Building Material Use and Associated Environmental Impacts in China 2000-2015.

A rapidly increasing use of building materials poses threats to resources and the environment. Using novel, localized life cycle inventories and building material intensity data, this study quantifies the resource use of building materials in mainland China and evaluates their embodied environmental impacts. Newly built floor area and related material consumption grew 11% per annum from 2000 to 2015, leveling off at the end of this period. Concrete, sand, gravel, brick, and cement were the main materials used. Spatially, construction activities expanded from east China into the central part of the country. Cement, steel, and concrete production are the key contributors to associated environmental impacts, e.g., cement and steel each account for around 25% of the global warming potential from building materials. Building materials contribute considerably to the impact categories of human toxicity, fossil depletion, and global warming, emphasizing that greenhouse gas emissions should not be the sole focus of research on environmental impacts of building materials. These findings quantitatively shed light on the urgent need to reduce environmental impacts and to conserve energy in the manufacturing processes of building materials on the national scale.

Environmental Impact of Buildings--What Matters?

The goal of this study was to identify drivers of environmental impact and quantify their influence on the environmental performance of wooden and massive residential and office buildings. We performed a life cycle assessment and used thermal simulation to quantify operational energy demand and to account for differences in thermal inertia of building mass. Twenty-eight input parameters, affecting operation, design, material, and exogenic building properties were sampled in a Monte Carlo analysis. To determine sensitivity, we calculated the correlation between each parameter and the resulting life cycle inventory and impact assessment scores. Parameters affecting operational energy demand and energy conversion are the most influential for the building's total environmental performance. For climate change, electricity mix, ventilation rate, heating system, and construction material rank the highest. Thermal inertia results in an average 2-6% difference in heat demand. Nonrenewable cumulative energy demand of wooden buildings is 18% lower, compared to a massive variant. Total cumulative energy demand is comparable. The median climate change impact is 25% lower, including end-of-life material credits and 22% lower, when credits are excluded. The findings are valid for small offices and residential buildings in Switzerland and regions with similar building culture, construction material production, and climate.

Housing and mobility demands of individual households and their life cycle assessment.

Household consumption, apart from governmental consumption, is the main driver of worldwide economy. Attached to each household purchase are economic activities along the preceding supply chain, with the associated resource use and emissions. A method to capture and assess all these resource uses and emissions is life cycle assessment. We developed a model for the life cycle assessment of housing and land-based mobility (excluding air travel) consumption of individual households a small village in Switzerland. Statistical census and dwelling register data are the foundations of the model. In a case study performed on a midsized community, we found a median value of greenhouse gas emissions of 3.12 t CO2 equiv and a mean value of 4.30 t CO2 equiv per capita and year for housing and mobility. Twenty-one percent of the households in the investigated region were responsible for 50% of the total greenhouse gas emissions, meaning that if their emissions could be halved the total emissions of the community would be reduced by 25%. Furthermore, a cluster analysis revealed that driving factors for large environmental footprints are demands of large living area heated by fossil energy carriers, as well as large demands of motorized private transportation.

EUBUCCO v0.1: European building stock characteristics in a common and open database for 200+ million individual buildings.

Building stock management is becoming a global societal and political issue, inter alia because of growing sustainability concerns. Comprehensive and openly accessible building stock data can enable impactful research exploring the most effective policy options. In Europe, efforts from citizen and governments generated numerous relevant datasets but these are fragmented and heterogeneous, thus hindering their usability. Here, we present EUBUCCO v0.1, a database of individual building footprints for ~202 million buildings across the 27 European Union countries and Switzerland. Three main attributes - building height, construction year and type - are included for respectively 73%, 24% and 46% of the buildings. We identify, collect and harmonize 50 open government datasets and OpenStreetMap, and perform extensive validation analyses to assess the quality, consistency and completeness of the data in every country. EUBUCCO v0.1 provides the basis for high-resolution urban sustainability studies across scales - continental, comparative or local studies - using a centralized source and is relevant for a variety of use cases, e.g., for energy system analysis or natural hazard risk assessments.

Global scenarios of resource and emission savings from material efficiency in residential buildings and cars.

Material production accounts for a quarter of global greenhouse gas (GHG) emissions. Resource-efficiency and circular-economy strategies, both industry and demand-focused, promise emission reductions through reducing material use, but detailed assessments of their GHG reduction potential are lacking. We present a global-scale analysis of material efficiency for passenger vehicles and residential buildings. We estimate future changes in material flows and energy use due to increased yields, light design, material substitution, extended service life, and increased service efficiency, reuse, and recycling. Together, these strategies can reduce cumulative global GHG emissions until 2050 by 20-52 Gt CO2-eq (residential buildings) and 13-26 Gt CO2e-eq (passenger vehicles), depending on policy assumptions. Next to energy efficiency and low-carbon energy supply, material efficiency is the third pillar of deep decarbonization for these sectors. For residential buildings, wood construction and reduced floorspace show the highest potential. For passenger vehicles, it is ride sharing and car sharing.

A database seed for a community-driven material intensity research platform.

The data record contains Material Intensity data for buildings (MI). MI coefficients are often used for different types of analysis of socio-economic systems and in particular for environmental assessments. Until now, MI values were compiled and reported ad-hoc with few cross-study comparisons. We extracted and converted more than 300 material intensity data points from 33 studies and provide the results in a comprehensive and harmonized database. Material intensity is reported as kilograms per gross floor area for 32 materials as primary data points. Furthermore, we augmented the data with secondary attributes for regional information, such as climate and socioeconomic indicators. The data are hosted on the version control platform GitHub using accessible data formats and providing detailed contribution guidelines. This "database seed" facilitates data analysis, accessibility, and future data contributions by the research community. In the Technical Validation we illustrate that consistency of the data and opportunities for further analysis. This database can serve scientists from various disciplines as a benchmark to determine typical ranges and identify outliers.

A comparative study on the environmental impact of greenhouses: A probabilistic approach.

The aim of this study is to investigate the most important drivers of environmental impacts and identify the influence of parameters on the uncertainty of the environmental impacts in various climate zones and future climate scenarios. We couple a combined greenhouse energy demand-yield simulation tool with a life cycle assessment to identify the drivers for greenhouse energy, water and CO2 demand as well as yield production. Environmental impacts are evaluated using the methods of IPPC for assessing climate change and available water remaining (AWARE) for water scarcity impacts. Furthermore, we compare the results for all five main climate world regions. With a global sensitivity analysis, we identify the parameters with the highest influence on life-cycle impact for each region. Crop growth features (e.g. node development rate and plant density), energy systems (e.g. heating and cooling supply systems), cover materials and inside temperature are the most influential input parameters for climate change impacts, but the ranking between these parameters depends on the location and climatic conditions of the greenhouse. In cold climates and higher latitudes, heating and electricity (mostly for lighting) processes are on average responsible for 85 to 90% of total climate change impacts. In hot climates, active cooling, in addition to natural ventilation, as well as electricity processes rank the highest (in the range of 60 to 75%) and in moderate climates, heating and cooling systems account for 60 to 70% of climate change impacts. Also for the AWARE results, crop growth related parameters are most influential. Among different processes in greenhouse, irrigation is responsible for 90% of water impacts in all regions, but the absolute magnitude of impact varies greatly among the different greenhouse locations.