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Goal, Scope and Background. LEED (Leadership in Energy and Environmental Design) is a scoring system that evaluates the environmental friendliness of,buildings. It is composed of 69 credits, each one providing a score of one (i.e., one point) if implemented. However, since each credit does not always provide the same type and magnitude of benefits for the environment, a higher rating is not always synonymous with lower impacts. The goal of this paper is to evaluate the actual extent of the benefits and burdens of LEED, identify the critical credits and develop a new scale that will correct these miscorrelations.Methods. The various LEED credits are qualitatively analysed. It is possible to quantify the actual outcomes and thus perform a lifecycle assessment (LCA) on 45 credits applied to an actual California office building. This allows comparing the benefits of the different credits among each other. Commuting of the employees is included in the system. The LCA is performed with the help of SimaPro 7, combining the ecoinvent 1.2 inventory database and the impact assessment methodology IMPACT 2002+ v2.1, adapted to North America. Impacts are evaluated for human health, ecosystems quality, climate change, and resource consumption. Impacts of the different credits are aggregated in one indicator to allow the design of a new scoring system that assigns to the different credits an amount of points (i.e., a score) that are related to the actual benefits. A school and a residential building are also modeled in order to perform a sensitivity study.Results and Discussion. Operation, especially employee commuting and electricity consumption, dominates the impacts associated with the building. It appears that waste generation have limited but not negligible impacts, whereas water consumption has small impacts. Since the building is situated in California, heating is not an important source of impacts. As a result, credits that provide the most environmental benefits are the ones geared toward increasing the fraction of green electricity, reducing energy consumption, reducing employee commuting, and increasing waste recycling, along with the ones favoring the reuse and recycling of the building structure. The ones targeting reduction of water and land use, and recycling content in the furniture appear to be less beneficial. The scores of the different LEED credits range from -128 to 606. Negative credits are due to credits that lead to more burdens than benefits, for example, the one requiring the construction of a multifloor parking lot (with a score of -128). The most beneficial credit (with a score of 606) is the one requiring that electricity comes from at least 50% green power.Conclusions and Outlook. Comparing the new scale with the observations on site shows that the LEED credits actually implemented are not always the most beneficial for the environment. This issue should be addressed in order to make LEED more efficient. The proposed rating system should help correct these discrepancies. The amount of reduction in employee commuting that the related credits really achieve, actual impacts of land and water use, along with the benefits of improved indoor air quality are among the main future challenges of the present study.

Purpose: How to build in more environmentally sustainable manner? This issue is increasingly coming to the fore in construction sector, which is responsible for a relevant share of resource depletion, solid waste, and greenhouse gas (GHG) emissions. Carbon-reinforced concrete (CRC), as a disruptive innovation of composite building material, requires less resources and enables new forms — but does it make CRC more environmentally sustainable than steel-reinforced concrete (SRC)? This article aims to assess and compare the environmental impact of 45 material and production scenarios of a CRC with a SRC double wall. Methods: The life cycle assessment method (LCA) is used to assess environmental impacts. The functional unit is a double wall and the reference flows are 1 m3 for concrete and 1 kg for fiber. CML methodology is used for life cycle impact assessment (LCIA) in the software GaBi© ts 10.0. A sensitivity analysis focuses on electricity grid mixes, concrete mixes, and steel production scenarios. Results: The midpoint indicator climate change respective global warming potential (in kg CO2e) ranges between 453 kg CO2e and 754 kg CO2e per CRC double wall. A comparable SRC double wall results in emissions of 611–1239 kg CO2e. Even though less raw material is needed for CRC, it does not represent a clear advantage over SRC in terms of climate change. In a comparison, the production of steel (blast furnace vs. electric arc furnace vs. recycled steel) and the choice of cement type are of decisive relevance. For concrete mixes, a mixture of Portland cement and blast furnace slag (CEM III) is beneficial to pure Portland cement (CEM) I. For fiber production, styrene-butadiene rubber (SBR) has an advantage over epoxy resin (EP) impregnation and the use of renewable energy could reduce emissions of fiber production up to 60%. Conclusion: CRC requires less material (concrete cover) than SRC, however, exhibits comparable CO2e to SRC — depending on the production process of steel. In the future, fiber production and impregnation should be studied in detail. Since in terms of climate change neither wall (CRC vs. SRC) clearly performs better, the two other pillars of sustainability (economic and social, resulting in LCSA) and innovative building components must be focused on. [ABSTRACT FROM AUTHOR]

ISO 14044, clause 5.2 only requires that third-party reports "shall be made available to any third party to whom the communication is made" (ISO [2]). More broadly, it should be noted that sector-specific ISO standards, such as ISO 21930, cannot overrule generic ISO management standards. Since the above ambiguities appear to be reasonable interpretations of the current language in ISO 14044, they should be addressed and clarified by future ISO/TC207/SC5 Working Groups, e.g., when revising ISO/TS 14071:2014. 8. ISO/IEC Directives, Part 1 - Consolidated ISO Supplement - Procedures specific to ISO. [Extracted from the article]

Background, Aims and Scope Telework is associated with a number of costs and benefits, including reduced company overhead costs, need for office and parking space, office energy consumption, increased productivity, reduced absenteeism, retention of specialized employees, reduction in transportation-related fuel consumption and air pollution, and many others. This paper applies a systems model to telework and nontelework scenarios to quantify direct energy and fuel costs and external costs related to air emissions from transportation, heating, cooling, lighting, and electronic and electrical equipment use both at the company and the home office, including rebound effects. Methods: E-COMMUTair, a scalable web-based tool created by the authors and designed to assess the air pollution effects of individual or company telework programs versus nontelework is employed along with Monte Carlo simulation and sensitivity analysis. E-COMlvIUTair is using the latest available U.S. energy use and air emission factors. The external costs of air emissions are estimated. The role of telecommuting frequency is emphasized, and differences between various states are explored. The paper identifies the drivers of external costs, and presents an example breakeven analysis focused on CO2 and key model parameters. Results and Discussion: Nonteleworks external costs are equal to or higher than teleworks costs for every model component, demonstrating that telework programs could provide benefits, including monetary benefits, to society. Transportation is the major contributor to the total costs, with home heating and cooling, and office cooling following. Most of the monetary costs associated with transportation are borne by individuals rather than society. Teleworking employees increase their home- related expenses but reduce their travel-related expenses, ending up with smaller total costs. Energy and fuel costs get reduced in the office space when telework programs are applied, resulting in benefits to companies. Energy and external costs decrease as telework frequency increases. When compared to not teleworking, 5-day telework scenarios on cooling days in California can have about 50-70% lower total costs. The probabilistic analysis confirms the results of the deterministic analysis. The sensitivity analysis reveals that for the nontelework scenario, transportation-related variables such as commuting distance and average number of passengers affect GO2, GO, and NO~ emissions, while for the telework part, frequency and the number of roundtrips are the most relevant. Conclusions: Both analyses show that telework programs have the potential to lower both energy and external costs creating a favorable bottom line for society, employees, and companies by decreasing tailpipe emissions, lowering transportation costs, and decreasing energy costs at the company office. However, important parameters such as telecommuting frequency, characteristics of the office and home space, climate patterns, and rebound effects that determine external costs along with the price of gasoline, electricity and natural gas in the state where the program is implemented can greatly influence the final results, and should be carefully examined. Recommendations and Perspectives: The effects of telework programs on peoples daily lives are complex and difficult to predict and quantify. The current analysis showed that significant financial benefits can be expected from telework programs, but as seen often in environmental policy-making, the details of implementation will make or break the success of a program. [ABSTRACT FROM AUTHOR]

Background, Aims and Scope. Life cycle assessment models typically use product-specific, plant-level or national aggregate data. However, many decisions by regional policy makers would be better informed by local or regional aggregate data. This research is in- tended to construct and apply a regional US economic input-output analysis-based life cycle assessment (REIO-LCA) model based upon publicly available datasets. The model uses Gross State Product (GSP) estimates to calculate regional economic multipliers and then link them to regional electricity and fuel use, and air emission factors. Target audiences are governmental decision makers, industry experts and researchers concerned with the regional economic and environmental effects of public and private decisions. Methods. A regional version of the existing US EIO-LCA model was developed using regional economic multipliers and state environmental data. The national model is based on the US 491 by 491 leconomic input-output model, and uses sectoral energy consumption and emission factors to approximate the environmental effects of production and services. The proportion of the regional value added (Gross State Product) to the national value added for each sector was used to develop economic multipliers to allocate the output of industries to individual states and multi-state regions. Inter-sectoral transaction matrices were constructed for eight regions. Regional environmental emission and resource use factors were formed based upon publicly available data of the US Environmental Protection Agency (EPA) and Department of Energy. The Toxics Release Inventory include facility location parameters, enabling the estimation of sectoral toxic emissions for the regions. The national electricity and fuel use, air pollutants (CO, NOR, PM10, SO2 and VOC) and greenhouse gas emissions used by the ElO-LCA model were proportioned based upon state totals for each sector. Results. A regional economic input-output model was created for US regions, and sectoral energy use and environmental emission factors were estimated for Pennsylvania, the Far West (Alaska, California, Hawaii, Nevada, Oregon and Washington) and the Mideast (Delaware, District of Columbia, Maryland, New Jersey, New York and Pennsylvania) economic areas. The use of the framework for regional IO-LCA model is demonstrated through two case studies. Discussion. As a validation exercise, the regional outputs of petroleum refineries were calculated using the regional input-output matrices and the outcomes were compared to the Energy Information Administrations (EIA) Petroleum State Profile data. The model results show that approximately 70% of the total national sectoral production takes place in three regions, i.e., South West, South East and Far West, which corresponds with the EIA statistics. The REIO-LCA model constructed for the Far West is used to conduct a second case study estimating the annual toxic air emissions of power plants in the region in 2003. The results are evaluated by comparison to data provided by the US EPA. The estimated pollutions do not differ significantly from those presented in the Toxics Release Inventory reports. Conclusions. The usefulness of IO LCA models can be improved through the incorporation of local economic and environmental characteristics. Wiht the lack of US regional sectoral data, the allocation of national industrial production to regions can provide a frame- work to create smaller scale JO models. The results of case studies support the assumption that the GSP multipliers may be used to allocate the sectoral production to the regions, and show that the frame- work IO LCA model provides a reasonable approximation of supply chain economic activities and environmental effects caused by production and services. Recommendations and Perspectives.… [ABSTRACT FROM AUTHOR]

Goal, Scope and Background. This paper discusses the merging of methodological aspects of two known methods into a hybrid form applied to water supply systems. Water shortages are imminent due to scarce supply and increasing demand in many parts of the world. In California, this is caused primarily by population growth. As readily available water is depleted, alternatives that may have larger energy and resource requirements and, therefore, environmental impacts must be considered. In order to develop a more environmentally responsible and sustainable water supply system, these environmental implications should be incorporated into planning decisions. Methods. Comprehensive accounting for environmental effects requires Life Cycle Assessment (LCA), a systematic account of resource use and environmental emissions caused by extracting raw materials, manufacturing, constructing, operating, maintaining, and decommissioning the water infrastructure. In this study, a hybrid LCA approach, combining elements of process-based and economic input-output-based LCA was used to com- pare three supply alternatives: importing, recycling, and desalinating water. For all three options, energy use and air emissions associated with energy generation, vehicle and equipment operation, and material production were quantified for life-cycle phases and water supply functions (supply, treatment, and distribution). The Water-Energy Sustainability Tool was developed to inform water planning decisions. It was used to evaluate the systems of a Northern and a Southern California water utility. Results and Discussion. The results showed that for the two case study utilities desalination had 2-5 times larger energy demand and caused 2-18 times more emissions than importation or recycling, due primarily to the energy-intensity of the treatment process. The operation life-cycle phase created the most energy consumption with 56% to 90% for all sources and case studies. For each water source, a different life-cycle phase dominated energy consumption. For imported water, supply contributed 56% and 86% of the results for each case study; for desalination, treatment accounted for approximately 85%; for recycled water, distribution dominated with 61% and 74% of energy use. The study calculated external costs of air pollution from all three water supply systems. These costs are borne by society, but not paid by producers. The external costs were found to be 6% of desalinated water production costs for both case studies, 8% of imported water production costs in Southern California, and 1-2% for the recycled water systems and for the Northern California utilitys imported water system. Conclusion. Recycling water was found to be more energy intensive in Northern than in Southern California, but the results for imported water were similar. While the energy demand of water recycling was found to be larger than importation in Northern California, the two alternatives were competitive in Southern California. For all alternatives in both case studies, the energy consumed by system operation dominated the results, but maintenance was also found to be significant. Energy production was found to be the largest contributor in all water provision systems, followed by materials production. The assessment of external costs revealed that the environmental effects of energy and air emissions caused by infrastructure is measurable, and in some cases, significant relative to the economic cost of water. Recommendation and Perspective. This paper advocates the necessity of LCA in water planning, and discusses the applicability of the described model to water utilities. [ABSTRACT FROM AUTHOR]

Goal, Scope and Background. This study provides a life-cycle inventory of air emissions (CO2, NOx, PM10, and CO) associated with the transportation of goods by road, rail, and air in the U.S. It includes the manufacturing, use, maintenance, and end-of-life (EOL) of vehicles, the construction, operation, maintenance, and EOL of transportation infrastructure, as well as oil exploration, fuel refining, and fuel distribution. Methods. The comparison is performed using hybrid life-cycle assessment (LCA), a combination of process-based LCA and economic input-output analysis-based LCA (EIO-LCA). Results are summed by means of a common functional unit of grams of air pollutant per ton-mile of freight activity. Results and Discussion. Results show that the vehicle use phase is responsible for approximately 70% of total emissions of CO2 for all three modes. This confirms that tailpipe emissions underestimate total emissions of freight transportation as infrastructure, pre-combustion, as well as vehicle manufacturing and EOL account for a sizeable share of total emissions. Depending on mode and pollutant, differences between tailpipe emissions and total systemwide emissions can range from only 4% for road transportations CO emissions to an almost tenfold difference for air transportations PM10 emissions. Conclusion. Rail freight has the lowest associated air emissions, followed by road and air transportation. Depending on the pollutant, rail is 50–94% less polluting than road. Air transportation is rated the least efficient in terms of air emissions, partly due to the fact that it carries low weight cargo. It emits 35 times more CO2 than rail and 18 times more than road transportation on a ton-mile basis. It is important to consider infrastructure, vehicle manufacturing, and pre-combustion processes, whose life-cycle share is likely to increase as new tailpipe emission standards are enforced. Recommendation and Outlook. Emission factors, fuel efficiency, and equipment utilization contribute the most to uncertainty in the results. Further studies are necessary to address all variables that influence these parameters, such as road grade, vehicle speed, and vehicle weight. A focus on regional variation, EOL processes, fuel refining processes, terminals, as well as more accurate infrastructure allocation between freight and passenger transportation would strengthen the model. [ABSTRACT FROM AUTHOR]