Carbon Dioxide Equivalent Emissions Research Articles

Analysis and Assessment of the Building Life Cycle. Indicators and Tools for the Early Design Stage

Construction is a crucial sector in terms of worldwide environmental impacts. Building material production along with transport and demolition are no exception, because in the last decades, they have constantly increased their carbon dioxide (CO2) emissions. Actions and initiatives are therefore important to tackle the relationship between buildings and climate change. Particularly, it is necessary to develop Life Cycle Assessment (LCA) tools useful to calculate the environmental impact of buildings and to make them accessible to designers and stakeholders acting in the building sector. The article aims to contribute to the international debate about environmental assessment indicators for buildings and the simplified LCA based tools. The Embodied Energy (EE) and the Embodied Carbon (EC) have been investigated. The former, related to primary energy content; the latter, associated with the equivalent carbon dioxide emissions. EE and EC have been used as indicators for the development of a calculation tool named EURECA, for assessing the environmental impact of the building over its life cycle, as defined by the EN 15978:2011 standard. The Solar Decathlon Latin America and Caribbean’s house designed and built by an international academic team has been an opportunity to check the indicators and the tool’s effectiveness.

Ecological vulnerability of the chondrichthyan fauna of southern Australia to the stressors of climate change, fishing and other anthropogenic hazards

AbstractWe develop a potentially widely applicable framework for analysing the vulnerability, resilience risk and exposure of chondrichthyan species to all types of anthropogenic stressors in the marine environment. The approach combines the three components of widely applied vulnerability analysis (exposure, sensitivity and adaptability) (ESA) with three components (exposure, susceptibility and productivity) (ESP) of our adaptation of productivity–susceptibility analysis (PSA). We apply our 12‐step ESA‒ESP analysis to evaluate the vulnerability (risk of a marked reduction of the population) of each of 132 chondrichthyan species in the Exclusive Economic Zone of southern Australia. The vulnerability relates to a species’ resilience to a spatial (or suitability) reduction of its habitats from exposure to up to eight climate change stressors. Vulnerability also relates to anthropogenic mortality added to natural mortality from exposure to the stressors of five types of fishing and seven other types of anthropogenic hazards. We use biological attributes as risk factors to evaluate risk related to resilience at the species or higher taxonomic level. We evaluate each species’ exposure to anthropogenic stressors by assigning it to one of six ecological groups based on its lifestyle (demersal versus pelagic) and habitat, defined by bathymetric range and substrates. We evaluate vulnerability for 11 scenarios: 2000–2006 when fishing effort peaked; 2018 following a decade of fisheries management reforms; low, medium and high standard future carbon dioxide equivalent emissions scenarios; and their six possible climate–fishing combinations. Our results demonstrate the value of refugia from fishing and how climate change exacerbates the risks from fishing.

Travelling to Bundesliga matches: the carbon footprint of football fans

ABSTRACT The purposes of this study were to estimate the carbon footprint caused by football fans travelling to Bundesliga matches (first division) in Germany in the 2018/19 season, to analyse determinants of seasonal carbon footprint, and to identify fan clusters based on travel behaviour. A nationwide online survey of football fans was conducted (n = 539) asking respondents to report their match-related travel behaviour. The average seasonal carbon footprint of a Bundesliga fan amounted 311.1 kg of carbon dioxide equivalent emissions (CO2-e), with car travel accounting for 70% of the emissions. The aggregate carbon footprint of all fans for the whole Bundesliga season was 369,765.2 t CO2-e. Buying out of these carbon emissions would cost over €9.2 million in total. The regression results revealed that club membership and commitment to favourite club significantly increased fans’ carbon footprint. The choice of favourite Bundesliga club also predicted carbon footprint, with fans of FC Bayern Munich and RB Leipzig producing a significantly higher carbon footprint than fans of Borussia Dortmund. The segmentation of Bundesliga fans by their travel behaviour identified three distinct clusters: Devoted travellers (19%), home fans (30%) and casual visitors (51%). These clusters differed significantly in terms of emissions per kilometre travelled, car use versus public transport, club membership, fan commitment, environmental consciousness, education and age. The findings have practical implications for policy makers, Bundesliga officials and club authorities, and can serve as a basis for initiatives to reduce carbon dioxide emissions in professional team sports.

Life Cycle Cost Analysis of a Single-Family House in Sweden

The objective of this paper was to explore long-term costs for a single-family house in Sweden during its entire lifetime. In order to estimate the total costs, considering construction, replacement, operation, and end-of-life costs over the long term, the life cycle cost (LCC) method was applied. Different cost solutions were analysed including various economic parameters in a sensitivity analysis. Economic parameters used in the analysis include various nominal discount rates (7%, 5%, and 3%), an inflation rate of 2%, and energy escalation rates (2–6%). The study includes two lifespans (100 and 50 years). The discounting scheme was used in the calculations. Additionally, carbon-dioxide equivalent (CO2e) emissions were considered and systematically analysed with costs. Findings show that when the discount rate is decreased from 7% to 3%, the total costs are increased significantly, by 44% for a 100-year lifespan, while for a 50 years lifespan the total costs show a minor increase by 18%. The construction costs represent a major part of total LCC, with labor costs making up half of them. Considering costs and emissions together, a full correlation was not found, while a partial relationship was investigated. Results can be useful for decision-makers in the building sector.

Environmental emissions reduction of a preoperative evaluation center utilizing telehealth screening and standardized preoperative testing guidelines

The healthcare sector is responsible for 8.5% of greenhouse gas (GHG) emissions in the United States. To prevent catastrophic effects of climate change, urgent reductions in GHG emissions are needed. Unnecessary preoperative testing and clinic visits contribute to excessive utilization of healthcare resources and patient travel, and addressing them may help reduce emissions. A retrospective cross-sectional analysis of GHG emissions associated with pre- and post- implementation of a novel telehealth preoperative evaluation process was performed on 298 American Society of Anesthesiologists Class I-III patients undergoing elective spine surgery at Yale New Haven Hospital. Electronic health records were evaluated to determine patient health status and necessary or unnecessary preoperative tests and clinic visits. Life cycle assessment and U.S. EPA GHG calculator were used to estimate carbon dioxide equivalent (CO2e) emissions from preoperative testing, clinic visits, and patient commuting. GHG emissions were reduced by 8.09 kg CO2e (9.6%) per patient, from 84.52 kg CO2e pre-intervention to 76.43 kg CO2e post-intervention (p = 0.019). The largest reduction, 14.71 kg CO2e, stemmed from fewer in-person clinic evaluations. An additional reduction of 18.07 kg CO2e per patient would have been possible if clinic performance were optimized (only necessary testing performed), resulting in a total reduction of 26.16 kg CO2e (31%). A preoperative clinic using established testing guidelines and telehealth can reduce environmental emissions. With more than 40 million annual surgeries nationwide, concerted effort to reduce unnecessary testing and visits should help curtail healthcare GHG emissions.

Emissions assessment of bike sharing schemes: The case of Just Eat Cycles in Edinburgh, UK

Transport accounts for 40 % of global emissions, 72 % of which comes from road transport, and private cars are responsible for 60 % of road transport emissions. In cities, self-service bike sharing systems are quickly developing and are intended to offer an alternative and cleaner mode of transport than the car. However, the sustainability of such schemes is often taken as a given, rather than thoroughly evaluated. To address this gap, in this paper we undertake a life cycle assessment (LCA) of a public self-service bike sharing system in the city of Edinburgh, UK, modelling the production, operation and disposal elements of the system, but discounting additional food intake by users. Our results show that the bike sharing scheme is saving carbon dioxide equivalent emissions compared to the modes of transport by which its users previously travelled, but it is essential to optimize rebalancing operations and to manufacture bikes as near as possible to the point of use to further reduce carbon emissions; and that the overall emissions impacts of the scheme are critically dependent on how public transport providers respond to reductions in demand as users shift trips to bikeshare, since most trips transfer from walk and public transport, not private car. The policy implications for authorities seeking to use BSS as a GHG reduction intervention are not straightforward.

Lockdown Measures Which Reduced Greenhouse Gas Emissions With Little Negative Impact on Quality of Life.

Lockdown measures in response to the new Covid‐19 virus have caused the largest ever fall of annual greenhouse gas emissions. A key question that we attempt to answer in this study is which, if any, of these measures can be productively encouraged post‐lockdown in efforts to sustain at least part of this reduction in emissions. Sweden is uniquely suited for our study because the voluntary nature of lockdown in Sweden allowed us to assess the level of compliance to recommendations and its effects on greenhouse gas emissions. First, we assessed the change of perceived quality of life (QOL) among 746 individuals from Stockholm region due to adhering to lockdown measures. Second, we calculated the associated change of annual per capita greenhouse emissions. We found that avoiding travel for work, avoiding purchasing, and avoiding restaurants had the least negative effect on QOL, and at the same time the largest positive effect on carbon dioxide equivalent (CO2e) emission reductions. We conclude that these are potential leverage points for stimulating behavioral change that has a positive climatic impact.

Decarbonization of Residential Building Energy Supply: Impact of Cogeneration System Performance on Energy, Environment, and Economics

Electrical and thermal loads of residential buildings present a unique opportunity for onsite power generation, and concomitant thermal energy generation, storage, and utilization, to decrease primary energy consumption and carbon dioxide intensity. This approach also improves resiliency and ability to address peak load burden effectively. Demand response programs and grid-interactive buildings are also essential to meet the energy needs of the 21st century while addressing climate impact. Given the significance of the scale of building energy consumption, this study investigates how cogeneration systems influence the primary energy consumption and carbon footprint in residential buildings. The impact of onsite power generation capacity, its electrical and thermal efficiency, and its cost, on total primary energy consumption, equivalent carbon dioxide emissions, operating expenditure, and, most importantly, thermal and electrical energy balance, is presented. The conditions at which a cogeneration approach loses its advantage as an energy efficient residential resource are identified as a function of electrical grid’s carbon footprint and primary energy efficiency. Compared to a heat pump heating system with a coefficient of performance (COP) of three, a 0.5 kW cogeneration system with 40% electrical efficiency is shown to lose its environmental benefit if the electrical grid’s carbon dioxide intensity falls below 0.4 kg CO2 per kWh electricity.

Predicting embodied carbon emissions from purchased electricity for United States counties

Predicting the embodied scope 3 carbon dioxide equivalent (CO2e) emissions from purchased electricity for end users in the United States is challenging due to electricity transmission within interconnected power grids. Existing methods only focus on large aggregation areas, thereby ignoring potentially significant emission factor (EF) variations, so this study proposes a novel method to translate the CO2e emissions from the balancing authority (BA)-level to the county-level by utilizing explicit finite-difference theory for electricity flow predictions, and then employing economic input–output theory to evaluate the scope 3 embodied lifecycle CO2e emissions. Results show that the generation-based EFs at the BA-level range from 0.007 to 0.905 MT-CO2e/MWh with a mean value of 0.400 MT-CO2e/MWh and a standard deviation of 0.229 MT-CO2e/MWh. The consumption-based EFs at the BA-level range from 0.008 to 0.836 MT-CO2e/MWh with a mean value of 0.378 MT-CO2e/MWh and a standard deviation of 0.019 MT-CO2e/MWh. Results also show that sixteen BA consumption-based EFs deviate by more than 20% compared to their generation-based EFs, which indicates the significance of accounting for electricity interchanges in emissions quantification processes. A larger range of possible consumption-based EFs is revealed at the county-level: 0.007 to 0.902 MT-CO2e/MWh, with a mean value of 0.452 MT-CO2e/MWh and a standard deviation of 0.123 MT-CO2e/MWh. Results also indicate significant variations in EFs of counties within each BA: 20 BAs have county-level EFs range greater than 0.1 MT-CO2e/MWh, 13 BAs have county-level EFs range greater than 0.2 MT-CO2e/MWh and 6 BAs have county-level EFs range beyond 0.3 MT-CO2e/MWh.

Properties of concrete with high volumes of unprocessed coarser fly ash and nanosilica

The limitation of fly ash as a cement substitute in concrete is often low due to its slow rate of strength development. The use of unprocessed coarser siliceous fly ash is also negligible. An attempt was made to produce a structural-grade concrete using a high volume of unprocessed coarser fly ash and colloidal nanosilica that was curable at ambient conditions. The fly ash content in the trial mixes varied from 50 to 70%. The temperature of fresh mixes during early age indicated that adding nanosilica accelerated the rate of hydration. Also, substantial improvements in early- and later-age compressive, split tensile and flexural strengths; modulus of elasticity; and stress–strain characteristics were observed for mixes with nanosilica. The compressive strength test results were corroborated with the inferences made from scanning electron microscopy and differential thermogravimetric analysis of the hardened cementitious pastes. The material cost of the mixes with nanosilica was found to be in a range similar to that of an ordinary Portland cement concrete, and the carbon dioxide equivalent emission of such concretes was 45–65% lower. It was concluded that with the addition of 3% colloidal nanosilica, it is possible to prepare a structural-grade concrete using unprocessed coarser siliceous fly ash that is curable at ambient conditions and has significantly improved early-age strength and also high later-age strength, while at the same time achieving sustainability and favourable cost benefits.

Carbon capturing for emissions reduction at building level: A market assessment from a building management perspective

Global climate change is a key concern in today’s world, especially with the growth of population and industrial activities. One of the biggest sources of climate change is anthropogenic greenhouse gas emissions. In Canada, buildings are the third largest emitter of greenhouse gases, contributing to 12% of the country’s equivalent Carbon dioxide emissions. These emissions have various negative impacts on the planet, which impede the transition towards a cleaner environment and more sustainable communities. Attention has now shifted towards Carbon dioxide reduction in addition to the currently practiced energy efficiency improvements and source switching, which is also important in achieving Canada’s 2030 climate action goals. The current study attempts to address the above gap by investigating the feasibility of installing carbon capturing unit at building level, based on the perceptions of building managers in both multi-unit residential buildings and non-residential buildings. A Modified Digital Logic approach was used to identify the key factors that determine the acceptability of the unit, based on experts’ input. Six primary criteria were identified to design a questionnaire and structured interviews to evaluate the acceptability of building level carbon capturing unit to stakeholders. The findings indicated that around 50% of non-residential building managers were interested in installing the carbon capturing unit, whereas none of the multi-unit building managers were in favor of the unit installation. The lack of interest is attributed to different factors such as unit scalability, inability to accurately estimate the short and long-term economic benefits, and other alternate plans to reduce carbon dioxide emissions. Specifically, when establishing relationship between cost and unit scalability, 82% of residential unit managers and 50% of non-residential managers opined that the unit should be capable of being upgraded to accommodate a larger area and capture more emissions in order to justify the proposed cost of the unit. The findings provide important insights for policy makers in understanding the acceptability of carbon capturing unit at building level and to further develop and promote this emerging technology in the market.

Provincial cattle carbon emissions from enteric fermentation and manure management in South Africa

Livestock is a major producer of agricultural greenhouse gas emissions in South Africa. Cattle methane (CH4) from enteric fermentation is the main source of the emissions. However, due to shortage of information to guide agricultural mitigation plans in the country, the main objective of this study is to investigate causal factors of the emissions from cattle in all nine national provinces. This study calculates provincial CH4 emission factors and factors (i.e. nitrogen excretion rate and average annual nitrogen excretion per animal) required for nitrous oxide (N2O) emissions from cattle manure management. The study further uses these factors and other values obtained from the literature to calculate cattle CH4 emissions from enteric fermentation and manure management. It also provides similar N2O emissions from manure management as well as urine and dung deposited on the pasture, range and paddock. The emissions are calculated for each cattle type: commercial dairy, commercial beef, subsistence and feedlot cattle. Cattle in South Africa produced a total of 35.37 million tonnes (Mt) of carbon dioxide equivalent (CO2e) emissions in 2019, inclusive of emissions from pasture, range and paddock. Methane from enteric fermentation accounts for 64.54% of the total emissions followed by emissions from pasture, range and paddock (27.66%). Manure management contributes 4.34% of N2O to the total emissions while this source also produces 3.45% of CH4 emissions. Commercial beef is responsible for 50.21% of the total emissions, followed by subsistence beef (36.72%), commercial dairy (10.52%) and feedlot cattle (2.52%). The Eastern Cape province is the highest producer of cattle emissions with 8.66 Mt CO2e, a quarter of the emissions. It is followed by KwaZulu-Natal (7.14 Mt CO2e, 20%) and the Free State (5.65 Mt CO2e, 16%). Gauteng province is responsible for the lowest producer of the emissions with 0.71 Mt CO2e (2%) of the total. South Africa's emission factors are higher than values for Africa, indicating importance of developing national factors to avoid uncertainties in emissions. As a result of national landscape and environmental conditions, the eastern provinces of the country are major sources of cattle emissions in the country.

Equivalent Carbon Dioxide Emission in Useful Energy Generation in the Heat-generating Plant – Application of the Carbon Footprint Methodology

Equivalent Carbon Dioxide Emission in Useful Energy Generation in the Heat-generating Plant – Application of the Carbon Footprint Methodology

Estimation of the Carbon Footprint Associated With Attendees of the American Psychiatric Association Annual Meeting

This cross-sectional study uses data from the 2018 and 2019 American Psychiatric Association (APA) annual meetings to assess the carbon dioxide equivalent emissions associated with the conferences and how they may be reduced.

Analytical study of carbon dioxide equivalent emission from agricultural drain surfaces — a case study from Egypt*

AbstractMethane emission is usually converted into equivalent carbon dioxide (CO2e) in order to compare it with other sectoral emissions. Estimation of methane from ‘agricultural drain surfaces’ is not accounted for in most of the derivation methods. This research paper dealt with the estimation of CO2e emission from ‘surfaces of the agricultural drains network in Egypt’ and then estimated the projected future CO2e emission loads trend for the period 2046–2065. CO2e emission was estimated using general circulation models for climate change under expected temperature variation in the coming decades. Annual average total CO2e emission loads from the BHD surface and its surrounding areas to the atmosphere were about 3790 t eq. CO2e yr‾¹ for the period 2046–2065. The ‘additional’ total emission of CO2e from the agriculture drainage network surface in relation to total emissions from the agricultural sector in Egypt was about 13.8%. It also accounted for about 1.4% of overall CO2e emission in Egypt. This research paper, furthermore, developed a methane indicative emission map for the Egyptian agricultural drainage network for the period 2046–2065, through which it is possible to estimate CO2e emission loads at any segment on any agricultural drain in Egypt during the period 2046–2065.

Determinants of CO2 emissions generated by air travel vary across reasons for the trip

This study estimates factors of importance for the carbon dioxide equivalent (CO2e) emissions generated by travellers flying for different reasons based on representative Austrian micro data for the period 2014–2016. The annual average number of flights taken by adults vary between 0.1 (visiting friends) and 0.8 (going on holiday), and the amount of CO2e emissions generated by each return flight is approximately 1100 kg. This leads to a total of 6 million tonnes CO2e emissions per year. Results of the Pseudo Poisson Maximum Likelihood estimations reveal that the amount of CO2e emissions created is related to socio-demographic, locational and seasonal factors, although mainly for the largest group of travellers: the holiday makers. In this group, individuals with university degrees, young persons (16–24 years) and capital city residents generate the largest amounts of emissions, as opposed to persons with children and large households. Residents of the capital region each quarter cause 64 kg more CO2e emissions than inhabitants of rural areas, persons with university degrees create 74 kg larger emissions than those without degrees and young adults instigate 90 kg more emissions than middle-aged persons. CO2e emissions of holiday flights are highest in the first quarter of the year. The importance of education is also pronounced for CO2e emissions related to business travel, as is gender.

Outlook of future implementation of PEMFC and SOFC onboard cruise ships

According to third IMO GHG Study shipping is responsible of about 2, 6% of world CO2e (carbon dioxide equivalent) emissions. The dangerous effect on people is increased because emissions are concentrated in coastal areas. IMO and other bodies are engaged in imposing measures to reduce GHG emissions and improve the overall ship’s energy efficiency. There are many technical and operational improvements that can help to reach these goals, but hydrogen and fuel cells remain one of the best candidates to substantially reduce emissions and fuel consumption. This paper gives an outlook of possible fuel cells applications in the marine sector and analyses the potential of Proton Exchange Membrane Fuel Cells (PEMFC) and Solid Oxide Fuel Cells (SOFC) for the on-board installation. The analysis shows the advantages that fuel cells can give in terms of emissions reductions and fuel saving, but also highlights some challenges that designers will face when implementing these technologies on a cruise ship. Both PEMFC and SOFC application in the marine sector suffer of the lack of standards and regulations from IMO and Classification Societies and high acquisition cost. While PEMFC are ready for marine application, SOFC are still in a study phase for on-board implementation. Also, the type of fuel used by these generators and the possibility of heat recovery can influence their application on-board cruise ships.

Stochastic Optimization for Security-Constrained Day-Ahead Operational Planning Under PV Production Uncertainties: Reduction Analysis of Operating Economic Costs and Carbon Emissions

This paper presents a general operational planning framework for controllable generators, one day ahead, under uncertain re-newable energy generation. The effect of photovoltaic (PV) power generation uncertainty on operating decisions is examined by incorporating expected possible uncertainties into a two-stage unit commitment optimization. The planning objective consists in minimizing operating costs and/or equivalent carbon dioxide (CO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> ) emissions. Based on distributions of forecasting errors of the net demand, a LOLP-based risk assessment method is proposed to determine an appropriate amount of operating reserve (OR) for each time step of the next day. Then, in a first stage, a deterministic optimization within a mixed-integer linear programming (MILP) method generates the unit commitment of controllable generators with the day-ahead PV and load demand prediction and the prescribed OR requirement. In a second stage, possible future forecasting uncertainties are considered. Hence, a stochastic operational planning is optimized in order to commit enough flexible generators to handle unexpected deviations from predic-tions. The proposed methodology is implemented for a local energy community. Results regarding the available operating reserve, operating costs and CO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> emissions are established and compared. About 15% of economic operating costs and environmental costs are saved, compared to a deterministic generation planning while ensuring the targeted security level.

Toward a Tradable, Low-Carbon Product Standard for Steel: Policy Design Considerations for the United States

Steel production in the United States accounts for around 100 million tons of carbon dioxide equivalent emissions. Available and emerging technologies have the ability to significantly decarbonize the steel industry. A low-carbon product standard for steel in the United States can incentivize the adoption of these technologies and result in emissions reductions while preserving the international competitiveness of domestic steel manufacturers.

Can the 1.5 ℃ warming target be met in a global transition to 100% renewable energy?

&lt;abstract&gt; &lt;p&gt;First, we recognize the valuable previous studies which model renewable energy growth with complete termination of fossil fuels along with assumptions of the remaining carbon budgets to reach IPCC warming targets. However, these studies use very complex combined economic/physical modeling and commonly lack transparency regarding the sensitivity to assumed inputs. Moreover, it is not clear that energy poverty with its big present impact in the global South has been eliminated in their scenarios. Further, their CO&lt;sub&gt;2&lt;/sub&gt;-equivalent natural gas emission factors are underestimated, which will have significant impact on the computed greenhouse gas emissions. Therefore, we address this question in a transparent modeling study: can the 1.5 ℃ warming target still be met with an aggressive phaseout of fossil fuels coupled with a 100% replacement by renewable energy? We compute the continuous generation of global wind/solar energy power along with the cumulative carbon dioxide equivalent emissions in a complete phaseout of fossil fuels over a 20 year period. We compare these computed emissions with the state-of-the-science estimates for the remaining carbon budget of carbon dioxide emissions consistent with the 1.5 ℃ warming target, concluding that it is still possible to meet this warming target if the creation of a global 100% renewable energy transition of sufficient capacity begins very soon which will likely be needed to power aggressive negative carbon emission technology. The latter is focused on direct air capture for crustal storage. More efficient renewable technologies in the near future will make this transition easier and promote the implementation of a global circular economy. Taking into account technological improvements in 2&lt;sup&gt;nd&lt;/sup&gt; law (exergy) efficiencies reducing the necessary global energy demand, the renewable supply should likely be no more than 1.5 times the present level, with the capacity to eliminate global energy poverty, for climate mitigation and adaptation.&lt;/p&gt; &lt;/abstract&gt;