Electricity Generation Technologies Research Articles

Comparative Life-Cycle Assessment of Electricity-Generation Technologies: West Texas Case Study

This comparison of five power plants in West Texas is intended to provide various decision-makers and stakeholders with a holistic picture of the life-cycle environmental impacts associated with these power plants. A key contribution of this analysis is that we assumed all power plants generate the same amount of electricity over a 30-year life, taking a 500 MW combined-cycle gas turbine (CCGT) plant as a benchmark. Also, in two cases, we added battery storage to wind and solar PV facilities to render them nearly as dispatchable as the CCGT. We included the entire supply chain supporting electricity generation, which encompassed raw material sourcing, processing, manufacturing, operations, and product end of life, also called “cradle to grave”. We report on 18 environmental impacts using ReCiPe midpoint (H) impact assessment. The supply chains are global, and impacts are felt differently by host communities across the world. The results can help stakeholders identify hotspots across numerous supply chains with the highest environmental impacts. We discuss some remedial measures and challenges to inform future analysis by the research community.

Avoiding ecosystem and social impacts of hydropower, wind, and solar in Southern Africa’s low-carbon electricity system

The scale at which low-carbon electricity will need to be deployed to meet economic growth, electrification, and climate goals in Africa is unprecedented, yet the potential land use and freshwater impacts from this massive build-out of energy infrastructure is poorly understood. In this study, we characterize low-impact onshore wind, solar photovoltaics, and hydropower potential in Southern Africa and identify the cost-optimal mix of electricity generation technologies under different sets of socio-environmental land use and freshwater constraints and carbon targets. We find substantial wind and solar potential after applying land use protections, but about 40% of planned or proposed hydropower projects face socio-environmental conflicts. Applying land and freshwater protections results in more wind, solar, and battery capacity and less hydropower capacity compared to scenarios without protections. While a carbon target favors hydropower, the amount of cost-competitively selected hydropower is at most 45% of planned or proposed hydropower capacity in any scenario—and is only 25% under socio-environmental protections. Achieving both carbon targets and socio-environmental protections results in system cost increases of 3-6%. In the absence of land and freshwater protections, environmental and social impacts from new hydropower development could be significant.

Economic Viability of Business models for Photovoltaic solar generation in Brazil: Studies of cases

In the last years, worldwide, more capacity of solar energy has been added than any other type of electric power generation technology. The current expansion market is largely due to the increase in market competitiveness of photovoltaic solar energy and demand for electricity. However, the markets continue to be driven largely by government or regulatory incentives and not by innovative business. Therefore, this paper presents: (i) overview of photovoltaic systems regarding the most adopted business models in Brazil; ii) business model economic viability case study. The results presented shows that the acquisition model has the best investment indicators. For the Acquisition and Rental models, all case studies were economically viable, but in the Shared Solar Generation model the Consumer Units C1 and C2 were considered unfeasible by Levelized Cost of Energy - LCOE criterion.

Selection the optimal technology for electricity generation of 5 MW using a fuzzy multi-criteria decision-making approach

Today's challenges towards a sustainable energy development in most European nations are crucial and highly complicated. We find the need to choose between several technologies generation, whose task is very laborious. Multiple factors that affect the success of a Renewable Energy (RE) project must be analyzed and taken into account. The evaluation and comparison of possible technologies generation is a multi criteria decision problem because not only economic aspects must be considered but also technical, environmental and social aspects. This paper presents the case for selecting the optimal technology for electricity generation of 5 MW for a region located in the southeast of Spain. As most of the real-world multicriteria decision-making (MCDM) problems contain a mixture of quantitative and qualitative criteria; therefore discrete MCDM methods are inadequate for handling this type of decision problems.

Bi6Te2-xRxO13 (R=Ti, Si, Ce) Systems: A Investigation for Fuel Cell Applications

In recent years, the increase of economic and environmental problems related to energy generation has increased researches at renewable energy sources. Among others, the fuel cells excel as promising alternative technology of electricity generation and materials science is an ally in the search for better and more efficient materials for this application. In particular, solid-state ionic conductors represent functional materials with promising advantages for fuel cells, as is the case of Bi2O3-based oxygen ion conductors, however, they need to have its cubic phase stabilized at room temperature. This paper presents a study of the Bi6Te2-xRxO13 (R = Ti, Si and Ce) systems for such an application. Solid state reaction was used to materials synthesis. The 3Bi2O3:2TeO2 system present two phases, an orthorhombic one (Bi6Te2O15) stable at room temperature and another high temperature cubic (Bi6Te2O13). Experiments of substitution of Te ions by Ti, Si and Ce ions using the Bi6Te2- xRxO13 matrix were done intending to stabilize the cubic phase at room temperature and the results are presented as well as discussed here.

Mapping Renewable Energy among Antarctic Research Stations

This paper presents an overview of current electricity generation and consumption patterns in the Antarctic. Based on both previously published and newly collected data, the paper describes the current status of renewable-energy use at research stations in the Antarctic. A more detailed view of electricity systems is also presented, demonstrating how different types of resources may be used and combined. The paper will serve as a guide to various renewable-energy generation technologies, highlighting well-established praxis, lessons learned, and potential ideas for improvement. Several renewable electricity generation technologies that have proven effective for use in the Antarctic environment are described. as well as those that are currently in use. Finally, the paper summarizes the major lessons learned to support future projects and close the knowledge gap. The use of renewable-energy sources has the potential to reduce research stations’ greenhouse gas emissions, making research in Antarctica more sustainable. The availability of high-quality energy is crucial for survival and to allow scientists to conduct meaningful research at research stations under harsh Antarctic conditions.

Assessment of hydropower potential of some existing obstacles on rivers. Case study: Arges-Vedea basin, Romania

Hydropower represents one of the oldest and most developed technologies for electricity generation. Combined with more and more harsh environmental … societal restrictions, this led to a lack of available sites for developing new hydropower plants. At the same time, water streams are usually equipped with different hydrotechnical works for preventing flooding or assuring/supplying water to various beneficiaries. This is why in the latest years there is a new trend related to empowering existing hydrotechnical structures. This paper presents an assessment of the theoretical hydropower potential for 7 existing water barriers in Arges-Vedea hydrographic basin, Romania. Based on historical river discharge data and forecasted data for two climate change scenarios, RCP 4.5 and RCP 8.5, the gain in clean energy is presented and compared with the results for the reference period. The results show that while the cost of empowering the considered sites is around 760,000 Euro, a total energy generation of over 600 MWh/year can be obtained.

Communication on the potential of applied PV in the European Union: Rooftops, reservoirs, roads (R3)

Photovoltaics (PV) is a cost-competitive and scalable technology for electricity generation that plays a crucial role to accelerate the European energy transition and achieve carbon neutrality. Large-scale installation of rooftop PV, as well as innovative PV applications such as floating PV coupled with hydropower and bifacial PV along roads and railways, offer multi-benefits, not least in reducing competition for land. In this study, we present a geospatial approach to assess the pan-European technical potential of these three applications, using publicly available datasets. The findings reveal that the PV total installed capacity could exceed 1 TWp, which is far larger than the total PV capacity for 2030 in the EU Solar Energy Strategy (720 GWp) and would be a significant contribution to the several TWs needed for the overall transition to net-zero by 2050. The evidence presented is a useful starting point for policy-setting at national and regional level, as well as for research and detailed analyses of location specific solutions.

Evaluating Prospective Energy Services Demand for Residential Solar Photovoltaic (RSPV) Generated Electricity in Lagos State, Nigeria

Rapid urbanisation is pulling demand for energy services and emission of greenhouse gases (GHG) resulting in energy deficit, climate change and global warming. The ongoing energy crisis and degenerating climate condition demands urgent transformation of the energy system to renewable based from nonrenewable (fossil) based. To meet the growing demand for energy services and simultaneously mitigate the environmental impact of the energy sector, an accurate estimation of the demand for renewable generated electricity is vital to guide the policy makers in planning adequately for the adoption of renewable fuelled electricity generation technology in urban areas. This study evaluated the electricity demand for residential solar photovoltaic (RSPV) technology by potential household adopters of the technology in the metropolitan area of Lagos state, Nigeria. The study adopted quantitative research design with structured questionnaire to solicit information from the respondents. Three hundred and twenty-six (326) responses from the potential adopters were analysed with model for analysis of demand for energy (MADE II) and Pareto tool. The results show that the energy intensity for refrigeration services is 1.06 kWh/hh/day, entertainment services is 0.84 kWh/hh/day, computing services is 0.97 kWh/hh/day, space cooling services is 7.59 kWh/hh/day, ventilation services is 9.05 kWh/hh/day, lighting services is kWh/hh/day, cooking services 2.77 kWh/hh/day, process heating services is 6.43 kWh/hh/day and water pumping is 1.89 kWh/hh/day. The study concluded that the household energy services demand for electricity is 24.43 kWh/hh/day by the potential RSPV technology adopters and the total demand from the solar module panel of 31.59 kWh/hh/day with prospect for improvement on the energy intensity at the same output of energy services. Furtherance to this, the study recommends government intervention with formulation and implementation of dedicated policies on household appliances efficiency standard and also introduce financial schemes to support the replacement of inefficient household appliances with highly efficient ones. Further studies could include other non-common energy services that were not considered in this study. The study could also be conducted in other regions of Nigeria and also investigate the economic feasibility and behavioural acceptability of RSPV technology for effective planning of the national energy system transformation.

Effect of investment cost on technology preference in a flexible, low-carbon Finnish power system

This paper investigates the effects of varying investment costs in a cost-optimal portfolio of electricity-generating technologies to achieve a low-carbon power system to help mitigate climate emissions in Finland. Several different cost scenarios for nuclear, solar, wind, and battery technologies are constructed, considering both single- and multi-stage investment-strategy pathways, with sector coupling of the power system to the heating sector and hydrogen production. Potential new nuclear investments are assumed small modular reactors capable of flexible operation, and optional additional flexibility measures from heating and hydrogen sectors are considered. The scenarios are simulated with hourly resolution using GenX, an openly available capacity expansion optimization tool. Across a wide range of assumed investment costs, the results demonstrate a clear role for flexible nuclear power as a provider of both a solid base generation and flexibility to enhance integration of intermittent wind to the system. Despite optimistic cost assumptions for solar and batteries, their role is observed to remain marginal in the Finnish setting, likely due to large seasonal variation in the local solar availability.

Performance evaluation of a novel photo-thermal-electric hybrid system

Solar thermal power systems are promising electricity generation technology; however, their thermal efficiency is low due to the installed tilt angles and heat losses of solar collectors. Herein, a novel photo-thermal-electric hybrid system that integrates a tilt angle-independent and efficient evacuated U-tube solar collector with a thermally regenerative electrochemical cycle is theoretically conceptualized to evaluate its effectiveness. By developing a mathematical model, analytical expressions for performance indicators as well as the conditions delivering electricity of the hybrid system are deduced. Regardless of tilt angle, calculations indicate that the power density, energy efficiency and exergy efficiency can reach 82.99 W m−2, 8.30 % and 7.61 %, respectively. The hybrid system is less efficient than common silicon photovoltaic cells but is more efficient than some photovoltaic/thermal systems. Exhaustive parametric studies reveal that decreasing thermally regenerative electrochemical cycle internal resistance, ambient temperature or liquid flow rate in evacuated U-tube solar collector and increasing temperature coefficient or evacuated U-tube solar collector inlet temperature can enhance the hybrid system performance. Gradient-based local sensitivity analyses identify that the internal resistance and temperature coefficient of the electrochemical cycle are, respectively, the most and least sensitive variables. A practical case study predicts the hybrid system performance under local weather conditions.

Performance prediction and regulation of a tubular solid oxide fuel cell and hydrophilic modified tubular still hybrid system for electricity and freshwater cogeneration

Tubular solid oxide fuel cells (TSOFCs) are a promising technology for electricity generation; however, they also generate high-temperature waste heat, leading to reduced efficiency and energy wastage. To address this challenge and unlock the full potential, a novel geometry-matching hybrid system incorporating methane reforming TSOFC and hydrophilic modified tubular still (HMTS) is proposed and modelled. Considering various irreversible losses, vital performance indicators including power output, energy efficiency and exergy efficiency are firstly derived, through which comprehensive thermodynamic performance features of the TSOFC/HMTS hybrid system are predicted. The proposed system design demonstrates a significant advantage by achieving a maximum output power density that is 99.7 % higher and a corresponding energy efficiency that is 57.3 % higher compared to the standalone TSOFC. Extensive parametric analyses reveal that raising the operating temperature or stream/carbon ratio positively enhances the system's performance. Conversely, increasing electrode tortuosity, electrolyte thickness, wind velocity, or tubular shell diameter negatively degrades the system's performance. In addition, the anode thickness is an optimizable parameter. Local sensitivity analyses identify that the operation temperature and electrode tortuosity are, respectively, the most and least sensitive parameters for performance regulation. The findings make a significant step forward in the field of sustainable and innovative energy solutions.

Environmental Impact of Electricity Generation Technologies: A Comparison between Conventional, Nuclear, and Renewable Technologies

The transformation of the energy sector, based on the development of low-carbon technologies, is essential to achieve climate neutrality. The Life Cycle Assessment (LCA) is a powerful methodology for assessing the environmental impact of energy technologies, which proves to be a useful tool for policy makers. The paper is a review of the main LCA studies of power generation systems performed over the past ten years aiming at comparing the energy technologies to identify those with the lowest impact on the environment, evaluated in terms of gCO2eq/kWh emissions. Screening criteria were established to include only studies of the highest qualitative significance. The authors decided to assign greater weight to emission values reported in more recent studies. For nuclear and renewable energy technologies, most of the emissions are related to the pre-operational phases. Notably, both nuclear and wind technologies, along with other renewable sources throughout their entire life cycle, exhibit significantly lower and less variable emissions compared with conventional gas- and coal-fired technologies.

Microalgal cycling in the cathode of microbial fuel cells (MFCs) induced oxygen reduction reaction (ORR) and electricity: A biocatalytic process for clean energy

Development in electricity generation technologies is necessary to ensure a safe and sustainable future. Catalytic activity of oxygen reduction reaction (ORR) is still the key challenge in microbial fuel cells (MFCs) which has not improved significantly even upon the application of catalysts. In this study, microalgae as biocatalysts (i.e., availability of electron acceptors and maintain ORR) were applied for spontaneous bioelectricity generation. Microalgal cycling was performed at various concentrations (5, 10, 15, and 20 % vv−1) in the cathode whereas, 2 % fat, oil, and grease (FOG) were added in the anode. Electrochemical and next-generation sequencing (NGS) analyses along with biological parameters were studied to fully understand the anodic and cathodic behavior towards electrogenesis. Continuous microalgal cycling resulted in the highest power density (21.0 mW m−2) and current density (245 mA m−2) in the reactor loaded with 2 % FOG + 15 % vv−1 microalgae. Electrochemical analysis showed the potential of 2 % FOG + 15 % vv−1 microalgae via exhibiting Ohmic resistance of 34. 9 Ω and charge transfer resistance of 100 Ω with improved ORR activity. NGS revealed that Clostridium (7–16.5 %), Bacteroidetes (4.54–12.87 %), and Geobacter (6.5–22.7 %) were the dominant species involved in the electron transport mechanism. CoA ligase, acetyl-CoA C-acetyltransferase, and acetate kinase were the major enzymes involved in β-oxidation and electrogenesis. This study demonstrated the baseline for the use of microalgae as biocatalyst in cathode of MFCs to improve the catalytic efficiency of ORR.

Технології електрогенерації та теплопостачання для підвищення енергетичної незалежності окремих територіальних громад

Russian attacks on Ukraine's energy system, which led to the blackout of entire cities and the termination of district heating, highlighted the risks and disadvantages of relying on large-scale district energy supply for communities. In this context, it is important to consider the development of the energy supply of communities in the direction of their energy independence. The purpose of the article is to form a list of electricity generation and heat supply technologies for increasing the energy independence of individual territorial communities, which are appropriate for implementation in Ukraine. The article considers the criteria for the analysis and selection of technologies for distributed power generation and heat supply. An analytical overview of the following power generation and heat supply technologies is presented: solar and wind power plants, gas piston and gas turbine plants, generators, batteries, co- and trigeneration plants, biofuel power plants and heat-generating boilers, heat pumps and electric boilers, and their grouping is performed according to the established criteria. All the considered technologies contribute to reducing the external supply of communities with energy resources and reducing losses during the transmission and distribution of electricity. Technologies that use renewable energy sources and local fuels are appropriate for implementation in communities in accordance with the availability of sufficient amounts of resources. Still, in most cases, they are not able to fully provide communities with electrical and thermal energy due to their insufficient quantity and high cost of equipment, such as batteries and heat pumps. Decisions regarding the implementation of a specific technology of distributed generation should be made after a thorough analysis of the conditions and possibilities of the energy supply of each individual community. This article is aimed at discussing the options of increasing energy independence and ensuring the reliability of the energy supply of territorial communities in Ukraine. Keywords: distributed generation, power generation, heat supply, renewable energy sources, cogeneration, biofuels, heat pumps.

A comprehensive analysis of time-dependent performance of a solar chimney power plant equipped with a thermal energy storage system

Solar Chimney Power Plants (SCPP) are among the promising solar thermal electricity generation technologies. Equipped with a Thermal Energy Storage (TES) system, such technologies can overcome variations in the main driving factors such as solar radiation and ambient air temperature. This article presents a comprehensive semi-analytical model of a TES to predict the time-dependent performance of an SCPP. By introducing a Quality Factor of power generation (QF) that includes energy conversion efficiency and capacity factor, the effects of 15 TES materials have been studied on the plant performance. Results indicate no significant difference between water TES and clay or soil type, and water-filled bags or tubes are relatively ineffective in improving performance compared to them. Among the various TES materials analyzed, a type of wet soil, i.e., the specific wet mixture of clay, sand, and silt in closed and dark-colored bags, show excellent performance in both QF enhancement and having low Heat Penetration Depth (HPD) simultaneously. The QF and HPD are directly affected by thermal effusivity and thermal diffusivity, respectively. Implementing wet soil TES for the studied power plant (Manzanares) enhances the QF from 7.46 % (for limestone soil) to 10.95 %. Water-filled bags demonstrate a heat penetration depth of 0.4 m, while wet soil exhibits a slightly greater depth of 0.5 m. Furthermore, water-filled bags experience a broader temperature range of 40 °C, whereas wet soil undergoes a comparatively smaller temperature variation of 26 °C. Furthermore, the capacity factor raises from 41.18 % to 61.07 % when utilizing wet soil TES compared to water-filled bags.

Advancements in Perovskite-Based Cathode Materials for Solid Oxide Fuel Cells: A Comprehensive Review.

The high-temperature solid oxide fuel cells (SOFCs) are the most efficient and green conversion technology for electricity generation from hydrogen-based fuel as compared to conventional thermal power plants. Many efforts have been made to reduce the high operating temperature (>800 °C) to intermediate/low operating temperature (400 °C<T<800 °C) in SOFCs in order to extend their life span, thermal compatibility, cost-effectiveness, and ease of fabrication. However, the major challenges in developing cathode materials for low/intermediate temperature SOFCs include structural stability, catalytic activity for oxygen adsorption and reduction, and tolerance against contaminants such as chromium, boron, and sulfur. This research aims to provide an updated review of the perovskite-based state-of-the-art cathode materials LaSrMnO3 (LSM) and LaSrCOFeO3 (LSCF), as well as the recent trending Ruddlesden-Popper phase (RP) and double perovskite-structured materials SOFCs technology. Our review highlights various strategies such as surface modification, codoping, infiltration/impregnation, and composites with fluorite phases to address the challenges related to LSM/LSCF-based electrode materials and improve their electrocatalytic activity. Moreover, this study also offers insight into the electrochemical performance of the double perovskite oxides and Ruddlesden-Popper phase materials as cathodes for SOFCs.

Integrated life cycle sustainability assessment of the electricity generation sector in Bangladesh: Towards sustainable electricity generation

The electricity sector of Bangladesh has experienced a drastic expansion over the last decade, which will continue in the future. However, the country is not attaining optimal benefit from the sector due to discrepancies among its different components. Increased generation capacity based on fossil fuel sources is not only causing negative environmental impacts but also raising future energy security concerns. Stakeholders are unable to address these interconnected issues due to lack of adequate knowledge, which is leading to policy inconsistencies. This paper aims to evaluate the integrated sustainability of Bangladesh’s electricity generation, considering environmental, economic and social aspects using a life cycle approach. Eighteen sustainability indicators have been assessed for five electricity generation technologies currently in operation. Applying a multi-criteria decision analysis, all the technologies have been ranked considering equal as well as differing preferences for the three aspects. Solar power followed by hydropower is the most sustainable option when all aspects are given equal importance and priority is given to economic and social aspects. However, hydropower becomes the most sustainable option when the environmental aspect is prioritized. Among fossil sources, gas is the best and oil power is found as the least sustainable option in all preferences except the environmental aspect when coal becomes the worst. By identifying the disputes between different indicators, this study demonstrates the variations in the results of the integrated sustainability assessment that can be considered while planning improved energy policies for sustainable future electricity generation.

Analysis and Comparison of the DC-DC converter with soft Computing algorithm

Due to technological discoveries in power generation or other power sources, DC-DC converters have developed more practical uses in electrical generation technologies (especially in DC micro grids). Separate the conversion components and generation of an optimized separate predictive algorithm may be achievable through model parameters. The primary goal of implementing an electronic parts converter for grid connection is to provide an amount of energy statistically and quantitatively satisfactory for the many applications at hand. Load frequency control electronics are divided into transistors, DC-to-DC converts, and rectifier diodes. The adapter from DC - DC is frequently used even among the many. The proposed technique can be applied to other parameter verification and improvement conditions, such as rectifier circuits, filter power supplies, etc.

A numerical approach to the treatment of submerged water exchange processes through the sluice gates of a tidal power plant

Tidal power generation is a sustainable technology for electricity generation and is regulated by water exchange through the hydraulic structures of the tidal power plant (TPP). In the numerical modeling of tidal power generation, the water exchange rate through the sluice gate has previously been estimated based on the water level difference and was input for the entire water column as a two-dimensional boundary condition. However, in this study, a three-dimensional simulation method for the water exchange rate, including submerged hydrological conditions and the momentum of the surrounding flow, was applied. A new numerical approach to water exchange was applied in the idealized tests, and the subsequent model results showed high reproducibility for the orifice velocity field results from laboratory experiments. To verify the hydrodynamics with the actual region, a numerical model was configured for the Sihwa TPP and evaluated through comparison with observation data. The model not only accurately reproduced the temporal variability of the current velocity results, but also reliably reproduced the spatiotemporal flow patterns related to the jet-like and anticlockwise rotating flows. Therefore, to explain the complex, spatiotemporal, and asymmetric flow structure around TPP, high-resolution grid-based 3D modeling technology associated with the submerged sluice gate is needed.