This research addressed a need for technical evaluation of the oceanic scenario of Panama for the use of Ocean Thermal Energy Conversion (OTEC). Its bathymetry and location can potentially lead to the exploitation of OTEC, diversifying the energy matrix and helping achieve sustainability. Nevertheless, site selection for OTEC can be a complex task since it involves various alternatives, with different quantitative and qualitative criteria, which may conflict in some cases. Optimization and multiple criteria (MCD) methods have been used lately to address these issues; however, their use is still limited. Here, Analytic Hierarchical Analysis (AHP) is proposed as a MCD method for site selection. Six sites of interest were considered as the alternatives for a plant installment. These sites were chosen, excluding the environmentally and aboriginal protected areas. The quantitative criteria considered were surface and deep-water temperatures, coastline distance, gross and net efficiency. Tho... [more]

Energy-environmental planning for road transportation involves a vast investigation of vehicles’ technologies and electricity production. However, in developing countries where the public transportation sector is growing quickly, energy-environmental planning is urgently needed. This paper evaluates the future electricity demand, as well as fuel consumption and CO2 emissions reduction, due to the operation of an expected increasing number of electric vehicles (EVs) in Pakistan. The planning of EVs up to 2040 is performed with the ePop simulator that calculates the future EVs’ electricity demand, while EnergyPLAN® assesses the expected new power capacities. Two scenarios are investigated by penetrating 30% and 90% of 2/3 electric wheelers and cars by 2030 and 2040 compared to 2020, respectively. To fulfill the expected energy demand, PV in the daytime and the national electric grid at nighttime are here considered. Finally, a 9 GW of PV capacity is needed to satisfy the EVs’ electricity... [more]

The present study explores the impact of renewable energy usage, economic progress, urbanization, and trade on carbon emissions in Bhutan. The stationarity among the variables was tested by employing the two unit root tests by taking the annual data series variables from 1982−2020. A symmetric (ARDL) technique was utilized to analyze the associations among variables with short- and long-run estimations. In addition, the cointegration regression method using FMOLS and DOLS was used in this investigation to discover the robustness of the study variables. Findings showed that via long-run assessment the variables renewable energy consumption, urbanization, and trade have adverse connections with CO2 emission, while the variable economic progress shows a constructive linkage with carbon emission. However, the short-run assessment showed that the variable economic growth has a positive impact on carbon emissions. Further, the variables renewable energy consumption, urbanization, and trade h... [more]

The integration of power-electronics-based power plants is developing significantly due to the proliferation of renewable energy sources. Although this type of power plant could positively affect society in terms of clean and sustainable energy, it also brings adverse effects, especially with the stability of the power system. The lack of inertia and different dynamic characteristics are the main issues associated with power-electronics-based power plants that could affect the oscillatory behaviour of the power system. Hence, it is important to design a comprehensive damping controller to damp oscillations due to the integration of a power-electronics-based power plant. This paper proposes a damping method for enhancing the oscillatory stability performance of power systems with high penetration of renewable energy systems. A resilient wide-area multimodal controller is proposed and used in conjunction with a battery energy storage system (BESS) to enhance the damping of critical modes... [more]

In this article, a comprehensive review of the computational fluid dynamics (CFD)-based modeling approach for thermoacoustic energy conversion devices is proposed. Although thermoacoustic phenomena were discovered two centuries ago, only in recent decades have such thermoacoustic devices been spreading for energy conversion. The limited understanding of thermoacoustic nonlinearities is one of the reasons limiting their diffusion. CFD is a powerful tool that allows taking into consideration all the nonlinear phenomena neglected by linear theory, on which standard designs are based, to develop energy devices that are increasingly efficient. Starting from a description of all possible numerical models to highlight the difference from a full CFD method, the nonlinearities (dynamic, fluid dynamic and acoustic) are discussed from a physical and modeling point of view. The articles found in the literature were analyzed according to their setup, with either a single thermoacoustic core (TAC) o... [more]

Today, the growing Asia-Pacific population causes a dramatic growth in energy supply to meet energy demand. The rapid rise in energy demand is causing concern in the region. Thus, the present study scrutinizes the effect of energy policy involvement in steering-up renewable energy development by empirically assessing the role of policy instruments in encouraging residential-scale and commercial-scale photovoltaic (PV) systems. The analysis is performed using a fixed effects estimator on a selected range of policy approaches (market-pull policies and tax incentives) and a technology-push policy (capital grants) in selected Asia-Pacific countries between 1998 and 2015. The return on investment is estimated to measure the incentives of feed-in tariff (FIT) tariff policies for both residential-scale and commercial-scale PV systems. This study has shown the importance of a strategic combination between technology-push and market-pull policies as complementary to adopting technology and incr... [more]

Non-renewable-resource consumption and global greenhouse-gas (GHG) emissions are critical issues that pose a significant threat to sustainable development. Solar energy is a promising source to generate renewable energy and an appealing alternative electricity source for households. The primary goal of this research is to detect the rooftops that have no solar photovoltaic (PV) system deployed on them but that receive moderate to high solar-energy radiation using the Geographic Information System (GIS) and deep-learning techniques. Although various studies have been conducted on this subject, not many addressed these two issues simultaneously at a residential level. Identifying the installed solar PV systems in a large area can be expensive and time-consuming work if performed manually. Therefore, the deep-learning algorithm is an emerging alternative method to detect objects using aerial images. We employed the Single-Shot-Detector (SSD) model with the backbone of residual neural netw... [more]

Sustainable technologies, including clean energy in manufacturing and green and reverse logistics, generate conditions for industry development and future growth with the implementation of Industry 4.0 technologies and innovations in the context of sustainable development goals (SDGs). The objective of the article is to identify and analyse the potential of sustainable technologies in synergy with Industry 4.0 innovations and renewable energy initiatives in manufacturing and logistics in the context of SDGs. Qualitative analysis was performed on 105 enterprises of various business sizes, in several regions of Slovakia, within various industry sectors, and within geographical coverage. Based on the summarised results, we can state that more than 82% of surveyed enterprises implement the SDGs. Currently, more than 70% of enterprises prefer environmental aspects in business management. Based on the results, we find a significant relationship between the environmental management of the ent... [more]

Research activity in the field of combined cooling heating power (or trigeneration) systems with high renewable energy source (RES) contributions has increased rapidly over the last few years, in line with the European Union legislation about energy communities. However, technical challenges arise regarding the synergetic, sustainable and optimal integration of RES in local energy systems. In the present study, the operation of a trigeneration system located in the student residences of Democritus University of Thrace in Greece is examined. The system involves a combination of highly promising renewable and storage technologies, including solar thermal energy and biomass for heat generation, hot water tanks for thermal energy storage, absorption refrigeration for cooling, along with Organic Rankine Cycle and photovoltaic systems for electricity generation. System modeling and simulation have been implemented in Dymola environment with the use of Modelica equation-based modeling languag... [more]

The growth of renewable energy facilities worldwide creates new challenges for sustainable regional development. Unregulated investment flows in the green energy sector cause disparities in the deployment of various renewable energy technologies, worsen the ability to balance national energy systems, etc. This article is the first comprehensive study that offers a methodology for multifactor modeling of investment flows in regional green energy deployment considering the priorities of national, regional, and local authorities within the sustainable development concept. The proposed methodological approaches help (1) determine the types of renewable energy technologies for priority development in the region, (2) select specific green energy projects to receive budgetary support on territories, and (3) form the optimal mechanism for budget financing distribution on regional development of renewable energy technologies. The modeling factors include natural conditions and resource base of... [more]

Transition to green energy is the dominant process in the electricity sector globally, including in North-East Asia (NEA). The interstate power grid expansion in the NEA will facilitate the large-scale development of intermittent and uncertain green generation. This paper is aimed at considering the structural and operating features and effectiveness of a potential NEA power grid with large-scale penetration of renewables. A computing and geo-information system provides collection, processing, storage, and geo-visualization of technical and economic data. It incorporates a mathematical model for the optimization of the expansion and operation of power systems. Benefits (including saving the capacity, investment, fuel cost, and total cost) of power interconnection have been estimated in the study. Transfer capability required for the interstate electric ties was calculated and proved quite significant. A tax on greenhouse gases emission from thermal power plants, including carbon dioxid... [more]

The developed production of heat (steam) by Farmutil Company enables use of renewable energy from biofuel meat-bone meal which is incinerated in rotary kilns utilising vapours and odours from its production, instead of natural gas, to ensure Farmutil’s own needs for heat. The transformation of existing district heating in Piła city (currently using coal) into a fourth generation district heating system was proposed, predicting the use of heat (hot water) after combustion of biofuel meat-bone meal as district heating in the city of Piła. The maximum possible surplus amount of heat that can be produced at Farmutil exceeds the needs for the district heating demands of the city of Piła (860,200 GJ/y) by 53.2% at a meat-bone meal burning scale of 150,000 t/y. The use of 52,000 t/y of meat-bone meal for district heating production also results in an increase in incomes through the sale of hydroxyapatite ash from its combustion, amounting 1.638 million EUR/y. The closure of the coal-fired hea... [more]

With the integration of large-scale renewable energy into the power grids, cross-regional power trade can play a major role in promoting renewable energy consumption, as it can effectively achieve the optimal allocation of interconnected power grid resources and ensure the safe and economic operation of the power grid. An optimization model on a mid/long-term scale is established, considering the relationship between the renewable energy absorption interval and the regulation of resources in the system. The model is based on the load block curve and the renewable energy power model, considering the maintenance constraints of conventional units, the operation constraints of conventional units and renewable energy units, cross-regional power trade constraints and system operation constraints. By analyzing the results of the adapted IEEE RELIABILITY TEST SYSTEM (IEEE-RTS), the validity of the model and method proposed in this paper is proven. The results show that the coordinated optimiza... [more]

The move towards a greener energy mix to fight climate change propels investments in converter-interfaced resources such as wind and photovoltaics, energy storage systems and electric vehicles. The ongoing evolution of the power system is occurring at a very fast pace, challenging transmission and distribution system operators to seek solutions that are not only adequate for this moment but also for future scenarios. Ongoing research in the fields of power electronics, power systems and control aims at developing control strategies that will help the energy transition to occur, while keeping a stable, secure and reliable power system. The objective of this paper is to present a critical review of the control strategies developed for grid-connected power converters found in renewable energy systems, energy storage systems and electric vehicles. The impact of grid-connected converters on the stability of power grids is also reviewed, highlighting the promising control strategies for enha... [more]

The problem of rising energy prices stems from the weakening of economies operating in the realities of the COVID-19 coronavirus pandemic, as well as from the rising cost of CO2 emission allowances in connection with the European Union’s environmental policy. The outbreak of war in Ukraine has deepened the energy crisis in European countries, which, to a significant extent, benefit from hydrocarbon resources imported from Russia. This problem is particularly acute in countries that are heavily dependent on conventional forms of energy production (e.g., Poland). In light of the problems observed, the need to develop a market for renewable energy has become more urgent than ever. Although this problem affects a number of countries, the authors of the study decided that it is particularly important in the region of the countries neighbouring the line of the ongoing armed conflict in Ukraine, i.e., Poland and the Baltic States (Lithuania, Latvia and Estonia). The choice of the research are... [more]

Energy management and monitoring systems are significant difficulties in applying microgrids to smart homes. Thus, further research is required to address the modeling and operational parts of the system’s future results for various applications. This paper proposes a new technique for energy management in a microgrid using a robust control approach and the development of a platform for real-time monitoring. The developed controller is based on a fuzzy logic method used in the energy Internet paradigm with connected distributed generators (DGs) in the microgrid. The developed method regulates the power flow of the microgrid, and frequency/voltage regulation improved the load-management performance and monitoring system using the ThingSpeak platform for real-time data analysis. The MATLAB. simulation results show the feasibility and effectiveness of the proposed strategy and the introduced approach in microgrid control under various operating conditions. Additionally, the results show t... [more]

This paper shows an increase in the robustness of a DFIG-based wind energy system when a predictive-repetitive controller in the dq reference frame is used for the control of the rotor current. This designing approach proposes a model predictive control with a receding horizon technique that uses the frequency decomposition of the reference signal as a filter. Furthermore, an augmented space-state model from the original plant model is obtained, and its implementation is addressed from the perspective of normal operating conditions of DFIG in wind energy systems. Additionally, this repetitive controller increases the robustness of the predictive control when a mismatch in machine parameters is considered. Experimental results presented in this paper endorse the advantages of this controller.

Buildings play a significant role in terms of energy consumption and polluting emissions production across Europe and this huge contribution to consumption and environmental impact becomes even more alarming when attention is switched from single buildings to entire urban systems. Although great efforts have been made to support energy efficiency investments, distrust and suspicion are shared attitudes among private investors (and stakeholders in general) towards large-scale implementation of these kinds of projects. Within this framework, on-bill schemes were implemented in the United States more than 30 years ago. In particular, on-bill energy efficiency is a method of financing energy efficiency improvements that uses the utility bill as the repayment vehicle. A detailed analysis of on-bill schemes is currently addressed by the H2020 RenOnBill project, which focuses on these schemes to enhance and support large-scale investments for energy efficiency and deep residential stock renov... [more]

The main objective of this study was to examine the nonlinear relationship between environmental deterioration and foreign direct investment for subpanels based on the country’s income level. In this study, the model’s determinants were total consumption of energy and electricity consumption, the share of renewable energy, and economic growth. Due to the observation of cross-sectional dependence, utilization of cointegration tests and panel data unit root were incorporated, which confirmed a mixed integration order. For the compliance of long-run and short-run relationships among the variables, a pooled mean group estimator panel auto-regressive distributed lag approach was incorporated. The results of long-run development support the pollution haven hypothesis; hence, ecological footprint is increased by the activities related to foreign direct investments. The obtained findings depend on the different subpanels based on the income level of countries. For the assurance of economic dev... [more]

Albania’s electricity sector lacks energy storage systems (ESS); hence, large quantities of electricity generated during the off-peak time, and excess electricity cannot be stored. On the other hand, the transmission capacity upgrades do not keep pace with the growth in peak electric demand; thus, congestion-related issues occur. Congestion of transmission lines has led to considerable uncertainties. Drin River cascade is located north of Albania. It possesses enormous potential energy that is not used due to a lack of ESS. Security of supply, rational use of renewable energy sources (RES), diversification of the electricity sector, increased competitiveness, sheltering more future RES capacities that can benefit from deferring investment in the existing transmission system, and environmental protection are some of these the main benefits of integrating ESS. Regarding the energy transition, the Albanian government’s endeavor aims to maintain and further develop a flexible, sustainable,... [more]

Hydrogen production from surplus solar electricity as energy storage for export purposes can push towards large-scale application of solar energy in the United Arab Emirates and the Middle East region; this region’s properties of high solar irradiance and vast empty lands provide a good fit for solar technologies such as concentrated solar power and photovoltaics. However, a thorough comparison between the two solar technologies, as well as investigating the infrastructure of the United Arab Emirates for a well-to-ship hydrogen pathway, is yet to be fully carried out. Therefore, in this study we aim to provide a full model for solar hydrogen production and delivery by evaluating the potential of concentrated solar power and photovoltaics in the UAE, then comparing two different pathways for hydrogen delivery based on the location of hydrogen production sites. A Solid Oxide Cell Electrolyzer (SOEC) is used for technical comparison, while the shortest routes for hydrogen transport were a... [more]

Understanding solar energy has become crucial for the development of modern societies. For this reason, significant effort has been placed on building models of solar resource assessment. Here, we analyzed satellite imagery and solar radiation data of three years (2012, 2013, and 2014) to build seven predictive models of the solar energy obtained at different altitudes above sea level. The performance of four machine learning algorithms was evaluated using four evaluation metrics, MBE, R2, RMSE, and MAPE. Random Forest showed the best performance in the model with data obtained at altitudes below 800 m.a.s.l. The results achieved by the algorithm were: 4.89, 0.82, 107.25, and 41.08%, respectively. In general, the differences in the results of the machine learning algorithms in the different models were not very significant; however, the results provide evidence showing that the estimation of solar radiation from satellite images anywhere on the planet is feasible.

Legislative efforts for renewables-based energy decarbonisation hinge upon the support and commitment from different stakeholders holding often conflicting positions regarding disruptive processes of socio-technical transformation. However, the evolving acceptance of market actors on the policy-driven promotion of renewables over time remains under-scrutinised. Simultaneously, despite growing attention to power and politics in sustainability transitions, limited efforts remain invested for elucidating the political-economic nature of the market-based selection environments they are operationalised through, highlighting the need for a more systematic comprehension of the “politics of selection”. To address these shortcomings, this paper provides a more refined understanding of the role of policy-driven markets and its participating agents in facilitating/hindering innovation diffusion and broader (system-wide) sustainability transitions. To do so, it showcases a longitudinal case study... [more]

The adoption of green building technology has become significant for ensuring sustainable development; it has become the main step to a sustainable future. The designs for green buildings include finding a balance between comfortable home construction and a sustainable environment. Moreover, the application of emerging technology is also used to supplement existing methods in the development of greener buildings to preserve a sustainable built environment. The main problem of this research is how to tackle the environmental parameters balance based on new techniques that are being used for green building optimization. To mitigate the cumulative effect of the constructed climate on human wellbeing and the regular ecosystem, the most popular goals for green buildings should be planned. This can be achieved by efficient use of natural resources such as energy, water, and other resources and minimizing waste. This will contribute to the security of occupant health, enhancement of work perf... [more]

While the contribution of renewable energy technologies to the energy system is increasing, so is its level of complexity. In addition to new types of consumer systems, the future system will be characterized by volatile generation plants that will require storage technologies. Furthermore, a solid interconnected system that enables the transit of electrical energy can reduce the need for generation and storage systems. Therefore, appropriate methods are needed to analyze energy production and consumption interactions within different system constellations. Energy system models can help to understand and build these future energy systems. However, although various energy models already exist, none of them can cover all issues related to integrating renewable energy systems. The existing research gap is also reflected in the fact that current models cannot model the entire energy system for very high shares of renewable energies with high temporal resolution (15 min or 1-h steps) and hi... [more]