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Growing environmental concerns have driven the installation of renewable systems. Meanwhile, the continuous decline in the levelized cost of energy (LCOE), alongside the decreasing cost of photovoltaics (PVs), is compelling the power sector to accurately forecast the performance of energy plants to maximize plant profitability. This paper presents a comprehensive analysis and optimization of a hybrid power generation system for a remote community in the Middle East and North Africa (MENA) region, with a 10 MW peak power demand. The goal is to achieve 90 percent of annual load coverage from renewable energy. This study introduces a novel comparison between three different configurations: (i) concentrated solar power (parabolic troughs + thermal energy storage + steam Rankine cycle); (ii) fully electric (PVs + wind + batteries); and (iii) an energy mix that combines both solutions. The research demonstrates that the hybrid mix achieves the lowest levelized cost of energy (LCOE) at 0.1364 USD/kWh through the use of advanced transient simulation and load-following control strategies. The single-technology solutions were found to be oversized, resulting in higher costs and overproduction. This paper also explores a reduction in the economic scenario and provides insights into cost-effective renewable systems for isolated communities. The new minimum cost of 0.1153 USD/kWh underscores the importance of integrating CSP and PV technologies to meet the very stringent conditions of high renewable penetration and improved grid stability. [ABSTRACT FROM AUTHOR]

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During the last few years, electric and hydrogen vehicles have become an alternative to cars that use internal combustion engines. The number of electric and hydrogen vehicles sold has increased due to support from local governments and because car manufacturers will stop the production of internal combustion engines in the near future. The emissions of these vehicles while being driven are zero, but they still have an impact on the environment due to their fuel. In this article, an analysis of carbon dioxide (CO2) emissions for two types of vehicles: battery electric vehicles (BEVs) powered by electricity and fuel cell electric vehicles (FCEVs) powered by hydrogen, is presented. The analysis considers different values for the mix of power generation and hydrogen production options in comparison to other studies. The CO2 emissions were calculated and compared for the two types of vehicles. The results show that the CO2 emissions of BEVs are lower when compared to FCEVs if the hydrogen is obtained from pollutant sources and is higher if the hydrogen is obtained from nuclear power and renewable energy sources. When compared to conventional combustion engine vehicles, BEVs have lower CO2 emissions, while the emissions of FCEVs are dependent on the hydrogen production method. [ABSTRACT FROM AUTHOR]

Power mix risk management is a crucial aspect of energy sector decision-making. Amidst disruptive events, emerging economies struggle to sustain recovery and long-term progress, necessitating a focus on mitigating the impact of major incidents. However, power mix risk management often overlooks the pathways through which the system's structure is exposed to risks. Using a qualitative three-step approach, this study investigated inherent risks of the structure and managerial practices Belize's power mix, mapping its structure and actors, identifying underlying causes and exposure pathways, classifying risks into five major dimensions, and characterizing each dimension as complex, uncertain, or ambiguous. Belize's structural choices presented systemic paradoxes such as the application of fixed-cost models for volatile local renewable sources, the actor's ambiguity on key elements of the supply system, including reliance on electricity imports and the retirement of local supply assets, being perceived as a lack of commitment, increasing the threat of investing in the domestic supply market, and regulations seeking to attract investment and de-risk electricity supply projects that in turn locked-out new investment and technologies due to market size. Further, system mitigation practices were limited and primarily based on regulatory interventions, with risk dimensions varying and sometimes related, suggesting a need for expanded and consolidated mitigation styles. • Growing need to identify, measure, verify, and manage risks. • Assesses the inherent risks of the structure and managerial practices • Mapping actors, identifying exposure pathways, classifying and characterizing dimensions • Systemic paradoxes in decision-making and actor ambiguity in policy • Mitigation practices largely limited to regulatory intervention [ABSTRACT FROM AUTHOR]

Achieving carbon neutrality without innovative mitigation measures can be challenging. Power-to-X (P2X), a technology for capturing and utilizing carbon, has become an emerging solution for offsetting CO 2 emissions. However, the mitigation potential of P2X is dependent on various factors, and P2X cannot perform a mitigation role with the national electric grid in our scenario analysis. This study aims to examine the requirements for P2X to achieve carbon neutrality. We establish a mathematical mechanism to assess the mitigation potential of P2X and examine the role of various factors in reducing GHG emissions. We found that energy share in electricity production decides the pace of emission reduction; the cleaner the energy share, the faster the emissions reach the inflection point of the mitigation pathways. Adoption rate also plays a key role to amplify inclination of emission paths. As a result, P2X could immensely reduce CO 2 emissions regardless of adoption rates, if the clean energy share is above 80% without coal. The relationship between these factors and mitigation potential of P2X concludes that this emerging technology is a double-edged sword and requires meticulous planning for its adoption. • Establishing a mathematical mitigation mechanism for P2X. • Mitigation pathways of P2X delineate concave down patterns. • The cleaner the energy mix, the faster the emission reaches to the inflection point. • High adoption rate of P2X amplifies the inclination of the emission path. • P2X functions as mitigation measure if the clean energy share exceeds 80%. [ABSTRACT FROM AUTHOR]

MilliporeSigma recently introduced a new magnetically coupled single-use mixing system (Mobius® Power MIX) for more efficient mixing of buffers and media in biopharmaceutical applications. Experimental and computational fluid dynamics (CFD) assessments were performed on the Power MIX 100 system to understand product quality impact, shear, and mixing efficiency. It was interesting to note slightly higher submicron (0.4-1 μm) and subvisible (1-54 μm) particle formation at the lower mixing speed (50 RPM) compared to higher mixing speeds (100/200 RPM). Mixing speed and time showed negligible impact on the other product quality attributes tested, including protein concentration, turbidity, general appearance, purity, and soluble aggregates. The CFD simulations provided useful information with respect to the impact of batch size (20-100 L), viscosity (2-50 cP), and impeller speed (100-300 RPM) on mixing time (mixing time ranged from 10 to 365 s) and shear (maximum shear rate was found to be localized around the impeller and it was about 30,260 s−1, whereas the average shear rate ranged from 4 to 36 s−1). Statistical analysis of the CFD results showed that natural-log transformation and quadratic fitting were found to be suitable statistical models to predict mixing time and shear within the design space of the parameters assessed in the present study. [ABSTRACT FROM AUTHOR]

To minimize the adverse effect of salinity and improve of productivity and chemical constituents of wheat grown in sandy soil by using foliar applications two field experiments were laid out in the Desert Experimental Station, Faculty of Agriculture, Cairo University in Wadi El-Natroon, El-Beheira Governorate, Egypt during 2015/2016 and 2016/2017 seasons to study the response of three wheat cultivars (Gemmiza12, Sakha93 and Misr2) to foliar application with humic acid, Power Mix, zinc sulphate and putrescine compared with a control treatment on some growth parameters, yield and its components as well as chemical composition content compared with untreated wheat plants. A split-plot design in a randomized complete block arrangement was used with three replications. The main plots were allotted to the seven levels of foliar application and three Egyptian commercial varieties of wheat were devoted to sub-plot. The results indicated significant varietal differences response to the above mentioned treatments in most of traits under study. Misr2 was superior in plant height, fresh and dry weights, root length, No. of spikes/plant, spike weight/plant, straw and grain yields/plant, grain yield/fed, total grain sugar and total free amino acids (FAA) contents. The use of putrescine gave the best results in most of growth traits under study. Particularly plant height, and plant fresh and dry weights. Use of power mix recorded the best results regarding (straw weight/plant, grain weight/spike and spike weight/plant. Sakha93 gave the highest average of grain N, K and shoot N, P and K. The application of 200 ppm putrescine recorded the same results while Misr2 gave the highest reading in shoot N and P. Finally Sakha93 was superior in phenol, total FAA in shoot and grains in phenol content while Misr2 recorded the highest total sugar and total FAA in grain contents. [ABSTRACT FROM AUTHOR]

Abstract The rise of renewable and clean power is seen as the key to alleviating environmental problems, especially for the emerging country heavily dependent on fossil energy such as China, which treats the clean-oriented generation mix as the inevitable part of power reform and improvement of environment. Thus, this paper studied the contribution of non-fossil fuel power generation to CO 2 emission reduction from electricity sector for 30 provinces over the period 1991–2015. The empirical results of panel quintile regression model show that, a 1% increase of non-fossil fuel power generation share can generally reduce electricity-related CO 2 emissions by over 2%, however, those effects appear heterogeneous among quantiles from low to high. Moreover, comparing the two sub-samples, i.e., the pre-reform period (1991–2002) and post-reform period (2003–2015), the separate estimates indicate the emission reduction effects of non-fossil fuel power generation are more obvious even for each corresponding quantile in the post-reform period, implying the essentiality of market-oriented and clean-oriented power reform. Graphical abstract Fig. Provincial electricity-related carbon emissions in 1991 and 2015 (10 thousand tons). Image Highlights • The panel quantile regression is employed to capture unobserved heterogeneity. • A 1% increase of non-fossil electricity share averagely reduces electricity-related CO2 emissions by up to 2%. • The emission reduction effect of non-fossil power generation seems to be more obvious in the post-reform period. • Clean-oriented generation mix is effective on CO2 emission reduction. [ABSTRACT FROM AUTHOR]

The growing energy crisis and severe atmospheric pollution have put much pressure on the Chinese government and resulted in a lot of revolutionary changes. Considering the upcoming new environmental and carbon tax, how would the tax reform affect the power sector; which types and how much of the different power generation technologies would be added are important questions that need to be answered by decision makers. In this study, a deterministic optimization model is proposed for determining the optimal power mix through the introduction of environmental and carbon taxes. A case study of Hebei Province in China is provided to illustrate the effects of these two taxes. The capacity additions of different generation technologies, air pollutants and CO 2 emission amounts, system costs, and regional power security under different tax levels are profoundly examined. The modeling results indicate that such tax policies could significantly improve to the power mix adjustment as well as the quality of the ambient air quality. Higher tax levels would promote the development of renewable power generation. Meanwhile, different degrees of CO 2 and air pollutant emission reduction can be achieved. The modeling results could help the decision makers identify the satisfactory tax levels in the future. [ABSTRACT FROM AUTHOR]

West African countries’ energy and climate policies show a pronounced focus on decarbonising power supply through renewable electricity (RE) generation. In particular, most West African states explicitly focus on hybrid mixes of variable renewable power sources—solar, wind and hydropower—in their targets for the electricity sector. Hydropower, the main current RE resource in West Africa, is strongly sensitive to monsoon rainfall variability, which has led to power crises in the past. Therefore, solar and wind power could play a stronger role in the future as countries move to power systems with high shares of RE. Considering the policy focus on diversified RE portfolios, there is a strong need to provide climate services for assessing how these resources could function together in a power mix. In this study, climate data from the state-of-the-art ERA5 reanalysis is used to assess the synergies of solar photovoltaic (PV) and wind power potential in West Africa at hourly resolution. A new metric, the stability coefficient C _stab , is developed to quantify the synergies of solar PV and wind power for achieving a balanced power output and limiting storage needs. Using this metric, it is demonstrated that there is potential for exploiting hybrid solar/wind power in a larger area of West Africa, covering more important centers of population and closer to existing grid structures, than would be suggested by average maps of solar and wind resource availability or capacity factor for the region. The results of this study highlight why multi-scale temporal synergies of power mixes should be considered in RE system planning from the start.

The simple action of filling a glass of water at home generates a greenhouse gas emission elsewhere, because it is necessary to spend electricity to treat the water, make it potable and then pump it to the point of consumption. These daily activities, seemingly clean, need electric energy and they carry out a human-induced greenhouse gas emission. Generation of electricity has a significant effect on the inventory of emissions and environmental impacts due to the large differences in the power generation sources used. This paper aims to shed light on the methodological challenge and develop a necessary simplified methodology to illustrate the importance of the power generation mix in urban greenhouse emissions. The electrical mix is a figure that expresses the carbon emissions associated to the electrical power generation, so it is an indicator of the suitability of the sources used for electrical power production. The smaller the mix, the higher is the contribution of low carbon emission sources. The methodology is explained, applying it to Madrid, assessing the greenhouse gas emission per kWh of electricity generated. The proposed estimation covers emissions of CO 2 equivalent (KgCO 2eq ), including the equivalence between each greenhouse gas and carbon dioxide considering a prevalence of 100 years. [ABSTRACT FROM AUTHOR]

Integration of renewable sources into Brazil's power mix is desirable and necessary. The main benefit from these energy sources is maintaining greenhouse gas emissions at low levels. Nevertheless, high penetration of these energy sources into the power mix can lead to many problems, for instance, intermittency in power generation. There are some mechanisms which can be implemented to mitigate intermittency and allow a higher level of participation of these energy sources in the generation mix. One such mechanism is utilizing Energy Storage Systems (ESS). The goal of this paper is to perform a study to find the best ESS options using Multi-criteria Decision Analysis. Moreover, an examination regarding Hydro Power Plants' reservoirs as an ESS is accomplished through a case study using three of Brazil's significant Hydro Power Plants. [ABSTRACT FROM PUBLISHER]

Emerging economies account for a fast-growing share of the global energy market. In particular, energy use in China has become significant from both economic and environmental standpoints. This trend makes it necessary to balance the need for affordable, reliable electricity supply with the need to ensure that the power infrastructure is environmentally sustainable. As such, this paper presents a multi-dimensional pinch analysis (MDPA) of the power generation sector in China; the analysis considers five key indices: carbon footprint, energy return on investment (EROI), water footprint, land footprint, and risk to humans. By simultaneously quantifying five different indices under a common methodological framework, we are able to coherently assess the impact on five different environmental concerns. This approach provides a more complete picture of the true environmental impact of China's power sector. This information can thus help policymakers avoid the problem of shifting environmental impacts to other domains, which can occur when the analytic procedure used focuses on a single environmental dimension. [ABSTRACT FROM AUTHOR]

This paper presents a techno-economic optimization procedure for selecting the best energy mix of renewable energy sources to meet the predefined power demands of an isolated community. The simulation model, based on Trnsys software, incorporates the technical characteristics of each plant component, site meteorological data, investment, and operation and management costs. An optimization procedure selects the best combination and sizing of each generation system and energy storage capacity to achieve the minimum value of Levelized Cost of Electricity (LCOE) for different renewable energy fractions from 40% to 100%. A case study for a new renewable community with a peak load of 50 MW in the Tabuk region, Kingdom of Saudi Arabia (KSA), is presented and discussed. The implementation of a complete renewable system raised the LCOE trend to 0.156 USD/kWh from 0.081 USD/kWh. The optimal renewable penetration for the analyzed case is approximately 80%, with an overall LCOE of 0.092 USD/kWh. The optimized power mix highlights the possibility of providing clean energy without a huge cost burden. • High penetration of renewables in remote communities requires an optimized energy mix. • PV and wind coupled with CSP benefit from increased energy dispatchability. • Thermal energy storage enables a reduction in LCOE in energy mix with high renewables content. • The load-following operation requires the use of high storage capacity. • The LCOE is minimized by minimizing the use of electric storage at utility-scale. [ABSTRACT FROM AUTHOR]

The energy transition driven by the need of a deep decarbonization to limit the world temperature rise requires coordinated actions across the whole energy sector. Among other measures, the strong development of renewable energy sources in the power sector is gaining momentum in different parts of the world. The possibility of producing low-carbon electricity leads to a renovated interest in increasing electricity penetration in final sectors, especially in transport and buildings heating. However, a large share of renewable electricity comes from non-dispatchable sources, notably wind and solar PV, and their daily and seasonal variability needs to be matched with the demand profiles of those sectors. In particular, the charge of electric vehicles shows a relatively constant demand on a seasonal basis while attention must be paid on the daily operational logic to fully exploit available power from solar and/or wind. On the other hand, the operation of heat pumps for building heating shows a strong seasonality that may be an issue in countries that have a larger renewable production during summer. This research work is focusing on this specific issue, with the aim of improving the common practice of evaluating energy consumption and emissions on an annual basis, thanks to a detailed analysis based on hourly time-step, both for the electricity generation mix and for the heat pumps demand. To increase the significance of the results, different countries across Europe have been analyzed and compared. • The performance of different heat pumps is evaluated with high time resolution. • The seasonality of the renewable generation and the heat pump demand may not match. • An accurate electricity mix is calculated and compared with an average annual value. • High penetrations of renewables in power generation lead to higher differences. [ABSTRACT FROM AUTHOR]

• Estimates the choice probability of alternative fuel vehicles. • Analyzes greenhouse gas emissions in the transport sector. • Forecasts that greenhouse gas reduction is only 4.7% of 2030 target. • Finds that fuel cell electric vehicles affect electric vehicle market share. • Proposes the segmentation between green cars for efficient investment and diffusion. Electric Vehicles (EVs) and Fuel Cell Electric Vehicles (FCEVs) are expected to play an important role not only as solutions to the environmental problem but also as the future demand for automobiles. However, the eco-friendliness of these vehicles cannot be judged simply on the basis of emissions of harmful exhaust gas during operations. This is because electricity and hydrogen which serve as fuels of EVs and FCEVs, result in the generation of greenhouse gas (GHG) which must also be taken into consideration. Previous studies which examined GHG emissions of EVs and FCEVs, did so from a well-to-wheel perspective, using cross-sectional data on only one type of fuel. Meanwhile, this paper approaches GHG emissions caused by EVs and FCEVs by examining the power mix and resulting change of market share of EVs and FCEVs in South Korea. In numerical terms, the estimated GHG reduction is 122,441 tCO2-e, which constitutes only 4.7% of the sector-wide target of 30.8 million tCO2-e. Furthermore, although the introduction of FCEVs helps to reduce GHG, it also simultaneously affects the EV market share. Therefore, it is necessary to clarify the segmentation of FCEVs and EVs to optimize efficient infrastructure investment and a stable diffusion of environment-friendly vehicles. [ABSTRACT FROM AUTHOR]

The environmental impact of battery electric vehicles (BEVs) largely depends on the environmental profile of the national electric power grid that enables their operation. The purpose of this study is to analyze the environmental performance of BEV usage in Korea considering the changes and trajectory of the national power roadmap. We examined the environmental performance using a weighted environmental index, considering eight impact categories. The results showed that the weighted environmental impact of Korea's national power grid supply would increase overall by 66% from 2015 to 2029 using the plan laid out by the 7th Power Roadmap, and by only 33% from 2017 to 2031 using the 8th Power Roadmap plan. This change reflects the substantial amount of renewables in the more recent power mix plan. In 2016, BEV usage in Korea resulted in emissions reductions of about 37% compared with diesel passenger vehicles, and 41% compared with gasoline vehicles per kilometer driven (100 g CO2e/km versus 158 g and 170 g CO2e/km, respectively) related to transportation sector. By 2030, BEV usage in Korea is expected to achieve a greater emissions reduction of about 53% compared with diesel vehicles and 56% compared with gasoline vehicles. However, trade-offs are also expected because of increased particulate matter (PM) pollution, which we anticipate to increase by 84% compared with 2016 conditions. Despite these projected increases in PM emissions, increased BEV usage in Korea is expected to result in important global and local benefits through reductions of climate-changing greenhouse gas (GHG) emissions. [ABSTRACT FROM AUTHOR]