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Hybrid life cycle assessment (HLCA) strives to combine process‐based life cycle assessment (PLCA) and environmentally extended input–output (EEIO) analysis to bridge gaps of both methodologies. The recent development of HLCA databases constitutes a major step forward in achieving complete system coverage. Nevertheless, current applications of HLCA still suffer from issues related to incompleteness of the inventory and data gaps: (1) hybridization without endogenizing the capital inputs of the EEIO database leads to underestimations, (2) the unreliability of price data hinders the application of streamlined HLCA for processes in some sectors, and (3) the sparse coverage of pollutants in multiregional EEIO databases limits the application of HLCA to a handful of impact categories. This paper aims at offering a methodology for tackling these issues in a streamlined manner and visualizing their effects on impact scores across an entire PLCA database and multiple impact categories. Data reconciliation algorithms are demonstrated on the PLCA database ecoinvent3.5 and the multiregional EEIO database EXIOBASE3. Instead of performing hybridization solely with annual product requirements, this hybridization approach incorporates endogenized capital requirements, demonstrates a novel hybridization methodology to bypass issues of price unavailability, estimates new pollutants to EXIOBASE3 environmental extensions, and thus yields improved inventories characterized in terms of 13 impact categories from the IMPACT World+ methodology. The effect of hybridization on the impact score of each process of ecoinvent3.5 varied from a few percentages to three‐fold increases, depending on the impact category and the process studied, displaying in which cases hybridization should be prioritized. This article met the requirements for a Gold—Gold JIE data openness badge described at http://jie.click/badges.

Over 93% of Norway's power production stems from hydropower. The Nordic power market is constantly transforming, current main drivers include climate change effects on hydrology, an increase of variable renewable energy production, increasing interconnector capacity, and revision of concession terms for hydropower plants. A common plant layout is comprised of a reservoir and an underground penstock leading to a downstream located hydropower plant (HPP); in many cases several reservoirs and power plants are interconnected in complex systems. Consequently, the natural hydrology of many lakes and rivers are heavily impacted by hydropower operation.Hydropower operation is legally regulated by concessions that include regulations to limit negative environmental and societal impacts. More than 400 HPPs currently undergo a revision of terms of their concessions, which will likely impact hydropower operations and subsequently the Nordic power market. Updated or new environmental restrictions of three main types may have significant impact: 1) r 2) requirements for minimum discharge and restricted flow variation downstream of power plants and 3) filling requirements for hydropower reservoirs for the summer season. The joint effect likely has impacts on the power-balance and the hydropower system’s flexibility at multiple timescales from seconds to seasons.The objective of this cross-disciplinary study was to investigate the impacts of an ensemble of updated or new environmental restrictions on hydropower operations and on the Norwegian power market in the future. We developed a nationwide framework to quantify probable future environmental restrictions. . Additionally, a market model dataset for a 2030 scenario was created and input data adjusted, e.g. energy mix development in grid-coupled regions such as central Europe. Implemented in a state-of-the-art market optimization model, we modelled a range of restriction scenarios for the year 2030,We analyzed resulting future price scenarios. Preliminary results show an increase in average yearly production loss in the range of 5 TWh (or 3% of total hydropower production) due to new environmental restrictions. Modelled market response is an increase of average spot-price by about 0.8 €/MWh for all regions of Norway. Norwegian export of electricity to other countries is reduced. Another effect is that reservoir filling levels are typically higher than in the current situation, likely due to filling restrictions and model tendencies to avoid risk of violating reservoir filling restrictions, as well as increased inflow during winter.

Electrification of transport is an important option to reduce greenhouse gas emissions. Although many studies have analyzed emission implications of electric vehicle charging, time-specific emission effects of charging are inadequately understood. Here, we combine climate protection scenarios for Europe for the year 2050, detailed power system simulation at hourly time steps, and life cycle assessment of electricity in order to explore the influence of time on the greenhouse gas emissions associated with electric vehicle charging for representative days. We consider both average and short-term marginal emissions. We find that the mix of electricity generation technologies, and thus, also the emissions of charging, vary appreciably across the 24-h day. In our estimates for Europe for 2050, an assumed day-charging regime yields one-third-to-one-half lower average emissions than an assumed night-charging regime. This is owing to high fractions of solar PV in the electricity mix during daytime and more reliance on natural gas electricity in the late evening and night. The effect is stronger during summer months than during winter months, with day charging causing one-half-to-two-thirds lower emissions than night charging during summer. Also, when short-term marginal electricity is assumed, emissions tend to be lower with day charging because of contributions from nuclear electricity during the day. However, the results for short-term marginal electricity have high uncertainty. Overall, our results suggest a need for electric vehicle charging policies and emission assessments to take into consideration variations in electricity mixes and time profiles of vehicle charging over the 24-h day.

The Sustainable Development Goals (SDG) require increased hydropower electricity production to reach SDG 7. However, a balance between related positive synergies and negative trade-offs needs to be found. So far there has been a strong focus on the technical development potential (SDG 7), and the positive synergies of hydropower, for example in relation to SDG 13 (Climate change). However, hydropower can also cause, for instance, biodiversity impacts, leading to a negative biodiversity trade-off with SDG 6 (Clean water and sanitation) and SDG 15 (Life on land). Although conservation of biodiversity has been identified as a key parameter for sustainable development, global assessments accounting for site specific biodiversity trade-offs of hydropower sites are still lacking.To fill this research gap, we performed the first global and reservoir explicit assessment of terrestrial and aquatic biodiversity impacts of 2000 possible future hydropower reservoirs. We adapted the latest spatially explicit impact assessment methods available from the field of life cycle assessment, with a high-resolution and location-specific technical assessment of future economic hydropower potentials (Gernaat et al., Nature Energy 2017). More specially we collected site-specific environmental information from geographic information system databases to quantify potential reservoir-specific, net land occupation, net water consumption and methane emissions. Subsequently, we quantified the related terrestrial and aquatic biodiversity impact in units of potentially disappeared fraction of species (PDF).Our results show that future hydropower electricity production can have a spatially highly variable biodiversity impact (varying by orders of magnitude) which can interfere with SDG 6 and SDG 15. Furthermore, we show that careful selection of reservoirs on a macro level has a large potential to limit biodiversity impacts. Thus, sustainable hydropower development requires an assessment of potential biodiversity impacts. This in turn means, that if mitigating climate change for SDG 13 is the main motivation for increased hydropower production, as it can score favorable in studies comparing GHG emissions, it is likely that potential biodiversity impacts are overlooked. However, in order to move towards overall sustainability, taking biodiversity impacts into account next to climate change and other impacts, is of utmost importance.

Both fossil-fuel and non-fossil-fuel power technologies induce life-cycle greenhouse gas emissions, mainly due to their embodied energy requirements for construction and operation, and upstream CH4 emissions. Here, we integrate prospective life-cycle assessment with global integrated energy–economy–land-use–climate modelling to explore life-cycle emissions of future low-carbon power supply systems and implications for technology choice. Future per-unit life-cycle emissions differ substantially across technologies. For a climate protection scenario, we project life-cycle emissions from fossil fuel carbon capture and sequestration plants of 78–110 gCO2eq kWh−1, compared with 3.5–12 gCO2eq kWh−1 for nuclear, wind and solar power for 2050. Life-cycle emissions from hydropower and bioenergy are substantial (∼100 gCO2eq kWh−1), but highly uncertain. We find that cumulative emissions attributable to upscaling low-carbon power other than hydropower are small compared with direct sectoral fossil fuel emissions and the total carbon budget. Fully considering life-cycle greenhouse gas emissions has only modest effects on the scale and structure of power production in cost-optimal mitigation scenarios. All energy generation technologies emit greenhouse gases during their life cycle as a result of construction and operation. Pehl et al. integrate life-cycle assessment and energy modelling to analyse the emissions contributions of different technologies across their lifespan in future low-carbon power systems.

Variations in lignocellulosic feedstock composition can influence conversion performance of bioethanol production, but such effects are overlooked in several studies that rely on standard conversion factors. This study investigates the effects of seven lignocellulosic feedstocks (belonging to the categories energy crops, forest and agricultural residues) on mass, carbon, water and energy balances for biochemical bioethanol production, including a comparison of individual process step yields. We find that overall bioethanol yields vary considerably, ranging between 19.0 and 29.0%, 27.3 and 46.2%, and 19.0 and 31.0%, for energy and carbon efficiency, respectively. The highest yields are found for switchgrass, which has the largest carbohydrate content, and the lowest for forest residues (spruce). Feedstock composition also affects water and carbon balances. Overall, the type of biomass influences conversion performances, thereby calling for explicit representation of the effects of biomass types in technical, economic and environmental assessment studies of bioethanol production.

An in-depth review of five major integrated assessment models from an industrial ecology perspective reveals differences between the fields regarding the modelling of linkages in the industrial system. Technology-rich integrated assessment models (IAMs) address possible technology mixes and future costs of climate change mitigation by generating scenarios for the future industrial system. Industrial ecology (IE) focuses on the empirical analysis of this system. We conduct an in-depth review of five major IAMs from an IE perspective and reveal differences between the two fields regarding the modelling of linkages in the industrial system, focussing on AIM/CGE, GCAM, IMAGE, MESSAGE, and REMIND. IAMs ignore material cycles and recycling, incoherently describe the life-cycle impacts of technology, and miss linkages regarding buildings and infrastructure. Adding IE system linkages to IAMs adds new constraints and allows for studying new mitigation options, both of which may lead to more robust and policy-relevant mitigation scenarios.

Climate impacts of forest bioenergy result from a multitude of warming and cooling effects and vary by location and technology. While past bioenergy studies have analysed a limited number of climate-altering pollutants and activities, no studies have jointly addressed supply chain greenhouse gas emissions, biogenic CO2 fluxes, aerosols and albedo changes at high spatial and process detail. Here, we present a national-level climate impact analysis of stationary bioenergy systems in Norway based on wood-burning stoves and wood biomass-based district heating. We find that cooling aerosols and albedo offset 60–70% of total warming, leaving a net warming of 340 or 69 kg CO2e MWh−1 for stoves or district heating, respectively. Large variations are observed over locations for albedo, and over technology alternatives for aerosols. By demonstrating both notable magnitudes and complexities of different climate warming and cooling effects of forest bioenergy in Norway, our study emphasizes the need to consider multiple forcing agents in climate impact analysis of forest bioenergy. © The Author(s) 2018. Open Access. This article is licensed under a Creative Commons Attribution 4.0 International License.

Electricity transmission and distribution (T&D) plays a vital role in society by connecting electricity producers and consumers. We present a life cycle assessment case study of electricity delivery to consumers in Nord-Trøndelag county in Norway. We use a coherent framework for assessing electricity transfer via all the main segments of the Norwegian T&D system (local distribution, regional transmission and main national transmission grids). The assessment covers impacts associated with production, transport, and installation of components, power grid losses, and losses of sulphur hexafluoride. The results indicate that for electricity that is transmitted through the three main T&D grid segments, and assuming a Norwegian electricity mix when modelling the effects of power losses, the total carbon footprint of electricity T&D is 7.8 kg CO2-eq/MW h. Local distribution holds the largest share of this total (∼60%), while regional transmission and national transmission both make smaller but significant contributions (∼20% each). When classifying impacts as being attributable to either power grid losses or to other processes (e.g., materials and component manufacturing), both power losses and other processes contribute significantly to total impact potentials. Power losses are responsible for 30–43% of the combined electricity T&D impact potentials for climate change, particulate matter, smog-creation and acidification, 21–28% for toxicity and eutrophication, and 14% for metal depletion. For all categories except metal depletion, the relative importance of power losses increases appreciably if Nordic or particularly European electricity is assumed, however. Finally, we compare the environmental impacts of electricity T&D with that of electricity generation. The results of the comparison show that electricity T&D causes fewer impacts than electricity generation, but T&D impacts are not negligible; this is true regardless of what electricity mix is assumed when modelling power losses. © 2016. This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/

Background Forests and forest products can significantly contribute to climate change mitigation by stabilizing and even potentially decreasing the concentration of carbon dioxide (CO2) in the atmosphere. Harvested wood products (HWP) represent a common widespread and cost-efficient opportunity for negative emissions. After harvest, a significant fraction of the wood remains stored in HWPs for a period that can vary from some months to many decades, whereas atmospheric carbon (C) is immediately sequestered by vegetation re-growth. This temporal mismatch between oxidation of HWPs and C uptake by vegetation generates a net sink that lasts over time. The role of temporary carbon storage in forest products has been analysed and debated in the scientific literature, but detailed bottom-up studies mapping the fate of harvested materials and quantifying the associated emission profiles at national scales are rare. In this work, we quantify the net CO2 emissions and the temporary carbon storage in forest products in Norway, Sweden and Finland for the period 1960–2015, and investigate their correlation. We use a Chi square probability distribution to model the oxidation rate of C over time in HWPs, taking into consideration specific half-lives of each category of products. We model the forest regrowth and estimate the time-distributed C removal. We also integrate the specific HWP flows with an emission inventory database to quantify the associated life-cycle emissions of fossil CO2, CH4 and N2O. Results We find that assuming an instantaneous oxidation of HWPs would overestimate emissions of about 1.18 billion t CO2 (cumulative values for the three countries over the period 1960–2015).We also find that about 40 years after 1960, the starting year of our analysis, are sufficient to detect signs of negative emissions. The total amount of net CO2 emissions achieved in 2015 are about − 3.8 million t CO2, − 27.9 t CO2 and − 43.6 t CO2 in Norway, Sweden, and Finland, respectively. Conclusion We argue for a more explicit accounting of the actual emission rates from HWPs in carbon balance studies and climate impact analysis of forestry systems and products, and a more transparent inclusion of the potential of HWP as negative emissions in perspective studies and scenarios. Simply assuming that all harvested carbon is instantaneously oxidized can lead to large biases and ultimately overlook the benefits of negative emissions of HWPs. © The Author(s) 2018. This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/)

Cumulative energy demand (CED) estimates from life cycle assessments (LCAs) are increasingly used to determine energy return on investment (EROI), but the difference in indicators can lead to a misclassification of energy flows in the assessment. The core idea of EROI is to measure the relation of energy diverted from society to make energy available to society. CED, on the other hand, includes forms of energy that are not appropriated by society, such as fugitive methane emissions from oil wells as well as losses of heating value of coal during transport and storage. Such energy forms should be excluded from EROI; failure to do so leads to results that are inconsistent with the intention of EROI and potentially misleading. We demonstrate how this problem is at least partially rectifiable by adopting consistent energy accounting, but also note that among the energy flows not appropriated by society occurring in CED, not all flows can easily be removed. Further, we point to inconsistencies in heating value assumptions in a widely used database that have misled analysts. Finally, we argue that the differential weighting of primary energy forms in published CED-based EROI work is unsubstantiated and should be reconsidered. (c) 2014ElsevierLtd.Allrightsreserved. This is the authors' accepted and refereed manuscript to the article. Locked until 2017-01-15 due to copyright restrictions.

Climate impacts of forest bioenergy result from a multitude of warming and cooling effects and vary by location and technology. While past bioenergy studies have analysed a limited number of climate-altering pollutants and activities, no studies have jointly addressed supply chain greenhouse gas emissions, biogenic CO2 fluxes, aerosols and albedo changes at high spatial and process detail. Here, we present a national-level climate impact analysis of stationary bioenergy systems in Norway based on wood-burning stoves and wood biomass-based district heating. We find that cooling aerosols and albedo offset 60–70% of total warming, leaving a net warming of 340 or 69 kg CO2e MWh−1 for stoves or district heating, respectively. Large variations are observed over locations for albedo, and over technology alternatives for aerosols. By demonstrating both notable magnitudes and complexities of different climate warming and cooling effects of forest bioenergy in Norway, our study emphasizes the need to consider multiple forcing agents in climate impact analysis of forest bioenergy.

Decarbonization of electricity generation can support climate-change mitigation and presents an opportunity to address pollution resulting from fossil-fuel combustion. Generally, renewable technologies require higher initial investments in infrastructure than fossil-based power systems. To assess the tradeoffs of increased up-front emissions and reduced operational emissions, we present, to our knowledge, the first global, integrated life-cycle assessment (LCA) of long-term, wide-scale implementation of electricity generation from renewable sources (i.e., photovoltaic and solar thermal, wind, and hydropower) and of carbon dioxide capture and storage for fossil power generation. We compare emissions causing particulate matter exposure, freshwater ecotoxicity, freshwater eutrophication, and climate change for the climate-change-mitigation (BLUE Map) and business-as-usual (Baseline) scenarios of the International Energy Agency up to 2050. We use a vintage stock model to conduct an LCA of newly installed capacity year-by-year for each region, thus accounting for changes in the energy mix used to manufacture future power plants. Under the Baseline scenario, emissions of air and water pollutants more than double whereas the low-carbon technologies introduced in the BLUE Map scenario allow a doubling of electricity supply while stabilizing or even reducing pollution. Material requirements per unit generation for low-carbon technologies can be higher than for conventional fossil generation: 11–40 times more copper for photovoltaic systems and 6–14 times more iron for wind power plants. However, only two years of current global copper and one year of iron production will suffice to build a low-carbon energy system capable of supplying the world's electricity needs in 2050. © 2014 National Academy of Sciences

Stabilizing global temperature will require a shift to renewable or nuclear power from fossil power and the large-scale deployment of CO2 capture and storage (CCS) for remaining fossil fuel use. Non-climate co-benefits of low-carbon energy technologies, especially reduced mortalities from air pollution and decreased ecosystem damage, have been important arguments for policies to reduce CO2 emissions. Taking into account a wide range of environmental mechanisms and the complex interactions of the supply chains of different technologies, we conducted the first life cycle assessment of potential human health and ecological impacts of a global low-carbon electricity scenario. Our assessment indicates strong human health benefits of low-carbon electricity. For ecosystem quality, there is a significant trade-off between reduced pollution and climate impacts and potentially significant ecological impacts from land use associated with increased biopower utilization. Other renewables, nuclear power and CCS show clear ecological benefits, so that the climate mitigation scenario with a relatively low share of biopower has lower ecosystem impacts than the baseline scenario. Energy policy can maximize co-benefits by supporting other renewable and nuclear power and developing biomass supply from sources with low biodiversity impact. Original content from this work may be used under the terms of the Creative Commons Attribution 3.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.

The targeted transition towards an electricity system with low or even negative greenhouse gas emissions affords a chance to address other environmental concerns as well, but may potentially have to adjust to the limited availability of assorted non-fossil resources. Life cycle assessment (LCA) is widely recognized as a method appropriate to assess and compare product systems taking into account a wide range of environmental impacts. Yet, LCA could not inform the latest assessment of co-benefits and trade-offs of climate change mitigation by the Intergovernmental Panel on Climate Change due to the lack of comparative assessments of different electricity generation technologies addressing a wide range of environmental impacts and using a consistent set of methods. This paper contributes to filling this gap. A consistent set of life cycle inventories of a wide range of electricity generation technologies is assessed using the Recipe midpoint methods. The life-cycle inventory modeling addresses the production and deployment of the technologies in nine different regions. The analysis shows that even though low-carbon power requires a larger amount of metals than conventional fossil power, renewable and nuclear power leads to a reduction of a wide range of environmental impacts, while CO2 capture and storage leads to increased non-GHG impacts. Biomass has relatively modest co-benefits, if at all. The manufacturing of low-carbon technologies is important compared to their operation, indicating that it is important to choose the most desirable technologies from the outset. © 2017. This is the authors’ accepted and refereed manuscript to the article. LOCKED until 3.4.2019 due to copyright restrictions. This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/

China's remarkable economic growth in the last 3 decades has brought about big improvements in quality of life while simultaneously contributing to serious environmental problems. The aim of all economic activities is, ultimately, to provide the population with products and services. Analyzing environmental impacts of consumption can be valuable for illuminating underlying drivers for energy use and emissions in society. This study applies an environmentally extended input-output analysis to estimate household environmental impact (HEI) of urban Beijing households at different levels of development. The analysis covers direct and indirect energy use and emissions of carbon dioxide (CO(2)), sulfur dioxide (SO(2)), and nitrogen oxide (NO(x)). On the basis of observations of how HEI varies across income groups, prospects for near-future changes in HEI are discussed. Results indicate that in 2007, an urban resident in Beijing used, on average, 52 gigajoules of total primary energy supply. The corresponding annual emissions were 4.2 tonnes CO(2), 27 kilograms SO(2), and 17 kilograms NOx. Of this, only 18% to 34% was used or emitted by the households directly. While the overall expenditure elasticity of energy use is around 0.9, there is a higher elasticity of energy use associated with transport. The results suggest that significant growth in HEI can be expected in the near future, even with substantial energy efficiency improvements.

Purpose: This study aims to contribute to an improved understanding of the environmental implications of offshore power grid and wind power development pathways. To achieve this aim, we present two assessments. First, we investigate the impacts of a North Sea power grid enabling enhanced trade and integration of offshore wind power. Second, we assess the benefit of the North Sea grid and wind power through a comparison of scenarios for power generation in affected countries. Methods: The grid scenario explored in the first assessment is the most ambitious scenario of the Windspeed project, and is the result of cost minimization analysis using a transmission expansion planning model. We develop a hybrid life cycle inventory for array cables, HVDC links and substations. The functional unit is 1 kWh of electricity transmitted. The second assessment compares two different energy scenarios of Windspeed for the North Sea and surrounding countries. Here we utilize life cycle inventory for offshore grid components together with inventory for a catalog of power generation technologies from Ecoinvent, and couple these inventories with grid configurations and electricity mixes determined by the optimization procedure in Windspeed. Results and discussion: Developing, operating and dismantling the grid cause emissions of 2.5 g CO2-Eq per kWh electricity transmission, or 36 Mt CO2-Eq in total. HVDC cables are the major cause of environmental damage, causing for example half of total climate change effects. The next most important contributors are substations and array cabling used in offshore wind parks. Toxicity and eutrophication effects stem largely from leakages from disposed copper and iron mine tailings and overburden. Results from the comparison of two scenarios demonstrate a substantial environmental benefit from North Sea grid extension and the associated wind power development compared to an alternative generation of electricity from fossil fuels. Offshore grid and wind power, however, entail an increased use of metals and hence a higher metal depletion indicator. Conclusions: We present the first life cycle assessment of a large offshore power grid, using results of an energy planning model as input. HVDC links are the major cause of environmental damage. There are differences across impact categories with respect to which components or types of activities that are responsible for damage. North Sea grid and wind power are environmentally beneficial by an array of criteria if displacing fossil fuels, but cause substantial metal use. &nbsp

We develop and assess life cycle inventories of a conceptual offshore wind farm using a hybrid life cycle assessment (LCA) methodology. Special emphasis is placed on aspects of installation, operation, and maintenance, as these stages have been given only cursory consideration in previous LCAs. The results indicate that previous studies have underestimated the impacts caused by offshore operations and (though less important) exchange of parts. Offshore installation and maintenance activities cause 28% (10 g CO2-Eq/kWh) of total greenhouse gas emissions and 31–45% of total impact indicator values at the most (marine eutrophication, acidification, particulates, photochemical ozone). Transport and dumping of rock in installation phase and maintenance of wind turbines in use phase are major contributory activities. Manufacturing of spare parts is responsible for 6% (2 g CO2-Eq/kWh) of greenhouse gas emissions and up to 13% of total impact indicator values (freshwater ecotoxicity). Assumptions on lifetimes, work times for offshore activities and implementation of NOx abatement on vessels are shown to have a significant influence on results. Another source of uncertainty is assumed operating mode data for vessels determining fuel consumption rates. © American Chemical Society 2013. This is the authors accepted and refereed manuscript to the article.

We critically review present knowledge of the life cycle environmental impacts of wind power. We find that the current body of life cycle assessments (LCA) of wind power provides a fairly good overall understanding of fossil energy use and associated pollution; our survey of results that appear in existing literature give mean values (± standard deviation) of, e.g., 0.060 (±0.058) kWh energy used and 19 (±13) g CO2e emitted per kWh electricity, suggesting good environmental performance vis-à-vis fossil-based power. Total emissions of onshore and offshore wind farms are comparable. The bulk of emissions generally occur in the production of components; onshore, the wind turbine dominates, while offshore, the substructure becomes relatively more important. Strong positive effects of scale are present in the lower end of the turbine size spectrum, but there is no clear evidence for such effects for MW-sized units. We identify weaknesses and gaps in knowledge that future research may address. This includes poorly understood impacts in categories of toxicity and resource depletion, lack of empirical basis for assumptions about replacement of parts, and apparent lack of detailed considerations of offshore operations for wind farms in ocean waters. We argue that applications of the avoided burden method to model recycling benefits generally lack transparency and may be inconsistent. Assumed capacity factor values are generally higher than current mean realized values. Finally, we discuss the need for LCA research to move beyond unit-based assessments in order to address temporal aspects and the scale of impacts. (C) 2012 Elsevier Ltd. All rights reserved. This is the authors' accepted and refereed manuscript to the article.

Environmental implications of large-scale adoption of wind power : a scenario-based life cycle assessment (vol 6, 045102, 2011))