Carbon Footprint Analysis of Buildings Based on LCA Theory Under Carbon Neutrality Goals:Taking the 3rd China International Solar Decathlon Competition as an Example

This paper focuses on the design of residential buildings oriented to the efficient use of solar energy,and selects the entries HUI HOUSE of Hefei University of Technology and Lille I University of France in the 3rd China International Solar Decathlon China Competition,based on the theory of the life cycle assessment(LCA)of buildings,and analyzes the carbon footprint from four aspects:building materials production and transportation stage,building construction stage,building operation stage,and building demolition stage.Through the calculation of the carbon footprint of buildings,the socio-economic benefits of HUI HOUSE in carbon reduction were analyzed;the result of the calculation was that HUI HOUSE achieved carbon neutrality in the ninth year,and continued carbon reduction after that,contributing a cumulative total of 947.54 tons of carbon negative in the life cycle of buildings.

Simulation Technology of Environmental Impacts by Zero-energy Residential Buildings Based on Emergy Analysis Method

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.

The Thermal Comfort and Hygrothermal Performance of the First Certified Passive House in Estonia

This study presents the thermal comfort and hygrothermal performance of building envelope of the first certified passive single-family detached house in Estonia.Temperature and humidity conditions were measured from different rooms and building envelopes.This article presents analysis of measurement results during the first year after construction.Results showed high room temperature,achieved mainly due to large windows with southern exposure and the small heat loss of the building envelope.High indoor temperature decreased the indoor RH(relative humidity)to quite low levels.Even the RH was low,the moisture excess was high indicating that the design of PH(passive houses)indoor humidity loads cannot be decreased.Humidity in the externally insulated cross-laminated timber panels was observed to be high,caused by drying out of the constructional moisture and the high diffusion resistance of the wood fibre sheathing board.That caused water vapour condensation and risk for mould growth.In conclusion,while planning buildings with high-energy efficiency,more focused attention should be paid to the performance of the building service systems and moisture safety already in the preliminary stages of design.

基于全寿命周期的寒冷地区零能耗公共建筑的经济效益分析

为实现我国双碳目标,本文从全寿命周期的角度对零能耗公共建筑的经济效益进行了分析。结合零能耗公共建筑的特点,从项目前期、施工阶段、使用阶段、报废回收阶段等四个阶段计算零能耗建筑的增量成本和经济效益。最后以中德展厅项目为例,实证分析寒冷地区零能耗公共建筑的经济效益和影响因素,为我国零能耗建筑的发展提供借鉴。

Comprehensive evaluation and analysis of a nearly zero-energy building heating system using a multi-source heat pump in severe cold region

The integrated application of multi-energy coupled technology in nearly zero-energy building(NZEB)is promising from the perspective of low-carbon development to achieve the goal of net zero energy.PVT(photovoltaic/thermal),air,and ground sources were combined organically to establish an experimental platform of a multi-source heat pump(MSHP)system,which can realize flexible switching of multi-energy sources.The paper presents the analytical hierarchy process and fuzzy comprehensive evaluation method to comprehensively evaluate the five modes of the MSHP system with regard to energy,economic and environmental benefits.The results indicate that the waste heat of the PVT cavity can improve the coefficient of performance of the heat pump unit(COP)by approximately 8.0%.The initial investment in air source heat pump(ASHP)modes is lower than that of a coal-powered system.The ground source heat pump(GSHP)modes have high stability and their payback period is 8.81–10.66 years.The photovoltaic/thermal-dual source heat pump(PVT-DSHP)mode presents the most appropriate system applied in the NZEB in severe cold region,followed by the DSHP,GSHP,ASHP,and PVT-ASHP mode.When compared with other modes,COP,annual saving cost,carbon dioxide emission reduction,and comprehensive value of the PVT-DSHP mode have improved by 7.07%–29.57%,2.21%–23.88%,3.38%–14.83%,and 27.91%–52.62%,respectively.The study provides important insights into the practical application and sustainable development of multi-energy coupled systems in the NZEB in severe cold region.

Analysis of the effect of passive measures on the energy consumption and zero-energy prospects of residential buildings in Pakistan

Climate change can adversely impact the thermal comfort and energy efficiency of the buildings stock. The South Asian countries are particularly vulnerable to the adverse impacts of climate change specially in the form of rising temperatures and increasing frequency of heat waves. The passive building design measures can be useful in mitigating and adapting to the climate change by increasing energy efficiency and reducing greenhouse gas (GHG) emissions. In this study various passive climate change adaptation measures (PCAMs) have been used individually and in form of combinations in order to analyze their impact on the energy efficacy of residential buildings in Pakistan. It has been found that the natural ventilation and front green wall are the most efficient options for reducing the overall energy consumption. By implementation of these PCAMs, cooling demand can be decreased by 27.75% while heating demand can be reduced by 35%. Secondly, the prospect of net zero-energy building and reduced CO2 emissions are also studied. It has been shown that building can achieve net-zero energy on an annual basis at every orientation and it can attain the status of nearly zero-energy building on a monthly basis. Moreover, emitted CO2 can be reduced by 31% by using the renewable energy.

分散天井在零耗能建筑中的应用

随着建筑节能技术的发展,近年来零耗能建筑的研究与实践已经在国内外展开。该文首先探讨了零耗能建筑的设计原理,其次通过分析传统民居案例来重点研究分散天井式建筑在自然采光、通风的生态作用下的能耗状态,说明分散天井式建筑是良好的环境响应型建筑。最后论文探索了以分散天井式建筑为原型,辅助以智能采光通风及太阳能发电等主被动节能技术,建立零耗能建筑设计模型的可能性。

New challenges for optimal design of nearly/net zero energy buildings under post-occupancy performance-based design standards and a risk-benefit based solution

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.

The Benefits of Integrated Methods in PV Making to Promote Their Efficiency and Achieve Low-Cost Modules

Active systems, such as solar thermal and photovoltaic offer a great potential in reducing of fuel energy consumption. To improve the sustainability of buildings, one of the challenges is to address the role of renewable energies. Today, the photovoltaic installations play an important role in creating solar renewable energy. They create 2000 MW electrical energy per year and its annual global sales grown to approximately 5.6 GWp. This paper presents a general overview on a serious effort to produce PV panels that could provide cheaper solar power. It also focuses on short background of PV. Furthermore, thin film technology benefits, the method of the most absorbing of solar spectrum and the method of solar concentration and the advantages of these systems are presented. Ultimately, a new high concentration PV power system will be assessed.

Zero Energy Hotels and Sustainable Mobility in the Islands of Aegean Sea (Greece)

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.

Modeling and management performances of distributed energy resource for demand flexibility in Japanese zero energy house

Zero-energy buildings(ZEBs)can contribute to decarbonizing building energy systems,while the energy mismatch between energy demand and on-site stochastic generation in ZEBs increases the need for energy flexibility.This study proposed mixed-integer linear programming energy management schemes for optimizing the flexible scheduling of distributed energy resources,including battery energy storage,heat pump,and building thermal mass as a passive thermal energy storage system.With optimally designed objectives,this study used case studies to evaluate the flexibility potential provided by the demand-side management,considering dynamic characteristics of the process.The results showed that the proposed demand-side management for battery storage offers significant potential in increasing photovoltaic(PV)self-consumption and reducing operational costs.Cost reduction ratios of flexible dispatch of combined PV and battery storage systems exceed 15%.Flexible coupling of PV and heat pump systems for meeting hot water demand can reduce energy cost by more than 20%.The flexible coupling of the heat pump and PV system also had a significant impact on the power consumption pattern of domestic heat pumps,the load-shifting potential highly depends on the available PV generation and hot water demand.The optimal trade-off between thermal energy use and thermal comfort violation may not reduce the total energy used for space heating,the increased PV consumption helped reduce grid imports.The study provides insights into the energy flexibility behavior and efficiency of the proposed demand-side management for ZEBs,which is expected to provide guidelines for exploring demand-side flexibility.