GHGs Emissions Research Articles

Optimizing a Hybrid Wind-Solar-Biomass System with Battery and Hydrogen Storage Using Generic Algorithm-Particle Swarm Optimization for Performance Assessment

This paper investigates the optimal design of a hybrid renewable energy system, integrating wind turbines, solar photovoltaic systems, biomass, and battery and hydrogen storage to ensure a reliable energy supply at the lowest annual cost for a residential load in Kern County, USA. The hybrid generic algorithm particle swarm optimization (GAPSO) algorithm was adopted to determine the optimal configuration of parameters and cost-effectiveness, considering technical, economic, environmental, and social performance indicators. The generic algorithm (GA) and particle swarm optimization (PSO) validate the effectiveness of the proposed technique, showcasing its efficiency in system optimization. The findings indicate that GAPSO outperforms GA and PSO due to its rapid convergence, lowest final fitness value, and stable optimization process. The hybrid GAPSO's performance, combined with the different capacities of wind turbines (4,561 kW), solar PV (8,480 kW), biomass (2,261 kW), battery banks (8,000 kWh), and fuel cells (2,392 kW), resulted in an annual cost of $6,239,193; energy cost and net present value of $0.48/kWh and $101,333,937. The system maintained a supply loss of 0.8%, achieved an availability index of 99.2%, a renewable energy fraction of 88.87%, GHGs emission of 953615 kg, land use of 3842875 m2, and water consumption 528678 L respectively. GAPSO achieved a 2.17% and 0.01% improvement in cost-effectiveness and 11.11% increase in reliability compared to GA and PSO.

Insight of effects of air quality and sustainable aviation fuel blend on energy saving and emission reduction in airport

Air quality in airport attracts a widespread attention due to the emission of GHGs and pollutants related with aircraft flight. Sustainable aviation fuel (SAF) has confirmed PM2.5 reduction due to free of aromatics and sulphur, and thus air quality improvement in airport is prospected by SAF blend. Two types of SAF were assessed the potential of energy saving and emission reduction by ZF850 jet engine. FT fuel is characterized with only paraffins without aromatics and cycloparaffins while HCHJ fuels is characterized with no aromatics. The descend of air quality and SAF blend were both investigated the effect on the engine performance and emission characteristic. The critical parameters were extracted from fuel compositions and air pollutants. Ambient air with a higher PM2.5 could lead to the rise of engine emission especially in UHC and PM2.5 despite at the low thrust setting and high thrust setting, and even couple with 3.2% rise in energy consumption and 1% reduction in combustion efficiency. CO, NO and NO2 in ambient air show less influence on engine performance and emission characteristic than PM2.5. Both types of SAF blend were observed significant reductions in PM2.5 and UHC. PM2.5 reduction obtained 37.9%—99.8% by FT blend and 0.64%-93.9% by HCHJ blend through the whole trust settings. There are almost 6.67% positive benefit in TSFC through the whole thrust setting by 7% FT blend. The effects of air quality and SAF blend on engine emission present significant changes on PM and UHC but the slight change on CO and NOx. By SAF blend, the energy saving and pollutant reduction obtained could be both benefit for air quality improvement in airport and further reduce engine emission as the feedback of less pollutants in ambient air.Graphical

Carbon footprint of global rice production and consumption

Rice paddies are not only sources of staple food for half of the global population but also account for nearly half of the anthropogenic greenhouse gas emissions (GHGs) of croplands. Carbon footprint (CF) is a key tool for identifying and weighting sources of the GHGs along the food supply chain, promoting the efforts to curb these emissions within the targets of the climatic change protocol of the Paris Agreement. We introduced a comprehensive global quantification of rice CF, including direct and indirect emissions and sinks of the GHGs of inputs production, packaging, transportation, and application, soil and plant systems, farm operations, and uses of the produced biomass until the end of life. Globally, the rice CF was 2430 kg CO2eq. Mg−1 grain in 2020, of which 46% and 42% were sourced from the Gate and Grave stages, respectively, after excluding 3265 kg CO2eq. Mg−1 grain, that is the assimilated C in plant biomass. Net GHGs emissions of soil, biomass mulching and burning, and farm operations accounted for 20, 17, and 63%, respectively of the Gate stage CF. Meanwhile, food consumption contributed to the Grave stage CF by 92%. The rice CF ranged between 14 and 4854 kg CO2eq. Mg−1 grain among countries, wherein, for example, the rice CF values in Indonesia, India, Vietnam, and Russia represented 9, 50, 97, and 122% of the global average. Southeast, South, and East Asia were the major contributors (35, 34 and 18%, respectively) to the atmospheric CO2 load (2.4 Pg CO2eq.) of global rice production and consumption. This CO2 load will increase to 3.1 Pg CO2eq. in 2100, driven by a 32% growth in rice consumption. Here, we suggested an optimistic strategy (green energy use, hybridization, improving use efficiency of the inputs, and reducing food losses) to reduce the CO2 load by 60%.

‘Unlock the Complexity’: Understanding the Economic and Political Pathways Underlying the Transition to Climate-Smart Smallholder Forage-Livestock Systems: A Case Study in Rwanda

The livestock-dairy sector in Sub-Saharan Africa, particularly in Rwanda, is experiencing rapid growth due to population expansion, urbanisation, and changing food preferences. The unmet local production demands are causing soil and water pollution, competition for biomass, land, and water, but also grassland degradation, biodiversity loss, and increased GHGs emissions. Rwanda has the lowest productivity in the region, largely due to inadequate and poor-quality livestock feed resources. To increase animal productivity, promoting forage species with higher nutritional value and better adaptation to drought-prone and poor-fertility soils could be beneficial. Using a mixed-methods approach, the study explores Brachiaria forage adoption and profitability and analyses policy objectives and measures to overcome adoption barriers and promote the transition from subsistence to market-oriented systems. Results show that Brachiaria, although advantageous from an economic point of view, is characterised by very low adoption rates. Furthermore, access to extension programmes is limited and often not supported by adequate incentives. To overcome such barriers, policy interventions should be harmonised and information and knowledge management prioritised, public and private extension and advisory services (EASs) programmes coordinated, agricultural input subsidies increased, and institutional coordination promoted to enhance climate-smart animal feeding.

Does carbon pricing policy improve energy efficiency? New evidence from Canadian provinces

ABSTRACT Given the increasing damage effect of climate change, the Canadian government has taken a further step to ensure that carbon pricing is implemented in all provinces to reduce its GHGs emissions as a means of addressing climate change. Thus, this paper examines the effect of carbon pricing on energy consumption which is the main source of CO2 emission to enhance our understanding beyond carbon-pricing effects on households and revenue recycling in the prior research. Our study analyzes the energy efficiency of Canada using the province-level data between 2000 and 2021, by developing an SFA production model to understand the drivers of energy consumption and then compute the total factor energy efficiency index while controlling for the role of carbon pricing. Our empirical results reveal that increased labor input, as well as output, mitigate the rising capital-induced energy consumption, while carbon pricing policy plays no significant role in influencing energy consumption. However, the effectiveness of carbon pricing is found in reducing province-level energy efficiency. This striking evidence suggests that policymakers should consider a labor-oriented energy saving scheme and conduct a comprehensive review of the current carbon pricing policy in order to align with energy efficiency interventions toward the achievement of Canada’s Paris Agreement targets.

Green-house gas fluxes and soil microbial functional genes abundance in saturated and drained peatlands in South-West Iceland

The drainage of peatlands followed by land use conversion significantly impacts on the fluxes of green-house gases (GHGs, i.e. CO2, CH4, and N2O) to and from the atmosphere, driven by changes in soil properties and microbial communities.In this study, we compared saturated peatlands with drained ones used for sheep grazing or cultivated, which are common in South-West Iceland. These areas exhibit different degrees of soil saturation and nitrogen (N) content, reflecting the anthropic pressure gradient.We aimed at covering knowledge gaps about lack of estimates on N2O fluxes and drainage, by assessing the emissions of GHGs, and the impact of land conversion on these emissions. Moreover, we investigated soil microbial community functional diversity, and its connection with processes contributing to GHGs emission.GHGs emissions differed between saturated and drained peatlands, with increased soil respiration rates (CO2 emissions) and N mineralization (N2O), consistent with the trend of anthropogenic pressure. Drainage drastically reduced methane (CH4) emissions but increased CO2 emissions, resulting in a higher global warming potential (GWP). Cultivation, involving occasional tillage and fertilization, further increased N2O emissions, mediated by higher N availability and conditions favorable to nitrification. Functional genes mirrored the overall trend, showing a shift from prevalent methanogenic archaea (mcrA) in saturated peatlands to nitrifiers (amoA) in drained-cultivated areas.Environmental variables and nutrient content were critical factors affecting community composition in both environments, which overall affected the GHGs emissions and the relative contribution of the three gases.

Factors Determining of Carbon Emissions Voluntary Disclosure in Indonesia’s Energy Sector Companies

Reporting information on carbon emission from company operations is a form of social and environmental responsibility that contributes to the reduction of greenhouse gas emissions to achieve the SDGs target by 2030. This carbon-related reporting is the role of accountants through carbon accounting as a form of transparency and accountability, as well as an effort to reduce GHGs emissions produced by companies. This research is intended to see how energy sector companies implement voluntary disclosure of carbon emissions with several determinants which is reflected in the company size scale, the exposure carried out by companies in the company’s website media, and shareholding owned by institutions. The research population is in energy sector companies listed on the Indonesia Stock Exchange (IDX) during 2018-2022. Samples of this research used purposive sampling, so that 50 observational data were obtained consisting of 10 energy sector companies in 5 years period. Result show that media exposure influences carbon emission disclosure. Companies that present media exposure have an increase in the carbon emission disclosure level. Meanwhile, firm size and institutional ownership have no influence on the carbon emission disclosure. A company with a large size scale and high institutional shareholding does not guarantee that it will report information of carbon emission thoroughly.

Decarbonizing polyamide textile production in China: Footprints and mitigation pathways from life cycle perspective

Escalating demand for textiles has led to the entire supply chain contributing 8 % of global GHGs emissions. However, the carbon footprint (CF) and low carbon pathways of polyamide textile production remain ambiguous. Herein the CF of polyamide textile in China is evaluated using a "cradle to gate" life cycle system boundary allowing for comparison with other textile categories. To explore low carbon pathways of polyamide textile production, we introduce four groups of measures resulting in 12 scenarios. The CF of 1 kg polyamide textile is 35.37 kg CO2-eq, 1.38 and 3.91 times that of polyester and cotton textiles, respectively. Direct emissions from energy combustion, and indirect emissions from raw materials and energy production contribute 43.87 % and 56.13 % of the total CF. Emission reduction potentials vary from 51.37 % to 88.52 % across scenarios. These explored low carbon pathways should serve as references for achieving low and net zero emissions in the textile sector.

Unveiling the potential of perovskite solar systems in building integrated installations: A consequential and prospective life cycle assessment and economic analysis

This paper addresses an integrated economic and environmental assessment where a consequential and prospective life cycle approach is applied to perovskite (PSK) building integrated photovoltaic (BIPV) systems. Two configurations are considered: slanted roof (r-BIPV) installations, and the fenestration of façades (f-BIPV). Concerning r-BIPV, PSK systems are expected to compete with crystalline silicon (c-Si) modules; whereas a glass façade is chosen as an alternative reference for f-BIPV. Assuming economic rationality as the main criteria for the adoption of technologies, a deployment time for the PSK system is estimated and the economic and environmental advantages in the Italian context are evaluated. This assessment is based on three foreground scenarios addressing the gradual development of PSK systems. The results show that while c-Si modules are preferred in the market of r-BIPV systems, PSK modules will find space in f-BIPV applications. Depending on the selected scenario, the economic benefits accumulated by Italian energy users are assessed between −0.5 % and −10.3 %. On the other hand, PSK systems imply a variation of the national GHGs emissions that ranges between + 0.01 % and −7.5 %. Depending on the scenario, the PSK-based f-BIPV systems can provide either environmental benefits (i.e., cumulative energy demand) or burdens (i.e., ecotoxicity indicators).

Predicting Quercus gilva distribution dynamics and its response to climate change induced by GHGs emission through MaxEnt modeling

Quercus gilva, an evergreen tree species in Quercus section Cyclobalanopsis, is an ecologically and economically valuable species in subtropical regions of East Asia. Predicting the impact of climate change on potential distribution of Q. gilva can provide a scientific basis for the conservation and utilization of its genetic resources, as well as for afforestation. In this study, 74 distribution records of Q. gilva and nine climate variables were obtained after data collection and processing. Current climate data downloaded from WorldClim and future climate data predicted by four future climate scenarios (2040s SSP1-2.6, 2040s SSP5-8.5, 2060s SSP1-2.6, and 2060s SSP5-8.5) mainly based on greenhouse gases emissions of distribution sites were used in MaxEnt model with optimized parameters to predict distribution dynamics of Q. gilva and its response to climate change. The results showed that the predicted current distribution was consistent with natural distribution of Q. gilva, which was mainly located in Hunan, Jiangxi, Zhejiang, Fujian, Guizhou, and Taiwan provinces of China, as well as Japan and Jeju Island of South Korea. Under current climate conditions, precipitation factors played a more significant role than temperature factors on distribution of Q. gilva, and precipitation of driest quarter (BIO17) is the most important restriction factor for its current distribution (contribution rate of 57.35%). Under future climate conditions, mean temperature of driest quarter (BIO9) was the essential climate factor affecting future change in potential distribution of Q. gilva. As the degree of climatic anomaly increased in the future, the total area of predicted distribution of Q. gilva showed a shrinking trend (decreased by 12.24%–45.21%) and Q. gilva would migrate to high altitudes and latitudes. The research results illustrated potential distribution range and suitable climate conditions of Q. gilva, which can provide essential theoretical references for the conservation, development, and utilization of Q. gilva and other related species.

Carbon Sequestration in Sugarcane Plant-soil System as Influenced by Nutrient Integration Practices under Indo-Gangetic Plains of India

Sugarcane is a multi-purpose crop. The capability of sugarcane crop to sequestrate carbon into soil and plant is of great importance. Under this study the carbon sequestration in planted sugarcane and their rhizospheric soil under different nutrient management practices was assessed. As IPCC reported, that the rising temperature of earth surface resulted of GHGs emission which causes global warming. In order to stabilize the global temperature, the anthropogenic CO2 has to be mitigated to a significant level and the surplus atmospheric CO2 in plants and soil has to be sunk, under this circumstance, sugarcane cultivation plays pivotal role in utilising CO2 since it is a C4 plant having high efficiency of utilising CO2 during photosynthesis. There is another intervention might be enhancing the CO2 capture by changing the nutrient management practices which enhances chlorophyll synthesis by the way of increasing nitrogen efficiency in sugarcane. The different treatment composition enhances photosynthesis where more CO2 has been captured. Thus the sugarcane crop and rhizospheric soils act as important carbon sinks in decarbonisation of atmosphere that ultimately reduces carbon level and causes the global cooling. Soil Properties and Carbon Storage: The results showed that soil physical properties and chemical properties were significantly differed among treatments due to application of different organic amendments over control. Soil organic carbon (SOC) was analysed which ranges from 0.47 to 0.67%. The different organic amendments treatments had a considerable effect on soil bulk density and porosity with significant improvement in soil carbon storage. Plant Carbon Storage: The carbon stocks in different sugarcane plant parts, including roots, shoots and leaves were significantly different. The highest amount of carbon stock was found in leaves (877.08 kg ha-1) under T6 followed by roots (668.74 kg ha-1) in T2 and carbon stock in shoots (422.77 kg ha-1) in T5 showing that 30.41% and 107.58% more carbons were stored in the leaves as compared to the roots and shoots while in roots 58.18% more carbon stored in comparison to shoots. The total carbon storage in sugarcane biomass including aboveground parts and belowground part i.e. roots, in different treatment was significantly different. The mean value of carbon stored in the aboveground parts (leaves and stalks) was significantly higher (1239.65 kg ha-1) than that of underground plant part (621.73 kg ha-1) (roots). The results showed that the sugarcane farming practices have promising effect for carbon sequestration and consequently enhancing the mitigation of climate change impacts.

Modeling performances of maize cultivars under current and future climate scenarios in southern central Ethiopian rift valley

BackgroundIn southern central rift valley of Ethiopia, maize is an important crop because of its adaptation to wider agro-ecologies and higher yield potential. However, most cultivars were not parameterized to include in the database of Decision Support System for Agro-technology Transfer (DSSAT). As a result simulation of growth and yield of those cultivars was not possible under changing climate.MethodsTwo set of independent crop, management and soil data were used for calibration and validation of genetic coefficients of maize cultivars (BH-540, BH-546, BH-547, Shala and Shone) under condition of historic weather (1990–2020). Later, we simulated the growth and yield of maize using twenty multimodel climate ensembles across RCP 4.5 and 8.5 during early, medium and late century across Shamana, Bilate, Hawassa and Dilla clusters using DSSATv4.8 model.ResultsCultivars BH-540, BH-546, BH-547, Shala and Shone produced yields of 5.7, 5.4, 5.2, 6.9 and 7.4 t ha−1 with the corresponding error percentage of − 0.1, − 0.8, − 1.0, − 6.1 and 2.6%. The results of normalized root mean square were 1.14–4.2 and 3.0–3.9%, for grain yield during calibration and validation, respectively showing an excellent rating. The simulation experiment produced 5.4–9.2 t ha−1 for grain yield of maize cultivars across the study areas, which is likely to fall close to 63.3% by 2070 if right adaptation options are not introduced necessitating switch in cultivars and production areas.ConclusionsThere is critical need for reduction of GHGs emissions, generation of innovative adaptation strategies, and development of drought and heat stress tolerant maize cultivars. Hence, researchers and policy makers shall act with utmost urgency to embark with breeding programs that target climate change adaptation traits in maize crop.

CCS under Article 6 of the Paris Agreement

Article 6 of the Paris Agreement establishes the foundation for international carbon markets by allowing Parties to cooperate to achieve their nationally determined contributions (NDCs). The Paris Agreement also embeds the concept of ‘net zero’ by calling for a balance between anthropogenic emissions of GHGs and removals of GHGs by sinks to be reached in the latter part of this century. All signatory Parties therefore tacitly acknowledge that meeting the Agreement's ambitious climate change mitigation goals relies not only on deep cuts in anthropogenic GHG emissions, but also on the offsetting of residual, hard-to-abate, GHG emission sources through significant increases in carbon removal from the active climate system and the storage of CO2 in enhanced sinks and reservoirs. In these respects, Article 6 potentially offers a variety of routes to incentivize CO2 capture and storage (CCS) including through emissions trading but also more novel means of cooperation that focus more specifically on carbon storage and which could potentially address some of the challenges posed for CCS over the past 15 years or so. In order to assess the status and outlook for Article 6 with a focus on CCS activities, we define three potential models for cooperation and undertake a comparative evaluation against the key criteria of effectiveness, environmental integrity, commercial and financial viability, progression and policy performance. We conclude with some observations regarding the factors that may influence the likelihood of these different market models evolving over coming years.

Biomass-based energy potential from the oil palm agroindustry in Colombia: A path to low carbon energy transition

The energy valorization of biomass is critical to meeting the GHG mitigation goals and supporting the energy transition. The oil palm agroindustry, one of the fastest-growing sectors in Colombian agriculture, is characterized by low-efficiency technologies for bioenergy production. This study assessed four biomass-based energy generation scenarios considering the availability of biomass-based energy applications in backpressure or extraction-condensation turbines and anaerobic digestion systems in 28 palm oil mills, accounting for 68 % of Colombian crude palm oil production. Overall, the four scenarios can support 61–227 MW of electricity, coinciding with 0.4–1.5 % of the national installed capacity, while producing 44 to 222 kWh of surplus electricity per ton of fresh fruit bunch processed, with a levelized cost of electricity between 92.4 and 201.1 USD∙MWh−1 that highlights the economic feasibility. The emission of GHGs accounting for 22.2 to 55.1 gCO2eq per kWh could reduce the national GHG emissions by up to 2.1 %.

ESTIMATIONS OF GREEN HOUSE GASES EMISSIONS OF TURKEY BY STATISTICAL METHODS

The way of life, consumption habits, urbanization rate, type of energy production and increasing energy need with growing economies and population progressively promote the GHGs emissions to Earth’s atmosphere. GHGs consisting of CH4, N2O, CO2, H2O and HFCs cause the climate change, disrupting ecological balance, melting glaciers with global warming in the last decades. Therefore, the issues of future prediction and reduction of GHGs emissions became crucial for policy makers of Turkey and other countries under the international protocols and agreements. This article aims to present the prediction and 8-year future forecasting of CH4, N2O and CO2 emissions of Turkey using past annual data between years 1970 and 2018 with grey, autoregressive integrated moving average and double exponential smoothing models. Based on the results, the best prediction performance is reached by DES model followed by ARIMA and GM for all the emissions. MAPEs calculated from the available data and prediction by DES model from 1970 to 2018 are 0.285, 0.355 and 0.408 for CH4, N2O and CO2 in turn. DES future estimations of CH4, N2O and CO2 at 2026 year are determined as 50700 kiloton of CO2 eq., 38100 thousand metric ton of CO2 eq., and 512000 kilotons.

Installation and Performance Evaluation of a Solar Steam Cooking System for 1500 Students in the Hills– A Case Study

Community cooking is becoming costlier as the cost of cooking fuel is rising globally and impacting the environment by emitting greenhouse gasses which are responsible for global warming. India’s main cooking fuel is LPG which is being imported and is a depleting natural resource. The use of fossil fuels results in the emission of GHGs. This necessitates the harness of solar energy for community cooking. The campus receives daily horizontal solar radiation of 3.66-7.53 kWh/m2 which can be harnessed for cooking food. A solar steam cooking system consisting of 22 solar dishes has been installed at the university campus for 1500 students. This will generate heat of around 2.54 million Kcal/day and save LPG amounting to 33,600 kg/year while reducing the CO2 of 99,456 kg annually thereby mitigating climate change. Solar steam cooking will meet SDGs 7 and 13. The payback period for the solar steam cooking system will be 3 years. The cooking system meets Sustainable Development Goals7 & 13

Carbon footprints, mitigation effects and economic performance of dairy farm systems in Inner Mongolia

CONTEXTReducing the GHG emissions intensity of milk production has become a key sustainability challenge for the dairy sector. Addressing this challenge requires thorough understanding of the current GHG emission levels of individual farms, the practices influencing GHG emissions, and the economic trade-offs associated with reducing those emissions. OBJECTIVEQuantify the carbon footprint (CF) and economic performance of milk production in Inner Mongolia (the main dairy farming region in China), and understand the main contributing factors to them. The effects of potential mitigation options at dairy farm system level were evaluated. METHODS: Life cycle assessment methodology was used to analyze the CF of 15 dairy farms (with year-round cow housing and crop feeding) selected for different milk production levels, herd structures and diet composition. RESULTS AND CONCLUSIONSThe average CF per kg of fat and protein corrected milk (FPCM; after allocation to milk) was 2.3 kg carbon dioxide equivalents (CO2-eq) (1.5–3.4 kg CO2-eq). Emissions related to feed production, manure management and enteric fermentation were the top three GHG emission sources and contributed an average of 27% (5%–46%), 28% (19%–38%) and 18% (14%–25%), respectively, to total emissions. The average cost of the farm system per ton FPCM was USD 540 per year. Feed costs dominated at 70% of the total costs. The CF of milk was negatively correlated with profit per kg FPCM. Mitigation potential of the CF of dairy production for single mitigation strategies ranged from 2.3% to 20.0% compared with business as usual, and combined mitigation measures could reduce emissions by 48.3%. The most effective mitigation measures should focus on decreasing N-fertilizer use per ha for feed crop production and increasing feed crop yield, adjusting herd structure for milk productivity and using localized feed inputs. All mitigation measures had a positive impact on farm profit, except for the improved manure management (changing the farms using manure composting to a static compost system and changing natural storage to direct land application). Therefore, the combination of crop and dairy production and manure management offer the greatest potential to reduce the GHG emissions from Inner Mongolia dairy farm systems. Economic subsidies and extension of findings to farmers might encourage more rapid adoption of these technologies. SIGNIFICANCEThe insights from our study can provide guidance for defining and prioritizing mitigation strategies for dairy production to reduce GHGs emission in other rapidly developing countries and regions with crop-based housed-cow dairy production.

Recovery of Flared Natural Gas with High CO<sub>2</sub> Content Using SOFC CHP System: Feasibility Study for Neem-Field, Sudan

Flared natural gas emissions are one of the main sources of environmental pollution and global warming. To recover this gas, the presence of impurities like CO2 in high concentrations forces oil producers to escape from investing in such intensive processing. Several implementations of no flaring methods have been reported in the literature, however, there have been limited concerning the bulk-CO2 natural gases. This research developed an innovative idea for the use of the SOFC CHP system to recover flared bulk-CO2 associated gas of Neem-Field in Western Sudan. The exergy of the system and the performance of the SOFCs are investigated in this paper, in addition to environmental and economic analysis. The simulation (Cycle-Tempo©) results demonstrate that the proposed system can generate 1 MW electrical power and 0.068 MW thermal energy with efficiency approached 43.3% (based on LHV). The exergy analysis showed that 38% of system losses occurred in the air preheaters. Instead of conventional gas-burning, recovering the flared gas reduced the equivalent CO2 GHGs emissions by 80%. Overall, the novel solution found to be environmentally friendly, and economically appealing with a total capital investment estimated to be US$1.175 million and a cost of electricity (COE) of 4.07 cents per kWh.

An environmental impact assessment of Saudi Arabia's vision 2030 for sustainable urban development: A policy perspective on greenhouse gas emissions

Globally, countries are legitimizing actions to curtail the malevolent impacts of environmental degradation. This study examined the interaction between CO2 emissions and selected economic variables within the framework of Saudi Arabia's Vision 2030. The Autoregressive distributed lag model (ARDL) was used to analyze the long-run relationships and short-run dynamics between studied variables (1970–2020). The Mann-Kendall (MK) test revealed a significant (p < 0.05) positive increase of GHGs emissions from all sectors across the KSA. The highest increased were captured at the electricity and heat by 7345454.47 tonnes of carbon dioxide-equivalents/year (p < 0.05). On the hand, the ARDL model indicates that GDP, agriculture, industry, services, and oil production have short-term effects on the environment through CO2 emissions. Therefore, GDP, agriculture, services and oil production contribute to increases in CO2 emissions. While industry contributes to decrease in CO2 emissions. The ARDL model also showed that an increase in GDP of 1 percent increases CO2 emissions by 3.46 percent, while an increase in oil production of 1 percent increases CO2 emissions by 4.04 percent. However, an increase in industry of 1 percent decreases CO2 emissions by 7.25 percent. The output of this research has a policy implication for addressing environmental concerns in the country.

Uncovering the global ranking of greenhouse gases intensity, efficiency and structural transformation

This study incorporated the index decomposition analysis to drive the GHGs emissions intensity and separate the impact into true efficiency and structural transformation of economic activities on GHGs emissions. The global perspective is investigated in three aspects; (i) global groups of countries regarding income level, (ii) global countries bifurcated into geo-political regions and, (iii) hundred countries are taken to perform individual country level analysis, by taking 20 years (2000–2019) data. The hundred countries are ranked regarding GHGs intensity, efficiency and economic activities with respect to (i) for the latest year performance, (ii) twenty years average performance and, (iii) annual average reduction of GHGs emissions, comparable with base year 2000. Income-based countries groups explicate the improvement of GHGs intensity for HIC only and the economic transformation contributed to it. Efficiency index for all income groups while economic activities of LMIC, MIC and UMIC deteriorated the GHGs emissions. Global geo-political regions explicate the mixed pattern of GHGs intensity. Efficiency index is best for Azerbaijan and least for Uzbekistan. While ranking average GHGs emission reduction countries; Zimbabwe is the best and Qatar is the last country in the intensity list.