Global Warming Potential Research Articles

In-vitro Evaluation of Solution Pressurised Metered Dose Inhaler Sprays with Low-GWP Propellants.

The transition from high Global Warming Potential (GWP) propellants such as HFA134a to low-GWP alternatives such as HFA152a and HFO1234ze(E) in pressurised metered dose inhalers (pMDIs) poses a number of challenges for inhaled pharmaceutical product development. Changes in chemicophysical properties will alter product performance, impacting in-vitro bioequivalence metrics. This study investigates those differences using equivalent pMDI hardware and formulations. Aerodynamic particle size distribution (APSD) measurements, laser diffraction and high-speed imaging were used to compare the performance of HFA134a, HFA152a and HFO1234ze(E) solution formulations of beclomethasone dipropionate. Propellant-only placebos, cosolvent-free solutions, and ethanol solutions at 8% and 15% w/w were investigated. HFA152a formulations had increased drug deposition on the actuator and throat while HFO1234ze(E) produced comparable APSD performance to HFA134a formulations. Plumes from HFA152a formulations spread more rapidly and were less stable and repeatable than those from HFA134a. HFO1234ze(E) plumes spread more slowly than HFA134a, but converged with HFA134a ex-mouthpiece. Differences between propellants were moderated by the addition of ethanol. Plume stability is a driver of differences between formulations in the near-orifice region. Shot-to-shot repeatability differences are more pronounced ex-mouthpiece, where mixing with ambient air is dominant. Modifications to low-GWP pMDI product actuator orifice and mouthpiece geometries may provide a route to improved in-vitro product bioequivalence relative to current pMDIs. Differences between formulations are modest and may be managed through a combination of formulation, orifice and mouthpiece geometry changes. These generic formulations provide a database of benchmark data against which the performance of low-GWP products may be compared.

Lack of harmonisation of greenhouse gases reporting standards and the methane emissions gap

Monitoring companies’ contributions to climate dynamics and their exposure to transition risks requires accurate measurements of their non-carbon dioxide greenhouse gas emissions (non-CO2 GHG). However, carbon accounting standards are not harmonised and allow for some discretion when converting emissions of different GHGs into CO2 equivalent units, the currency in which carbon footprints are expressed. Focusing on methane, we build counterfactual harmonised standards using the latest IPCC Global Warming Potential (GWP) values over 100 years and estimate a cumulative gap in reported methane emissions of 170MtCO2e ( ~6Tg) over a sample of 2864 companies. Changing the counterfactual from GWP100to GWP20, as recently codified in certain jurisdictions and initiatives, increases the cumulative gap to 3300MtCO2e ( ~40Tg). The gap only covers direct emissions and hence understates the extent of potential under-reporting across value chains. Overall, our study underscores the importance of global harmonisation of CO2-equivalence standards to coherently track corporate GHG emissions and their exposure to transition risks.

A Comparative Review of IG-541 System Use in Total Flooding Application for Energized Electrical Fire

Clean agent fire suppression systems are commonly used to protect areas containing valuable or critical equipment, especially in data centers and electrical substations, where traditional fire suppression methods are less effective or pose additional risks. This review evaluates the IG-541 fire suppression system as an alternative to halocarbon-based agents like HFC-227ea and FK-5-1-12, which are being phased out under environmental regulations, focusing on their application in energized electrical fires. IG-541 offers environmental advantages, including zero ozone depletion potential, no global warming potential, and negligible atmospheric lifetime, making it compliant with stringent environmental regulations. This review compares IG-541 with halocarbon agents across parameters such as extinguishing efficacy, safety considerations, environmental impacts, cost impacts, and system design considerations. Key findings underscore IG-541’s effectiveness in reducing fire damage without producing harmful by-products or exacerbating climate change. Furthermore, the study highlights the regulatory frameworks influencing the phase-out of halocarbon agents and the transition toward environmentally sustainable alternatives. While IG-541 emerges as a promising replacement for halocarbon agents, further exploration into its application in varied fire scenarios and energy-intensive environments is recommended to optimize its deployment.

Combined CH4, N2O, and CO2 Fluxes Reveal a Net Carbon Sink Across a Glacier‐Ocean Continuum

AbstractRapidly retreating marine‐terminating glaciers potentially release trapped greenhouse gases to the atmosphere. Here, we quantified water‐air CH4 and N2O fluxes across a glacier‐lagoon‐ocean continuum in Iceland. Surface water CH4 ranged from 690% supersaturation relative to atmospheric equilibrium near the glacier to 140% on the shelf. N2O was undersaturated (84 ± 21%) near the glacier front and approached equilibrium in coastal seawater. The glacial lagoon was a CH4 source to the atmosphere and N2O sink, while nearshore shelf waters were a weak source of both gases. The total shelf CH4 emissions to the atmosphere were one order of magnitude greater than the lateral freshwater dissolved CH4 exports from the lagoon. The strong regional marine CO2 sink exceeds the CO2‐equivalent global warming potentials of CH4 and N2O emissions to the atmosphere by one order of magnitude. Overall, the glacier‐lagoon‐shelf continuum remains a major carbon sink despite widespread CH4 emissions and variable N2O sink/source behavior.

Disparities in low-carbon concrete GWP at the metropolitan level in the United States

The specification of Global Warming Potential (GWP) targets for low-carbon concrete is essential to guide decarbonization efforts for the built environment. Yet specifying GWP targets by multi-state regions reduces the granularity needed to define GWP targets locally. To probe this paradigm, we analyze 39,536 Environmental Product Declarations (EPDs) and show that 85.3% are manufactured near a highly populated U.S. metropolitan. Our results demonstrate that low-carbon concrete specification targets can only be met in metropolitan areas with sufficient GWP data, such as New York City and Los Angeles, which account for 41% of EPDs and, hence, skew regional GWPs – preventing equitable and attainable low-carbon concrete specifications. The use of supplementary cementitious materials remains a pathway to reduce GWP. Additionally, local differences in transportation and manufacturing reveal new avenues to achieve low-carbon targets. These findings evince the need for concrete GWP specifications at the metropolitan level to meet national decarbonization goals.

Sustainable Design of a Tiny House: Using a Life Cycle Assessment Approach to Compare the Environmental Performance of Industrial and Earth-Based Building Systems

The increased concerns about climate change, diminishing natural resources, and environmental degradation call for deep research into new environmentally friendly building systems that use natural or recycled materials. The article presents an assessment of the environmental and climatic benefits associated with the construction of a tiny house made of quincha, a building system based on a wooden structure filled with locally sourced earth and straw. The tiny house is located in the Elqui Valley, in the Chilean region of Coquimbo, and it is designed to be compact, functional, comfortable, and efficient. The study uses a life cycle approach to assess the environmental impacts of building construction, maintenance, and end-of-life treatment, comparing the adopted quincha solution with four hypothetical scenarios using industrial, prefabricated, and/or synthetic construction materials currently adopted in the region. The thermal performance of all the analyzed solutions is also included in order to provide insights into the impact of the operational phase. This paper demonstrates that the quincha solution, in the face of lower thermal insulation compared to the other prefabricated solutions (the U-value of the quincha wall is 0.79 W/m2K while the U-value of the best prefabricated wall is 0.26 W/m2K), has higher thermal inertia (time lag (TL) and decrement factor (DF) are, respectively, 6.97 h and 0.60, while other systems have a TL below 4 h and DF higher than 0.81). For a quantitative environmental evaluation, the carbon footprint (global warming potential), water footprint, and embodied energy indicators are assessed through LCA, which takes into account the mass of the materials and their emission factors. The effectiveness of the quincha solution is also reflected in environmental terms; in fact, it is found to have the lowest carbon footprint (2635.47 kgCO2eq) and embodied energy (42.7 GJ) and the second-lowest water footprint (2303.7 m3). Moreover, carbon sequestration values, which are assessed by estimating the carbon contained in building systems using wood and straw, demonstrate that the quincha tiny house is the only solution that can theoretically reach carbon neutrality (with its carbon storage value at −5670.21 kgCO2eq).

CF3H production from the ozonolysis of HCFOs: E- and Z-CF3CH=CHCl

CF3H production from the ozonolysis of HCFOs: E- and Z-CF3CH=CHCl

Influences of BIM-LOD and Geographic-Scale Environmental Impact Factors on embodied emissions: The Norwegian context

Influences of BIM-LOD and Geographic-Scale Environmental Impact Factors on embodied emissions: The Norwegian context

Techno-economic analysis of chemical looping heat pumps based on the levelized cost of energy

Techno-economic analysis of chemical looping heat pumps based on the levelized cost of energy

Comprehensive assessment of straw returning with organic fertilizer on paddy ecosystems: A study based on greenhouse gas emissions, C/N sequestration, and risk health.

High greenhouse gas emissions and soil deterioration are caused by the overuse of chemical fertilizers. To improve soil quality and crop productivity, it is necessary to utilize fewer chemical fertilizers to achieve sustainable agriculture. Organic substitution is a scientific fertilization strategy that will benefit future agricultural productivity development, little is known about how it affects the heavy metal content and trace gas emissions in rice grains. A field experiment using straw return to the field (SRF), organic fertilizer application (OFA), and their combination (SRF/OFA) fertilization strategies. The results demonstrated that SRF, OFA, and SRF/OFA increased the yield by 19.40%, 22.39%, and 28.36% than the natural growth control group (NG). The OFA has the highest STN stock and SRF/OFA has the highest STN sequestration rate, while SRF achieved the highest SOC stock and sequestration rate. The OFA reduced CO2, CH4, and N2O emissions by 17.73%, 71.87%, and 86.06%, resulting in a minimum global warming potential and greenhouse gas intensity yield among these strategies. Cumulative seasonal CO2 and CH4 emissions were negatively correlated with soil paddy soil C/N and C/P (P<0.05). Moreover, Cu, Cd, and Pb contents in grain were reduced by 66.18%-70.31%, 35.45%-40.91%, and 76.62%-77.92%, respectively. The health risk evaluation revealed that all metals had a target hazard quotient of <1, except for NG. The hazard index (0.42-0.53), which measures the additive effects of contaminants, exceeded the threshold. The implementation of the organic alternative strategy can reduce the trend of increasing surface pollution, slow down the excessive utilization intensity of agricultural resources, and encourage the development of a greener, more sustainable agricultural way.

Transition toward circular economy in the agrifood seedling phase: A Life Cycle Assessment on tomato trays.

National and international guidelines call for greater environmental sustainability in agriculture through the introduction of the circular economy. Recent studies investigate the introduction of new technologies and methodologies in the field, however, few focus on initial stages at the plant nursery or the management of the involved materials, and none scientifically calculate their environmental impact. To fill this gap, this paper focuses on an Italian case study that quantifies the environmental impact of the traditional seed trays used worldwide for growing, transporting and transplanting tomato seedlings, proposing and evaluating two alternatives from a circular economy perspective. To do this, the Life Cycle Assessment (LCA) methodology was applied to the traditional and to two new reusable, recyclable, washable seed trays, comparing their entire life cycles. Primary data, provided by three manufacturers, two nurseries and four agricultural farms, were modelled using SimaPro software. Their environmental impact was calculated considering the potentials of global warming, eutrophication, acidification, abiotic depletion of elements and fossil fuels, ozone layer depletion, water scarcity and photochemical oxidation. Results show that, irrespective of the type of material used for the seed pots, the extraction and production phase of the materials is the most impactful in the life cycles. The proposed trays resulted more environmentally sustainable than the traditional non-reusable expanded polystyrene tray. The work also quantified the environmental benefit achieved with the weight reduction of the seed pots and their better handling by operators, which avoided breakages and losses. Furthermore, it is shown how the proposed reusable solutions can be greener, reducing the impacts up to a third in the case of global warming potential. In conclusion, the research offers viable alternatives that can be used in the market all over the world, diminishing the overall impact of the seedling and transplanting phases.

Performance and feasibility analysis of an integrated airlift microalgae photobioreactor for cultivation and pre-harvesting.

Microalgae technology is highly attractive in the realm of wastewater treatment and CO2 removal. However, during the cultivation of microalgae, the phenomenon of light attenuation intensifies with the increasing cell concentration, resulting in a decrement in microalgal growth rate. To maintain high light transmittance and growth rate of microalgae, this study introduces a two-step pre-harvesting process involving flocculation and filtration within an airlift photobioreactor. In this way, the growth performance of microalgae was bolstered by an improvement in light availability, which was increased 1.59 times by harvesting 30% of the microalgae biomass. Additionally, the microalgae productivity was increased 12.3%. By diluting the cationic starch concentration to 3gL-1, the harvesting efficiency approached levels comparable to those achieved through magnetic stirring, while filtration resulted in a 1.9-fold increase in final biomass concentration. Moreover, a comparative life-cycle assessment of three harvesting methods revealed that the flocculation-filtration method exhibited the lowest global warming potential of -0.09 CO2 eq, positioning it as a viable and low-carbon alternative for microalgae harvesting.

Performance, thermodynamic modelling, and global warming potential of low sodium-activated artificial granulated slag substituted with quartz and limestone fillers

Performance, thermodynamic modelling, and global warming potential of low sodium-activated artificial granulated slag substituted with quartz and limestone fillers

Sustainability assessment of succinic acid production from cyanobacteria.

This work performs techno-economic assessment (TEA) and cradle-to-gate life cycle assessment (LCA) for a cyanobacterial system producing succinic acid (SA). Experimental studies of cyanobacteria cultivation producing disodium succinate (Na2Succ) in culture were used to build a scaled-up process producing 100 tonnes/year of SA. High-temperature (HT) and low-temperature (LT) crystallization of SA (Process I) and purification using methanol addition (Process II) were considered for downstream separation. A combination of upstream experimental data, ecoinvent® 3.9 database, literature, and simulation data were used. ReCiPe 2016 impact assessment method was used. The production costs were INR 1,654/kg ($21.04/kg) and INR 1,501/kg ($19.09/kg) for processes I and II, respectively. Global warming potential (GWP) for processes I and II were 7.95 kg CO2-eq and 6.32 kg CO2-eq, respectively, for 1 kg of SA. 36% reduction in production cost and 52%-56% reduction in GWP was observed with succinate titer increase from 2 g/L to 5 g/L.

A Review on Evaporator Modification in VCR System for Performance Enhancement

Abstract: This Review focuses on the design and fabrication of an evaporator with multiple isolated chambers for a refrigerator. The aim is to enhance the efficiency and performance of the refrigeration system by employing an innovative evaporator design. The literature review includes studies on various refrigerants, refrigeration systems, and the integration of advanced technologies like phase change materials (PCM), thermoelectric generators (TEG), and thermal energy storage (TES). These studies highlight the importance of optimizing refrigerant selection, improving heat transfer mechanisms, and addressing environmental concerns related to global warming potential (GWP) and ozone depletion potential (ODP). The project seeks to develop an evaporator with multiple isolated chambers, which can potentially offer better temperature control, increased heat transfer efficiency, and reduced energy consumption. By combining insights from previous research with practical fabrication techniques, this review aims to contribute to the advancement of refrigeration technology, ensuring both energy efficiency and environmental sustainability

Analysis of Energy Use and Environmental Impacts of Pistachio (Pistacia vera L.) in Conventional and Bio-friendly Production Systems

Humankind and natural ecosystems are facing global changes. There is a clear influence of human activities due to the use of contaminant energies among other factors. Therefore, it is a priority to find clean energies with less environmental impacts coming from bio-friendly production systems. Therefore, the main aim of this research is to examine energy use patterns, greenhouse gas emission (CO2, N2O, and CH4) and life cycle assessment (LCA) in pistachio (Pistacia vera L.) production systems. As experimental plots, we selected one plantation located in the North Khorasan province of Iran. Data were collected from two pistachio orchards with conventional (CPS) and with bio-friendly production systems (BPS). In 2 seasonal years, from 2020 to 2021, a functional unit of 1000 kg pistachio was used. The results indicated that total energy consumption in the conventional pistachio production system reached 58,759.86 MJ ha−1 in comparison to bio-friendly pistachio production systems with 31,149.02 MJ ha−1, accounting for 36.0% of fertilizer energy, 26% of diesel energy, and 12.7% of electricity. The energy use efficiency for the CPS and BPS was respectively 0.38 and 0.73, and also energy productivity for CPS reached 0.01 kg MJ ha−1 and BPS 0.02 kg MJ ha−1. Results indicated that the direct energy for CPS was 19.6% and for BPS 39.03%, but indirect energy inputs for CPS and BPS registered 76.4 and 60.5%, respectively. It was found that the non-renewable form of energy input for CPS was 83.8% and for BPS just 57.6%. We conclude that chemicals (pesticides, fertilizers), fuel and electricity were the most important inputs for the pistachio production system, which also influenced total CO2, N2O and CH4 emissions due to chemical inputs for CPS. In CPS and BPS, the total global warming potential (GWP) was 2445.24 and 1507.99 kg CO2eq ha−1, respectively. Compared to CPS, the application of the BPS method reduces total damage to human health, ecosystems, and resources.

Environmental impact analysis of crop residue burning in Madhya Pradesh: A multivariate comparison across key crops.

This study quantified the environmental impacts of residue burning of major produced and burned crops in Madhya Pradesh, central India. The environmental impacts were quantified using Life Cycle Assessment (LCA) coupled with Monte Carlo simulation of 1000 iterations. Crop wise marginal impacts of the crops have been quantified using Multivariate regression model. The results showed that sugarcane and rice have the highest emissions in key impact categories, such as particulate matter formation (PMF) and global warming potential (GWP), whereas wheat and maize exhibit comparatively lower impacts. The combustion of residues significantly increases marine eutrophication (MEUT), agricultural land use (ALU), terrestrial acidification (TEAF) and GWP. Each kilogram of burned residue results in an increase of 21% in MEUT, 0.05% in ALU, 0.046% in TEAF and 0.028% in GWP, intensifying climate change. The results underscore the immediate necessity for specialized residue management strategies for sugarcane and rice crops. It is advisable to utilize sustainable alternatives such as composting or biochar production to mitigate emissions and enhance soil health, thereby addressing environmental and human health issues.

Managing life cycle impacts of poly(3-hydroxyoctanoate)-based nanocomposites intended for biomedical and packaging applications.

The environmental pollution caused by post-consumer plastics and the associated health risks necessitate comprehensive life-cycle analyses of these materials, mainly focusing on their end-of-life impacts. This study presents an in-depth evaluation of the environmental implications of producing nanocomposites using poly(3-hydroxyoctanoate) (P(3HO)), a biodegradable and biocompatible polymer that holds great promise as an alternative to traditional plastics, in combination with calcium-, and zinc-based double-layered hydroxides (LDH) modified with the antioxidant α-tocopherol. Utilising the ReCiPe impact assessment method, we identified critical environmental impact categories, including fine particle formation, global warming potential, and toxicity. The analysis revealed that the biosynthesis of P(3HO) is the primary contributor to environmental impact, with electricity consumption accounting for approximately 95% of the overall effect. Purification processes significantly increase environmental impact, mainly due to the extra electricity used for freezing, centrifugation and evaporation. The preparation of nanoparticles contributes to the overall environmental impact, but its scale is reasonably differentiated and spans from 0,3% for Ca/Al nanoparticles to 9.9% for Zn/Al-toc variants, respectively. Although producing these eco-friendly polymers involves significant energy consumption, they present a viable long-term alternative to petroleum-based polymers. Specific life cycle management decisions, like recovering substrates, using renewable energy sources, or gaining overall process improvement, could bring significant environmental benefits. Investigated materials show substantial potential in biomedical coatings and active packaging applications.

Paddy–Upland Rotation Improves Rice Growth and Reduces Greenhouse Gas Emissions in Winter Paddy Fields

From May 2019 to May 2022, a field experiment was conducted to clarify the effects of paddy–upland rotations on rice yield and greenhouse gas emissions in winter paddy fields. Four types of rotation pattern, rice–oilseed rape, rice–radish, rice–faba bean, and rice–fallow (flooded), were investigated and the N2O, CH4, and CO2 emissions in situ and rice yield were determined. The results showed that the paddy–upland rotation mode required fertilization during the winter cropping season. Compared with the rice–fallow (flooded) mode, the flux rate and annual cumulative emissions of N2O were significantly higher in the paddy–upland rotation modes. The rice–radish mode had the highest flux rate and annual cumulative emissions of N2O. When the soil in each paddy–upland rotation mode was exposed to air in winter, the soil redox potential increased and reducing substances were oxidized. Compared with the rice–fallow (flooded) mode, the flux rate and annual cumulative emissions of CH4 significantly decreased in the paddy–upland rotation modes, with the rice–radish mode producing the lowest flux rate and annual cumulative emissions of CH4. Fertilization and crop planting were conducted in winter, and the soil moisture was low. Compared with the rice–fallow (flooded) mode, the flux rate of CO2 of the paddy–upland rotation modes increased significantly. The flux rate of CO2 in the rice–oilseed rape mode was the highest. Furthermore, the N2O and CH4 emissions produced during the rice season and annually were significantly positively correlated with those in the winter season, indicating that the winter season had a significant effect on greenhouse gas emissions from winter paddy fields. Because of the significantly higher annual cumulative emissions of CH4 and the significantly lower rice yield in the rice–fallow (flooded) mode than in the paddy–upland rotation modes, this mode’s global warming potential (GWP) and greenhouse gas intensity (GHGI) during the rice season are significantly higher than those of the paddy–upland rotation modes.

Environmental Assessment of Hybrid Waste-to-Energy System in Ghana

Waste management in most parts of Africa is characterized by the disposal of mixed waste in unengineered landfills. The aim of this study is to assess the environmental impact of mixed waste received at a waste-to-energy plant in Ghana relative to the current model of landfilling. A Life Cycle Assessment was conducted using OpenLCA software version 2.3.1 based on the ReCiPe Midpoint method. For landfilling, LandGEM software version 3.03 was used. The results indicate that waste-to-energy has the potential to provide carbon savings of 3.52 tCO2eq/ton of waste treated compared to landfilling. Pyrolysis is observed to have high avoided burden across all impact categories, with the lowest Global Warming Potential of −2.3 kgCO2eq. Anaerobic digestion shows a near neutral environmental impact with the highest value of 47.56 kg 1,4DCB for Terrestrial Ecotoxicity, while Refuse-Derived Fuel and segregation processes show low environmental burdens. The net avoided burden is highest for global warming and non-carcinogenic human toxicity potential. Overall, the hybrid waste-to-energy model is concluded to be an environmentally preferred waste management option compared to conventional landfilling methods, and we recommend that decision-makers facilitate investments into it. It is also recommended for the development of local inventories and databases to encourage more country-specific environmental impact studies and to reduce uncertainty.