A database tool for systematic analysis of embodied emissions in buildings and neighborhoods

There is a growing body of research on the embodied emissions of individual buildings, but the results and methods remain mostly inaccessible and incomparable due to insufficient reported information, and differences in system boundaries, methods, and data used. This inhibits further utilization of the results in statistical applications and makes interpretation and validation of results difficult. The database tool presented in this paper attempts to mitigate these challenges by systematizing and storing all relevant information for these studies in a compatible format. The tool enables comparison of results across system boundaries, improves the transparency and reproducibility of the assessments, and makes utilization of the results in statistical applications possible. Statistical applications include embodied emission benchmarking, identifying emission drivers, and quantifying relationships between variables. Other applications of the tool include the assessment of embodied emissions of buildings and neighborhoods. This paper presents the tool and exemplifies its use with preliminary results based on a dataset of 11 buildings. Work is ongoing to expand the dataset, which will provide more comprehensive results

FutureBuilt Zero - A simplified dynamic LCA method with requirements for low carbon emissions from buildings

FutureBuilt is a voluntary program for ambitious low-carbon construction projects. To incentivize measures that lead to the lowest climate change impact from all aspects of buildings and according to national Paris agreement pledges, FutureBuilt Zero introduces an ambition level and a novel calculation methodology for net climate change impacts over the life of a building. The ambition level is tightened over time to help Norway achieve its climate goals. A comprehensive simplified calculation method is introduced, which considers how the timing of emissions during the building life affects the contribution to global warming. Both direct and indirect emissions throughout the lifetime are included; energy use in operation and at the construction site, material production and transport of materials to the construction site, and waste management (incineration). In addition, the climate-positive effects of biogenic carbon uptake, carbonation of cement, potential for future reusability, and exported energy are included. This paper presents the criteria, describes the method and the scientific basis as well as the principles and logic behind the choices made.publishedVersio

Metode for klimagassberegninger av bygg - ZEN-case for test og sammenligning av NS 3720 og FutureBuilt Zero

For å kunne kvantifisere utviklingen av et nullutslippsområde er klimagassutslipp fra materialer og energibruk i drift viktige indikatorer. Det er utviklet en standard for metode for klimagassberegninger for bygninger – NS 3720:2018 som benyttes for å kvantifisere klimagassutslippene gjennom hele levetiden til et bygg. I tillegg har FutureBuilt satt i gang arbeid med utvikling av metodikk og kriterier for FutureBuilt Zero, som inkluderer klimagassutslipp fra alle faser i byggets levetid; anleggs-virksomhet, transport av materialer, materialbruk og materialsvinn, vedlikehold, energibruk i drift og avhending/ombruk/gjenvinning. Denne rapporten viser fremgangsmåte og resultater i et ZEN-case basert på å vurdere ulike metodiske valg knyttet til klimagassberegninger, henholdsvis med metodikken i NS 3720 og ut fra kriteriene i FutureBuilt Zero, og hvilken effekt disse valgene har på resultatene fra klimagassberegninger for et antall bygg. Det er gjennomført klimagassberegninger for tre eksempelprosjekter (Kristian August gate 13 – nybygg, Kristian August gate 13 – eksisterende bygg, og Høyblokk), der detaljert informasjon er benyttet både ved bruk av NS 3720 metoden og ved bruk av kriteriene i FutureBuilt Zero. På bakgrunn av resultatene fra disse beregningene visualiseres det hvordan de metodiske forskjellene i beregningen av klimagassutslipp i livsløpet til bygg kan påvirke sluttresultatet og ikke minst den relative betydningen av forskjellige livsløpsmoduler og utslippskilder. Dette vil igjen kunne påvirke metodiske valg og dernest hvilke tiltak som blir besluttet gjennomført i praksis for å redusere klimagassutslipp for fremtidige prosjekter. Resultatene fra denne studien viser at valg av metode og regneregler vil ha betydelig innvirkning på de beregnete klimagassutslippene og derfor vil kunne påvirke metodiske valg og prioritering av hvilke utslippsreduksjonstiltak som kan tenkes gjennomført i praksis.publishedVersio

A holistic model for analyzing energy benefits of urban density by relating energy use, building height, and overall city structure

More than half of the world population live in cities, and the urban population is further expected to almost double within 2050. This opens a rare window of time for realizing energy savings through overall city planning. How the overall city structure influence energy consumption is, however, still poorly understood. A central theme in the sustainable development of urban form is the compact city, and as a key instrument of this densification, tall buildings may prove important. Yet, the overall energy-saving potential of building taller and denser remain largely unclear. Moreover, current studies are described as far from holistic, not capturing the interconnectedness and complexity of the system as a whole. They are mostly qualitative, and methods depend largely on context. There is thus a lack of a clear theoretical framework for understanding energy consumption at the urban scale. The ambition of this thesis is to address this knowledge gap. This thesis develops a holistic optimization model for investigating the extent to which urban density and urban structure influence the energy consumption of the urban system. Energy aspects in land use planning, including the influence of building height, are addressed. The model relates energy costs of building heights of three stories and greater, with transportation and infrastructure energy benefits of building denser. Multiple scenarios of differing climate, population, and other variables have been simulated. Only factors considered to be correlated with urban density are taken into account. Of these, solar irradiation and the urban heat island effect have been left out due to their complex nature. A denser and taller city structure than what is normal in cities today is found to be optimal for low urban energy use. The most influential urban density indicators are embodied energy (most heavily influenced by building lifetime) and floor area per capita. The findings of the research indicate that building heights approximately in the range 7-27 stories are optimal for a given population and building lifetime. For buildings taller than this the increased embodied energy outweighs further reduction potentials of other elements. Energy use per capita in a city with optimal density is increasing slightly with population. Transportation energy is found to be much less important than building energy, especially in dense small area scenarios, but becomes increasingly important for low-density scenarios with large urban areas. Road construction, elevator energy, and vertical water transportation energy does not significantly affect the overall energy budget. An energy saving potential for the urban metabolism of the investigated elements of approximately one-third compared to a low-density scenario is found to be viable. However, energy savings of further densification in areas that already have high-density, close to the optimal, are not significant. The energy expenditure is significantly lower in the dense and tall scenarios - with implications for current and near-future city planning policies on optimizing land use based on city size. These findings improve the basis on which decisions are made for policy-makers and urban planners worldwide, although the significance of solar irradiation and the urban heat island effect should be investigated further. The model is a generalized theoretical abstraction and thus has its limitations. Further development of the model by including more elements as well as reducing uncertainties is needed. Nevertheless, the findings are relevant both for further development of existing cities and for conceptually planned future cities

Embodied emission profiles of building types: Guidance for emission reduction in the early phases of construction projects

The embodied emissions of the construction materials in buildings are a significant contributor to climate change but have only rarely been systematically studied by statistical methods. In the early phases of a building project, empirical results of statistical emission profiles of different building types can act as useful guiding information to inform decisions regarding reduced embodied emissions from construction materials. However, engineers and architects do not have such information at disposition. In this paper, the embodied emissions from the production and transport of initial and recurring building material use in 7 Norwegian case studies of low-emission buildings are made comparable and then studied statistically to find out how the impact varies with building types. The building types studied are timber residential, concrete office, concrete school, and concrete swimming hall. Statistics are produced for each building type and are broken down by the impact contribution from different building elements and material categories. This results in embodied emission profiles and material use profiles for these four building types, which, when based on a larger dataset, can be used by architects and engineers to make informed decisions when aiming for reduced embodied emissions in the early phases of a construction project. Additionally, these profiles can be used as benchmarks by which the final building can be compared when the building is constructed. The statistical results are preliminary and based on a limited dataset, which makes them applicable only as an indication for Norwegian low-emission buildings of these four building types. Future work includes expansion of the dataset on which the profiling is based, further development of the statistical method, and applying the methodology to additional building types

The Role of Utility Companies In Municipal Planning of Smart Energy Communities

Bergen and Oslo municipalities focus on integrating energy concerns into city planning and regard this as an opportunity to further lower greenhouse gas emissions. Due to a lack of tools and clear definitions of what Smart Energy Communities (SECs) are and how planning should be done in order to affect the overarching emission reduction goals, utility companies end up taking a leading role as advisors and influence definitions and strategies in the final design. Based on two case studies of SEC projects in Norway, the authors highlight the need for increased work to create feasible and understandable definitions and strategies for the planning of SECs. In our case studies, city planners struggle to include energy aspects in the early planning phase and to align their objectives of citizen well-being and reduced private car dependency with energy concerns. At the same time, utility companies respond to the perceived threat of more self-sufficient communities by depicting a role closer to the end-user and by offering a pragmatic cost/benefit view on the planning of energy supply options

An analytical method for evaluating and visualizing embodied carbon emissions of buildings

Greenhouse gas emissions associated with buildings constitute a large part of global emissions, where building materials and associated processes make up a significant fraction. These emissions are complicated to evaluate with current methodologies due to, amongst others, the lack of a link between the material inventory data and the aggregated results. This paper presents a method for evaluating and visualizing embodied emission (EE) data of building material production and transport, including replacements, from building life cycle assessments (LCAs). The method introduces a set of metrics that simultaneously serve as a breakdown of the EE results and as an aggregation of the building's inventory data. Furthermore, future emission reductions due to technological improvements are modeled and captured in technological factors for material production and material transport. The material inventory is divided into building subparts for high-resolution analysis of the EE. The metrics and technological factors are calculated separately for each subpart, which can then be evaluated in relation to the rest of the building and be compared to results from other buildings. Two methods for evaluating and visualizing the results are presented to illustrate the method's usefulness in the design process. A case study is used to demonstrate the methods. Key driving factors of EE are identified together with effective mitigation strategies. The inclusion of technological improvements shows a significant reduction in EE (−11.5%), reducing the importance of replacements. Furthermore, the method lays the foundation for further applications throughout the project phases by combining case-specific data with statistical data

An analytical method for evaluating and visualizing embodied carbon emissions of buildings

Greenhouse gas emissions associated with buildings constitute a large part of global emissions, where building materials and associated processes make up a significant fraction. These emissions are complicated to evaluate with current methodologies due to, amongst others, the lack of a link between the material inventory data and the aggregated results. This paper presents a method for evaluating and visualizing embodied emission (EE) data of building material production and transport, including replacements, from building life cycle assessments (LCAs). The method introduces a set of metrics that simultaneously serve as a breakdown of the EE results and as an aggregation of the building's inventory data. Furthermore, future emission reductions due to technological improvements are modeled and captured in technological factors for material production and material transport. The material inventory is divided into building subparts for high-resolution analysis of the EE. The metrics and technological factors are calculated separately for each subpart, which can then be evaluated in relation to the rest of the building and be compared to results from other buildings. Two methods for evaluating and visualizing the results are presented to illustrate the method's usefulness in the design process. A case study is used to demonstrate the methods. Key driving factors of EE are identified together with effective mitigation strategies. The inclusion of technological improvements shows a significant reduction in EE (−11.5%), reducing the importance of replacements. Furthermore, the method lays the foundation for further applications throughout the project phases by combining case-specific data with statistical data