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With pressure on designers to provide sustainability driven structural solutions, making best use of resources in structural design becomes paramount. In particular, cement is one of the greatest CO2 contributors and its use in concrete structures means that optimisation to minimise material and weight is crucial. Optimal design techniques, such as the bone growth analogy, result in extraordinary images of curvaceous and interesting optimised systems. However, the link to practical construction has not always been considered. Simultaneous with this sort of optimisation, various researchers around the world have been looking at the use of flexible fabric formwork for the casting of interesting architectural concrete structures. This previous research has not fully made the link between beauty and precise prediction of final geometry. This paper describes recent research at the University of Bath, which has created a link between aesthetic appeal, structural optimisation, precise definition of final geometric form, and practicality of construction. The paper describes how optimally designed flexibly-formed concrete structural elements may be designed and constructed. It is shown that accurate prediction of final bulbous shapes is possible, that control of structural capacity at any section of the element is feasible, and that highly-aesthetic outcomes are achievable. [ABSTRACT FROM AUTHOR]

By not following standard scientific nomenclature for parts per million by volume (ppmv) and parts per million by mass (ppm), the authors of Climate Change 2007: The Physical Science Basis (AR4), introduced confusion between these units. This confusion in AR4 has spread to the scientific community and has potential to create problems. Carbon dioxide contributed approximately 11% of the change in atmospheric warming during the period from the ice ages to the pre-industrial level of 275 ppmv. This is consistent with the current proportion of warming by carbon dioxide, and casts doubt on carbon dioxide being almost 100% of the cause of atmospheric warming from 275 to 378 ppmv. The climate sensitivity parameter calculated for the projected temperature change range of 2.9°C to 6.4°C is physically impossible to achieve. The lower temperature range is unreliable. The Intergovernmental Panel on Climate Change has an important obligation to make these problems known to policymakers and the public. [ABSTRACT FROM AUTHOR]

The roles digital media-technologies play in raising public issues relating to emerging technologies and their potential for engaging publics with science and policy assessments is a lively field of inquiry in Science and Technology Studies (STS). This paper presents an analysis of controversies over proposals for the large-scale removal of atmospheric carbon dioxide (CDR). The study combines a digital method (web-querying) with document analysis to map debates about two CDR approaches: bioenergy with carbon capture and storage (BECCS) and afforestation. In the first step, we locate actors using the web to engage with BECCS and afforestation and map their alignments in relation to competing framings of CDR. In a second step, we examine the devices deployed by UK-based actors to evidence and contest the feasibility of BECCS and afforestation. Our analysis shows that policy distinctions between "natural" and "engineered" CDR are used flexibly in practice and do not map neatly onto actor engagement with BECCS and afforestation. We highlight the predominance of cross-cutting techno-economic expertise and argue that framings of CDR as a solution to governing climate change may contribute to public disengagement from climate policy processes. The paper reflects on methods for studying controversies, publics, and issues emerging around processes of technoscientific assessment. [ABSTRACT FROM AUTHOR]

The Intergovernmental Panel on Climate Change defines lifetime for CO2 as the time required for the atmosphere to adjust to a future equilibrium state, and it gives a wide range of 5-200 years; however, a number of published data show a short lifetime of 5-15 years. This implies that anthropogenic emissions of CO2 are sequestrated more easily than expected, suggesting it would be beneficial to look at other climate factors when making long-term predictions. Considering the magnitude and the time length (cycle), climate change can be interpreted as the result of the complex coupling of astronomic forces (e.g. the Earth's orbit and cosmic-ray flux) as well as terrestrial forces. Regarding the Earth's climate as a complex (nonlinear) system, it is necessary for the climate research community and policy makers to distinguish between variations caused by anthropogenic and natural occurrences, and the problem of how to do so arises. [ABSTRACT FROM AUTHOR]

Over the past century, the concentration of carbon dioxide (CO2) has significantly increased in our atmosphere, creating numerous catastrophic effects and environmental impacts. There are three main CO2 capture methods: (a) post-combustion, (b) pre-combustion, and (c) oxy-fuel combustion implemented to capture CO2 from significant CO2 emitting sources. Further, the captured CO2 is utilized to convert it into value-added products. The current status of potential combined CO2 capture and CO2 utilization methods provide the solution to the issues of greenhouse-gas CO2 emissions from anthropogenic activities and the ever-growing energy demand challenges. These unique approaches dramatically reduce the overall energy penalty, cost-effective, and have a low environmental impact. As of now, carbon management is more intensively shifting toward the carbon utilization for minimizing energy consumption and replacing fossil fuel with the cleaner energy sources. This paper presents an idea of co-integration pathways for CO2 capture and CO2 utilization. [ABSTRACT FROM AUTHOR]

Background: Respiratory depression is the most feared opioid-related side-effect yet research on the topic is sparse. We evaluated changes in respiratory parameters during parenteral opioid titration for cancer pain to determine if opioid titration was associated with evidence of hypoventilation. The primary outcome measure was to measure changes in end-tidal CO2 (ET-CO2) during opioid titration to pain control. Methods: Subjects with severe cancer pain admitted for parenteral opioid titration for poorly controlled pain were eligible. Those who were oxygen dependent were excluded. ET-CO2, O2 saturation, respiratory rate (RR), and vital signs were monitored daily until pain control was achieved. Results: 30 patients completed the study of which 29 are reported. The mean ET-CO2 at initial evaluation was 33.39±5.0 and 34.79±5.7 mmHg at pain control (P=0.14, 95% CI -0.5 to 3.3). None had an ET-CO2 ⩾50 mmHg. All maintained O2 saturation ⩾92%. RR dropped transiently below 10/minute in two subjects. Conclusions: Parenteral opioid titration for relief of cancer pain was not associated with respiratory depression as demonstrated by significant changes in ET-CO2 or oxygen saturation in non-oxygen dependent cancer patients. [ABSTRACT FROM AUTHOR]

Carbon dioxide is the largest component of the human footprint and one of the major components of all greenhouse gases. The expected increase in population will lead to growth in energy consumption and greenhouse gas emissions. The building industry has the highest potential for reducing greenhouse gas emissions. Therefore, buildings should become not only efficient consumers but also energy producers, not a simple task in dense cities. The paper describes the feasibility and limitations of near zero energy design in highly dense urban conditions. The study was carried out by examination and comparison of various density design, alternatives of an existing urban plot in the coastal climate zone of Israel. Increased dwelling units' number leads to higher total energy use on the one hand and mutual shading of new high-rise residential buildings on the other. Preserving solar rights for PV systems installation become more complex. The relation between urban density and solar rights in urban design, energy consumption and energy generation within plot borders and their implications are presented and discussed in the paper. [ABSTRACT FROM AUTHOR]

The article describes a study which compared the financial and environmental costs of reusable and single-use/disposable plastic anaesthetic drug trays using a life cycle assessment (LCA) model. LCA modeling revealed that single-use plastic trays are more expensive, produced more carbon dioxide, and consumed more water as compared to the reusable trays.

Climate change has been considerable concerned because of the increasing greenhouse gas (GHG) emissions. Gansu province is a typical less-developed and heavy chemical industrial province, its CO2 emission per unit of the gross domestic product (GDP) is 252.52 ton per million Chinese yuan (t/M-CNY) in 2019, which is 48.42% more than national average value. Gansu province faces the following dual pressures including maintaining economic growth and reducing carbon dioxide (CO2) emissions. This paper establishes a low carbon development system dynamics model in order to investigate the effects of four carbon reduction measures (technical progress, industrial transformation, fuel substitution, and low carbon awareness) on reducing CO2 emission over the period of 2020–2030. The simulation results indicate that, without direct intervention, the CO2 emissions per unit of GDP is projected to be 171.34 t/M-CNY by 2030. While utilizing technical progress, implementing industrial transformation, fuel substitution, and low carbon awareness could potentially be 2.12%, 3.33%, 0.72% and 1.27%, respectively less than that. For the sake of achieving the goal of CO2 reduction in the long run, the local government should address today's industrial transformation and adopt reasonable combination of adjustment and control policies immediately. [ABSTRACT FROM AUTHOR]

Using historical data from Nepal - one of the largest recipients of aid among South Asian countries - this paper investigates the link between foreign aid, growth, remittances and carbon dioxide (CO2) emissions. The investigation of this issue is particularly important, as policy makers in the least developed countries are increasingly concerned about growing reliance on energy imports, particularly fossil fuels, and increasing CO2 emissions. Mounting energy consumption has not only made their economies vulnerable to environmental disasters and increased health costs, but also to external shocks due to frequent fluctuations in international market prices for petroleum products. Since available studies are largely based on cross-sectional data - which lump together countries with different characteristics - empirical evidence is contradictory. In-depth case studies of countries with different backgrounds would certainly provide better insights into the link between aid, growth, remittances and CO2 emissions, and contribute to ongoing policy dialogue. Our empirical results, based on an in-depth case study of Nepal, suggest that more foreign aid and remittances reduce CO2 emissions, whereas financial development and higher income increase CO2 emissions. These findings point to the importance of market mechanisms for regulating financial development and higher income to control CO2 emissions, without undermining competitiveness. [ABSTRACT FROM AUTHOR]

The aim of this paper is to showcase different decarbonization pathways for Europe with varying Carbon dioxide (CO2) constraints until 2050. The Global Energy System Model (GENeSYS-MOD) framework, a linear mathematical optimization model, is used to compute low-carbon scenarios for 17 European countries or regions. The sectors power, lowand high-temperature heating, and passenger and freight transportation are included, with the model endogenously constructing capacities in each period. Emission constraints differ between different scenarios and are either optimized endogenously by the model, or distributed on a per-capita basis, GDP-dependent, or based on current emissions. The results show a rapid phase-in of renewable energies, if a carbon budget in line with established international climate targets is chosen. It can be shown that the achievement of the 2° target can be met with low additional costs compared to the business as usual case, while reducing total emissions by more than 30%. [ABSTRACT FROM AUTHOR]

Corrosion-resistant alloys (CRAs) are employed in severe oil and gas production environments that operate at high pressures and temperatures and contain chlorides, CO2, and H2S. They exhibit high resistance to uniform corrosion in these environments due to their passivity. However, they can suffer from different forms of environmentally assisted cracking (EAC), depending on the environmental and metallurgical conditions. This paper reviews the recent literature of EAC in CRAs and presents an overall framework for evaluating the SCC based on electrochemical modelling of corrosion and repassivation potentials for localised corrosion. The modelling is supported by experimental data on crack growth as a function of environmental variables, alloy content, and potential. This paper is part of a supplementary issue from the 17th Asia-Pacific Corrosion Control Conference (APCCC-17). [ABSTRACT FROM AUTHOR]

Carbon dioxide (CO2) flooding is an effective method to enhance oil recovery in low-permeability reservoirs. Studying key geological factors controlling oil displacement efficiency is of great significance to the CO2 injection scheme design in low-permeability reservoirs. Focusing on low-permeable H reservoir in Songliao Basin, China, this paper describes the contact and connection of sand bodies, natural fractures and high-permeability zones with core samples, log data and experiment firstly. After that, the impact of interaction of sand body connection, natural fracture and high-permeability zone on oil displacement efficiency is determined by using geological and dynamic data in CO2 injection area. Results indicate that the connection of single sand bodies between injectors and producters wells primarily controls CO2 flooding in low-permeability reservoirs. Furthermore, coupling of sand body connection, natural fractures and high-permeability zones is the key geological factor governing oil displacement efficiency of CO2 injection in low-permeability reservoirs, where well or generally-connected sand bodies can improve the efficiency significantly. Meanwhile, the dominant seepage channels in other directions have no influence on producers, which is beneficial to improve CO2 flooding efficiency. [ABSTRACT FROM AUTHOR]

This paper measures the technical inefficiency and the shadow price of Korean fossil-fuel generation companies (GENCOs) between 2001 and 2016 at the firm-level. To obtain robust empirical results, this study employs both commonly used deterministic and stochastic estimation methods. The empirical results are as follows: the inefficiency estimates are approximately 0.09 (deterministic) and 0.08 (stochastic); the estimates of CO2 shadow price, in KRW/tCO2, are 82,758 (deterministic) and 49,830 (stochastic), which shows high volatility in the annual average shadow price. In addition, we find that the results of the deterministic method without any random errors show a large variation in the trends of technical inefficiency and shadow price, while the stochastic method with random errors yields only moderate volatility. Our empirical results are expected to assist policymakers in determining how much potential mitigation can be achieved through improved efficiency, and the range of the CO2 shadow price will contribute to more efficient policy tools. [ABSTRACT FROM AUTHOR]

Columns manufactured with pre-cast concrete could reduce construction waste and CO2 emissions by reducing the use of temporary materials such as formwork. In this paper, three types of connection methods are introduced. The structural performance of pre-cast composite columns connected to beams was investigated for the column connection. Multi-story pre-cast composite columns could significantly reduce the construction time, resulting in a decrease in CO2 emissions. This paper reports the analysis of the compression and bending of a two-story column so as to verify the structural performances of pre-cast composite columns to provide adequate integrity to ensure a safe environment for building accommodation. In addition, a steel-framed column and a steel-framed reinforced concrete (SRC) column configured to feature the same compression performance as a pre-cast composite column were designed on the basis of the analysis results. The CO2 emissions and energy efficiency of the composite columns were compared with those of conventional steel and SRC columns during the design and construction phases. This paper also presents new composite columns providing efficient energy consumption with reduced CO2 emissions for a more environmentally conscientious construction of buildings. [ABSTRACT FROM AUTHOR]

The present paper aims to reliably depict the impact of the European Union Emissions Trading Scheme (EU ETS) on Spain under different assumptions about the industries involved. Prior analyses, based either on highly aggregated macroeconomic or specific electricity industry models, have been limited in degree of detail or scope. Two types of modeling were combined in the present study: general equilibrium was used to assess the impact on different industries and to explain cross-industry changes, and partial equilibrium to suitably model the complex and crucial electricity system. Combining and interrelating these two models yields the effects on price, carbon dioxide (CO2) emissions and distributional patterns in Spain of both the current policy and of an alternative in which all industries take part in the EU ETS. Since Spain is a key participant in this scheme, the conclusions and policy implications stemming from this paper are relevant to and useful for post-Kyoto arrangements. [ABSTRACT FROM AUTHOR]

Climate policy measures aimed at power markets influence the cost structure of producers and price patterns, and are therefore likely to influence the production decision of power plants, even in the short run. When power plants have costs related to starting and stopping, decisions on short-term production are intertemporal, and the conventional 'price vs. marginal cost' rule is not sufficient to predict production in thermal power plants. This paper analyzes how the optimal production decision is influenced by climate policies: namely, CO2 trading mechanisms, the expansion of renewables and the interaction between these policies. The main result is that higher power price variation (as a result of increased wind power production) makes the thermal power producer less flexible, but the effect on emissions is ambiguous. A CO2 cost (as a result of an emission trading system) increases the flexibility of the producer and the operation decision resembles the conventional 'price vs. marginal cost' rule more. This implies lower emissions. However, when the CO2 price is coupled with higher power price variation, the positive effects may be reversed since the two policies have opposing effects. [ABSTRACT FROM AUTHOR]

The current paper presents a new process for postcombustion carbon capture. An historical survey of the cryogenic techniques used in the chemical industry for the removal of acid vapours is given, with particular emphasis on two Ryan–Holmes-based processes. The paper suggests that these two processes have the potential to achieve CO2 separation from flue gas with high second law efficiency. A further variation on these processes is then proposed enabling the simultaneous capture of CO2, SO2, and NO The paper starts with a discussion of the most suitable absorbent for the process; liquid SO2 is suggested and a simplified analysis of an absorption column is conducted using the technique developed by Souders and Brown. This analysis shows that with only four theoretical stages and an acceptable liquid/gas ratio of two, SO2 is able to absorb CO2 and leave a residual concentration of CO2 in the flue gas equivalent to 90 per cent carbon capture. The final section of the paper describes the use of dilute H2SO4 as a precooling stream to reduce the temperature of the flue gas prior to it entering the CO2 scrubbing section. It is proposed to produce the necessary H2SO4 from the constituents of the flue gas using similar reactions to those of the ‘lead-chamber process’. The H2SO4 stream is also used to reheat the flue gas before it is passed to the chimney. It is shown that an important attribute of the H2SO4 stream is its role as a ‘lean-oil’, reducing SO2 emissions from the power station to well below the levels required by future legislation. [ABSTRACT FROM AUTHOR]

This paper summarizes results from ten global economy-energy-environment models implementing mechanisms of endogenous technological change (ETC). Climate policy goals represented as different CO2 stabilization levels are imposed, and the contribution of induced technological change (ITC) to meeting the goals is assessed. Findings indicate that climate policy induces additional technological change, in some models substantially. Its effect is a reduction of abatement costs in all participating models. The majority of models calculate abatement costs below 1 percent of present value aggregate gross world product for the period 2000-2100. The models predict different dynamics for rising carbon costs, with some showing a decline in carbon costs towards the end of the century. There are a number of reasons for differences in results between models; however four major drivers of differences are identified. First, the extent of the necessary CO2 reduction which depends mainly on predicted baseline emissions, determines how much a model is challenged to comply with climate policy. Second, when climate policy can offset market distortions, some models show that not costs but benefits accrue from climate policy. Third, assumptions about long-term investment behavior, e.g. foresight of actors and number of available investment options, exert a major influence. Finally whether and how options for carbon-free energy are implemented (backstop and end-of-the-pipe technologies) strongly affects both the mitigation strategy and the abatement costs. [ABSTRACT FROM AUTHOR]

Carbon dioxide emissions abatement in a group of countries can result in increased emissions in non-abating countries. This effect has been referred to as carbon leakage. The Kyoto Protocol calls for a number of industrialized countries to limit their emissions while other countries have no abatement commitments. This paper assesses the sectoral and regional determinants of the leakage in a static multi-sector, multi-regional computable general equilibrium model. In baseline estimates based on our model, the Kyoto Protocol leads to a carbon leakage rate of 10 percent. A decomposition technique is applied which attributes increases in CO[sub 2] emissions by non-participating countries to specific sectors in the abating countries. This information is important for the debate on the tax exemptions for certain industries in the participating countries as it provides information for the most- and least-leakage contributing sectors of the economy. Additional calculations indicate the need for caution in the carbon tax design. Exemptions of any sector from a carbon tax are not justified because they lower welfare in a region. The degree of sectoral and regional data disaggregation, and international capital mobility do not change the leakage rate significantly. Fossil-fuel supply elasticities and trade substitution elasticities are crucial determinants for projecting the total Worm emissions of CO[sub 2]. [ABSTRACT FROM AUTHOR]

This paper challenges the view that improving the efficiency of energy use will lead to a reduction in national energy consumption, and hence is an effective policy for reducing CO2 emissions. It argues that improving energy efficiency lowers the implicit price of energy and hence make its use more affordable, thus leading to greater use. The paper presents the views of economists, as well as green critics of 'efficiency' and the 'dematerialization' thesis. The paper argues that a more effective CO2 policy is to concentrate on shifting to non-fossil fuel fuels, like renewables, subsidized through a carbon tax. Ultimately what is needed, to limit energy consumption, is energy conservation not energy efficiency. [ABSTRACT FROM AUTHOR]

The present study investigates the effect of public–private partnership investment in energy and renewable energy consumption on carbon dioxide (CO2) emissions, taking into account the critical role of economic growth and trade openness in Pakistan from 1992 to 2019. The linear and nonlinear autoregressive distributed lag models are employed to check the co-integration link between dependent and independent variables, further estimate short-run and long-run associations, and examine the symmetric and asymmetric effects of public–private partnership investment in energy on CO2 emissions in Pakistan. The empirical findings show that public–private partnership investment in energy reduces environmental quality by increasing CO2 emissions. Similarly, economic development and trade openness harms the atmosphere by raising CO2 emissions. On the other hand, renewable energy consumption significantly negatively affects CO2 emissions. In addition, the findings also authenticate the asymmetric link between public–private partnership investment in energy and the environment, as CO2 emissions are caused mainly by positive shocks in public–private partnership investment in energy in the short and long run. This study proposes financing renewable energy projects through public–private partnership is needed for an environmentally friendly future. [ABSTRACT FROM AUTHOR]

This paper estimates consumer savings, CO2 emissions reductions, and price effects from increasing demand response (DR) dispatch in the Midcontinent Independent System Operator (MISO) electricity market. To quantify market effects, we develop a dynamic supply and demand model to explore a range of DR deployment scenarios. The study is motivated by the existence of regulatory and market rule barriers to market-based deployment of DR resources in the MISO region. We show annual consumer savings from increased market-based DR can vary from $1.3 million to $17.6 million under typical peak operating conditions, depending on the amount of DR resources available for market dispatch and the frequency of deployment. Consumer savings and other market effects increase exponentially during atypical periods with tight supply and high prices. Additionally, we find that DR deployment often reduces CO2 emissions, but the magnitude of emissions reductions varies depending on the emissions content of marginal generation at the time and location of deployment. The results of this study suggest regulators and other stakeholders should focus policy efforts to reducing regulatory barriers to DR deployment in wholesale markets, particularly in locations that experience high price spikes, to improve market efficiency and achieve cost savings for consumers. [ABSTRACT FROM AUTHOR]

The photovoltaic thermal greenhouse system highly supports the production of biogas. The system’s prime advantage is biogas heating and crop drying through varied directions of air flow. Further, it diminishes the upward loss of the system. This paper aims to model a practical greenhouse system for obtaining the precise estimation of the heating efficiency, given by the solar radiance. The simulation model adopts the self-adaptive firefly neural network model that applies on known experimental data. Therefore, the error function between the model outcome and the experimental outcome is substantially minimized. The performance analysis involves an effective comparative study on the root mean square error between the adopted self-adaptive firefly neural network model and the conventional models such as Levenberg–Marquardt neural network and firefly neural network. Later, the impact of self-adaptiveness, FF update and learning performance on attaining the knowledge regarding the characteristics of SAFF algorithm is analysed to yield better performance. [ABSTRACT FROM AUTHOR]

The U.S. Clean Power Plan stipulates a state-specific performance-based CO2 emission standard, delegating states with considerable flexibility for using either a tradable performance-based or a mass-based permit program. This paper analyzes these two standards under imperfect competitive. We limit our attention to (1) short-run analyses and (2) a situation in which all states are subject to the same type of standard. We show that while the cross-subsidy inherent in the performance- based standard might effectively reduce power prices, it could also inflate energy consumption. A dominant firm with a relatively clean endowment under the performance-based standard would be able to manipulate the electricity market as well as to elevate permit prices, which might worsen market outcomes compared to its mass-based counterpart. On the other hand, the "cross-subsidy" could be the dominant force leading to a higher social welfare if the leader has a relatively dirty endowment. [ABSTRACT FROM AUTHOR]

Concrete, one of the construction materials used for apartment buildings, emits some toxic substances including CO2 and chromium VI that are detrimental to occupants. This paper presents pre-cast composite beams with T-type steels at each end to reduce the use of concrete. The new structural system is developed to replace the bearing walls of conventional apartment buildings. The pre-cast composite beams of the new concept (which can be used for apartment buildings) provide similar floor depth while minimizing the use of concrete materials. The CO2 and chromium VI emissions estimated from apartment buildings constructed with bearing walls are compared with those from buildings designed with the proposed composite beams. The data obtained from the previous study of Hong et al. [Hong WK, Kim JM, Park SC, Lee SG, Kim SI, Yoon KJ, Kim HC, Kim JT: A new apartment construction technology with effective CO2 emission reduction capabilities: Energy Int J 2010;35(6):2639–2646; Hong WK, Park SC, Kim JM, Kim SI, Lee SG, Yune DY, Yoon TH, Ryoo BY: Development of structural composite hybrid systems and their application with regard to the reduction of CO2 emissions: Indoor Built Environ 2010;19(1):151–162] for the amount of concrete material in the apartment buildings was used to estimate the amounts of CO2 and chromium VI emissions. The pre-cast composite beams of the new concept are believed to be an effective structural system to reduce the use of concrete material, which in turn reduces the amounts of the noxious materials, CO2 and chromium VI. The new healthy structural frame system introduced in this paper shows the potential to enhance the health of occupants. [ABSTRACT FROM AUTHOR]