National CO2 Research Articles

Promoting inter-regional cooperation to reduce CO2 abatement cost in China

CO2 emissions reduction is a global challenge while the associated cost pressure presents a crucial issue. Within a country, each region, with different levels of abatement cost, may play different roles to achieve the national target of CO2 emissions reduction. Such heterogeneity could play a role in the cost efficiency of national CO2 emissions reduction, i.e. the minimum total abatement cost across the entire country. Previous models predominately focus on minimizing the total abatement cost, while the allocation of cooperative benefits is largely overlooked. We constructed a combined regional optimization and game model, i.e., the cooperative emission reduction model. The aim is to achieve the national carbon reduction target while reducing CO2 emissions at a minimum cost through inter-regional cooperation. In order to achieve cooperation, it is imperative to ensure that every participating region can benefit from cooperation. This study developed a cooperative emission reduction model based on the Shapley value method of game theory to determine the mechanism to distribute cooperation benefits amongst participating regions in fairness. Compared to the total costs before applying this model, 17.04 % ~ 33.62 % and 19.59 % ~ 24.62 % total CO2 abatement costs of China can be saved in 2025 and 2030, respectively. This method can be employed in other countries to assist policymakers to establish an appropriate goal for CO2 emission reduction, and formulate a compensation mechanism to promote inter-regional cooperation with fairness and minimum cost.

Analysing driving factors of India's transportation sector CO2 emissions: Based on LMDI decomposition method

India is the world's third-largest carbon dioxide (CO2) emitter, with the transportation sector accounting for most of this emission. Using the logarithmic-mean Divisia index (LMDI) decomposition method and Tapio decoupling, this study examines the driving factors and their relationship with economic growth for the Indian transportation sector. Transportation-related energy consumption is decomposed into six factors. From 2001 to 2020, CO2 emissions from the Indian transportation sector increased from 155.9 Mt to 368.2 Mt. Roadways produce 88% of all CO2 emissions. Energy systems, economic advancement, and population scale increase CO2 emissions, whereas energy performance and transportation form decrease. Transport advancement demonstrates both tendencies intermittently. CO2 emissions from Indian transportation exhibit a weak decoupling. The increasing demand for vehicles, reliance on conventional fuel, and increase in energy consumption indicate a positive correlation with the increase in the nation's CO2 emissions, while the transition from coal to electric locomotives and the increased use of electric vehicles offset the increase in emissions. In short, the government should update strategic sustainable transport policy measures and emphasize renewable energy. This study will assist policymakers in formulating robust sustainable transportation policies.

A Drag Reduction Study on the Aerodynamics of the Irish Taxi Sign

This comprehensive study focused on the standard taxi sign used in Ireland and its impact on drag production, fuel expenses, and CO2 emissions. Experimental analysis revealed that the conventional taxi sign significantly increased drag, especially when mounted on streamlined vehicles such as saloon cars, due to flow separation issues on the rear roof and rear windshield. Longitudinal reorientation of the sign offered a 14-fold reduction in drag increase compared to the traditional placement. It was found that positioning the sign in the middle of the roof offered the greatest fuel efficiency. Furthermore, the study estimated that implementing longitudinal repositioning on all Irish taxi signs could save drivers approximately EUR 832 per year and reduce national CO2 emissions by a substantial 22,464 tonnes annually. Comparative analyses with international taxi signs demonstrated that the Irish sign had significantly larger drag contributions, emphasizing the need for improved aerodynamics. To address the inherent drag issue, the study explored novel appendable devices and proposed alternative taxi sign designs. Among the tested solutions, a magnet-mounted front ramp proved the most effective, reducing total drag by nearly 30%. Additionally, a motorized flip-up taxi sign design demonstrated a remarkable 40% reduction in drag. Finally, a newly proposed taxi sign design, featuring longitudinal positioning and pointed triangular front and rear faces, resulted in a minimal 4.3% increase in vehicle drag compared to the baseline car.

Storing Carbon in Forest Biomass and Wood Products in Poland—Energy and Climate Perspective

Huge amounts of carbon being sequestered in forest ecosystems make them an important land carbon sink at the global scale. Their ability to withdraw carbon dioxide (CO2) from the atmosphere, whose concentration is gradually increasing due to anthropogenic emissions, renders them important natural climate-mitigation solutions. The urgent need for transition from high to zero net emission on country, continental, and global scales, to slow down the warming to an acceptable level, calls for the analysis of different economic sectors’ roles in reaching that ambitious goal. Here, we examine changes in CO2 emission and sequestration rates during recent decades focusing on the coal-dominated energy sector and Land Use, Land-Use Change, and Forestry (LULUCF) as well as wood production at the country level. The main purpose of the presented study is to examine the potential of storing carbon in standing forest biomass and wood products in Poland as well as the impact of disturbances. The ratio of LULUCF absorption of CO2 to its emission in Poland has ranged from about 1% in 1992 to over 15% in 2005. From a climate-change mitigation point of view, the main challenge is how to maximize the rate and the duration of CO2 withdrawal from the atmosphere by its storage in forest biomass and wood products. Enhancing carbon sequestration and storage in forest biomass, via sustainable and smart forestry, is considered to be a nature-based climate solution. However, not only forests but also wood-processing industries should be included as important contributors to climate-change mitigation, since harvested wood products substitute materials like concrete, metal, and plastic, which have a higher carbon footprint. The energy perspective of the paper embraces two aspects. First, CO2 sequestration in forests and subsequently in harvested wood products, is an effective strategy to offset a part of national CO2 emissions, resulting largely from fossil fuel burning for energy-production purposes. Second, wood as biomass is a renewable energy source itself, which played an important role in sustaining energy security for many individual citizens of Poland during the unusual conditions of winter 2022/2023, with a scarce coal supply.

Is there a Green Dividend of National Redistribution?

CO2 emissions are disproportionately caused by more affluent consumers. In the political debate, this fact has triggered the demand for income redistribution and wealth taxes not only to reduce inequality but also to reduce CO2 emissions. This paper calculates the possible size of a green dividend, i.e., a reduction in total national CO2 emissions, of redistribution in 26 countries and concludes that, for most EU countries, it is negative if the redistribution is efficient, in the sense that it keeps average incomes constant. If the redistribution introduces inefficiencies that lead to total income losses, the negative green dividend, otherwise associated with additional redistribution, may be avoided.

Multi-scale observations of mangrove blue carbon ecosystem fluxes: The NASA Carbon Monitoring System BlueFlux field campaign

The BlueFlux field campaign, supported by NASA’s Carbon Monitoring System, will develop prototype blue carbon products to inform coastal carbon management. While blue carbon has been suggested as a nature-based climate solution (NBS) to remove carbon dioxide (CO2) from the atmosphere, these ecosystems also release additional greenhouse gases (GHGs) such as methane (CH4) and are sensitive to disturbances including hurricanes and sea-level rise. To understand blue carbon as an NBS, BlueFlux is conducting multi-scale measurements of CO2 and CH4 fluxes across coastal landscapes, combined with long-term carbon burial, in Southern Florida using chambers, flux towers, and aircraft combined with remote-sensing observations for regional upscaling. During the first deployment in April 2022, CO2 uptake and CH4 emissions across the Everglades National Park averaged −4.9 ± 4.7 μmol CO2 m−2 s−1 and 19.8 ± 41.1 nmol CH4 m−2 s−1, respectively. When scaled to the region, mangrove CH4 emissions offset the mangrove CO2 uptake by about 5% (assuming a 100 year CH4 global warming potential of 28), leading to total net uptake of 31.8 Tg CO2-eq y−1. Subsequent field campaigns will measure diurnal and seasonal changes in emissions and integrate measurements of long-term carbon burial to develop comprehensive annual and long-term GHG budgets to inform blue carbon as a climate solution.

Temporal and spatial analysis of anthropogenic mercury and CO2 emissions from municipal solid waste incineration in China: Implications for mercury and climate change mitigation

The contribution of municipal solid waste incineration (MSWI) to anthropogenic mercury and CO2 emissions have become increasingly important over the past decade. This study developed an inventory of anthropogenic mercury emissions and CO2 emissions during the period of 2014–2020, of MSWI process in China using a bottom-up inventory at the plant level. Overall, national MSWI anthropogenic mercury emissions increased from 2014 to 2020 by province. It was estimated that total 8321.09 kg of anthropogenic mercury emissions from 548 MSWI plants were scattered in 31 provinces of mainland China in 2020. The average intensity of mercury emission in China was 0.06 g·t−1 in 2020, which was much lower than the pre-2010 level. Furthermore, the increased CO2 emission generated by MSWI from 2014 to 2020 is 1.97 times. Anthropogenic mercury emissions and CO2 emissions were concentrated mainly in developed coastal provinces and cities. The general uncertainty of national mercury emissions and CO2 emissions was estimated to be −123% to 323% and −130% to 335%, respectively. Furthermore, future emissions were predicted from 2030 to 2060 based on different scenarios of the independent and collaborative effects of control proposals, the results indicate that the enhancement of advanced air pollution control technologies and effective management of MSWI represent pivotal factors in realizing future reductions in CO2 and mercury emissions. The findings will supplement those for mercury and CO2 emissions, and be useful for relevant policy-making and to improve urban air quality, as well as human health.

Assessing China's Scope 2 CO2 emissions and mitigation pace from space

China is committed to CO2 emissions peaking by 2030 and carbon neutrality by 2060. This study aims to explore a method to measure its progressing pace largely independently for providing feedback. With OCO-2 carbon satellite and NPP-VIIRS night-time light data, we develop and apply a satellite-based approach to estimate provincial Scope 2 CO2 emissions, which refers to those emissions stemming from electricity trade, from 2015 to 2020. Our results can reflect the spatial disparity of electricity trade and energy structure across China. Furthermore, a Carbon Mitigation Index (CMI) is defined, through combining information from carbon and night-time light satellites, to measure China's national and provincial CO2 mitigation pace toward carbon neutrality, which indicates the composite progress of various key drivers, including energy transition, electrification, net electricity import, socio-economic development, and energy efficiency. Because the CMI requires only satellite data but not bottom-up statistics in its application, it offers an opportunity for external assessment from space.

Carbon Monitor Europe near-real-time daily CO2 emissions for 27 EU countries and the United Kingdom

With the urgent need to implement the EU countries pledges and to monitor the effectiveness of Green Deal plan, Monitoring Reporting and Verification tools are needed to track how emissions are changing for all the sectors. Current official inventories only provide annual estimates of national CO2 emissions with a lag of 1+ year which do not capture the variations of emissions due to recent shocks including COVID lockdowns and economic rebounds, war in Ukraine. Here we present a near-real-time country-level dataset of daily fossil fuel and cement emissions from January 2019 through December 2021 for 27 EU countries and UK, which called Carbon Monitor Europe. The data are calculated separately for six sectors: power, industry, ground transportation, domestic aviation, international aviation and residential. Daily CO2 emissions are estimated from a large set of activity data compiled from different sources. The goal of this dataset is to improve the timeliness and temporal resolution of emissions for European countries, to inform the public and decision makers about current emissions changes in Europe.

Inequality and its driving forces in residential CO2 emission: Perspective of energy use pattern

The complex geographic situation and various development levels have created differences in residential energy use patterns, inequalities problems in residential CO2 emissions among regions present a dilemma for policymakers. Therefore, this study investigated residential CO2 emissions inequality and its driving factors to provide empirical support for the allocation of regional emission reduction quotas. Using the residential data of provincial scale in China during 1997–2019, this research presents a complete decomposition from the perspective of energy use pattern and income disparities. The findings showed that the national residential CO2 emissions inequality decreased between 1997 and 2008, and then stabilized. The energy intensity effect was the main effect that decreased the inequality, while the energy use pattern increased it. For most inland regions, the within-group inequity was mainly due to energy input per income, while the inequality of coastal regions could be explained by the differences in income per capita. Regarding energy use inequality, the energy intensity effect was the main reason behind the inequality in heat and fuel energy use, but it had a smaller influence on the electricity consumption inequality. The Kaya-Theil decomposition model could be applied to investigate regional inequality in emissions, and the results help to design targeted differentiate mitigation measures for regional residential sector.

A Study of Grid-Connected Residential PV-Battery Systems in Mongolia

For national energy capacity improvement and CO2 emission reductions, Mongolia has focused its attention on grid-connected residential PV systems. Due to the feed-in tariff (FIT), the aggregated residential PV systems are expected to increase with the PV penetration level. Currently, there is no power injection limitation in Mongolia. A new policy for the PV penetration level of residential PV systems needs to be developed. This study analyzed the techno-economic performances of distributed PV-battery systems, considering PV generation, the historical load demand, and the tariff structure. We studied the performances of 40 combinations of PV sizes (2 kW–9 kW) and battery capacities (4.4 kWh, 6.6 kWh, 10 kWh, 12 kWh, and 15 kWh) to find feasible system sizes. The aggregated PV-battery systems in a low-voltage (LV) distribution system located in Ulaanbaatar, Mongolia, are also discussed. The results show that six combinations satisfied the technical and economic requirements. The maximum profit was determined to be an NPV of 1650 USD with a 9-year payback period using combination 3 (6 kW PV and 6.6 kWh battery capacity). Combination 6 (8 kW PV and 15 kWh battery capacity) shows that the energy management strategy for residential houses with battery storage has the potential to increase the installed capacity of PV systems without voltage violence in the LV network. For the distributed PV-battery storage system (BSS), the environmental analysis indicates that CO2 and SO2 emissions were reduced by 3929 t/year and 49 t/year, respectively. The findings obtained from this analysis will be used for power system planning.

Review of Policies for Indonesia’s Electricity Sector Transition and Qualitative Evaluation of Impacts and Influences Using a Conceptual Dynamic Model

Indonesia’s final energy demand is projected to increase by 70% in the next decade, with electricity expected to account for 32%. The increasing electricity demand poses a potential threat to national emissions reduction targets since fossil fuels generated 86% of the electricity in 2018, associated to 50% of the national CO2 emissions. Indonesia plans to reduce its CO2 emissions by 29% by increasing the total electricity generated from renewables, using a set of market-based and regulatory policies. However, economic, social, and environmental issues may arise from the widespread adoption of renewable energy. This study explores the economic, social, and environmental effects of renewable energy policies in the electricity sector. Our work presents an advance over previous studies that attempted to understand the electricity sector energy transition from a system perspective by exploring the structural feedback between it and economic, energy, and environmental systems. This enables the assessment of different energy policies using more macro indicators, which further emphasize the novelty of our work. A combination of system dynamics modelling and a policy analysis framework was applied to explore these issues. Our study proposes a dynamic hypothesis that the price of energy increases over time, in the absence of substitution, becoming a limiting factor in the transition to renewables in the electricity sector. The fiscal budget was found to be a bottleneck for renewable energy adoption in the electricity sector in Indonesia. We found that a fossil fuel depletion premium could be a potential supporting policy to enable the smooth phasing-out of fossil fuels and support a sustainable energy transition.

Carbon Mitigation and Environmental Co-Benefits of a Clean Energy Transition in China's Industrial Parks.

Industrial parks are emerging priorities for carbon mitigation. Here we analyze air quality, human health, and freshwater conservation co-benefits of decarbonizing the energy supply of 850 China's industrial parks. We examine a clean energy transition including early retirement of coal-fired facilities and subsequent replacement with grid electricity and onsite energy alternatives (municipal solid waste-to-energy, rooftop photovoltaic, and distributed wind power). We find that such a transition would reduce greenhouse gas emissions by 41% (equal to 7% of 2014 national CO2 equivalent emissions); emissions of SO2 by 41%, NOx by 32%, and PM2.5 by 43% and freshwater consumption by 20%, relative to a 2030 baseline scenario. Based on modeled air pollutant concentrations, we estimate such a clean energy transition will result in ∼42,000 avoided premature deaths annually due to reduced ambient PM2.5 and ozone exposure. Costs and benefits are monetized including technical costs of changes in equipment and energy use and societal benefits resulting from improvements in human health and reductions of climate impacts. We find that decarbonizing industrial parks brings annual economic benefits of US$30-156 billion in 2030. A clean energy transition in China's industrial parks thus provides both environmental and economic benefits.

Uncovering and Filtering Industrial Symbiosis Networks for Carbon Dioxide Utilization in Trinidad and Tobago

The emission source profile of the small island developing State of Trinidad and Tobago (T&T) is unique amongst high national CO2 emitters per unit of GDP. To consider appropriate options for sustainably reusing CO2 in an industrial symbiosis network (ISN), a simple enterprise input-output model of CO2 exchanges between representative plants in a petrochemical cluster at the Point Lisas Industrial Estate in T&T was created. Then multi-objective optimization (MOO) was performed, so that both CO2 emissions and levelized transportation costs would be enhanced. Initial benchmarking uncovered the potential to reuse 17% of the process CO2 emissions in chemical manufacturing on the representative petrochemical network. Next, the effect of adding a CO2-reusing propylene carbonate plant to the ISN was examined. To determine how to add the propylene carbonate plant, MOO was reapplied to an updated network model, to filter all the possible ISNs. These MOO results suggest the addition of a CO2-reusing plant would increase the mass of CO2 reused in the ISN by 6.3%. Thus, eco-connectance, which is a measure of the level of IS, would be increased by 35%. The proposed changes could improve multiple Sustainable Development Goal (SDG) indicators concomitant with SDGs 8, 9, 12 and questionably 13.

Environmental Sustainability of Bricks in an Emerging Economy: Current Environmental Hotspots and Mitigation Potentials for the Future

Clay-fired bricks are widely used in emerging economies mainly because of the unavailability of higher-grade construction and building materials; however, they are associated with significant social and environmental damage. The environmental burdens associated with the fuels and materials required for brick production are huge, as they have both direct and indirect effects along supply chains. This study aimed to assess the environmental footprints of brick production along supply chains, focusing on relevant environmental issues in brick production: carbon dioxide emissions, water consumption, and land use. We demonstrate that fuelwood consumption constitutes a major share of the carbon and water footprints, whereas built-up land for brick drying dominates the major effect of land use. Our expansion of the ecological footprint method enables a comparison of the effects of three different environmental issues with the same land area dimension, which reveals the relative severity of carbon dioxide emissions that account for up to 20% of the national CO2 inventory. For the potential reduction in the environmental footprint of brick production, scenario analysis showed a substantial reduction by replacing clay-fired bricks with concrete bricks. The shift to alternative materials, together with mitigation measures for brick production, can effectively alleviate the environmental pressures of construction materials in future emerging economies.

Near-real-time global gridded daily CO2 emissions 2021

We present a near-real-time global gridded daily CO2 emissions dataset (GRACED) throughout 2021. GRACED provides gridded CO2 emissions at a 0.1° × 0.1° spatial resolution and 1-day temporal resolution from cement production and fossil fuel combustion over seven sectors, including industry, power, residential consumption, ground transportation, international aviation, domestic aviation, and international shipping. GRACED is prepared from the near-real-time daily national CO2 emissions estimates (Carbon Monitor), multi-source spatial activity data emissions and satellite NO2 data for time variations of those spatial activity data. GRACED provides the most timely overview of emissions distribution changes, which enables more accurate and timely identification of when and where fossil CO2 emissions have rebounded and decreased. Uncertainty analysis of GRACED gives a grid-level two-sigma uncertainty of value of ±19.9% in 2021, indicating the reliability of GRACED was not sacrificed for the sake of higher spatiotemporal resolution that GRACED provides. Continuing to update GRACED in a timely manner could help policymakers monitor energy and climate policies’ effectiveness and make adjustments quickly.

Drivers in carbon dioxide, air pollutants emissions and health benefits of China's clean vehicle fleet 2019–2035

Clean vehicle fleet will greatly benefit air quality and climate change mitigation. Here, we employ an integrated model to systematically investigated the contribution of combined clean vehicle policies to “emissions, exposure, and health benefits” from a regional perspective 2019–2035 in China. We find that driven by clean vehicle polices, the national vehicle CO2 will likely to peak around 2028 with about 1327 million tons, and then reduce by 7.8% from 2028 to 2035. The developed region will peak CO2 before 2030, while the developing region probably peak after 2030. In general, most air pollutants emissions from vehicles will decrease, subsequently leading to obvious PM2.5 and O3 exposure decrease. About 68 thousand PM2.5 related and 33 thousand O3 related deaths will be avoided 2019–2035 nationwide. Note that the health benefits are unequal, with higher PM2.5-O3 related excess deaths be avoided per 100000 in developed region than developing region. Besides, results show that emission standard upgrade contributes largest to emission reduction and related health benefits, followed by electric vehicles, road-to-railways and waterways, and fuel consumption regulation in general. This work is able to provide valuable information for policy makers to collaboratively reduce CO2, air pollutants and premature deaths in China and other developing countries.

Per capita CO2 emission inequality of China's urban and rural residential energy consumption: A Kaya-Theil decomposition

With the increasing affluence, the differences in CO2 emission between urban and rural residential sectors are remarkable and show an increasing trend. In case of China, residential sector accounts for a substantial share of the national CO2 emission, bringing greater pressure to achieve the goal of carbon peak. Analyzing the emission inequality trend and its drivers is essential for formulating effective CO2 emission reduction policies. However, the existing literature lacks relevant analysis from the viewpoint of urban-rural disparity. Hence, this study decomposes the CO2 emission inequality of China's urban and rural residential consumption into four factors by combining the Theil index and Kaya decomposition. The results suggest that, in 2005–2020, the per capita CO2 emission of rural residential consumption increased to a higher extent than those of urban households, with large differences in spatial distribution. Decomposition of the per capita CO2 emission inequality for residential sector shows that the primary source is the inequality within the groups, mainly from the urban intra-group inequality. Based on the static decomposition, energy intensity appears as the main factor of urban–rural inequality. The dynamic decomposition shows that there have been differences in the factors of the change in the Theil index between urban and rural areas across sub-periods.

Vegetation Uptake of Carbon Dioxide on Peat Swamp Forests Based on The Growth Rate

This study aims to identify the type composition and estimate the potential for biomass and carbon deposits as well as carbon dioxide (CO2) uptake of peat swamp forest vegetation based on the growth rates (seedling, sapling, pole, tree). The estimation of potential deposits of vegetation biomass is calculated by destructive and non-destructive methods. The potential for carbon impedance is calculated using the formula Bof National Standardization (2011) and CO2 absorption with the IPCC formula (2006). The results showed that the number of vegetation types found was 44 types from 25 families. Stake-level vegetation is the most common type found compared to seedlings, poles, and trees. Tree-level vegetation is dominated by Cratoxylon arborescent BI, Combretocarpus rotundatus pole level, and Stemonurus secundiflorus Blume stake level., the seedling level of Anacolosa frutescens. The potential for biomass, carbon deposits, and CO2 uptake of peat swamp forest vegetation is 179.976 tons/ha; 84.588 tons C/ha; 310.442 tons CO2/ha, respectively. Tree-level vegetation has the highest deposits of biomass and carbon as well as CO2 uptake compared to seedling, sapling, and pole levels. Youth-level vegetation (seedlings, sapling, pole) in peat swamp forests has great potential in storing biomass, carbon, and CO2 uptake in the long term.
 Keywords: biomass, carbon, carbon dioxide uptake, peat swamp forest, vegetation

Interval-parameter bi-level programming for energy system management under uncertainty: Towards a deep-decarbonized and sustainable future in China

To reach the goal of carbon-neutral society, synergistic approaches based on mathematical models that are capable of planning energy system associated with complex uncertainty and hierarchical structure are desired. In this study, an interval-parameter bi-level programming (IBP) method that is effective for solving hierarchical decision-making problems with conflict objectives and uncertainty is developed. Then, an IBP based China's energy system model (abbreviated as IBP_CES) is formulated for mainland China during 2021–2050, where the higher-level objective of minimizing carbon dioxide (CO2) emission is given priority, following by the lower-level objective of minimizing system cost. Results from IBP_CES show that, although China's energy supply would still rely heavily on fossil fuels, the share of coal would decrease to 33.9% by 2050. Results also disclose that the national CO2 emission would reach the peak value during 2026-2030 and then decline rapidly due to development of renewable energy and promotion of carbon-treatment technology which is beneficial for government to achieve carbon neutrality goals. In addition, compared to the traditional single-level model, CO2 emission from IBP_CES can decrease by 5.9%, demonstrating that IBP_CES is more superior in energy system decarbonization. The findings can help decision makers to well understand the interactions and tradeoffs between climate mitigation and economic development, and provide effective information on clean, sustainable and deep-decarbonized development strategies.