Global Warming Potential Impact Categories Research Articles

Life cycle assessment of waste management in rural areas in the transition period from mixed collection to source-separation

Rural solid waste management is essential for fulfilling sustainable development goals, especially in developing countries. However, quantitative study on this aspect has been little and far behind the urban areas. In this study, the environmental impacts of four typical rural solid waste management systems were quantified using life cycle assessment based on data from field investigations of five towns across four seasons. Sensitivity analysis was used to determine the most influential parameters. The results showed that landfilling mixed waste contributed the highest environmental impacts. By substituting landfilling with incineration, the environmental impacts (i.e., global warming potential, terrestrial acidification potential, fossil resource scarcity, freshwater ecotoxicity potential) dropped about 110%-900%. When shifting collection schemes to source separation, the environmental impacts also decreased by approximately 50%-200%. However, the environmental impacts of applying source separation to the existing management systems with mixed collection and disposal facilities of landfill or waste-to-energy (WTE) incineration are unclear and depend on the performance of decentralized composting and anaerobic digestion facilities, which need further investigations. Compared with urban cases, the landfill in rural areas emits higher greenhouse gas (GHG), and WTE incineration plants in rural areas have similar GHG emissions to WTE in urban areas. Besides, energy recovery was the most influential process in WTE systems and a 1% improvement on that would bring over 10% progress on global warming potential impact category. These findings can be useful for improving and developing rural domestic waste treatment in China and other developing countries.

Is durable environmentally sustainable? The durability of refrigerators assessed with energy mix varying towards energy transition

Sustainability and durability are not always synonyms when related to Energy Related Products. Europe has set goals to reduce the environmental impact due to the production of electricity. This paper accomplishes needs to investigate whether using a durable product for many years is more convenient, from an environmental perspective, than substituting the good with a new one. It assesses the environmental sustainability of durable products, taking the case of two single-door freestanding refrigerators used in Europe. In doing so the change in the composition of sources used in the production of electricity is considered. This is then compared with durability results, assuming the yearly energy consumption to be stable over time. The results highlight that introducing additional parameters that describe more accurately the real case can help in drafting a more precise description of reality, even though makes the use of full indexes mandatory. Water use and Mineral Resource Scarcity indicators there are clear trends, whose common thread is the use of simplified or extended durability index formula. The reduction of fossils and the decreased impact related to the consumption of energy make the weight of production and disposal phases heavier in the lifecycle impact distribution and increase the positive contribution of the durability index (Pn + En). For Global Warming Potential impact category (for which use phase retains at least 80% of the environmental impacts) there isn't any clear trend: it urges to describe energy grid mix variations or other factors according to realistic parameters. Future works should consider the consequences of the energy mix due to the geopolitical criticalities Europe is facing and introduce additional parameters that describe how the product performance change over time.

Life Cycle Assessment of Sensible, Latent and Thermochemical Thermal Energy Storage Systems for Climate Change Mitigation – A Systematic Review

Renewable energy sources coupled with thermal energy storage (TES) systems offer a better hope in mitigating climate change. But, in order to integrate TES systems into the grid, it is important to understand their environmental performances. Life cycle assessment (LCA) serves as a leading methodological tool for environmental decision-making processes that allows one to identify the critical areas of improvement in a product life cycle, and hence can be used effectively in climate change mitigation strategies. Due to the scarcity of review articles that provide useful information on the LCAs of TES systems, a total of 23 papers were reviewed in this study. These were reviewed under three categories: sensible heat storage (SHS) systems, latent heat storage (LHS) systems, and thermochemical heat storage (THS) systems. Further, the greenhouse gas (GHG) emissions arising from TES systems were evaluated, giving special attention on the global warming potential impact category. The production stage was found to be the major contributor to GWP in all three TES systems. Following this review study, it can be concluded that the environmental performance can be greatly enhanced through TES systems, due to significant reductions in GHG emissions. Keywords: LCA, thermal energy storage, sensible heat, latent heat, thermochemical heat, PCMs DOI: 10.7176/JETP/12-5-02 Publication date: November 30 th 2022

Life cycle assessment of residential buildings and scenarios for prolonged life span

This study deals with determination of the share of building materials impacts in whole building life cycle considering longer life span. Our aim is to investigate differences between widely used 50-year life span compared to100 and 150 years. Purpose of this study is thinking about aging residential building fond in Slovakia and their future. It is needs to be said that highest peak in building development occurred between 1955 till 1983 when prefabricated residential buildings were mostly made. These buildings take almost 38% share of all buildings finished till 2020 and youngest of them are almost 40 years old in 2022. It is needed to re-evaluate 50-year life span in all cases. Based on this situation this work focuses on residential buildings located in Slovak republic. For the assessment One Click LCA software was used, boundaries were set for cradle to grave. The functional unit was chosen 1 m2 of the total floor area in duration of determined life span. Results are presented for modelled scenarios which investigates changes in global warming potential impact category.

Comparison and analysis of product stage and service life uncertainties in life cycle assessment of building elements

Abstract Life cycle assessment (LCA) has the potential to inform building decisions from the planning process to conceptual design. As such, there is intrinsic uncertainty that needs to be explored further to allow for proper decisions to be made. These uncertainties may be related to parameter definition, such as life cycle inventory or model as service life definition. This paper aims to analyze the influence of two recognized sources of uncertainties in LCA of buildings: product stage uncertainties and uncertainties from SL during the use stage. The Monte Carlo simulation method is applied to conduct uncertainty analysis of the LCA results of four building elements, namely, external cement plaster, external clay brick wall, external painting and internal painting. The functional unit is 1 m2 of each building element. Three different building reference study periods are considered: 50, 120 and 500 years. A global warming potential impact category is chosen since it is one of the most significant indicators for climate change mitigation strategies. Results indicate that SL uncertainties are greater than product stage uncertainties for the four building elements analyzed. Furthermore, based on the findings from this study, distribution choice influences the uncertainty analysis results in Monte Carlo simulation. Standardizing modeling of SL in the LCA of buildings could guide building LCA practitioners and researchers and lead to more comparable results.

Life cycle assessment and economic analysis of the electric motorcycle in the city of Barcelona and the impact on air pollution

In this work, the evaluation of the life cycle of the service provided by a medium-power motorcycle in a Spanish urban environment was carried out, comparing two motorcycles, a battery electric vehicle (BEV) is compared with an internal combustion engine vehicle (ICEV). The economic study of the total costs of ownership is also carried out considering the environmental costs associated with each type of vehicle. A comprehensive inventory is compiled for both vehicles (motorcycles) that describes the most relevant components and includes two types of batteries for the BEV. A sensitivity analysis of the most impactful parameters is also considered.The results indicate that the ICEV contributes approximately 5 times more in the global warming potential impact category mainly due to the consumption of fossil fuels. The BEV also impacts some categories in the manufacturing stage, a fact that is strongly related to the battery. Sensitivity analysis indicates that the total distance travelled plays an important role, but the electricity mix is probably the most relevant factor in terms of climate change impact category. The economic analysis reported lower environmental externality costs for the BEV, making it more affordable than the ICEV and highlighting the benefit in terms of air pollution. The BEV is presented as a suitable option vehicle from environmental and economic point of view and one of the actors to accelerate the transition towards a more sustainable urban mobility model.

COMPARISON OF GLOBAL WARMING POTENTIAL-IMPACT ON THE HANDLING OF THE HAZARDOUS-SLUDGE FROM THE CENTRALIZED INDUSTRIAL-WASTEWATER TREATMENT PLANT

Aim: This study aimed to compare the secured landfill method and thermally sludge treatment through gasification, in order to determine their environmental impacts. Methodology and Results: The gate-to-gate LCA method was the implementation approach used to determine the, limits and assumptions to the actual condition. The experimental, theoretical mass balance calculation and secondary data of previous researches were used to carry out this study, with open-source openLCA software. In addition, the LCA was made up of four phases which include goal and scope definition, inventory analysis, impact assessment, and data interpretation. The simulation showed that the implementation of the thermal gasification process reduced the emission released to the atmosphere by lowering the hazardous sludge volume which is directly transported to the secured landfill. Conclusion, significance and impact study: Several assumptions and adjustments were made to the simulation results using the openLCA software, in the determined scope of study. Therefore, in conclusion, the thermal (gasification) treatment of hazardous sludge is further studied in connection with its implementation at the treatment plant. This was indicated by the acquisition of global warming potential impact category of 673 kg CO2 eq for direct disposal to secured landfill, which reduced to 424 kg CO2 eq during the implementation of thermal treatment. Conversely, there is a reduction in magnitude of impact by 37%.

Hazardous pollutants emissions and environmental impacts from fuelwood burned and synthetic fertilizers applied by tobacco growers in Pakistan

This study aimed to estimate hazardous and greenhouse gas (GHG) emissions and associated environmental impacts from fuelwood burning and synthetic fertilizer application by tobacco growers in Pakistan during the cropping year of 2014–2015. Primary data regarding fuelwood and synthetic fertilizers consumption were collected through surveys and interviews with tobacco growers in the Khyber Pakhtunkhwa (KP) and Punjab provinces of Pakistan. Annual fuelwood consumption data (t dm/y) were converted into harvested biomass (m3) using a general wood density value of 0.65 t dm/m3. For annual GHG estimations, methodology outlined by the Intergovernmental Panel on Climate Change (IPCC) was applied. The results revealed that fuelwood consumption varies from region to region and amounted to 99,268 t dm and 152,721 m3 during the cropping year 2014–2015. GHG emissions from fuelwood burned by tobacco curing barns are estimated as 160,245 tCO2, 705 tCH4, and 4.74 tN2O in 2014–15. Moreover, consolidated GHG emissions from fuelwood burning in tobacco curing barns in terms of tonne CO2-equivalent using global warming potential for 100-year time horizon is estimated to be 176,564 tCO2e during 2014–15. Similarly, annual nitrogenous fertilizers and urea consumption and consequent N2O and CO2 emissions were 117,223 and 41,084 kg and 347 and 30 tCO2e emissions, respectively. Furthermore, consolidated GHG emissions from synthetic fertilizers consumption in tobacco growing regions are estimated to be 377 tCO2e in 2014–15. Fuelwood harvesting and synthetic fertilizers application by the under study tobacco curing industry is a major cause of GHG emissions and contributes about 0.00094% of the Pakistan’s greenhouse gas emissions. The results of a life cycle impact assessment for different synthetic fertilizers applied to produce one kg of green tobacco revealed that NPK (nitrogen–phosphorus–potassium), ammonium nitrate, and urea production and application had the highest contributions to the abiotic depletion, acidification potential, eutrophication potential, and global warming potential impact categories. Therefore, it is imperative to take into account hazardous and GHG emissions mitigation strategies from fuelwood harvesting and synthetic fertilizers application by tobacco growers in Pakistan.

Quantifying carbon sequestration on sheep grazing land in Australia for life cycle assessment studies

The sheep industry has played an important role in Australia’s development and economy over the 220 years since European settlement and remains an important land use in Australia, occupying an estimated 85 million ha of continental land mass. Historically, deforestation was carried out in many sheep-rearing regions to promote pasture growth but this has not occurred within recent decades and many wool producers have invested in planting trees as well as preserving patches of remnant vegetation. Although the limitations of single environmental impact studies are recognised, this paper focuses on the contribution of carbon sequestration in trees and shrubs on sheep farms to the global warming potential impact category in life cycle assessment of wool. The analysis represents three major wool-producing zones of Australia. Based on default regional yields as applied in Australia’s National Inventory model, FullCAM, CO2 removals in planted exotic pines and mixed native species were estimated to be 5.0 and 3.0 t CO2 ha–1 year–1, respectively, for the Northern Tablelands of New South Wales in the ‘high-rainfall zone’ and 1.4 t CO2 ha–1 year–1 for mixed native species in the ‘sheep-wheat zone’ of Western Australia. Applying modified factors allowing for the higher measured growth rates in regions with rainfall >300 mm, gave values for native species reforestation of 4.4 and 2.0 t CO2 ha–1 year–1 for New South Wales and Western Australia, respectively. Sequestration was estimated to be 0.07 t CO2 ha–1 year–1 over 100 years for chenopod shrublands of the ‘pastoral zone’ of South Australia but this low rate is significant because of the extent of regeneration. Sequestration of soil organic carbon in improved permanent pastures in the New South Wales Northern Tablelands was evaluated to be highly uncertain but potentially significant over large areas of management. Improved data and consistent methodologies are needed for quantification of these benefits in life cycle assessment studies for wool and sheep meat, and additional impact categories, such as biodiversity, need to be included if the public and private benefits provided by good management of vegetation resources on farms are to be more fully recognised.

Life cycle assessment of pyrolysis–gasification as an emerging municipal solid waste treatment technology

Waste-to-energy technologies are considered as one of the key waste treatment technologies due to their energy and heat recovery efficiencies from the waste. A number of research studies were accomplished to understand the potential environmental burdens from emerging waste treatment technologies such as pyrolysis–gasification (PG). The aim of this study was to examine the PG of municipal solid waste (MSW) treatment process through a life cycle assessment (LCA) method. The study also includes a comparative LCA model of PG and incineration to identify the potential environmental burdens from the existing (incineration) and emerging (PG) waste treatment technologies. This study focused on ten environmental impact categories under two different scenarios, namely: (a) LCA model of PG and (b) comparative LCA model of PG and incineration. The scenario (a) showed that PG had significant environmental burdens in the aquatic eco-toxicity and the global warming potential impact categories. The comparative scenario (b) of PG and incineration of MSW showed that PG had comparatively lower potential environmental burdens in acidification, eutrophication, and aquatic eco-toxicity. Both LCA models showed that the environmental burdens were mainly caused by the volume of the thermal gas (emissions) produced from these two technologies and the final residue to disposal. Therefore, the results indicate that the efficiency and environmental burdens of the emerging technologies are dependent on the emissions and the production of final residue to the landfill.

Environmental assessment of urban water cycle on Mediterranean conditions by LCA approach

Urban water authorities in many countries are struggling to satisfy the increasing demand for both potable and non-potable water whilst also improving the environmental profile of the urban water system. The main goal of this study is to use the Life Cycle Assessment methodology to carry out an environmental analysis of every stage of the urban water cycle in Tarragona, a Mediterranean city of Spain (scenario I). These stages are: water abstraction, potable water treatment, intermediate pumping, distribution network, sewage collection and wastewater treatment. This study also proposes possible scenarios for improving the environmental performance reducing the high level of water stress resulting from increasing demand and limited resources: using reclaimed water (scenario II) and using desalination plants and reclaimed water to supply water during a drought (scenario III). Inventory analysis was performed using local operation data. In the current situation (scenario I) the main environmental impacts on urban water cycle were caused by 35.2% of distribution network, 20.5% of collection pumping and 13.8% of wastewater treatment plant for the Global Warming Potential impact category because these stages have high energy consumption. In Reclaimed water (scenario II), no significant improvement in indicators is observed, because the addition of environmental loads introduced by the tertiary treatment, except for the reduction in freshwater consumption due to the net water saving. In the drought scenario (scenario III), all impact categories have been increased from Scenario II e.g. 18% in Photochemical Oxidation, 21% in Eutrophication Potential, 30% Ozone Depletion Potential and Ecotoxicity Potential, 36% in Depletion of Abiotic Resources and Cumulative Energy Demand, 38% in Global Warming Potential and 42% in Acidification Potential.