In the last decade, we have experienced a changing geopolitical context that has caused changes in the energy context. In addition, human activity contributes to global warming or sea level rising, i.e., climate change. A set of action policies have been implemented to continue fighting against this environmental situation (such as the Paris Agreement, the COP27, or the European Green Deal for 2030); therefore, it is necessary to determine whether we are on the right track. It is compulsory to develop predictive models that accurately analyze the current status and the already path undertaken. To this end, this article analyzes the environmental efficiency of the 27 countries of the European Union (excluding the UK) using the so-called data envelopment analysis (DEA). In particular, economic (GDP and GDP per capita), environmental (CO2 and CH4 emissions), electricity production data, the volume of vehicles, and the industrial production rate of the different countries were collected to calculate environmental efficiency. Once these data were collected, the environmental efficiency was calculated using two methods based on the DEA. The results show that out of the 27 countries, only 12 have a relatively high environmental efficiency, although it could be improved, implementing a set of corrections. However, other countries have a low eco-efficiency performance and they must improve in the coming years. We can highlight that rich countries are closer to achieving high environmental efficiency than less developed countries.

Water footprint (WF) is an appropriate tool to help any water-intensive industrial system to adapt to climate change. WF is a metric where the direct and indirect freshwater consumption of a country, firm, activity, or product are quantified. Most of existing WF literature emphasizes the assessment of products, not the optimal decision making in the supply chain. To address this research gap, a bi-objective optimization model is developed for supplier selection in a supply chain that minimizes costs and WF. Apart from determining the sources of raw materials to use in producing the products, the model also determines the actions to be taken by the firm in case of supply shortages. The model is demonstrated using three illustrative case studies which show that WF embedded in the raw materials can influence the actions to be taken when addressing issues on raw material availability. The WF becomes significant in the decisions in this bi-objective optimization problem when it is given a weight of at least 20% (or the weight of the cost is at most 80%) for case study 1 and at least 50% for case study 2. When the assigned weight in cost reaches the point where WF becomes significant, the increase in the assigned weight in WF has an inverse impact on the total cost. Case study 3 demonstrates the stochastic variant of the model.

The crucial role of sustainable development and resiliency strategies is undeniable in today's competitive market space, especially after the Coronavirus outbreak. Hence, this research develops a multistage decision-making framework to investigate the supply chain network design problem considering the sustainability and resiliency dimensions. In this way, the scores of the potential suppliers based on the sustainability and resilience dimensions were calculated using the MADM methods, and then, these scores were applied as inputs in the proposed mathematical model (the second stage), which determined which supplier should be selected. The proposed model aims to minimize the total costs, maximize the suppliers' sustainability and resiliency, and maximize the distribution centers' resiliency. Then, the proposed model is solved by the preemptive fuzzy goal programming method. Overall, the main objectives and aims of the current work are to present a comprehensive decision-making model that can incorporate the sustainability and resilience dimensions into the supplier selection and supply chain configuration processes. In general, the main contributions and advantages of this work can be summarized as follows: (i) this research simultaneously investigates the sustainability and resiliency concepts in the dairy supply chain, (ii) the current work develops an efficient multistage decision-making model that can evaluate the suppliers based on the resilience and sustainability dimensions and configure the supply chain network, simultaneously. Based on the obtained results, the responsiveness and facilities reinforcement indicators are the most important indicators for the resilient aspect. On the other hand, reliability and quality are the most important indicators of sustainability aspect. Also, the results show that a large percentage of supply chain costs are related to purchasing and production costs. Besides, according to the outputs, the total cost of supply chain increases by enhancing the demand.

Mine water can be a renewable and economical source of geothermal and hydraulic energy. Nine discharges from closed and flooded coal mines in the Laciana Valley (León, NW Spain) have been studied. Various technologies for the energy use of mine water, as well as the influence of factors such as temperature, the need for water treatment, investment, potential customers and expansion capacity, have been evaluated by means of a decision-making tool. It is concluded that the most advantageous option is an open-loop geothermal system using the waters of a mountain mine, the temperature of which exceeds 14 °C and whose distance to customers is less than 2 km. A technical-economic viability study for a district heating network designed to supply heating and hot water to six public buildings in the nearby town of Villablino is presented. The proposed use of mine water might help areas that have been greatly affected socioeconomically by the closure of the mines and has other advantages compared to conventional energy systems, such as the reduction of CO emissions.

Objective is to analyze the economic feasibility of implementing a greenhouse in a hydroponics production system in substrate (sand) on a small family farm as an alternative to hydroponic cultivation using nutrient film technique (NFT). This case study was carried out in the Municipality of Dourados, Mato Grosso do Sul state, Brazil. The location was specifically selected because of the importance of agricultural activities and the need for productive diversification related to the context of the small rural producer. As a criterion for assessing economic viability, the techniques of net present value (NPV), internal rate of return (IRR), modified internal rate of return (MIRR), cost-benefit (C/B), profitability index (PI), equivalent annual value (EAV) and discounted payback (DP) were under consideration. A minimum attractiveness rate adjusted to the risk of emerging countries of 10.25% per year was considered. The viability of the project was verified, even when exposed to risk and uncertainty.

To date, despite the existence of the sustainability goals of the 2030 Agenda and the need for an energy transition, the results set is still quite far away from being achieved. The awareness of this situation moves many European countries to promote policies based on the use of renewable sources. This paper is aimed at illustrating the Italian legislative context, evaluating the effectiveness of the introduced incentives, according to parameters that affect the productivity of a photovoltaic system. It is also aimed at helping to bridge the gap linked to the relationship between incentives and energy transition, also with regard to renewables. The research focuses on an evaluation methodology, based on technical and economic standards and it is accompanied by a case-study. In order to analyze the productivity of the photovoltaic system, all the main input factors that could affect the technical and economic performance of the system were investigated. In particular, solar potential analysis, shading elements, installation place, azimuth, tilt of modules and technology. For the economic valuations, the discounted cash flow method was used. The results obtained show that some Italian regions, particularly those in the north, should prefer other forms of renewables, such as hydroelectric and geothermal, and that the FER1 decree is not suitable for the promotion of solar photovoltaics in some areas. The research shows also that policies on renewables should be calibrated according to the intrinsic features of the place where they are located and have to be related to the built heritage they will interface, in the light of technological and plant system aspects.

The COVID-19 pandemic caused profound impacts on the global economy, resulting in a sharp drop in carbon emissions as energy demand fell. The emissions reduction due to past extreme events often follows with a rebound after the economy recovers, but the pandemic's impacts on the long-term carbon emissions trend remain unknown. This study forecasts the carbon emissions of Group of Seven (G7) as developed countries and Emerging Seven (E7) as developing countries using socioeconomic indicators and artificial intelligence-powered predictive analytics to assess the pandemic's impacts on the long-term carbon trajectory curve and their progress toward achieving the Paris Agreement goals. Most E7's carbon emissions have strong positive correlations (> 0.8) with the socioeconomic indicators, whereas most G7's correlate negatively (> 0.6) due to their decoupled economic growth from carbon emissions. The forecasts show higher growth rates in the E7's carbon emissions after the rebound in the pandemic scenario compared to the pandemic-free scenario, while the impact on the G7's carbon emissions is negligible. The overall impact of the pandemic outbreak on long-term carbon emissions is small. Still, its short-term positive impact on the environment should not be misunderstood, and stringent emissions reduction policies must be implemented urgently to ensure the achievement of Paris Agreement goals.

Alternative fuels especially those produced in a green way are essential for meeting supplying the world's growing energy needs. Biodiesel is becoming more prominent to meet international maritime organization regulations, minimize reliance on fossil fuels, and lessen the rising harmful emissions in the maritime sector. Four different generations have been investigated in the production stage in which a wide range of fuel types have existed including biodiesel, bioethanol, and renewable diesel. To investigate all facets of biodiesel usage as a marine fuel, the SWOT-AHP method is utilized in this paper in which 16 maritime experts with an average of 10.5 years of experience participated. SWOT factors and sub-factors have been developed in light of the literature review focused on biomass and alternative fuels. The AHP method is utilized for data acquisition from specified factors and sub-factors according to their superiority to each other. The analysis demonstrates the main factors 'PW and sub-factors' IPW values, and CR values to calculate the local and global rank of factors. Results highlighted that "Opportunity" has the highest prominence among the main factors; however, "Threats" remain at the lowest level. Moreover, "Tax privilege on green and alternative fuels supported by the authorities" (O4) is the one with the highest weight compared to the other sub-factors. Noteworthy energy consumption will be fulfilled in the maritime industry in addition to the development of new-generation biodiesel and other alternative fuels. This paper will be a quite valuable resource for experts, academics, and industry stakeholders to lessen the ambiguity around biodiesel.

This study aims to propose a new process design, simulation, and techno-economic analysis of an integrated process plant that produces glucose and furfural from palm oil empty fruit bunches (EFB). In this work, an Aspen Plus-based simulation has been established to develop a process flow diagram of co-production of glucose and furfural along with the mass and energy balances. The plant's economics are analyzed by calculating the fixed capital income (FCI), operating costs, and working capital. In contrast, profitability is determined using cumulative cash flow (CCF), net present value (NPV), and internal rate of return (IRR). The findings show that the production capacity of 10 kilotons per year (ktpy) of glucose and 4.96 ktpy of furfural with a purity of 98.21 and 99.54%-weight, respectively, was achieved in this study. The FCI is calculated as United States Dollar (USD) 20.80 million, while the working and operating expenses are calculated as USD 3.74 million and USD 16.93 million, respectively. This project achieves USD 7.65 million NPV with a positive IRR of 14.25% and a return on investment (ROI) of 22.06%. The present work successfully develops a profitable integrated process plant that is established with future upscaling parameters and key cost drivers. The findings provided in this work offer a platform and motivation for future research on integrated plants in the food, environment, and energy nexus with the co-location principle.

Low-carbon development of China's power sector is the key to achieving carbon peaking and carbon neutrality goals. Based on the logarithmic mean divisor index (LMDI) model, considering the carbon transfer caused by inter-provincial electricity trading, this paper analyzes the influencing factors of CO emissions in the provincial power sector and uses K-means clustering method to divide 30 provinces into four categories to analyze the differences in regional carbon emission characteristics. In addition, by establishing different development scenarios, the carbon emission trends and emission reduction potentials of each cluster under different emission reduction measures from 2020 to 2040 are studied, in order to explore the differentiated emission reduction paths of each cluster. The results show that the contribution of influencing factors shows great differences in different provinces. Trends in CO emissions vary widely across scenarios. In the reference scenario, the CO emissions of each cluster will continue to increase; in the existing policy scenario, the total power industry will peak at 6.1Gt in 2030; in the advance peak scenario that puts more emphasis on the development of advanced technologies and renewable energy under the clean development model, the carbon emission peak will be brought forward to 2025, and the peak will be reduced to 5.2Gt. Finally, differentiated emission reduction paths and measures are proposed for the future low-carbon development of different cluster power industries, providing theoretical reference for the deployment of provincial-level emission reduction work, which is of great significance to the global green and low-carbon transformation.

Carbon capture storage and utilization is not a new technology, but its application to reduce CO2 emissions from the refinery sector is just now emerging as promising mitigation. This study will look closely at opportunities to match CO2 sources with potential sinks by matching carbon-capturing projects at Indian oil refineries with Enhanced Oil Recovery (EOR) operations at nearby oil fields in India. This study has identified four such pairings of source-sink matching along with the challenges the first of the kind implementation of CCSU technology in specific projects. The study concludes with a discussion on the way forward and policy implications for the commercial use of the CCSU in India.

It is a global challenge to achieve sustainable economic growth by improving the environment. The present study discussed the role of the financial development sector in achieving sustainable economic growth and environmental quality in South Asian countries from 1990 to 2020 by controlling labour force participation, globalization, industrialization, and the education sector. A feasible generalized least squares (FGLS) panel data econometric technique has been used to check the relationship among the variables. The results show that financial development has a U-shaped relationship with carbon emissions and economic growth. Furthermore, labour force participation, industrialization, globalization, and educational school enrolment significantly increase CO and economic growth. This study suggests that the governments of South Asian countries should take steps to increase economic growth. For this purpose, effective supervisory mechanisms of financial development through financial innovation, improving financial efficiency, maintaining financial stability, and reducing the environmental pollution.

Plastics are undebatably a hot topic of discussion across international forums due to their huge ecological footprint. The onset of COVID-19 pandemic has exacerbated the issue in an irreversible manner. Bioplastics produced from renewable sources are a result of lookout for sustainable alternatives. Replacing a ton of synthetic plastics with biobased ones reduces 1.8 tons CO emissions. Here, we begin with highlighting the problem statement-Plastic accumulation and its associated negative impacts. Microalgae outperforms plants and microbes, when used to produce bioplastic due to superior growth rate, non-competitive nature to food, and simultaneous wastewater remediation. They have minimal nutrient requirements and less dependency on climatic conditions for cultivation. These are the reasons for current boom in the algal bioplastic market. However, it is still not at par in price with the petroleum-based plastics. A brief market research has been done to better evaluate the current global status and future scope of algal bioplastics. The objective of this review is to propose possible solutions to resolve the challenges in scale up of bioplastic industry. Various bioplastic production technologies have been comprehensively discussed along with their optimization strategies. Overall studies discussed show that in order to make it cost competitive adopting a multi-dimensional approach like algal biorefinery is the best way out. A holistic comparison of any bio-based alternative with its conventional counterpart is imperative to assess its impact upon commercialization. Therefore, the review concludes with the life cycle assessment of bioplastics and measures to improve their inclusivity in a circular economy.

The following article explains the current condition of the photovoltaics sector both in Poland and worldwide. Recently, a rapid development of solar energy has been observed in Poland and is estimated that the country now has about 700,000 photovoltaics prosumers. In October 2021, the total photovoltaics power in Poland amounted to nearly 5.7 GW. The calculated technical potential of photovoltaics in Poland is 153.484 PJ (42.634 TWh). This would cover 26.04% of Poland's electricity needs. The main aim of the article is to assess the level of development of the photovoltaic market in Poland, the genesis of its creation, description of the current situation and determination of the development opportunities. As part of the aim, programs supporting the development of solar energy in Poland have been described and the SWOT analysis has also been performed. The strengths of photovoltaics include high social acceptance and low costs of photovoltaics system operation, while opportunities include rapidly increasing technological efficiency and decreasing cost of solar systems. On the other hand, weaknesses include the high costs of photovoltaics systems and the disparities in the amount of solar energy reaching the market during the year, whereas climate change and the coronavirus pandemic are threats. In 2020, PV became an investment hit in the energy sector and an economic driver in Poland. In the difficult time of two lockdowns caused by the global pandemic, domestic PV made a significant contribution to the maintenance of investment processes in the amount of PLN 9.5 billion and provided Poland with 35 thousand jobs. In 2020, 1.5% of the country's electricity came from PV sources. In 2021, it will be 3.5%, and by 2025, solar energy will provide approx. 10% of Poland's electricity. It is worth examining the development of photovoltaics from a broad and long-term perspective. The spectacular development of photovoltaics in Poland is due to hitting the right time window and reducing technology costs, but most of all, it is based on the cooperation of stakeholders and trust in the regulatory environment.

Universal environmental policies adopt strategies that enhance and encourage the production and usage of electric vehicles (EVs). Universal cooperation is evident in the framework of agreements or protocols so as to successfully lead countries towards the predetermined goals. The question is whether this trend can reduce global warming or CO emissions worldwide. By adopting game theory, this study analyses electricity carbon life cycle in leading EV countries. Results show that although the spread of EVs in Europe and the USA can mitigate carbon emissions, the production and use of electric vehicles in some countries, such as China and India, become a new source of such emissions. This reverse effect is due to the emission of greenhouse gases from electricity sources in these countries. Game theory also suggests that countries with unclean electricity sources should reconsider their plans to produce and use EVs. This study confirms that although carbon emission and global warming are global problems, regional and local policies can be substituted with a single comprehensive approach for an effective means of CO emission reduction.

The adoption of novel transport options such as ethanol blended fuel (E85) vehicles, electric vehicles (EV), and compressed natural gas (CNG) vehicles to replace conventional petrol (gasoline) and diesel vehicles is not yet well understood. This work develops a system dynamics (SD) model to study the adoption of these novel options for private transport needs in India as a function of technology performance, cost, and other sector specific features. For EVs, expected growth in battery technology and the inconvenience due to lack of charging infrastructure are considered. Since ethanol production sector is still scaling up, model captures the inter-relationships between demand, supply, producer's profit, and investment in capacity increase. The growth in compressed biogas (CBG) plants and inconvenience due to lack of gas refilling stations are considered for CNG vehicles. For petrol and diesel, the effect of demand on consumer prices and its effect on ownership cost is modelled. A multi-multinominal logit model is used to capture selection of transport option as a function of total ownership costs. Model simulations are performed till 2050, and quantify the adoption trends as well as resulting total greenhouse gas emissions considering life cycle perspective for all the technological options. Simulation results show that E85, EVs and CNG vehicles would constitute 34 % of total private vehicle stock by 2050, resulting in 668.75 million tonnes of CO emissions. The targets set by the government for EV adoption and blending rate of ethanol will not be achieved, and significant improvement is costs and infrastructure are needed. Various policy options to improve adoption of new options are explored, identifying the technology development targets.

The COVID-19 crisis has brought unprecedented challenges to many sectors, including the built environment. The construction and demolition (C&D) waste management and recovery industry is an essential service provider to this sector. Like other industries, this industry has been affected by the pandemic in many ways. However, in Australia, this impact has not been thoroughly investigated. This study, therefore, explores COVID-19 impacts on the Australian C&D waste recovery and construction industry as the major waste consumer and generator. To achieve this aim, a literature review and a series of semi-structured interviews were conducted with 27 participants representing five stakeholder groups (government, construction, waste recovery, material supplying and consultancy) across five Australian states. The research findings established that there is a critical need for leveraging digital technologies, developing business contingency plans, creating coalitions between government and industry, and diversifying supply chains to reduce supply chain risks. This study also uncovered a range of targeted responses and recommendations to manage pandemic-induced disruptions and improve the circular economy in the industry. Our findings can immediately assist industrial practitioners and government decision-makers in managing the impacts of COVID-19 on the waste recovery activities in C&D waste and other waste streams.

This paper presents an overview for the Special Issue (SI) of Clean Technology and Environmental Policy journal (CTEP), and it includes accepted papers from 16th Conferences on Sustainable Development of Energy, Water and Environment Systems (SDEWES) held from October 10-15, 2021, in Dubrovnik, Croatia. Considering CTEPs policy of high-quality research papers, guest editors have invited 35 research articles, presented at the SDEWES 2021 conference. After a vigorous review process, 12 papers have been accepted for publication in this special issue. All 12 accepted papers are briefly presented in this overview together with a wider view that presents research efforts within the SDEWES community published through previous SDEWES special issues.

Atmospheric nitrogen oxides ( ) are key pollutants and short-lived climate forcers contributing to acid rain, photochemical smog, aerosol formation and climate change. Exposure to nitrogen dioxide ( ) emitted mainly from transportation, causes adverse health effects associated with respiratory illnesses and increased mortality even at low concentration. Application of titanium dioxide ( )-based photocatalysis in urban environment is a new air cleaning solution, activated by sunlight and water vapour to produce OH radicals, able to remove and other pollutants from the planetary boundary layer. This study is a large-scale evaluation of removal efficiency at a near-road environment with applied photocatalytic NOxOFF™ technology on an urban road west of Copenhagen, thus supporting local municipality in meeting their clean-air Agenda 2030. The photocatalytic NOxOFF™ granulate containing nanoparticles was applied on an asphalt road in July 2020 and ambient was measured during a six-month monitoring campaign. It is the first monitoring campaign carried out at this road and specific efforts have been devoted to evaluate the reduction in ambient levels with NOxOFF™-treated asphalt. Several methods were used to evaluate the photocatalytic effect, taking into account analysis limitations such as the short reference period prior to application and the highly uncertain measurement period during which SARS-CoV-2 lockdown measures impacted air quality. There was no statistically significant difference in concentrations between the reference period and the photocatalytic active period and NO removal efficiency resulted in (± 1.27). An upper limit removal of 17.5% was estimated using a kinetic tunnel model. While comparison with COPERT V street traffic model projection was roughly estimated to decrease by 39% (± 38%), although this estimate is subject to high uncertainty. The observed annual mean concentration complies with Frederiksberg clean-air Agenda 2030 and air quality standards.