Greenhouse Gas Emission Mitigation Potential Research Articles

Exploring Synergistic GHG Emissions Mitigation Potential and Costs of Room Air Conditioners.

This study explores the potential of synergistically reducing direct (refrigerant) and indirect (electricity) greenhouse gas (GHG) emissions in the global room air conditioning (RAC) sector, based on 80% of global RAC manufactured in China. Three scenarios are evaluated: Business-as-usual (BAU) based on maintaining refrigerant and energy efficiency levels from 2021 China RAC sales shares, Kigali Amendment compliant with 10% energy efficiency improvement by 2025 (KAE), and accelerated refrigerant transition and energy efficiency improvement (ATE). Each scenario considers the costs of refrigerant and efficiency measures for export market groups based on Kigali Amendment classifications. BAU predicts around 1 Gt CO2-eq average annual global RAC emissions (2022-2060). Cumulative emission reductions in China's RAC manufacturing under KAE and ATE are 12.2 and 17.2 Gt CO2-eq A5II and A5I (except China), presenting cost-effective abatement measures, with average costs of -$51.4 and -$68.8/t CO2-eq in KAE and ATE. Cumulative average abatement costs are around $18 and $4/t CO2-eq globally. KAE and ATE scenarios would avoid surface temperature rises of 0.023 (±0.002) °C and 0.027 (±0.003) °C, respectively, versus BAU. Collaboration between China and importing countries is urged to enhance energy efficiency in RACs traded, ensuring sustainable mitigation aligned with the Kigali Amendment.

Quantifying greenhouse gas emissions mitigation potential in China's agricultural plastic greenhouses

To promote sustainable intensification and provide guidance for decisionmakers, we must understand the potential for mitigating greenhouse gas emissions in greenhouse cultivation. Therefore, this study aimed to evaluate the greenhouse gas emission mitigation potential of agricultural plastic greenhouses in China using a combination of life cycle assessment, data envelopment analysis, and scenario analysis. We found that: (1) In China, the mean mitigation potential for greenhouse gas emission intensity related to the crop production inputs of agricultural plastic greenhouses is 1.67 kt CO2-eq/km2, demonstrating a remarkable mitigation rate of 47 %. This mitigation potential, driven mostly by fertilizer use, exhibited a spatial pattern characterized by high mitigation rates in the southern regions compared to those in the northern regions; (2) in scenarios S1 and S2, the greenhouse gas emission intensity mitigation potential of greenhouse construction materials was 0.645 kt CO2-eq/km2 and 0.968 kt CO2-eq/km2, respectively, with steel being the primary contributor to mitigation; (3) under scenarios S1 and S2, the greenhouse gas emission mitigation rates for China's agricultural plastic greenhouses were 42 % and 48 %, respectively. This study highlights the greenhouse gas emission mitigation potential of China's agricultural plastic greenhouses. To ensure sustainability in plastic greenhouses, emphasis should be placed on optimizing fertilizers and extending the lifespan of construction materials.

Hands-On Approach to Foster Paludiculture Implementation and Carbon Certification on Extracted Peatland in Latvia

Voluntary carbon markets open horizons for private companies, public institutions, and individuals developing CO2 removal projects in peatlands to reduce overall carbon footprint. These steps, however, should be in line with appropriate rewetting targets. Therefore, the baseline information about the status of the area must be assessed. Here, we follow the methodology set by the carbon certification program standards, which define the necessary steps for reference conditions assessment. In this study, we practically test the fulfillment of necessary drained peatland baseline evaluation for paludiculture and carbon certification activities. Estimates on the greenhouse gas emission mitigation potential were summarized to define priorities and propose quantifiable measures with suggested paludiculture implementation. Our estimations indicate that rewetting and paludiculture practice on 16.4 ha drained extracted peatland could omit 60.17 t CO2 annual emissions and instead capture 80.31–120.11 t CO2 per year. If drainage continues, then it poses a risk of releasing stored carbon from leftover peat deposits into the atmosphere, contributing 52,653.64 t CO2 to greenhouse gas emissions. Our hands-on approach shows that it is possible for companies to implement rewetting strategies without large EU-level project funding when the conservation and economic aspects are met, thus boosting climate mitigation actions.

Greenhouse gas emissions mitigation potential of municipal solid waste management: A case study of 13 prefecture-level cities in Jiangsu Province, China

Municipal solid waste (MSW) treatment is one of the main anthropogenic sources of greenhouse gases (GHGs). To mitigate the GHG emissions of the MSW sector, it is crucial to describe their emissions evolutions and mechanisms and propose localized mitigation measures on that basis. The logarithmic mean Divisia index model is used to identify the driving forces of MSW-related GHG emissions and explore the mitigation potential. Jiangsu, a typical province in China with 13 prefecture-level cities, is selected as the case study. The results showed that GHG emissions from Jiangsu's MSW treatment has increased by nearly 2.5 Mt in the last 20 years, as incineration replaces landfills. Economic development was the dominant positive driving force, and MSW generation intensity was the dominant negative driving force. Scenario analysis revealed that the carbon peak of MSW management could appear if MSW source separation and recycling (SSR) were implemented, reducing GHG accumulation emissions by approximately 0.3–0.4 Gt during 2022–2060. Referencing the SSR of the Shanghai pattern will generate the greatest mitigation potential of GHG emissions among the different scenario designs. Finally, policy recommendations for priority cities, consideration of population and economic factors, optimization of MSW treatment structures and improvements to SSR are proposed, which could help local- and national-level decision makers in China and other countries design policy guides to promote carbon neutrality, while simultaneously linking current research areas to waste management practices as well as promoting practices in environment and sustainability.

The effect of pretreatment choice on cellulosic ethanol production from sugarcane straw: An insight into environmental impact profile and GHG emissions mitigation potential in Brazil

The exploration of residual lignocellulosic biomass for biofuel production is crucial to achieve significant greenhouse gas (GHG) emissions mitigation within the following decades, translating to diminished agricultural environmental impact and land-use change dynamics. On the other hand, cellulosic ethanol production pathways are typically resource-intensive, in energy and chemical terms, which directly influence its carbon intensity. Pretreatment choice, to this end, is key, since it dictates the overall process performance and yield, and may include crucial flows, under the life-cycle perspective, such as solvents and other chemicals. This work, then, aims to evaluate the effect of pretreatment choice, namely hydrothermal (HT), steam explosion (SE), and alkaline (AK), in the technical and environmental performance of cellulosic ethanol production from sugarcane straw (SCS), extending this analysis to the final GHG emissions mitigation potential for gasoline and fossil-generated electricity substitution, under the Brazilian context in São Paulo. Results show that, while AK provided the highest ethanol yield, this pretreatment option gave the lowest electricity generation surplus, and its sodium hydroxide usage was identified as an important environmental hotspot in most impact categories, which narrowed down its GHG emission mitigation gap for gasoline substitution. HT and SE presented similar ethanol and electricity yields, with SE being the most balanced option in terms of productivity and environmental impact profile. By selecting the SE route, all of the available SCS in São Paulo could be converted into 10% of the Brazilian annual ethanol production, and mitigate 5.4 MtCO2e of gasoline emissions, 15% of the Brazilian Biofuel Policy (RenovaBio) target for 2022.

Greenhouse gas emissions mitigation potential from renewable energy development in Thailand’s industrial estates

This research assesses the potential of reducing greenhouse gas (GHG) emissions from the use of rooftop solar energy in factories located in Thai industrial estates. Most of the industrial plants located in industrial estate areas have large size with high production and energy intensive. The scope of the study covered all industrial factories located in the industrial estates of the Industrial Estate Authority of Thailand (IEAT). Renewable energy only considers solar rooftop installations, assessing on two levels based on the accuracy and source of the data, i.e. level 1, moderate data resolution and accuracy from database and online data of the IEAT and official website of the industrial estates, and level 2, high data resolution and accuracy from GIS data management program called QGIS program. Assessment according to level 1 is based on the proportional factor of the roof area of the potential community area. Assessment according to level 2 is based on the roof area data of general industrial and free zone obtained by using the QGIS survey through aerial imagery. The results showed that the calculation of the amount of GHG reduction potential based on the level 1 assessment, there is a potential roof area for installing solar rooftops of 12.05 million square meters, representing total installed capacity of 1,421.05 MW, equivalent to 0.95 MtCO 2e of GHG reduction potential annually. As for the GHG reduction potential from level 2 assessment from all aerial photographs, the study found that the potential roof area for installing solar rooftops is 6.55 million square meters, representing a total installed capacity of 773.02 MW, equivalent to 0.52 MtCO 2e of GHG reduction potential. The potential assessed above representing an estimated energy cost of 8,919-8,975 million baht for 1 MtCO 2e reduction of GHG emissions.

Greenhouse Gas Emission Mitigation Potential of Chemicals Produced from Biomass

The production of chemicals from biomass has received significant attention due to its potential to reduce greenhouse gas (GHG) emissions. In this work, we develop a systematic framework to quantitatively analyze the mitigation potential of 25 large-volume and promising platform biochemicals. To properly account for the energy requirements of producing different biochemicals, we construct material and energy balances of the biorefinery and develop simulation and optimization models to calculate the energy needed to separate and purify these biochemicals. We show that biomass-based production can lead to significant GHG mitigation. Notably, 24 out of the 25 biochemicals have lower GHG emissions compared to their fossil-fuel-derived counterparts. Under the most conservative assumptions (i.e., 25% conversion and high separation energy), biochemicals can reduce GHG emissions by up to 88%. Under the most optimistic assumptions (i.e., 75% conversion and easy separation), the emission reductions can be as great as 94%. Finally, we discuss constraints on the fraction of chemicals that can be replaced due to biomass availability limitations and identify molecular characteristics that can be used for the prioritization of chemicals to be produced from biomass.

Trajectory, driving forces, and mitigation potential of energy-related greenhouse gas (GHG) emissions in China's primary aluminum industry

As the world's largest primary aluminum producer, China's primary aluminum industry (PAI) faces a huge challenge in reducing greenhouse gas (GHG) emissions. However, detailed research on presenting the historical trajectory of GHG emissions from China's PAI and identifying the main driving factors affecting its changes has not been completed thus far. This study quantifies the GHG emission trajectory of China's PAI from 1990 to 2018 and identifies the key driving factors affecting its changes. The results show that the total GHG emissions from China's PAI from 1990 to 2018 increased by approximately 18 times, reaching 481 Tg CO2-eq in 2018, of which 69 %, 17 %, and 14 % were electricity-related, fuel-related, and process-related, respectively. Additionally, the production activity effect is the main factor driving the increase in GHG emissions; however, the energy intensity and energy emission factor effects can effectively reduce GHG emissions. Based on this, scenario analysis is used to evaluate the GHG emission mitigation potential of China's PAI by 2030. According to our analysis, policy suggestions for mitigating the GHG emissions in China's PAI are proposed, including reducing the energy intensity, promoting clean energy use, controlling the production capacity, and decarbonizing electricity.

Climate action and food security: Strategies to reduce GHG emissions from food loss and waste in emerging economies

Peru struggles to upgrade its waste management, with landfilling only just overtaking open dumpsters as the main disposal method. Despite the benefits of this transition, including reduced environmental impacts to water and soil, previous studies demonstrated that greenhouse gas (GHG) emissions may increase if adequate levels of technological sophistication are not implemented. Considering that 58% of municipal solid waste (MSW) is organic, it seems plausible that a relevant portion of emissions can be linked directly to food loss and waste (FLW) management. This study aims to determine the GHG emissions mitigation potential in FLW compared to the current baseline scenario in 24 Peruvian cities, by modelling alternative technologies to treat organic MSW. Life cycle modelling was performed using the waste-LCA software EASETECH. Five treatment scenarios were modelled: i) open dumping; ii) landfilling with no gas treatment; iii) landfilling with landfill gas treatment; iv) landfilling with energy recovery; and, v) anaerobic digestion. GHG emissions of FLW generation proved to be substantially higher than those for FLW treatment. However, if sophisticated technologies are implemented in FLW treatment, an annual reduction of up to 1.56 Mt CO2eq could be attained. Moreover, despite the health and environmental benefits of a transition to optimized diets, in which, for example, meat consumption is reduced and vegetables are boosted, an important increase in FLW and, therefore, an increase in GHG emissions in the treatment phase is shown. However, if certain technologies, such as energy recovery or anaerobic digestion, were implemented, most carbon losses would be avoided.

From agricultural (by-)products to jet fuels: Carbon footprint and economic performance

This research assesses the well-to-tank (WTT) greenhouse gas (GHG) emissions and economic performance of an innovative bio-jet fuel via acetone-butanol-ethanol (ABE) fermentation. Dutch potato by-products from the food processing industry and sugar beets are explored as potential feedstocks. Four product systems differentiated by feedstocks, logistics and centralized/decentralized fermenters are investigated.For both feedstocks, it is found that a centralized large-scale fermentation is preferable to decentralized small-scale fermentation (25–30% less expensive and 5% lower WTT emissions). Once commercialization is reached, the cost and carbon performance of this novel bio-jet fuel could be similar to that of other alcohol-to-jet fuels. Depending on the feedstock and configuration considered, the GHG emission mitigation potential of this novel jet-fuel was estimated between 41% and 52%. To meet the EU RED II 65% GHG reduction criterion, possible options could be using low carbon-intensive processing energy and hydrogen or storing permanently biogenic carbon dioxide from fermentation.

Greenhouse gas emission mitigation potential from municipal solid waste treatment: A combined SD-LMDI model

Fast urbanization and economic prosperity generate huge amount of municipal solid waste (MSW). It is therefore critical to identify the determinants of greenhouse gas (GHG) emissions from MSW treatment and prepare potential GHG mitigation measures. A combined System Dynamics - Logarithmic Mean Divisia Index model is developed to identify the driving forces of GHG emission generated from MSW treatment and explore the mitigation potentials. Shanghai, a typical megacity in China is selected as a case study. Results showed that economic development, population scale and emission intensity were driving forces to induce GHG emissions from MSW treatment, while generation intensity and treatment structure were the factors to mitigate GHG emissions from MSW during 2000–2017. Scenario analysis further revealed that landfill gas utilization and MSW separation improvement were the most effective measures in reducing GHG emissions from MSW treatment, leading to about 88.07% and 85.48% of reduction compared with the business-as-usual scenario in 2050. Scenarios of improving incineration rate, reducing per capita MSW generation and restricting population growth will reduce GHG emissions by 72.29%, 30.06% and 0.30%, respectively. Utilizing landfill gas, improving MSW separation and promoting green behaviors are suggested to mitigate GHG emissions from MSW treatment.

Evaluating long-term greenhouse gas mitigation opportunities through carbon capture, utilization, and storage in the oil sands

Carbon capture, utilization, and storage (CCUS) has been identified as the only option for substantially reducing greenhouse gas (GHG) emissions from fossil fuel-based processes. There has been limited research into the long-term GHG reduction potential of integrating CCUS into unconventional oil extraction processes. We developed a CCUS-oil sands market penetration model and integrated it with a bottom-up energy model (LEAP-Canada) to conduct a cost-benefit case study for the Canadian oil sands. Scenarios were developed considering currently available CCUS technologies and were investigated under different carbon pricing policies. Cumulative GHG emission mitigation potential from the CCUS applications ranged from 3 to 232 million tonnes (Mt) with marginal costs of $-28–42/tCO2e. Carbon pricing led to an average 3% increase in 2050 market shares of the technologies, resulting in additional GHG abatement of 4.9% (172 Mt). CCUS was found to be the costliest GHG emission mitigation option compared to increased integration of cogeneration and energy efficiency measures. The maximum cumulative oil sands GHG emission mitigation achieved in this study was 7%. This research ultimately provides insights into applications of CCUS technologies into the oil sands industry that might be useful to industry planners and policymakers and support the sustainable development of oil sands resources.

Emissions down the drain: Balancing life cycle energy and greenhouse gas savings with resource use for heat recovery from kitchen drains

Although the food service sector is a major user of water, the potential for heat recovery from commercial kitchens’ drain water remains largely unexplored. For the first time, we compare the life cycle environmental burdens of producing and installing a heat recovery system with the environmental credits arising from energy savings for a restaurant case study, and for the entire UK food service sector. Life Cycle Assessment was applied to determine the impacts of heat recovery systems made from different materials and comprising a heat exchanger in the shape of a concentric double-walled pipe, pipework and fittings. The design option with the smallest environmental footprint combined a heat exchanger made out of polypropylene-graphite (PP-GR) with polyethylene pipework, exhibiting 80–99% less environmental impact compared with components made out of (35% recycled) copper. Contrasting the environmental impacts of two heat recovery set-ups with energy savings shows that a PP-GR based system pays back all burdens of the seven assessed environmental impact categories, within two years, while payback times for the copper-based system vary depending on the replaced energy source, and can exceed the 10 year operational lifetime of the system. When looking at typical flow-rates in UK food outlets, net environmental savings can be realised across all analysed impact categories above a threshold water consumption of 555 L/day, using current technology. Extrapolation to the UK food service sector indicates annual greenhouse gas emission mitigation potential of about 500 Gg CO2 equivalent.

Energy and water saving potentials in industrial parks by an infrastructure-integrated symbiotic model

The industrial park is a common feature in global industrial development. Sharable infrastructure, such as the centralized energy facility and wastewater treatment plant (WWTP), are widely employed in industrial parks. This study established a high-resolution inventory of 252 WWTPs and 308 energy facilities in 111 Chinese national industrial parks (NIPs), and proposed an infrastructure-integrated symbiotic model in industrial parks by establishing water-energy nexuses between WWTPs and energy facilities. A match-making process was established to uncover the feasibility of fostering symbiosis between energy facilities and WWTPs. The effluent and sludge from WWTPs can be reused in energy facilities to save freshwater withdrawals and partly reduce fossil fuel consumption, and the associated greenhouse gas (GHG) emissions can also be mitigated simultaneously. The results show that effluent and sludge from WWTPs can substitute 73.4% and 7% of the water withdrawals and energy consumption of the energy facilities, respectively. The GHG emissions mitigation potential is about 9.92 Mt CO2-eq per year, accounting for a 2.56% reduction compared to the baseline scenario. The study will also enlighten other developing countries in facilitating a circular economy by targeting industrial parks and contributing to water conservation, energy savings, and pollutant reduction.

A Dynamic Fleet Model of U.S Light-Duty Vehicle Lightweighting and Associated Greenhouse Gas Emissions from 2016 to 2050.

Substituting conventional materials with lightweight materials is an effective way to reduce the life cycle greenhouse gas (GHG) emissions from light-duty vehicles. However, estimated GHG emission reductions of lightweighting depend on multiple factors including the vehicle powertrain technology and efficiency, lightweight material employed, and end-of-life material recovery. We developed a fleet-based life cycle model to estimate the GHG emission changes due to lightweighting the U.S. light-duty fleet from 2016 to 2050, using either high strength steel or aluminum as the lightweight material. Our model estimates that implementation of an aggressive lightweighting scenario using aluminum reduces 2016 through 2050 cumulative life cycle GHG emissions from the fleet by 2.9 Gt CO2 eq (5.6%), and annual emissions in 2050 by 11%. Lightweighting has the greatest GHG emission reduction potential when implemented in the near-term, with two times more reduction per kilometer traveled if implemented in 2016 rather than in 2030. Delaying implementation by 15 years sacrifices 72% (2.1 Gt CO2 eq) of the cumulative GHG emissionmitigation potential through 2050. Lightweighting is an effective solution that could provide important near-term GHG emission reductions especially during the next 10-20 years when the fleet is dominated by conventional powertrain vehicles.

Comprehensive analysis of GHG emission mitigation potentials from technology policy options in South Korea’s transportation sector using a bottom-up energy system model

The South Korean government released a greenhouse gas (GHG) emission mitigation target for 2030 under the 2015 Paris Agreement and developed a detailed implementation plan in 2016 to achieve the target. In this study, we analyzed the GHG emission reduction potential of South Korea’s transportation sector under the implementation plan. We first identified six technology policy options already adopted or being considered for adoption by the Korean government in the near future. Next, we quantitatively analyzed the GHG emission mitigation potential of each option, as well as the combination of all the options, via the best-known and most widely used bottom-up energy system model. In addition, we estimated the marginal mitigation costs of the options and their combination. We found that more than 30% of GHG emissions can be reduced compared to the business-as-usual scenario by adopting technology options, and that most reductions can be achieved by the road transportation subsector. We also showed that a comprehensive analysis is required to estimate the total potential of the entire transportation sector, because some duplication effects exist between the options. Lastly, based on the comprehensive analysis results, we provide four implications of the plan for climate change and transportation policy makers.

Carbon Label at a University Restaurant – Label Implementation and Evaluation

Changes in human diets hold significant greenhouse gas emissions mitigation potential. In this paper, we use a field experiment to analyze the effects of implementing a label with greenhouse gas emission information for each dish at a restaurant. The traffic-light colored label was implemented in a student catering facility with 300–600 servings every day, and covered all seven dishes on offer. Individual level sales data including an anonymous identification number, gender, and age was collected both during the label phase and during a five-week control phase prior to the introduction of the label. We found that sales of green labeled (low emission) meat dishes increased by 11.5% compared to the control phase, whereas sales of red labeled meat dishes were reduced by 4.8%. Although the label had an effect on consumer behavior, emissions decreased modestly by 3.6%. We did not find evidence for different reactions to the label based on gender or age.

Li-Rich Layered Cathode Materials: Transition Metals in Transit

In the most recent issue of Nature Communications , William Gent, William Chueh, and co-authors examine in depth the electronic structure and redox processes that occur during cycling of Li 1.17 Ni 0.21 Co 0.08 Mn 0.54 O 2 and reveal an important new insight that suggests oxygen redox is coupled with local transition metal migration. Aided by a suite of cutting-edge characterization methods, the authors formulate a clear and unprecedented view of both local and averaged structure evolution during cycling.

Greenhouse gas emissions mitigation potential in the commercial and institutional sector

This study was conducted to identify energy efficiency improvement options and assess these opportunities in terms of potential of energy savings and greenhouse gas (GHG) mitigation for the commercial and institutional sector. In addition, associated GHG abatement cost (GHGAC) curves were developed. A western Canadian province, Alberta, was selected for a case study. A model was developed in the Long-range Energy Alternatives Planning system (LEAP) with 23 energy efficiency improvement scenarios associated with space heating and cooling, lighting, auxiliary equipment, and water heating in the commercial and institutional sector. The scenarios analyzed in this study quantified the reduced demand in energy use and GHG emissions as well as the abatement costs for fast (2013–2030) and slow (2013–2050) penetration periods. Ground source heat pumps (GSHPs) and efficient boilers for space heating, efficient lighting, and high-insulation in building envelopes are identified as having significant potential for GHG mitigation and have low abatement costs. A cumulative GHG mitigation of 28Mt and 55Mt is achievable in the fast and slow penetration scenarios in the sector, respectively.

Emergy and greenhouse gas assessment of a sustainable, integrated agricultural model (SIAM) for plant, animal and biogas production: Analysis of the ecological recycle of wastes

The use of ecological recycling in agriculture represents a new type of agricultural development that is coming into increasing use in China. This approach to cultivation is driven by developing reciprocating, multilevel, high-efficiency energy and material flows in the use of agricultural resources. In the present study, the emergy method was used to assess an integrated agricultural model in Northwest China consisting of multiple subsystems (walnut and grains; pigs and poultry; and biogas) by considering the partial renewability factor of each input. The recycle benefit ratio, greenhouse gas emission mitigation intensity, and conventional emergy indices of the integrated model were quantified by analyzing the structure of recycling. This model for agricultural production achieved great benefits from recycling and a net greenhouse gas emission mitigation potential of 94,174.28kg CO2-eq/yr compared to conventional production models. For example, the integrated model had improved resource and land use efficiencies, environmental performance, output per unit area, and sustainability compared to the local conventional corn production system, despite its relatively high environmental load and poor sustainability. Using renewable materials such as organic corn in place of conventional corn provides an alternative way of improving the sustainability of the integrated production system but with a considerable decrease in economic profitability.