Tons Of CO2-eq Research Articles

The Issues of Carbon Pricing in the Russian Federation: The Local and International Perspectives Under the Cost Approach and the Role of Afforestation Projects

This paper discusses the role of afforestation projects and other climate technologies in the green agenda for Russia and aims to justify the anchoring of jurisdictional carbon pricing in the cost approach to valuation, specifically, with reference to the cost economics for afforestation projects given their centrality to the agenda. Through that, and due to the inchoate state of carbon pricing in the study jurisdiction, this paper aims to advance price discovery for national carbon credits in both compliance and voluntary schemes. The cost approach framework, moderated by international market comparisons, indicates the fair price of carbon in Russian jurisdiction at the level of USD 20–25 per tonne of CO2-eq, which is close to the global median but is more than double the amount of carbon levies set under the Sakhalin GHG quota experiment. It is argued that unless such a fair price for carbon is set in the country, the national carbon credits market will not achieve viable growth, nor will sustainable development be advanced, and funds for it be adequately collected. This represents a relevant contribution to the literature on the development of the national carbon credit markets.

Horticultural Postharvest Loss’ and Its Socio-Economic and Environmental Impacts

Food losses and waste (FLW) have multidimensional environmental, social, and economic impacts, and avoidance efforts may yield better environmental gains than recovery. Horticulture has the highest FLW (≈50% of production loss), representing 38% of total global FLW. The primary data were collected from 343 grape farmers and middlemen in Egypt, and the life cycle assessment (LCA) methodology and the Category Method (C-Method) have been employed to estimate the percentage of Postharvest Losses (PHL) and its socio-economic and environmental effects across the supply chain (SC). Empirical findings show average PHL percentages of 10.06%, 5.82%, 6.53%, and 7.06% for growers, rural traders, wholesalers, and retailers. The total arable land, water, and energy consumed to grow this lost food are estimated at around 23 thousand hectares, 158 million m³, and 3.16 billion MJ of fossil energy (96.9 million liters of petrol), besides other agricultural inputs. This costs the economy of Egypt about $203.5 million yearly and emits 145 million tons of CO2eq. These findings highlight the significant role of cooperative marketing, shorter supply chains, and access to cold shipping, handling, and storage services to sustain product quality. Furthermore, agricultural education and extension are necessary to disseminate the best postharvest practices to increase stakeholders' knowledge and sustainably enhance SC actors' skills for using limited resources. These interventions require intensive public-private investment to incentivize small stakeholders to mitigate PHLs, accelerate food system transformation, and achieve sustainable production and consumption patterns.

Climate change impacts of municipal water sector and mitigation pathways: A national scale analysis and perspectives to carbon neutrality.

The growing concern on global warming has pushed to set ambitious targets of carbon neutrality or net zero at the water sector. Meanwhile, poor data availability has been reported to restrict the national assessment of climate impacts and mitigation strategies in water sector. In national greenhouse gas (GHG) inventories, water sector is embedded in other sectors' emissions making it difficult to monitor separately. This study presents a national scale evaluation of climate change impacts for water sector in Finland based on life cycle analysis (LCA). In addition, the effectiveness of currently available emission reduction measures is evaluated by scenario analysis until the year 2035. According to the results, the life cycle climate change impacts from the Finnish municipal water sector were 0,67 (0,46-0,88) million tonnes CO2-eq./year (142.8 (98.9-187.1) kg CO2-eq./person/year). Drinking water services accounted for 12.5-13.9 % and wastewater services 86.1-87.4 % of the total emissions. With currently feasible emission reduction measures, the climate change impacts could be reduced approximately 14-30 % in total by 2035. The aim of carbon neutrality in the water sector was found to be unrealistic to achieve with existing and currently feasible measures for Finland and thus significant new emission mitigation measures are needed. The vague definition of carbon neutrality and system boundary of water sector as well as the uncertainties related to the assessment of direct emissions, undermine the credibility of the ambitiously set target. Prioritizing emission offsets to reach the target may inadvertently lead to unintended negative consequences due to the limitations and incompleteness of offset methods.

Life Cycle Assessment of End-of-Life Tire Disposal Methods and Potential Integration of Recycled Crumb Rubber in Cement Composites

Globally, 1.5 billion annual tire outputs generate a substantial volume of end-of-life tires (ELTs), creating significant environmental challenges. Despite increased recovery rates, ELT management costs in Europe underscore the need for proactive strategies to mitigate environmental and health risks. This study comprehensively evaluates the environmental impact of disposal methods, including landfilling, incineration, and crumb rubber production, using Life Cycle Assessment (LCA) via the OpenLCA software 2.0.2. While incineration is sometimes identified as a disposal method, unprocessed scrap tires have potential applications in civil engineering that can better align with sustainability goals. Detailed ELT composition analysis reveals significant recycling potential, with car and truck tires containing 10–20% steel fiber content, less than 1–8% textile fibers, and approximately 80% natural and synthetic rubber content. Recycling 1 ton of ELTs saves an estimated 1.4–1.6 tons of CO2 Eq. compared to incineration. Mechanical recycling and application of recycled crumb rubber in concrete show significant environmental advantages, reducing mass density by approximately 55% and enhancing ductility by up to 40%, according to material testing results. These properties make crumb rubber particularly suitable for acoustic and resilient applications. Additionally, its elasticity and durability offer effective solutions for shoreline reinforcement, mitigating erosion and providing stability during flooding events. When used as a replacement for river sand in cement composites, crumb rubber contributes to a 24.06% reduction in CO2 emissions, highlighting its potential for environmentally friendly construction.

Modelling long-term greenhouse gas mitigation pathways for Mongolia

Abstract Mongolia’s faces substantial challenges to reduce its Greenhouse Gas (GHG) emissions due to a reliance on coal to meet electricity, heat and other energy demand and large livestock emissions. Despite this, Mongolia has committed to reduce GHG emissions by 22.7% in 2030 compared to a baseline emission scenario. Greenhouse gas mitigation assessments for Mongolia have focussed on actions to achieve emission reductions by 2030, but not on the potential for further reduction over the longer-term. This study addresses this gap through the development of long-term (2050) GHG emission pathways for Mongolia. From a technical mitigation potential perspective, these pathways aim to inform what level of GHG reduction targets Mongolia could commit to for the period after its current target expires. Greenhouse gas emissions are quantified for historic years (2010-2019) for all major GHG emitting source sectors, and projected to 2050 based on the population and socioeconomic development outlined in Mongolia’s Sustainable Development Vision 2050. Finally, mitigation scenarios that model implementation of 49 specific mitigation measures are developed, to quantify their emission reduction potential. Without mitigation, GHG emissions were estimated to increase by 67% and 139% in 2030 and 2050, respectively, compared to 2019 levels (39 million tonnes CO2-eq emissions). Implementation of the 49 mitigation measures could reduce GHG emissions by 40% in 2050 compared to the baseline. This study highlights that post-2030, Mongolia could increase its climate change mitigation ambition. Renewable Electricity generation, and energy efficiency were the measures that could achieve the majority of these additional emission reductions. However, despite the achieve emission reductions in excess of those within current commitments, there remains a substantial gap between the emission reduction potential of technically feasible measures currently being considered in Mongolia’s climate change mitigation planning, and full decarbonisation.

Integrated Energy and Environmental Modeling to Design Cost-Effective Building Solutions at a Regional Level

This study introduces a computationally efficient urban building energy model (UBEM) to assess decarbonization strategies for the residential sector at the regional level. The model considers a range of inputs, including building characteristics, climate data, technology penetration, and occupant behavior. The model provides an economic analysis associating emission reduction potential with economic returns through an abatement cost curve, which is critical to designing cost-effective solutions. The model was validated at its full scale in Portugal, using actual consumption data from all municipalities. Key findings showed that lighting upgrades (100% LEDs) are the most cost-effective measure, offering the lowest abatement cost (−521 EUR/tonCO2eq) and a low discounted payback period of 2 years, while heat pumps for water heating provide the highest emission reduction potential, with an annual reduction of 863 tonnes of CO2eq annually, equivalent to a 20% reduction in national emissions. Additionally, behavioral measures achieved an annual reduction of 147 tonnes of CO2eq. The analysis further reveals that, while some measures might have a negative abatement cost at the national level, their economic viability varies locally, with certain municipalities incurring positive abatement costs, highlighting how local context affects the economic viability of decarbonization strategies.

Determining the efficiency of local heat recycling wastewater based on a heat exchanger

RELEVANCE. The authors research the potential energy, economic and environmental effects of using local heat recovery from wastewater generated in showers. At the moment in Russia, almost all household wastewater is disposed of in sewer networks without the beneficial use of the heat that they possess. It is important to determine the effect of implementing this method of heat recovery, to identify and analyze the problems that prevent this from being done.THE PURPOSE. The purpose of the work is to determine the potential effect of using local heat recovery from wastewater generated in showers.METHODS. Based on a verified mathematical model of the heat exchanger, the energy effect from the individual use of the shower room is determined. A number of assumptions are applied to the heat consumption structure of an individual building and, based on available data on the average annual heat consumption of residential buildings in Moscow, the economic and environmental effect of energy-saving measures is calculated.RESULTS. Relative savings within the annual heat consumption of a building with a decentralized and centralized hot water supply system were 5,3% and 3,1%, respectively (64 and 37 GCal). Fuel economy amounted to: 9145 toe and 5227 toe for a building with a decentralized and centralized hot water supply system, respectively (14,5 and 8,5 thousand tons of CO2-eq). The payback period for energy-saving measures for the case of a decentralized hot water system based on an instantaneous electric water heater was 1,5 years.CONCLUSION. Local waste heat recovery makes it possible to obtain a significant energy and environmental effect within any locality, but at the moment there are no measures to support consumers implementing energy-saving measures. Currently, this method of heat recovery is of interest only to those consumers whose source of thermal energy for the needs of hot water supply is electricity.

Life Cycle Comparative Assessment of Polyethylene Terephthalate (PET) Plastic Bottles: A Case Study of Drinking Bottled Water in Ramathibodi Hospital, Thailand

In the current context where all sectors aim to promote sustainable development, hospitals, as large organizations with significant human interactions, face challenges in managing not only medical waste but also general waste such as water bottles. Improper management of these wastes can lead to environmental problems and high disposal costs. This study performed a life cycle assessment (LCA) of regular (petroleum-based) and alternative (bio-based) polyethylene terephthalate (PET) bottles used in Ramathibodi Hospital, Thailand, to identify effective strategies for mitigating environmental impacts. The assessment was divided into three scenarios: label-free bottles, bio-based bottles, and 100% recycling. The results indicate that using label-free bottles instead of conventional ones merely reduces environmental impacts by 2%. Transitioning to 30% and 100% bio-based PET can decrease greenhouse gas (GHG) emissions by 7 and 13 tons of CO2 eq per year, respectively. Currently, the hospital's PET bottles contribute 56.2 tons of CO2 eq annually. Health impacts associated with conventional PET bottles amount to 11.70 disability-adjusted life years (DALYs), a comprehensive measure that includes both mortality and morbidity. Meanwhile, 30% and 100% bio-based bottles reduce this to 7.35 and 4.87 DALYs, respectively. Achieving 100% recyclability in bottle management can cut GHG emissions from disposal processes by up to 90%. Moreover, combining the use of 100% bio-based PET bottles with 100% recycling can lower GHG emissions by up to 40% compared to current practices. These findings highlight the potential for significant environmental and health benefits through improved bottled water management strategies in hospitals.

Benefits and challenges in deployment of low global warming potential R290 refrigerant for room air conditioning equipment in California

High global warming potential gases (“high GWP”) are the fastest growing sector of greenhouse gas emissions in the world and in California and are primarily used as refrigerant gases in refrigeration and cooling equipment. Hydrofluorocarbons (HFCs) refrigerants are the dominant type of high GWP gases with GWP values thousands of times larger than CO2 on a 100-year timescale. Refrigerant-grade propane (“R290”) has a very low GWP (GWP = 3.3) with good thermodynamic properties and good cooling equipment performance but the flammability of any leaked refrigerant makes equipment design, handling, and maintenance critical factors to manage. This paper focuses on the potential climate benefits and costs of transitioning to R290 refrigerant in small room air conditioning (AC) units, specifically window AC, packaged terminal AC/heat pumps (PTAC/PTHP), and mini-split heat pumps. Overall climate impact for a transition to all three types of air conditioning units in the 2022–2051 timeframe is found to be from 15 to 64 million metric tons of greenhouse gas (GHG) savings in California with a cost of saved CO2eq that ranges from $14.50 per ton of CO2eq saved to −$50.30 per ton of CO2eq saved (net savings) depending on whether the baseline refrigerant is R32 or R410A and depending on the relative energy efficiency for R290 units compared to baseline units.

Analysis of the Impact of Biomass/Water Ratio, Particle Size, Stirring, and Catalysts on the Production of Chemical Platforms and Biochar in the Hydrothermal Valorization of Coffee Cherry Waste

In Colombia alone, 12.6 million bags of green coffee are produced, but at the same time, 784,000 tons of waste biomass are dumped in open fields, of which only 5% is recovered or used, and 10 million tonnes of coffee emit 28.6 million tonnes of CO2 eq annually. This presents a worrying dilemma, and the need to develop a technology to transform the waste into usable products is increasing. As a response to this, the valorization of coffee waste was explored through the production of biochar and platform chemicals by implementing a set of hydrothermal experiments with different biomass/water ratios (1:5, 1:10, 1:20, 1:40), particle sizes (0.5, 1, 2, 5 mm), stirring rates (5000 and 8000 rpm), and catalysts (H2SO4, NaHCO3 and CH3COOH) at 180, 220, and 260 °C in a batch reactor with autogenous pressure. Notably, the smaller B:W ratios of 1:20 and 1:40, as well as smaller particle sizes of 0.5 and 1 mm, yielded higher amounts of platform chemicals, while stirring showed minimal influence. CH3COOH significantly enhanced the process compared to other catalysts. The biochar was characterized as anthracite, and this obtaining of coal-like materials from biomass itself represents a remarkable feat. Said anthracite presented little to no variation in physical parameters, while catalysts induced functionalization. By optimizing factors like B:W ratio, particle size, and catalyst application, valuable insights have been gained into enhancing the yield of platform chemicals and quality of biochar from coffee waste. The findings not only contribute to sustainable waste management practices but also highlight the importance of exploring innovative solutions for utilizing agricultural by-products effectively.

Impact of renewables on the Peruvian electricity system

Peru is committed by international agreements such as the Paris Agreement and the UN 2030 Agenda for Sustainable Development to reduce its Green House Gas (GHG) emissions. Although Peru began promoting power plant projects based on renewable energies in 2008, the institutional impulse seems to have ceased today. Nonetheless, adopting renewable energy sources not only aids in fulfilling these commitments but also reduces electricity prices, fostering a more competitive economy. This study aims to provide a thorough analysis and evaluation of the impact that integrating Non-Conventional Renewable Energy Resources (NCRER) has on Peru's wholesale electricity market. Specifically, it focuses on the net total savings for the system, calculated as the difference between the reduction in energy costs traded and the cost of the renewable premium. To reach that goal a simplified yet analytical tool has been developed based on a multivariable regression of the real data of the market. The volume of natural gas not consumed and the volume of GHG emissions avoided will also be evaluated. The results show that based on the 2021 scenario, a NCRER share of 28.26 % would lead to a net saving for the final users of 316.04 MUSD in the annual energy traded in the market. The reduction of conventional thermal generation prevents the annual burning of 2.04 normal km3 of natural gas and the emission of 4.99 million tons of CO2-eq. To the authors' knowledge, this is the first time that the impact of NCRER production in the Peruvian electricity system has been quantitatively evaluated.

(Invited) Achieving Robustness and Economic Viability in CO2 Electrolysis Scale-up: Key Results from RenewCO2

RenewCO2 is commercializing processes to convert carbon emissions from chemical manufacturing, which contributes 274 million metric tons of CO2eq annually in the U.S. alone. Our pioneering electrocatalytic Carbon Utilization Technology (eCUT) is adept at upcycling CO2 from hard-to-decarbonize industrial sources. By synthesizing commodity chemicals from CO2 emissions, eCUT promises high energy efficiency while producing carbon-negative materials. The critical innovation of RenewCO2’s eCUT process is deploying catalysts designed with readily available metals, optimizing the process to reduce CO2 into multi-carbon chemicals selectively with impressive energy efficiency.RenewCO2 has significantly advanced CO2 electrolyzer scale-up, focusing on demonstrating process robustness and economic feasibility. Targeting liquid products such as monomers (glycols), RenewCO2 has demonstrated cost-advantaged process economics compared to the incumbent petrochemical and bio-derived routes. We present detailed findings on the enhanced performance of our proprietary catalysts, which have shown remarkable endurance under prolonged operational conditions (1000 h of operation) in a scaled-up stack containing five 500 cm2 electrodes. The RenewCO2 team has demonstrated consistent electrolyzer performance with minimal degradation over extended periods. We also delve into improvements in energy efficiency, showcasing how these enhancements contribute to the overall process economics.The purification process is crucial in making carbon-negative materials from CO2 that do not require a green premium. In this regard, RenewCO2 has achieved remarkable progress in demonstrating a highly energy-efficient product purification. In collaboration with Argonne National Lab, we have developed an advanced electrochemical separation method that removes ionic species from the products to comply with strict industrial standards and increase their market value. A key development in this area is our innovative approach to electrodeionization, which combines ion-exchange membranes with electrically active media. This method exhibits low energy consumption, robustness, and simple operation. These advancements in the purification process are integral to our system’s overall efficiency and are pivotal in our pursuit of creating economically viable and sustainable electrochemical manufacturing solutions.On the economic front, we provide an in-depth analysis of the cost implications of scaling up. This includes a breakdown of the capital and operational costs, along with a comparative analysis with existing technologies. We discuss the main factors contributing to product cost and strategies to minimize them, such as the integration of low-cost materials and judicious choice of operating conditions.Our aim is to provide a transparent and comprehensive overview of the challenges and the state-of-the-art in scaling up CO2 electrolysis to liquid products, offering valuable insights for the scientific community and stakeholders in the field.

Alternative uses for urban autumn tree leaves: A case study in profitability and greenhouse gas emissions for the city of Berlin

Autumn tree leaves collect as waste on many city streets every year. In the city of Berlin, they are usually collected and transported for composting as their final treatment, which emits greenhouse gases (GHG) into the atmosphere. This study assesses alternative end uses of autumn tree leaves in order explore the potential of reducing GHG emissions while producing electric energy from residual biomass. It uses a combination of partial life-cycle assessments and net present value (NPV) to explore the different net GHG emissions and economic benefits of using autumn tree leaves for the following scenarios: anaerobic digestion (biogas), gasification, and co-firing. Assuming the use of 36,000 tonnes of leaves per year, co-firing in existing power plants shows the highest NPV, of between 10.3 million and 12.1 million euros for a 10-year lifetime, in line with the phase-out of coal combustion in Germany. It also results in the lowest net GHG emissions, with savings of between 252,000 and 144,000 tonnes of CO2eq. Gasification in new plants resulted in similar NPVs, estimated at between 9.80 and 9.86 million euros over a 20-year investment horizon, but lower emissions savings of 178,000 to 127,000 tonnes of CO2eq. Biogas production showed high emissions savings of 204,000 to 203,000 tonnes of CO2eq, but a much lower NPV of between 2.3 and 2.5 million euros. Composting was the only scenario with positive net GHG emissions. The amount of energy retrieved from the conversion technologies and the electrical tariff applied were the main drivers of these results. Other aspects that can shape the results include the availability of infrastructure and transport distances. The results are highly sensitive in both cases to the dryness of the leaves, while electricity tariffs influenced the economic performance considerably.

Assessment of Corporate Carbon Footprint and Energy Analysis of Transformer Industry

Transformers are primarily key components in power transmission and distribution systems. In the electrical industry, transformers are becoming increasingly important to increase energy efficiency and reduce environmental impact. In the process from the production to the use of transformers, various strategies and technologies are adopted to reduce the carbon footprint. To achieve decarbonization targets and a future with sustainable energy, ongoing efforts to reduce the carbon footprint of transformers need to continue. Therefore, this study aims to calculate the carbon footprint (CF) of Beta Energy in the Adana Province of Türkiye. A comprehensive inventory is being created to determine and monitor the greenhouse gas emissions of Beta Energy, a transformer manufacturer. This inventory includes direct and indirect greenhouse gas emissions from all of the company’s activities. The findings show that in 2023, the total CF of Beta Energy is equal to 1,799,482.72 tons of CO2-eq and considering the total of 6044 transformers sold in 2023, results in 297 tons of CO2-eq/transformer per product. The results show that the transformer manufacturing industry has a high carbon footprint because it is an energy-intensive process. The areas where the most carbon emissions occur in transformer production are revealed by CF hot spot analysis in this study. To minimize both current and future greenhouse gas emissions during transformer production, the measures to be taken during the R&D, production, transportation, and service stages are revealed. This study aims to establish a foundation for Beta Energy’s efforts to reduce greenhouse gas emissions by managing them effectively.

Optimizing waste leachate treatment for environmental and economic sustainability: Insights from a bottom-up study of over 300 cities

Municipal waste incineration in China reached 232 million tonnes in 2022, with increasing problems in treating waste leachate (WL). However, significant uncertainty exists in the emission performances, cost, and optimization strategies of city-level WL treatment. Herein, a bottom-up approach is utilized to investigate the WL status across over 300 cities and a life cycle thinking is employed to compare the environmental and economic effects of various WL and waste leachate concentrate (WLC) management options. Analysis reveals national production of WL has reached 57 million tonnes, with the top ten cities, including Guangzhou, Shanghai, and Chongqing, contributing 20.6 %. Biological coupled chemical treatment (BCT) demonstrates the best environmental performances in WL treatment technologies, while biologically coupled membrane treatment (BMT) offers the lowest economic expenses, and Mechanical Vapor Recompression (MVR) evaporation excels in treating WLC. In a business-as-usual scenario, the national carbon emissions, energy consumption, and economic costs of WL treatment are 24 million tonnes CO2 eq, 264 million GJ, and RMB 19 billion, respectively. Under the WL and WLC technology optimization scenarios, estimations indicate a reduction in carbon emissions by 80.7 % (equivalent to 55.1 million trees) and 19.7 % (equivalent to 13.5 million trees), respectively. Viewed holistically, replacing BMT with BCT emerges as the optimal mitigation strategy, with the synergistic optimization of BMT and MVR evaporation systems following closely. In the formulation of the technology transition strategies, the urban economy, strategic positioning, and geographic location also should be considered apart from the technological aspects, to steadily achieve sustainable co-benefits across environmental and economic dimensions.

Integrating Mechanistic-Empirical Pavement Analysis in the Life Cycle Assessment Use Phase and Monetization of Environmental Impacts to Promote Low Carbon Transportation Materials

This study attempted to integrate the Mechanistic-Empirical Pavement Design Guide (MEPDG) analysis into the life cycle assessment (LCA) framework to explore the potential of terminal blend rubberized bitumen (TBRB) technology as a sustainable alternative to traditional paving materials in the United Arab Emirates (UAE). In addition, the concept of environmental impact monetization is introduced for quantifying shadow prices to be used in cost–benefit analyses and encourage the adoption of sustainable technologies in pavement construction. The findings demonstrate that hot mixed asphalt (HMA) with TBRB outperforms asphalt mixtures with neat bitumen (NB) and polymer-modified bitumen (PMB) containing 7% linear styrene–butadiene–styrene, with respect to durability and environmental impacts. The cradle-to-grave analysis, which includes maintenance and rehabilitation cycles based on the MEPDG results, alters the hierarchy among scenarios compared to conventional cradle-to-gate analyses, highlighting the importance of the use phase in LCA. Overall, the asphalt mixture with TBRB exhibits 83% and 63% less global warming potential than mixtures with NB and PMB, respectively. The monetization process through the distance-to-target approach returned the shadow price of US$157 per metric ton of CO2eq in the UAE. Based on this value, the HMA with TBRB, if selected over those with NB and PMB, offers environmental savings of US$47,186/km-lane and US$15,852/km-lane for the case study investigated.

Life cycle environmental evaluation of medical oxygen masks in the UK

In a clinical setting, medical oxygen masks (MOMs) are made using lightweight and transparent materials with Polyvinyl Chloride (PVC) being a popular choice. Environmental concerns around the use of PVC have arisen due to the toxicity of plasticisers required; in particular the use of increasingly regulated phthalate (Pht) based plasticisers. Non-Pht plasticisers and alternative materials to PVC are being sought as potential replacements in order to keep MOMs in line with current and expected regulations. This study explores the environmental impacts of three (low-flow) MOMs using a life cycle assessment approach from cradle to grave with a functional unit defined as ‘one single-use low-flow medical oxygen mask for adult use in the UK’. The results account for all 11 impact categories as provided by the CML-IA baseline v3.03 methodology. PVC is the main component of two MOMs: mask A using a non-Pht based plasticiser and mask C (a hypothetical mask) using Pht-based plasticiser DEHP. For Mask B, styrene-ethylene-butadiene-styrene based thermoplastic elastomer (TPE-S) and polypropylene is used instead of PVC. Mask B shows the lowest environmental impact across all impact categories. For six out of 11 impact categories (including global warming potential and ozone depletion), mask C scores highest, whereas mask A is highest for the other five categories (with large impacts in human toxicity and ecotoxicities). Two scenario analyses show the importance of supply chain logistics (i.e., the location of the manufacturing site and location of end user) on overall environmental impact. The results of this study intend to provide evidence to policy makers, healthcare professionals, and manufacturers of MOMs to improve the overall environmental impacts of these products, as they contribute around 4437 tonnes of CO2 eq. yearly in the UK alone. The results show that switching from plasticised PVC to TPE-S would reduce the impacts of the use of MOMS within the UK by 2755 tonnes of CO2 eq. per year.

Techno-economic evaluation of GHG emissions mitigation of biomethane upgrading technologies

The current trend in the European biogas industry is to shift away from electricity production towards the production of biomethane for the need to replace natural gas. The upgrading of biogas to biomethane is normally performed by separating the biogas in a stream containing natural gas grid quality methane and a stream containing mostly CO2. The CO2 stream is normally released into the atmosphere; however, part of the methane may still remain in it, and, if not oxidized, even a small fraction of methane released may jeopardise all the GHG emissions savings from producing the biomethane, being methane a powerful climate forcer. Scope of this work is to assess the opportunity cost of installing an Off Gas Combustion (OGC) device in biomethane upgrading plants. The currently available technologies for biogas upgrading to biomethane and the most common technology of OGC (the Regenerative Thermal Oxidisers, RTO) are described according to their performances and cost. Then the cost per tonne of CO2eq avoided associated to the adoption of RTO systems in relation to the upgrading performance is calculated to identify a potential threshold for an effective and efficient application of the RTO systems. It is found that, in case of upgrading technologies which can capture almost all biomethane in the upgrading off-gas (i.e. 99.9%), currently the adoption of an RTO to oxidise the methane left in the off-gas would add costs and need additional fuel to be operated, but would generate limited GHG emission savings, therefore the cost per tonne of CO2eq emissions avoided would result not competitive with other GHG emissions mitigation investments. While the installation of RTOs on upgrading systems with a methane slip of 0.3%, or higher, normally results cost competitive in reducing GHG emissions. The installation of an RTO on systems with a methane slip of 0.2% results in a cost per tonne of CO2eq emissions avoided of 50–100 euro, which is comparable to the current cost of CO2 emissions allowances in the EU ETS carbon market, representing therefore a reasonable choice for a threshold on methane slip regulation for biogas upgrading systems.

Power Sector Under Climate Scenario: A Study of Climate Policy Impact on Indonesia Electricity System

In the sixth assessment report, the IPCC indicates that global temperature increased by 1.11 (±0.13) degrees Celsius in 2019 due to 6.5 gigatons of CO2eq of greenhouse gas emissions into the atmosphere. The power sector is a major global greenhouse gas emitter, particularly in Indonesia. Indonesia’s electricity sector emitted 149.90 million tons of CO2eq greenhouse gas in 2020, which is expected to increase to 158.30 million tons of CO2eq in 2021. Indonesia has committed to reducing greenhouse gas emissions according to the Paris Agreement. The Paris Agreement has been ratified into national law, accommodating Indonesia’s roadmap to net zero by 2060. The emissions reduction target was published in 2022 through the enhanced Nationally Determined Contribution (NDC). This study aims to analyze the impact of climate policy in Indonesia’s electricity sector to meet the net zero emissions target by 2060. Projection and calculation in this study were conducted using the Low Emissions Analysis Platform (LEAP). Data from 2020, including electricity demand, existing capacity, energy production, energy intensity, lifetime, and capacity factor, were used to support LEAP analysis. The data were obtained from the PLN statistical book, PLN sustainability report, Indonesia’s statistical book, and climate change mitigation and adaptation reports in Indonesia. This study developed three climate scenarios, including business as usual (BAU), sustainable development (SD), and low-carbon development (LCD). These scenarios draw upon current climate policies that have various impacts on electricity generation in Indonesia. Based on LEAP analysis, by 2060, energy demand is expected to increase to 300.36 MTOE (BAU), 200.93 MTOE (SD), and 76.97 MTOE (LCD). Consequently, each climate scenario requires an increase in installed capacity to 821.82 GW (BAU), 727.06 GW (SD), and 334.58 GW (LCD). The renewable energy mix is projected to be 21% (BAU), 69% (SD), and 100% (LCD). Each scenario requires investment to develop capacity to meet energy demand. The investment cost is estimated to be 1,671.58 million USD (BAU), 1,537.64 million USD (SD), and 816.51 million USD (LCD). GHG emissions are projected to rise to 1,746.31 million tons of CO2eq (BAU) and 264.39 million tons of CO2eq (SD). However, the LCD scenario expects to achieve net zero emissions by 2060.

Techno-Economic Assessment of Molten Salt-Based Concentrated Solar Power: Case Study of Linear Fresnel Reflector with a Fossil Fuel Backup under Saudi Arabia’s Climate Conditions

Concentrated solar power (CSP) has gained traction for generating electricity at high capacity and meeting base-load energy demands in the energy mix market in a cost-effective manner. The linear Fresnel reflector (LFR) is valued for its cost-effectiveness, reduced capital and operational expenses, and limited land impact compared to alternatives such as the parabolic trough collector (PTC). To this end, the aim of this study is to optimize the operational parameters, such as the solar multiple (SM), thermal energy storage (TES), and fossil fuel (FF) backup system, in LFR power plants using molten salt as a heat transfer fluid (HTF). A 50 MW LFR power plant in Duba, Saudi Arabia, serves as a case study, with a Direct Normal Irradiance (DNI) above 2500 kWh/m2. About 600 SM-TES configurations are analyzed with the aim of minimizing the levelized cost of electricity (LCOE). The analysis shows that a solar-only plant can achieve a low LCOE of 11.92 ¢/kWh with a capacity factor (CF) up to 36%, generating around 131 GWh/y. By utilizing a TES system, the SM of 3.5 and a 15 h duration TES provides the optimum integration by increasing the annual energy generation (AEG) to 337 GWh, lowering the LCOE to 9.24 ¢/kWh, and boosting the CF to 86%. The techno-economic optimization reveals the superiority of the LFR with substantial TES over solar-only systems, exhibiting a 300% increase in annual energy output and a 20% reduction in LCOE. Additionally, employing the FF backup system at 64% of the turbine’s rated capacity boosts AEG by 17%, accompanied by a 5% LCOE reduction. However, this enhancement comes with a trade-off, involving burning a substantial amount of natural gas (503,429 MMBtu), leading to greenhouse gas emissions totaling 14,185 tonnes CO₂ eq. This comprehensive analysis is a first-of-a-kind study and provides insights into the optimal designs of LFR power plants and addresses thermal, economic, and environmental considerations of utilizing molten salt with a large TES system as well as employing natural gas backup. The outcomes of the research address a wide audience including academics, operators, and policy makers.