 5–10 floors.
基金supported by the National Key Research and Development Program of China(Grant No.2022YFC3803300)。
文摘Energy efficiency improvement in Chinese construction has progressed rapidly over the past two decades.Nearly zero energy buildings(NZEBs),as an integrated solution for energy-efficient construction,have gained significant attention during China's 13th Five-Year Plan period,with continuous maturation of the technical system.In this study,a research framework built upon the accomplishments of China's National Key Research and Development Program is developed,and an in-depth analysis of the most cutting-edge research is provided by thoroughly reviewing the work conducted earlier.Developing NZEB in China has been categorized into three stages based on the characteristics of technological development:(1)definition and standards,(2)demonstration and promotion,and(3)cross-domain integration.This study discerns four noteworthy development trends by examining comprehensive data spanning the last decade from 100 NZEB and zero energy building.Further,a comprehensive analysis of essential technology advancements in line with these identified trends is performed.The issues and challenges arising from the increased application of renewable energy in the context of China's carbon peak and carbon neutrality goals have also been discussed.Finally,based on this analysis,the challenges and corresponding suggestions for future research directions were proposed to help guide future studies exploring emerging trends in the NZEB field.
基金supported by the National Key R&D Program of China(No.2019YFE0193100,No.2021YFE0113500)the Fundamental Research Funds for the Central Universities,China(No.2019kfyXJJS189,No.2020kfyXJJS097)Research Project of the Ministry of Housing and Urban-Rural Development of China“Research and Demonstration of Optimal Configuration of Energy Storage System in Nearly Zero Energy Communities”(K20210466).
文摘To realize the goal of net zero energy building(NZEB),the integration of renewable energy and novel design of buildings is needed.The paths of energy demand reduction and additional energy supply with renewables are separated.In this study,those two are merged into one integration.The concept is based on the combination of photovoltaic,thermoelectric modules,energy storage and control algorithms.Five types of building envelope systems,namely PV+TE(S1),Grid+TE(S2),PV+Grid+TE(S3),PV+Battery+TE(S4)and PV+Grid+Battery+TE(S5)are studied,from aspects of energy,economic and environmental(E3)performance.The new envelope systems can achieve thermal load reduction while providing additional cooling/heating supply,which can promote advance of NZEBs.It is found that there is a typical optimum setting of thermal energy load for each one of them with minimum annual power consumption.Except for the S1 system,the rest can realize negative accumulated power consumption in a year-round operation,which means the thermal load of building envelope could be zero.The uniform annual cost for S1 to S5 under interest rate of 0.04 are 19.78,14.77,23.83,60.53,64.94$/m2,respectively.The S5 system has the highest environmental effect with 3.04 t/m2 reduction of CO_(2) over 30 years of operation.
基金supported by a grant(152079/18E)from the Research Grant Council(RGC)of the Hong Kong SAR,China.
文摘One of the challenges in construction of nearly and net ZEBs is how to truly achieve the nearly and net energy goals after building occupancy.Traditional building design standards and practices are mostly based on design performance evaluation,but practices show that many designed nearly/net ZEBs failed to achieve the energy goals after building occupancy.To facilitate the practical achievement of nearly and net ZEBs,recently most of the newly-released ZEB design standards have turned to post-occupancy performance evaluation,posing great challenges to nearly and net ZEB design.However,the detailed challenges have not be comprehensively investigated,and effective optimal design methods which can facilitate the achievement of nearly and net ZEBs under these standards are still absent.In this study,new challenges of nearly and net ZEB design under the post-occupancy performance-based design standards are fully investigated,and a risk-benefit based optimal design method is proposed to facilitate the achievement of nearly and net ZEBs under these standards.The newly-released ZEB standard in China is taken as an example to investigate the challenges and test the proposed method.Results show that nearly and net ZEBs designed using conventional design method have high risk in achieving energy goals under these standards due to high risk in satisfying the requirement regarding non-renewable primary energy consumption after building occupancy.The proposed design method is effective to facilitate achieving energy goals under these standards based on the risk that decision-makers would like to take.
文摘The first available label standardizing a zero-balanced type of building is the Swiss Standard Minergie-A. The standard prescribes an annual net zero primary energy balance for heating, domestic hot water and ventilation. Electricity consumption for appliances and lighting is excluded. Additionally, Minergie-A is the first standard worldwide which includes a requirement in regard to embodied energy. Based on an analysis of 39 Minergie-A buildings, this paper shows that a wide range of different energy concepts and embodied energy strategies are possible in the scope of the label. The basis of all Minergie-A buildings is a well-insulated building envelope. However, the step from the Swiss Standard Minergie-A to a Net ZEB (net zero energy building) standard which includes electricity consumption for appliances and lighting is not a very big one. Increasing the size of the photovoltaic system is sufficient in most cases. Anyway, some of the Minergie-A buildings evaluated are also Net ZEBs. In this paper, it is also shown that the net zero balance during the operational phase of Net ZEBs clearly outweighs the increased embodied energy for additional materials in a life cycle energy analysis.