Highest GHG Emissions Research Articles

Stratospheric injection of solid particles reduces side effects on circulation and climate compared to SO2 injections

Abstract Most research of stratospheric aerosol injection (SAI) for solar radiation modification (SRM) has focused on injection of \ce{SO2}. However, the resulting sulfuric acid aerosols lead to considerable absorption of terrestrial infrared radiation, resulting in stratospheric warming and reduced cooling efficiency. Recent research suggests that solid particles, such as alumina, calcite or diamond, could minimize these side effects. Here we use, for the first time, the atmosphere-ocean-aerosol-chemistry-climate model SOCOLv4.0, incorporating a solid particle scheme, to assess the climatic impacts of SAI by these injection materials. For each substance, we model tropical SAI by means of constant yearly injection of solid particles, aimed to offset the warming induced by a high-GHG emission scenario over the 2020-2100 period by 1 K. We show that solid particles are more effective than sulfur at minimising stratospheric heating, and the resulting side-effects on the general atmospheric circulation, stratospheric moistening, and tropopause height change. As a result, solid particles also induce less residual warming over the Arctic, resulting in greater reduction of GHG-induced polar Amplification compared to sulfuric acid aerosols. Among the materials studied here, diamond is most efficient in reducing global warming per unit injection, while also minimizing side effects.

EU geographical islands as leaders of green energy transition

This paper reviews how European islands are taking the lead in the European Union (EU) Clean Energy Transition by reviewing the lessons learned in the EU Bridge initiative and in a number of EU co-funded projects such as NESOI, RE-EMPOWERED, REACT, IANOS, LOCALRES, MASTERPIECE, SINNOGENES, SMHYLES, STEPWISE, and ISLET. Islands encounter significant difficulties in the management of their energy systems, including strong seasonal variations in energy demand, high operational costs and GHG emissions for energy production, weak energy grids, lack of technical skills, and difficult access to finance. However, they also have positive features that make them ideal laboratories for energy transition, including high potential for renewables, small-scale and strong community structures, and high energy prices, which make most solutions cost-effective. Each of the projects contributing to the paper has been supporting the islands’ energy transition, leveraging different enabling technologies, such as renewable energy production systems, smart grids, advanced energy storage systems, and local energy community schemes. The results from these projects underline the need for tailored energy planning, considering geographical and socio-economic particularities, the need to engage the local population in the definition of the most suitable decarbonization pathways for the island, and a number of lessons learned on the technologies that have the highest potential for being tested on islands and then being replicated on the mainland. Therefore, this study concludes that renewable energy solutions coupled with different technologies (storage, mobility, district heating/cooling, etc.) and leveraging powerful community integration confirm that European islands can drive the decarbonization strategy of the EU.

Integrated risk analysis for urban flooding under changing climates

Urban flooding poses significant threats to human lives and urban development worldwide, while the impact of climate change on urban flooding remains unclear. To systematically analyze the variabilities of hydrological patterns and urban flooding under changing climates, this study coupled the downscaled general circulation model (GCM) projection with hydrologic-hydraulic modeling, with consideration of both the low-greenhouse gas (GHG) emission scenario of SSP1–2.6 and the high-GHG emission scenario of SSP5–8.5. Results demonstrated that the original GCM projection effectively captured the changing trend of rainfall patterns in the given area, with an overestimation of rainfall peaks. The GCM downscaling through the k-nearest neighbors (kNN)-based analog method significantly improved the model accuracy. Scenario analysis indicated that climate change significantly affected the regional hydrology, with the precipitation, surface runoff, and floods increasing by a maximum value of 17.10%, 12.66%, and 63.26%, respectively. The interannual comparison demonstrated that the temporal variability in precipitation and flood intensified with the increase in GHG emissions during 2025–2100, suggesting the uncertainty of long-term climate forecasts. According to flood risk analysis, long-term and short-term floods exhibit varied changing trends across climate scenarios, despite the strong correlations between precipitation and runoff, implying the complexity of flood generation mechanisms. The methods and findings herein provide valuable insights for policymakers and practitioners, to cope with the increasing urban flood risk within the context of evolving environment.

Climate justice beliefs related to climate action and policy support around the world

AbstractClimate justice is increasingly prominent in climate change communication and advocacy but little is known about public understanding of the concept or how widely it resonates with different groups. In our global survey of 5,627 adults in 11 countries spanning the global north and south, most participants (66.2%) had never heard of climate justice. Nonetheless, endorsement of climate justice beliefs was widespread (for example, acknowledging the disproportionate impact of climate change on poor people and the underpinning roles of capitalism and colonialism in the climate crisis). Climate justice beliefs were also associated with various indices of climate action and policy support. These associations tended to be stronger in countries with high GHG emissions and where social inequality is also more politically salient. The results highlight the value of climate justice as a motive for climate action across diverse geographical contexts.

Substantial reduction in population exposure to sea level changes along the Chinese mainland coast through emission mitigation

Abstract Rising sea level increases the exposure to flooding and related damage in coastal areas with high population density and substantial economic activity. As global temperatures continue to rise due to climate change, sea levels have been consistently increasing and are projected to continue this upward trend. This study assesses the future exposure at provincial and city levels populations coastal mainland China coast to local sea level changes under five greenhouse gas (GHG) emission scenarios from IPCC-AR6, as well as two low-confidence scenarios accounting for the potential impact of uncertain ice sheet processes with low- and high-GHG emissions. We incorporate spatial heterogeneity into regional sea level projections and population projections from 2020 to 2100, extreme sea levels (ESLs) of 10-, 50-, and 100 year return periods (RP), and local coastal protection standards. Our findings indicate that the inundated areas expand continuously within the century with heightened exposure under higher emission scenarios. Although the coastal population is projected to decline, the fraction of the coastal population exposed to flooding increases across all scenarios, with accelerated growth under higher GHG emissions and higher ESLs. Zhejiang and Jiangsu emerge as the provinces most exposed to sea-level rise, whereas Taizhou, Nantong, Wuxi, Panjin, and Huzhou are identified as the top five cities with the highest population exposure to local sea level rise (SLR). Transitioning towards a sustainable scenario (i.e. SSP1-2.6) rather than a fossil fuel-intensive one (i.e. SSP5-8.5) can reduce the local SLR and substantially mitigate these exposures. Compared to the median projections under SSP5-8.5, aligning GHG emissions with SSP1-2.6 could reduce population exposure substantially in all coastal provinces, especially in Jiangsu, where population exposure to 100 year RP coastal floods would be reduced by ∼1.6 M in 2050 and by ∼5.4 M in 2100.

Stakeholder Insights: A Socio-Agronomic Study on Varietal Innovation Adoption, Preferences, and Sustainability in the Arracacha Crop (Arracacia xanthorrhiza B.)

Arracacha, a root crop indigenous to the Andean region of South America, holds significant agronomic and socio-economic importance in Colombia. The study aims to evaluate the impacts of adopting the ‘Agrosavia La 22’ variety on agricultural sustainability and productivity, encompassing economic, environmental, and social dimensions. Additionally, it analyzes the preferences of farmers and other stakeholders regarding the sustainability of the introduced technological innovations. Conducted over three years (2021–2023), the study offers comprehensive insights into adoption trends and stakeholder perceptions. Utilizing the Ambitec-Agro methodology, the research assesses the environmental, social, and economic impacts of ‘Agrosavia La 22’. Data collection involved field observations and interviews with farmers and key actors in the arracacha supply chain. Results indicate a substantial increase in the cultivated area from 1500 hectares in 2021 to 2650 hectares in 2023, with the proportion of total cultivated area rising from 47.6% to 84.1%. Economically, ‘Agrosavia La 22’ demonstrated significant input cost savings, reducing costs by USD 347 per hectare by 2023 and enhancing producer surplus from USD 30.95 to USD 651.16 per hectare. Yield comparisons show higher median yields for ‘Agrosavia La 22’ (20 t ha−1 in 2023) compared to traditional varieties (12.5 t ha−1). Socially, there was a marked improvement in farmers’ income perceptions, and environmentally, there was a reduction in greenhouse gas emissions (324.05 kg CO2-eq ha−1) due to optimized fertilizer and pesticide applications. Eco-efficiency (EE) analysis shows that ‘Agrosavia La 22’ consistently demonstrated positive EE values, indicating economic viability alongside lower GHG emissions. In 2021, its EE stood at 2.2 USD/kg CO2-eq, increasing to 27.75 USD/kg CO2-eq by 2023, reflecting substantial economic gains relative to environmental impact. Conversely, the traditional variety initially exhibited lower EE due to high GHG emissions. Challenges such as soil quality decline and market price volatility were noted. Overall, the findings underscore the economic, social, and environmental benefits of ‘Agrosavia La 22’. Furthermore, the methodology used in this study can be applied to the evaluation of other varietal innovations in developing countries with limited resources for assessing agricultural technology impacts.

Predicting the economic feasibility of solar-based net-zero emission buildings (NZEBs) in the United States non-residential sector

Buildings have significantly contributed to high energy demand (30.3%) and GHG emissions (26.1%) worldwide. Consequently, many developed countries have set carbon-neutral targets for 2050, mandating that all new constructions thereafter be designed as net-zero emission buildings (NZEBs). To achieve this goal, one of the most practical sources of renewable energy, solar power, is employed in this study to estimate the economic feasibility of implementing NZEBs in the non-residential sector of the United States. While past studies have typically estimated the economic payback period of solar power technology by assuming fixed values for “PV energy conversion rates (%)” and “investment costs ($USD)”, this paper carefully investigated the economic feasibility of “solar-based NZEBs” by precisely tracking these dynamic future changes in PV panels. These techno-economic variables were carefully predicted using a statistical technique known as the five-parameter logistic (5 PL) function. The results show that Site 4 is the only solar region suitable for implementing “PV-integrated NZEBs”, reaching a payback period of 8.44 years in 2040 (Scenario 1). Furthermore, with small technological improvements in PV energy efficiency (%), buildings located in Site 3 and Site 4 can meet the net-zero emission target with payback periods of less than 10 years in 2034 (Scenario 2). Finally, starting in 2044, the “PV-integrated system” will have a payback period of approximately 7 years in most study locations, even without federal support for the solar investment tax credit (SITC). Accordingly, federal support for solar power generation will be more effective if the SITC rate is gradually reduced by 2.5% annually starting in 2033. In conclusion, this paper suggests the economic feasibility of implementing solar-based NZEBs in the United States non-residential sector by considering the synergetic effect of technological improvement and cost reduction in PV-integrated systems.

Looking for the ecological transition of Mediterranean small ruminant sector. Characterization and main drivers of environmental performance of the Sardinian sheep farming systems

A Life Cycle Assessment (LCA) study was carried out to assess the environmental profile of the main Sardinian dairy sheep farming systems, with the scope to provide a detailed and robust baseline for the identification of effective mitigation solutions at farm level and to develop environmental strategies at regional scale. Both product- and area-based functional units (FUs) were adopted, considering sixteen impact categories and soil carbon sequestration estimates as well. Water Use, Climate Change, Land Use, Ecotoxicity Freshwater, Marine Eutrophication and Fossils Resource Use resulted the main impact categories, cumulatively contributing over 80% of the total environmental impact (single score). Environmental performances significantly varied according to the geo-pedological traits of the different sheep milk production areas and were driven by the farming systems’ structure and production level. The group of farms located in less fertile areas showed significantly worse environmental performance per kg of normalized milk for the impact categories Climate Change and Land Use, whereas no significant differences were observed for the remaining main impact categories. Considering the area-based FU, this farm group resulted less impacting for all main categories compared to the group of farms located in more plain and productive soils, with a significantly lower impact observed for Marine Eutrophication and Fossils Resource Use. Regardless of the FU used, feed supply management represented a key area of improvement, and soil carbon sequestration impact compensated the high GHG emission intensity of grassland-based farms despite the limited nutritional value of natural pasture. Regional strategies should be based on ecosystem services optimization and eco-innovative solutions tailored according to both the specific geo-pedological conditions and the production level of each farming system.

Greenwashing or Going Green? An Empirical Analysis of the Drivers and the Effects of Carbon Offsets and Renewable Energy Certificates on Firm Performance

Carbon offsets and renewable energy certificates (RECs) are widely used instruments that help firms mitigate their greenhouse gas emissions (GHG). This paper investigates which internal firm characteristics are associated with investments in carbon offsets or RECs and how these purchases impact firms’ performance. Based on data from publicly traded firms in North America and Europe from 2012-2022, this paper uses a propensity score matching approach to analyze the effects of these investments on firms’ environmental scores, GHG emissions, and financial performance. Additionally, this paper employs an instrumental variable approach to examine whether board gender diversity increases carbon offset or REC purchases. The findings reveal that firms that purchase carbon offsets or RECs face higher environmental scores and higher GHG emissions, suggesting corporate greenwashing behavior. This paper also demonstrates that these purchases lead to higher sales, profitability, and assets, but lower Tobin’s Q for REC buyers. Lastly, this paper finds that a greater presence of women on the board does not lead to greater purchases of carbon offsets or RECs.

Assessing the Sustainability and Performance of Hempcrete

Aim: Traditional construction materials like cement, concrete, glass, asphalt, and steel require more energy in the manufacturing process, which results in high GHG emissions. Therefore, researchers from all over the world are focusing on solutions to tackle carbon emissions, with hempcrete emerging as a less polluting construction material. Hempcrete is a bio-composite comprising a woody core of hemp stem and hydrated lime. The objective of the study is to find out the physical and mechanical properties of hemp-lime concrete. Study Design: The present research paper is part of the ongoing study on hempcrete at G.B. Pant University of Agriculture & Technology, Pantnagar, Uttarakhand, India. The present study chose an experimental research design. Methodology: The study presents its results in two parts: performance and sustainability. The first part investigates the performance of hempcrete in terms of its physical and mechanical characteristics. The researcher conducted numerous trials to fix mix designs, focusing on their workability. Cubes of size 10 cm were cast manually for five distinct mix designs. The second part of the paper examines the sustainability aspect of hemp-lime concrete via a relevant literature review. Results: During the specified time intervals of 28, 56, 84, and 112 days, the cubes exhibited a range in weight density from 506 to 674 kg/m3. In parallel, the compression test results demonstrated varying values, spanning from 0.510 Mpa to 0.810 Mpa across the same time points. Results show that there is a negative correlation between density and compressive strength and a positive correlation between density and water absorption rate. Conclusion: The results pertaining to weight density highlight the lightweight nature of hempcrete, to the extent that the cubes have the propensity to float in water. Due to its relatively low compressive strength values, hempcrete is deemed suitable for non-load-bearing applications within building construction.

Assessing the impact of climate change on dissolved oxygen using a flow field ecosystem model that takes into account the anaerobic and aerobic environment of bottom sediments

AbstractThis study examines the potential impacts of climate change on Lake Biwa, Japan’s largest freshwater lake, with a focus on temperature, wind speed, and precipitation variations. Leveraging data from the IPCC Sixth Assessment Report, including CCP scenarios, projecting a significant temperature rise of 3.3–5.7 °C in the case of very high GHG emission power, the research investigates how these shifts may influence dissolved oxygen levels in Lake Biwa. Through a one-dimensional model incorporating sediment redox reactions, various scenarios where air temperature and wind speed are changed are simulated. It is revealed that a 5 °C increase in air temperature leads to decreasing 1–2 mg/L of dissolved oxygen concentrations from the surface layer to the bottom layer, while a decrease in air temperature tends to elevate 1–3 mg/L of oxygen levels. Moreover, doubling wind speed enhances surface layer oxygen but diminishes it in deeper layers due to increased mixing. Seasonal variations in wind effects are noted, with significant surface layer oxygen increases from 0.4 to 0.8 mg/L during summer to autumn, increases from 0.4 to 0.8 mg/L in autumn to winter due to intensified vertical mixing. This phenomenon impacts the lake’s oxygen cycle year-round. In contrast, precipitation changes show limited impact on oxygen levels, suggesting minor influence compared to other meteorological factors. The study suggests the necessity of comprehensive three-dimensional models that account for lake-specific and geographical factors for accurate predictions of future water conditions. A holistic approach integrating nutrient levels, water temperature, and river inflow is deemed essential for sustainable management of Lake Biwa’s water resources, particularly in addressing precipitation variations.

Reduction of carbon footprint by using recyclable bottles—A case study on Austrian wine

A decarbonized society can only become reality if all potential greenhouse gas is leveraged. In order to achieve this, it is necessary to scrutinize all processes, to assess whether a high level of energy and material efficiency has been achieved and whether renewable energy sources are used to the maximum extent. In this investigation, we were investigating the corporate carbon footprint of a winery in Austria. All data, energy and material inputs were taken within the framework of a scenario analysis for one hectare of vineyard with a yield of a 5-year average of 5380 L. The energy and material input in a winery in Austria under the system limit considered in these calculations results in a GHG emission of about 1.04 kg per L of bottled wine (or 0.78 kg per 0.75-L bottle). On the other hand one kg of grapes would therefore cause 0.24 kg of CO2e.The GHG emissions for the production of a wine bottle in Austria causes 0.328 kg CO2 equivalent emissions. The GHG emissions for washing (0.011 kg CO2 equivalent emissions per bottle), on the other hand, amount to only 3.4% measured against a new bottle in Austria. The bag-in-box system can only be used once. This system leads to 59% higher GHG emissions per L compared to reusable bottles on the basis of 12 filling cycles (system sustainability – lightweight bottles). At a refill rate of 50% in a winery, GHG emissions are reduced to 4367 kg per ha (−32% compared to normal and new glass in the winery). The calculations show that refilling the wine bottle has the highest savings potential. Measures to achieve this multiple use should be implemented as soon as possible in the wine industry.

Spatial vulnerability assessment of urbanites of Rawalpindi to the combined effects of climate change and pandemics using GIS mapping

ABSTRACT Pakistan is urbanising at an extremely high pace and if this urbanisation is left unplanned, it can not only increase the vulnerability of its residents, but it can be the source of high GHG emissions, thereby increasing vulnerability to climate change. Moreover, not all city inhabitants are equally vulnerable to climate change and Pandemics like Covid-19. This study estimated the vulnerability ranking of urban union councils of Rawalpindi through a composite index without assigning weights, considering 20 physical, economic, social and institutional indicators as drivers of vulnerability, with an emphasis on climate change and the outbreak of chronic diseases. A survey is conducted from the urban residents of Rawalpindi, to measure the vulnerability towards climate change and the outbreak of Covid-19. The sample size was 440 households. The results showed that union councils of New Katarian-II, Dhaman and MC Stadium B Block were less vulnerable as compared to other areas of Rawalpindi with the lowest vulnerability ranking of MC Stadium B Block as 404 and the most vulnerable ranking of Dhok Ratta, UC-2 as 895. Densely populated areas of Dhok Ratta were more vulnerable to high chronic disease exposure and death rates. This study concluded that high population density and composition, low healthcare facilities in slums coupled with low income were the main reasons for chronic disease outbreaks in urban areas. Urban planning or master plans can be a solution for such densely populated areas and high-rise buildings with green infrastructure can reduce the impact of the heat island effect.

Current Status and Economic Prospects of Alternative Protein Sources for the Food Industry

The rising demand for novel and alternative protein (AP) sources has transformed both the marketplace and the food industry. This solid trend is driven by social awareness about environmental sustainability, fair food production practices, affordability, and pursuit of high-quality nutritional sources. This short review provides an overview of key aspects of promising AP sources (plants, algae, insects, fungi and cultured protein) as well as the economic potential, prospects, and operational challenges of this market. The low environmental performance of livestock production, associated with high GHG emissions and land use, can be overcome by less resource-intensive AP production. However, despite the forecasted expansion and improved economic viability, key challenges such as regulatory concerns, consumer acceptance and product functionality still need to be addressed. While the consumption and production of plant-based products are relatively well established, research and development efforts are needed to remediate the main commercialization and manufacturing issues of unprecedented protein sources such as cultured protein and the emerging edible insects sector.

Energy and GHG emissions assessment for biochar-enhanced advanced biofuels value chains

Biochar has an enormous potential to store carbon in the long-term. Differently than BioEnergy Carbon Capture and Storage (BECCS) technologies, biochar incorporates biogenic carbon in a solid form that offers multiple benefits as carbon sink, soil improver or for advanced materials production. The present study proposes an innovative approach, where carbon sequestration through biochar is obtained through the integration of slow pyrolysis with fast pyrolysis in decentralised biorefining systems, and then converted producing drop-in fuels from pyrolysis oil hydrotreating or gasification and Fischer-Tropsch (FT) synthesis. The scope is either to achieve negative GHG emissions assigned to advanced biofuels, or to export the generated carbon credit for the carbon markets (i.e. outside the biofuels carbon intensity). The innovative concept entails process integration and optimisation for the different stages of biomass drying, conversion and upgrading into biofuels in a way to reduce fossil-based inputs, applying a full value chain approach. Methodological choices for the assumptions on life cycle emissions calculation are discussed, evaluating the environmental performances by comparing the new concept to traditional biofuels value chains. Using a tailored lifecycle accounting methodology, this paper demonstrates that high GHG emissions savings can be achieved. The improved scenario shows how the carbon sequestration with biochar further reduces the carbon intensity up to –4.2 gCO2e MJ−1 for pyrolysis oil-based fuels, and to −20.2 gCO2e MJ−1 for FT-based fuels: this demonstrated that carbon negative sustainable biofuels can be obtained. The study demonstrates that an integrated biorefinery of 100 MW capacity can deliver additional 13.3 and 6.8 ktons of CO2e of GHG savings of per year, from drop-in fuels made of hydrotreated pyrolysis oil and FT synthesis, respectively.

Mapping lock-ins and enabling environments for agri-food sustainability transitions in Europe

European agri-food systems must overcome structural lock-ins to achieve more sustainable modes of production and consumption. Yet European regions are highly diverse, and we lack understanding of how different regional characteristics may enable or inhibit sustainability transitions. This hinders the development of context-tailored governance strategies. In this paper, we identify and apply sets of spatial indicators to map the regional potentials for agri-food transitions. We first analyse the strength of lock-in to the incumbent agro-industrial paradigm. We then map the enabling environments for two alternative agri-food networks—multifunctional value chains and civic food networks—that each embed distinct social–ecological qualities of agriculture and food. Results demonstrate a large spatial diversity in transition potential, with stronger lock-ins throughout North and Western Europe and stronger enabling environments for agri-food transitions in Italy, France, Switzerland, and Southwest Germany. We find that lock-ins are strongest in livestock-dominated regions and are associated with higher GHG emissions and excess nitrogen levels. Our study demonstrates the need for coordinated public policies that (1) leverage region-specific transition potentials and (2) enable complementary innovations in market-based and community-led networks.

Modelling the future climate impacts on hydraulic infrastructure development in tropical (peri-)urban region: Case of Kigali, Rwanda

The current global climate has shown a significant change, mostly resulting from human-induced activities. Frequent experiences of extreme rainstorms, deadly landslides, and floods followed by the destruction of roads, bridges, drainage, buildings, agriculture, and other infrastructures have been appearing across the globe along with extensive socio-economic effects including human lives losses whereby tropical Africa is among the greatly affected regions. Several studies in the region acclaim the increase of climate-related extremes due to a gradual climate variation. Hence, this study aimed to evaluate how existing water structures might respond to the future climate, which is getting more severe and frequent in the region. The study was conducted on the Nyabugogo River catchment (NRC), covering a huge part of the Kigali metropolitan area. It was carried out through a downscaled global climate model (CMIP6 GCM) projection coupled with a joint SWAT + hydrological model and HEC-RAS hydrodynamic simulation. The study showed that the annual precipitation in Kigali might keep increasing, resulting in increased risks of extreme weather events. The study identified up to 38% (+514.9 mm) annual precipitation increment, which resulted in more than a doubled flow rate (+28.0 m3/s) increment by the end of the century under a high greenhouse gas emission scenario (ssp585). As a result, hydrodynamic simulations revealed that the Bridge-1 in NRC might fail to accommodate the 50-year return peak storm under ssp585. Henceforth, there is a need to adopt high GHG emission scenarios in critical infrastructure development. Further, enforcing green-grey infrastructures in flood risk-low resilient areas is recommended to improve climate resilience. Thus, the results of this study might prove useful in climate-resilient infrastructure development and other pre-emptive adaptation practices, most importantly building anticipated resilience against climate-related hazards.

A Review of the Energy Policies of the BRICS Countries: The Possibility of Adopting a Just Energy Transition for South Africa

This review focuses on the Just Energy Transition (JET) policies of the BRICS member countries with the aim of finding lessons and possibly adopting some of the key energy policy aspects utilised in other countries as a benchmark for the South African context. We consider the present stage of JET in South Africa while being cognisant of the energy source mix supporting the electricity sector and the lifespan and condition of its power plants. An analysis of the energy mix revealed that all nations are dependent on electricity for energy, which is produced predominantly from fossil-fuelled power plants with high GHG emissions (concentrating on high CO2 emissions). It was concluded that some of the lessons learnt from the BRICS countries might be incorporated into a South African energy plan for the transition, with options and guidance for the formulation of policies. This study will attract a responsible, environmentally conscious audience that has the commitment and drive to combat global warming and curb climate change.

Leveraging food waste for electricity: A low-carbon approach in energy sector for mitigating climate change and achieving net zero emission in Hong Kong (China)

In recent years, food waste has been a global concern that contributes to climate change. To deal with the rising impacts of climate change, in Hong Kong, food waste is converted into electricity in the framework of low-carbon approach. This work provides an overview of the conversion of food waste into electricity to achieve carbon neutrality. The production of methane and electricity from waste-to-energy (WTE) conversion are determined. Potential income from its sale and environmental benefits are also assessed quantitatively and qualitatively. It was found that the electricity generation from the food waste could reach 4.33 × 109 kWh annually, avoiding equivalent electricity charge worth USD 3.46 × 109 annually (based on US' 8/kWh). An equivalent CO2 mitigation of 9.9 × 108 kg annually was attained. The revenue from its electricity sale in market was USD 1.44×109 in the 1st year and USD 4.24 ×109 in the 15th year, respectively, according to the projected CH4 and electricity generation. The modelling study indicated that the electricity production is 0.8 kWh/kg of landfilled waste. The food waste could produce electricity as low as US' 8 per kW ∙ h. In spite of its promising results, there are techno-economic bottlenecks in commercial scale production and its application at comparable costs to conventional fossil fuels. Issues such as high GHG emissions and high production costs have been determined to be resolved later. Overall, this work not only leads to GHG avoidance, but also diversifies energy supply in providing power for homes in the future.

Assessing GHG emissions of food consumption towards low-carbon transformation in China

Food is the link between sustainable development and human nutrition and health. The unreasonable diet structure not only increase health risks, but also increases GHG emissions. However, existing dietary guidelines concentrate on human nutritional intake requirements, without considering the impact on GHG emissions. Here, we measure China's food GHG emissions at four stages. We find that emissions from the production and processing stages are higher than those from the transportation and marketing stages for all the food types. Three fifths of provinces have higher GHG emissions from plant-based foods than from animal-based foods due to different dietary habits. By comparing different dietary guidelines, we propose a Low-carbon Health Dietary Guideline (LDG) that fully considered nutritional and emission reduction targets, and tailor the diet to suit differences in age, race, gender and income. The results show that under the LDG diet, food-related GHG emissions of China in 2050 are 167 Mt. CO2-eq, 19% less than under Business as Usual (BAU) and 34% less than under Chinese Dietary Guidelines (CDG).