Estimation of Building’s Life Cycle Carbon Emissions Based on Life Cycle Assessment and Building Information Modeling: A Case Study of a Hospital Building in China

Throughout the life cycle, the buildings emit a great deal of carbon dioxide into the atmosphere, which directly leads to aggravation in the greenhouse effect and becomes a severe threat to the environment and humans. Researchers have made numerous efforts to accurately calculate emissions to reduce the life cycle carbon emissions of residential buildings. Nevertheless, there are still difficulties in quickly estimating carbon emissions in the design stage without specific data. To fill this gap, the study, based on Life Cycle Assessment (LCA) and Building Information Modeling (BIM), proposed a quick method for estimating Building’s Life Cycle Carbon Emissions (BLCCE). Taking a hospital building in Chuzhou City, Anhui Province, China as an example, it tested its possibility to estimate BLCCE. The results manifested that: 1) the BLCCE of the project is 40,083.56 tCO2-eq, and the carbon emissions per square meter per year are 119.91 kgCO2-eq/(m2·y);2) the stage of construction, operational and demolition account for 7.90%, 91.31%, and 0.79% of BLCCE, respectively;3) the annual carbon emissions per square meter of hospital are apparently higher than that of villa, residence, and office building, due to larger service population, longer daily operation time, and stricter patient comfort requirements. Considering the lack of BLCCE research in Chinese hospitals, this case study will provide a valuable reference for the estimated BLCCE of hospital building.

Carbon emissions reduction potentiality for railroad transportation based on life cycle assessment

This study addresses the comparative carbon emissions of different transportation modes within a unified evaluation framework,focusing on their carbon footprints from inception to disposal.Specifically,the entire life cycle carbon emissions of High-Speed Rail(HSR),battery electric vehicles,conventional internal combustion engine vehicles,battery electric buses,and conventional internal combustion engine buses are analyzed.The life cycle is segmented into vehicle manufacturing,fuel or electricity production,operational,and dismantlingrecycling stages.This analysis is applied to the Beijing-Tianjin intercity transportation system to explore emission reduction strategies.Results indicate that HSR demonstrates significant carbon emission reduction,with an intensity of only 24%-32% compared to private vehicles and 47%-89% compared to buses.Notably,HSR travel for Beijing-Tianjin intercity emits only 24% of private vehicle emissions,demonstrating the emission reduction benefits of transportation structure optimization.Additionally,predictive modeling reveals the potential for carbon emission reduction through energy structure optimization,providing a guideline for the development of effective transportation management systems.

Carbon footprint accounting for cigar production processes: A life cycle assessment perspective

Although the tobacco industry is a significant contributor to energy consumption and carbon emissions its negative environmental impact has received inadequate attention globally.Cigarette factories are a key link in the tobacco industry’s production chain,and using data provided by a cigarette factory in China we conduct a life cycle assessment to account for the carbon footprint of cigar production in cigarette factories.The results of the assessment show that factory air conditioning is the most important contributor to the environmental load of the cigar manufacturing process,while electricity is the key factor that contributes the greatest envi‐ronmental load across all of the processes in the product life cycle.In addition,packaging,including small boxes and cigarette cartons,has a significant impact on the industry’s environmental footprint due to its use of raw materials.We find the carbon footprint of the entire production process for cigar products to be 383.59 kg CO_(2) eq.Based on our findings,we suggest ways to optimize cigar/cigarette factory processes to re‐duce carbon emissions that can help to promote sustainable development in related industries.

Carbon emission analysis of a residential building in China through life cycle assessment

In this paper, a quantitative life cycle model for carbon emission accounting was developed based on the life cycle assessment （LCA） theory. A residential building in Sino-Singapore Tianjin Eco-city （Tianjin, China） was selected as a sample, which had been constructed according to the concept of green environmental protection and sustainable development. In the scenario of this research, material production, construction, use and maintenance, and demolition phases were assessed by building carbon emission models. Results show that use and maintenance phase and material production phase are the most significant contributors to the life cycle carbon emissions of a building. We also analyzed some factor influences in LCA, including the thickness of the insulating layer and the length of building service life. The analysis suggest that thicker insulating layer does not necessarily produce less carbon emissions in the light of LCA, and if service life of a building increases, its carbon emissions during the whole life cycle will rise as well but its unit carbon emission will decrease inversely. Some advices on controlling carbon emissions from buildings are also provided.

Life cycle carbon emission assessment of a multi-purpose university building:A case study of Sri Lanka

Buildings are known to significantly affect the global carbon emissions throughout their life cycle. To mitigate carbon emissions, investigation of the current performance of buildings with regard to energy consumption and carbon emissions is necessary. This paper presents a process-based life cycle assessment methodology for assessing carbon emissions of buildings, using a multistorey reinforced concrete building in a Sri Lankan university as a case study. The entire cradle-to-grave building life cycle was assessed and the life span of the building was assumed as 50 years. The results provide evidence of the significance of operation and material production stages, which contributed to the total carbon emissions by 63.22% and 31.59% respectively. Between them, the main structural materials, concrete and reinforcement steel made up 61.91% of the total carbon emitted at the material production stage. The life cycle carbon emissions of the building were found to be 31.81 kg·m^(–2) CO_2 per year, which is comparable with the values obtained in similar studies found in the literature. In minimizing the life cycle carbon emissions, the importance of identifying control measures for both building operation and material production at the early design stage were emphasized. Although the other life cycle stages only contributed to about 5.19% of the life cycle carbon emissions, they should also receive attention when formulating control strategies. Some of the recommended strategies are introducing energy efficiency measures in building design and operation, using renewable energy for building operation and manufacturing of materials,identifying designs that can save mass material quantities,using alternative materials that are locally available in Sri Lanka and implementing material reuse and recycling.This study is one of the first to undertake a life cycle carbon emissions assessment for a building in the Sri Lankan context, with the hope of facilitating environmentallyfriendly buildings and promoting sustainable construction practices in the country.

Greenhouse gas emission analysis and measurement for urban rail transit: A review of research progress and prospects

Rail transit plays a key role in mitigating transportation system carbon emissions.Accurate measurement of urban rail transit carbon emission can help quantify the contribution of urban rail transit towards urban transportation carbon emission reduction.Since the whole life cycle of urban rail transit carbon emission measurement involves a wide range of aspects,a systematic framework model is required for analysis.This research reviews the existing studies on carbon emission of urban rail transit.First,the characteristics of urban rail transit carbon emission were determined and the complexity of carbon emission measurement was analyzed.Then,the urban rail transit carbon emission measurement models were compared and analyzed in terms of the selection of research boundaries,the types of greenhouse gas(GHG)emissions calculation,and the accuracy of the measurement.Following that,an intelligent station was introduced to analyze the practical application of digital collaboration technology and energy-saving and carbon-reducing system platforms for rail transit.Finally,the urgent problems and future research directions at this stage were discussed.This research presents the necessity of establishing a dynamic carbon emission factor library and the important development trend of system integration of carbon emission measurement and digital system technology.

Life cycle assessment on the environmental impacts of different pig manure management techniques

The management of livestock waste is an effective way to achieve emission reduction and carbon fixation in agriculture and rural areas.At present,aerobic composting and anaerobic fermentation are widely used in livestock waste treatment technology.In this study,pig manure management was taken as an example,a comprehensive environmental load index was constructed to quantitatively evaluate the environmental impacts of global warming,environmental acidification,eutrophication,and photochemical ozone synthesis during aerobic composting and anaerobic fermentation based on the life cycle assessment.The results showed that the potential values of aerobic composting and anaerobic fermentation were similar,and the order was global warming,environmental acidification,eutrophication,and photochemical ozone synthesis.Anaerobic fermentation contributed more to global warming,while aerobic composting contributed more to environmental acidification,eutrophication,and photochemical ozone synthesis.In addition,the environmental load index of aerobic composting was significantly higher than that of anaerobic fermentation.There were certainly regional differences in the environmental load index,and the environmental impact effect of anaerobic fermentation was low and more environmentally friendly.These findings provided a technical basis for livestock manure management in different regions of China,which was conducive to promoting animal husbandry emission reduction and carbon sequestration.

Life cycle assessment of urban uses of biochar and case study in Uppsala,Sweden

Biochar is a material derived from biomass pyrolysis that is used in urban applications.The environmental impacts of new biochar products have however not been assessed.Here,the life cycle assessments of 5 biochar products(tree planting,green roofs,landscaping soil,charcrete,and biofilm carrier)were performed for 7 biochar supply-chains in 2 energy contexts.The biochar products were benchmarked against reference products and oxidative use of biochar for steel production.Biochar demand was then estimated,using dynamic material flow analysis,for a new city district in Uppsala,Sweden.In a decarbonised energy system and with high biochar stability,all biochar products showed better climate performance than the reference products,and most applications outperformed biomass use for decarbonising steel production.The climate benefits of using biochar ranged from−1.4 to−0.11 tonne CO_(2)-eq tonne−1 biochar in a decarbonised energy system.In other environmental impact categories,biochar products had either higher or lower impacts than the reference products,depending on biochar supply chain and material substituted,with trade-offs between sectors and impact categories.However,several use-phase effects of biochar were not included in the assessment due to knowledge limitations.In Uppsala’s new district,estimated biochar demand was around 1700 m^(3)year^(−1)during the 25 years of construction.By 2100,23%of this biochar accumulated in landfill,raising questions about end-of-life management of biochar-containing products.Overall,in a post-fossil economy,biochar can be a carbon dioxide removal technology with benefits,but biochar applications must be designed to maximise co-benefits.

Life cycle environmental impact assessment of biochar-based bioenergy production and utilization in Northwestern Ontario,Canada

Biochar-based bioenergy production and sub- sequent land application of biochar can reduce greenhouse gas emissions by fixing atmospheric carbon into the soil for a long period of time. A thorough life cycle assessment of biochar-based bioenergy production and biochar land application in Northwestern Ontario is conducted using SimaPro Ver. 8.1. The results of energy consumption and potential environmental impact of biochar-based bioenergy production system are compared with those of conventional coal-based system. Results show that biocbar land application consumes 4847.61 MJ per tonne dry feedstock more energy than conventional system, but reduces the GHG emissions by 68.19 kg CO2e per tonne of dry feed- stock in its life cycle. Biochar land application improves ecosystem quality by 18 %, reduces climate change by 15 %, and resource use by 13 % but may adversely impact on human health by increasing disability adjusted life years by 1.7 % if biomass availability is low to medium. Replacing fossil fuel with woody biomass has a positiveimpact on the environment, as one tonne of dry biomass feedstock when converted to biochar reduces up to 38 kg CO2e with biochar land application despite using more energy. These results will help understand a comprehensive picture of the new interventions in forestry businesses, which are promoting biochar-based bioenergy production.

Carbon emissions from buildings based on a life cycle analysis:carbon reduction measures and effects of green building standards in China

建筑碳排放约占到中国社会碳排放总量的一半,仅关注建筑运行碳排放容易忽视建筑部门其他相关环节的碳排放,从而拖慢建筑部门碳达峰进度。应用生命周期分析进行建筑全生命期碳排放计算,可以识别建材、建造、运行以及报废拆除各阶段的碳排放表现,从而在建筑设计中更好的制订和实施碳减排策略。中国绿色建筑评价标准主张对建筑进行全生命期碳排放分析,本文构建了绿色建筑全生命期碳排放计算方法,并对获得绿色建筑评价认证的33个项目进行了碳排放情况的汇总分析,发现中国绿色建筑评价标准在降低建筑全生命期碳排放方面作用明显,绿色公共建筑碳排放强度比全国同类建筑运行碳排放低41.43%,绿色居住建筑碳排放强度比全国同类建筑运行碳排放低13.99%。对绿色建筑评价标准内容进行了碳相关性分析,对比了修订前后建筑碳排放强度的变化,发现新版标准对公共建筑的影响大于居住建筑,在建筑全生命期碳排放方面,加强了建材生产阶段碳减排的要求。本研究解决了当前绿色建筑碳减排效果不明确的问题。

Comparison of life cycle assessment of large-scale biogas projects with different raw materials in China

The anaerobic digestion(AD)disposal of stover and cattle manure is of great significance to the development of low-carbon economy and green energy in China,but it will also have an impact on the environment,and the degree of influence is different for various raw materials.In this study,life cycle assessment(LCA)methods were applied to analyze and compare the impact of corn stovers biogas projects(CSBP)and dairy manure biogas projects(DMBP)on the environment during the whole operation stage.The results of inventory analysis were evaluated by ReCiPe2016 Hierarchy(H)mid-point(problem-oriented)and end-point(destruction-oriented)method,respectively.The results showed that the net energy efficiency of CSBP was higher(763.903 kW·h/FU)and the greenhouse gas(GHG)emission reduction of DMBP was more(5541.418 kg CO_(2)-eq/FU).The anaerobic digestion(AD)units have the greatest environmental impacts,and human carcinogenic toxicity is the largest environmental impact category(1.16-1.43 PE).The key to reducing environmental impact is reducing the input of chemical substances and the waste of electric energy.Both CSBP and DMBP have a favorable impact on ecosystem quality and resources,and CSBP is more beneficial to the environment(-10.297 Pt).Co-digestion is an important measure to reduce the environmental damage from biogas projects.These research results provide theoretical support for the selection of raw materials for large-scale biogas projects in China,provide technical basis for reducing the impact of actual operation on the environment,and promote the resource utilization of agricultural waste and carbon dioxide emission reduction and sequestration.

A Quantitative Process-Based Inventory Study on Material Embodied Carbon Emissions of Residential, Office, and Commercial Buildings in China

Studies on building carbon emissions focus mainly on the materialization phase of life cycle, as carbon emissions in this stage is intensive and high. This paper proposes a simplified model to calculate embodied carbon emissions in building design stage by conducting a process-based inventory analysis of carbon emissions from materials used in 129 residential buildings, 41 office buildings, and 21 commercial buildings during materialization phase. The results indicate that average carbon emissions per unit area from building materials used in residential buildings, office buildings, and commercial buildings are 514.66 kgCO2 e/m2, 533.69 kg CO2 e/m2 and 494.19 kgCO2 e/m2, respectively. Besides, ten kinds of building materials(namely, steel, commercial concrete, wall building materials, mortar, copper core cables, architectural ceramics, PVC pipes, thermal insulation materials, doors and windows, and water paint) constitute 99% of total carbon emissions in all three types of buildings. These materials are major carbon emissions sources in materialization phase. Thus, embodied carbon emissions can be significantly reduced by limiting the amount of these materials in architectural design as well as by using environmental friendly materials.

水力发电生命周期评价及碳足迹区域化分析

基于生命周期评价方法,对我国典型水电站水力发电生命周期碳足迹及其他环境影响进行了评估,并分析讨论了不同区域水力发电碳足迹的差异性及原因。结果显示,三峡水电站单位水电碳足迹(以CO_(2)当量计)为12.7 g/(kW·h),主要来源于运行阶段,造成其他环境影响的主要阶段为土建工程阶段,其次为机电设备制造阶段;我国不同省级行政区单位水电碳足迹差距较大,与全国平均值相差±20%以上的省级行政区有24个;各省级行政区运行阶段碳足迹占比为47.94%~96.82%,占比超过80%的省级行政区有19个。研究结果可以为我国及省级发电清单编制与电网结构调整提供数据支撑。

我国化工园区减污降碳技术路径研究

化学工业是推动制造强国战略实施的重要支撑,化工园区是新型工业化的关键载体,开展化工园区减污降碳技术应用研究具有重要的现实意义。本文针对化工园区减污降碳面临的资源利用率低、减污和降碳协同性差、末端治污成本高、环境安全与风险突出等挑战,分析了化工园区碳和污染物产生的特点并梳理相关研究进展,剖析了减污降碳协同增效的内涵。在此基础上,建立了基于一般性工业过程的分析框架,以物质、能量代谢过程为纽带,从企业生产、基础设施、产业共生等层面演绎提出了化工园区减污降碳的技术路径:建立化工园区内企业的碳、污染物排放清单;集成优化化工园区的技术与产业结构,加强绿色低碳生产技术开发、基础设施升级共生、企业间合作、减污降碳与安全生产统筹、产品‒产业‒空间结构优化;开展全生命周期减污降碳成本效益评估。选取杭州湾上虞经济技术开发区为典型案例,总结了化工园区减污降碳技术路径的应用实践,进而提出了化工园区减污降碳实施路径建议:完善精细计量体系,加强化工园区物质流管理;强化化工园区共生链接,运用系统工程赋能减污降碳;激发系统效率变革,推动化工园区绿色高质量发展。

基于LCA的山岭隧道碳排放核算研究现状与展望

首先,梳理山岭隧道碳排放核算研究的进展并进行探讨,基于生命周期评价理论(life cycle assessment,LCA)与排放因子法,结合山岭隧道特点对其全生命周期内各阶段的碳排放来源进行分析,着重探讨施工与运营阶段的计算边界;其次,强调碳排放核算过程中清单分析涉及到的碳排放因子与活动数据的获取方式与应用条件;然后,对核算结果的应用、不确定分析与碳排放预测的相关研究成果进行整理;最后,指出当前山岭隧道碳排放研究中存在的问题,并展望其未来发展方向。

Carbon emission quantification and reduction in pavement use phase:A review

The carbon emissions arising from road pavement infrastructures have emerged as critical issue in recent years.The life cycle of a pavement can be divided into five phases,namely raw materials and production,construction,use,maintenance and end of life.While the use phase generates the highest carbon emissions throughout the pavement's life cycle,it is usually neglected in most pavement life cycle assessment(LCA)studies due to its complexity and uncertainty.Therefore,this review selected 126 relevant references,focuses on quantification methods,influential factors and reduction technologies of carbon emissions in pavement use phase.Among the carbon accounting approached,the LCA approach,remains the most widely used for evaluating the environmental impact of pavements.Second,the primary influential factors on the use phase'carbon emission include pavement-vehicle interaction primarily affected by pavement roughness,pavement albedo and climate change.Most influential factors above indirectly cause changes in carbon emissions by influencing the pavement performance and subsequent vehicle emissions.Finally,the review surveys carbon emission reduction technologies during pavement use phase,focusing mainly on reducing pavement rolling resistance and constructing cool pavements.Reflective pavements and permeable pavements are the most widely used cool pavement technologies.Overall,the aspects involved in this paper hold significant promise for quantifying and reducing carbon emissions in the pavement use phase.

基于实际地铁线路的全生命周期碳排放研究

在双碳战略的重大战略部署下,对轨道交通全生命周期碳排放进行研究,合理量化其碳排放水平是实现交通部门碳达峰、碳中和的重要措施。本文基于北京某新建地铁线路,对轨道交通全生命周期碳排放进行分析,建立了轨道交通全线、全生命周期的碳排放计算模型,并定量计算新建地铁线路全线、全生命周期的碳排放量。同时,对建设阶段和运营阶段的降碳措施做出分析,定量评估其降碳潜力。对全长81 km新建地铁线路进行碳排放量计算,得到建设阶段碳排放量为257万t CO_(2)eq,运营阶段为5.35万t CO_(2)eq/a,50年运营周期总计碳排放量524万t CO_(2)eq。建设阶段使用可再生材料及预制结构可减少碳排放量7%;运营阶段综合采用多种节能降碳措施后,可降碳27%;50年运营周期降碳潜力总计17%。该模型的建立对城轨交通全生命周期碳排放定量计算有指导意义,降碳措施的研究成果以期为城轨交通完成绿色低碳转型、实现交通部门碳达峰、碳中和提供参考。

考虑广义储能和LCA碳排放的综合能源系统低碳优化运行策略

综合能源系统(IES)是当前能源转型低碳发展背景下实现“双碳”目标的关键,为了提高IES碳减排能力,需要充分利用需求侧负荷资源和传统储能设备等广义储能资源参与IES优化.首先,建立一种综合考虑可再生能源、能源转换设备、广义储能设备、能源市场交易的IES优化运行模型.然后,使用生命周期评估法(LCA)对IES中能源循环、设备循环的全过程进行碳排放量计算,并将碳排放成本纳入系统总成本.最后,利用仿真实验验证所提模型不仅有利于降低IES总调度成本,还能降低系统的碳排放量,有效促进IES的低碳发展.

地铁建设期碳排放核算研究进展

全球变暖是人们高度关注的生态环境问题之一,碳排放成为研究热点。交通运输行业会产生大量能耗,地铁作为一种安全环保的交通方式正高速建设,建筑行业又具有较大减排空间,故对地铁建设期碳排放进行核算有助于预测碳排放趋势并为碳减排提供研究基础。本研究总结了地铁建设期碳排放核算在评估方法选择、系统边界划分、清单分析等方面的研究进展,学者们多基于全生命周期理论,使用排放因子法,将碳排放来源划分为建材生产、材料运输和现场施工3个阶段开展碳排放研究。本研究就现有清单分析内容进行了对比分析,发现建材生产阶段碳排放占比最大,且钢筋、混凝土、水泥是主要的高碳排建材,依此提出了地铁建设碳排放核算的基本研究方法及减排思路。

低碳氨燃料生命周期碳排计算和应用前景探究

文章梳理了低碳氨的燃料属性和特点,测算了目前技术水平下低碳氨生命周期碳排因子,对低碳氨与煤制氨的成本进行了分析,指出随着技术进步成本进一步下降,风光发电制低碳氨燃料经济性将逐步体现,未来具有发展空间。低碳氨生命周期碳排因子生产环节排放占90%以上,生产环节中碳排基本上是制氢和制氮用电导致,因此降低碳排主要方向是减少生产环节用电量和尽可能增加绿电使用量。