Annual Electricity Production Research Articles

Performance analysis of a hypothetical 1-hectare PV plant in the Benguela region. The first year of operation.

The presents study evaluates the performance of a hypothetical 1-hectare solar photovoltaic (PV) plant located in the Baía Azul Beach, in Benguela, Angola. The first year performance of the plant composed by 2,784 DuoMax 365 PV modules from Trina Solar Company was evaluated by means of the VelaSolaris Polysum software package. The total surface area of the PV modules was of 5,456.64 m2. The annual alternate current electricity production was of 1,511.70 MWh allowing a total of 710.47 tCO2 of CO2 emissions reduction and a performance ratio of 72.8 %. The annual average energy and exergy efficiencies of the PV system were respectively of of 14.3 % and 14.7 %.

Subsidy analysis and development trend forecast of China's unconventional natural gas under the new unconventional gas subsidy policy

In June 2019, China significantly changed its unconventional natural gas subsidy policy, changing the subsidy mode from a comprehensive quota standard mode to a competitive mode, aiming to reduce its subsidy pressure and channel subsidies to specific projects that are needed to increase annual and winter electricity production. Through a brief introduction of China's cleaner energy goals and a comparative analysis of the new and old subsidy policies, the orientations and impacts of the new policy are interpreted. By comparing the changes in subsidy quota, production and price of three kinds of unconventional natural gas (shale gas, tight gas and CBM) over the past ten years, in combination with the generalized Weng model, the impact of subsidy on unconventional natural gas production is quantified. The development trend of unconventional natural gas under the new policy is forecasted on the premise that the total amount of subsidy and sales price remain unchanged.. The sensitivity of three kinds of unconventional natural gas to different subsidies is analyzed. The impact of the new policy on the change in gas production curve is illustrated after comparing the optimal production plans for typical shale gas wells under the new and old policies. The results show that shale gas and CBM may be negatively affected, while the development of tight gas may be promoted; in the future, tight gas and shale gas will dominate, while the development of CBM will be tough. The new policy will stimulate the production enterprises to adopt the plan of high initial production and high decline rate, which may lead to a reduction in total gas production and resources utilization efficiency.

НОРМАТИВНО-ПРАВОВІ АСПЕКТИ ВИКОРИСТАННЯ В УКРАЇНІ ГІДРОЕНЕРГЕТИЧНОГО ПОТЕНЦІАЛУ ЗВОРОТНИХ ВОД ТЕХНОЛОГІЧНИХ ПРОЦЕСІВ ЗА «ЗЕЛЕНИМ» ТАРИФОМ НА ГЕНЕРОВАНУ ЕЛЕКТРОЕНЕРГІЮ

Гідроенергетичний потенціал малих річок України, з урахуванням природоохоронних обмежень на використання води стоку річки для виробництва електроенергії та використання територій для спорудження малих ГЕС, сягає рівня 375 МВт з річним обсягом виробництва електроенергії близько 1270 млн кВт·год/рік. Існують додаткові можливості збільшення потенціалу малої гідроенергетики в результаті використання скидного потенціалу зворотних вод технологічних процесів (водопостачання питної води, водовідведення, зворотні води гірничо-збагачувальних комбінатів, очисних споруд міст та підприємств). При цьому генерування електроенергії здійснюється за відсутності негативного впливу на флору і фауну, оскільки у зворотних водах відсутня риба, річкові тварини, рідкісні птахи, немає потреби в побудові греблі, нового водосховища, не затоплюються навколишні території. Будівництво малих ГЕС на введених в дію спорудах водопостачання та водовідведення сприяє модернізації існуючого об’єкта (ремонт або заміна окремих елементів) та підвищенню його надійності в результаті встановлення сучасної автоматизованої системи управління та моніторингу. Але в переважній більшості випадків, за винятком водопостачання питної води, зворотні води містять значну кількість домішок і хімічних сполук, що значно збільшує питомі витрати на обладнання. Експлуатація обладнання в агресивному середовищі зменшує рентабельність цих проєктів. Тому отримання «зеленого» тарифу на вироблену електроенергію такими малими ГЕС слугує майже єдиною мотивацією для приватних інвесторів. Проте в чинних нормативно-правових актах відсутнє однозначне трактування умов установлення «зеленого» тарифу для ГЕС на зворотних водах. У статті визначено нормативно-правові аспекти для встановлення «зеленого» тарифу на генеровану електроенергію при використанні гідроенергетичного потенціалу зворотних вод технологічних процесів. Наведено короткий опис реалізованого пілотного проєкту малої ГЕС на стічних водах міських очисних споруд на території України, для якої встановлено «зелений» тариф на вироблену електроенергію. Бібл. 17, табл. 2, рис. 1.

Techno-economic viability of on grid micro-hybrid PV/wind/Gen system for an educational building in Iran

In this research, a highly potential campus site for solar/wind energy production is identified with the purpose of micro-hybrid system installation in on-grid mode to sellback the excess electricity and hence economize the building as a source of income. A PV/wind/grid and PV/wind/grid/gen system are surveyed techno-economic wise. For case1, the net present cost (NPC) equals to $49,022, renewable fraction (RF) of 85.5%, and cost of energy (COE) $0.0024 is achieved at an inflation rate of 10% and wind speed of 6.8 m/s. While for the best feasible design of case2 (case2d), the NPC = $224,430, COE = $0.0272, RF = 63.6% are obtained. The results indicated that for a low inflation rate a simple PV/grid is appropriate and with the increase of inflation, more equipment incorporation to the system is a preferable choice. Increasing the number of wind turbine cause NPC reduction and the wind speed increase leads to COE reduction. The results indicated that the case1 with 10 XL10R and 76.0 kW generator capacity could generate 315000 kWh electricity which means 69.2% expenditure decline compared to when one turbine is used (maximum annual electricity production and minimum NPC). Increment of inflation rate from 10% to 15% at $0.35 biodiesel price, increases the RF from 14% to about 50%. This implies that when the fuel price is low together with the high inflation rate, the renewability of the system is more significant.

Plant siting and economic potential of ocean thermal energy conversion in Indonesia a novel GIS-based methodology

Indonesia strives for a renewable energy share of 23% by 2025. One option to contribute to this goal is Ocean Thermal Energy Conversion (OTEC). Despite a global theoretical potential of up to 30 TW, its economically deployable share remains unknown. This paper proposes a novel methodology, which enables to determine OTEC’s economic potential for any regional scope considering technical, economic and natural variables. The methodology was tested for 100 MWe OTEC in Indonesia on a provincial and national level. Against a regionally variable electricity tariff of 6.67–18.14 US$ct.(2018)/kWh, the national economic potential is 0–2 GWe with a Levelized Cost of Electricity (LCOE) as low as 15.6 US$ct.(2018)/kWh. With an annual electricity production of 0–16 TWh, OTEC could provide up to 6% of Indonesia’s electricity demand in 2018. The capacity factor, capital expenses and discount rate are the most sensitive variables of the LCOE on average. A nationally uniform feed-in tariff of 18 US$ct.(2018)/kWh or more could increase the economic potential significantly. The proposed methodology can be a helpful quick-scan tool for determining economically interesting OTEC sites for follow-up in-depth feasibility studies. Limitations are discussed and future research, amongst others upscaling scenarios with cost reducing effects like technological learning, is recommended.

Feasibility Study of a Small-Scale Grid-Connected PV Power Plants in Egypt; Case Study: New Valley Governorate

The construction of photovoltaic power plants (PVPPs) in the right place is an important task when planning the development of the power system and choosing investors. In this paper, the technical, environmental, the economic feasibility of installing a 50kW solar power plant in different places in the New Valley Governorate in Egypt has been presented using RETScreen Expert software. The input data used in the current study are obtained from the database of the Surface Meteorology and Solar Energy Dataset of NASA. In general, five sites for the construction of 50 kW power stations were assessed which represent the five administrative regions of the New Vally governorate. The study is based on annual electricity production, greenhouse gas (GHG) emissions, and financial analysis. With the proposed PV power plant, up to 100 MWh of electricity can be produced and a minimum of 43.3 tons of GHG emission can be prevented from the exhaust into the local atmosphere annually The obtained results from the RETScreen program proved the viability of installing the proposed 50kW photovoltaic power plant in any of the proposed locations. This study could give a piece of important information and feedback that can be utilized as a database for upcoming investments in the photovoltaic generation projects in Egypt.

Impact of the Minimum Head on Low-Head Hydropower Plants Energy Production and Profitability

In Poland, existing barrages are characterized by relatively high flow and low head, which is challenging for the effective utilization of theoretical watercourse power. The paper presents the impact of the minimum head of the hydro sets on the annual electricity production of small hydropower plants at low-head locations for two types of water turbines: Archimedes and Kaplan turbines. A developed mathematical model was used to simulate energy yield from Archimedes and Kaplan turbines for a given value of the minimum technical head, depending on the number of installed hydro sets. For economic analysis purposes, the levelized cost of electricity (LCOE) and net present value (NPV) indicators were calculated. The conducted research allowed for comparing Archimedes and Kaplan’s turbine operating conditions and how the minimum head parameter influences their electricity production and utilization time. As concluded in the results, the influence of minimum head in energy production is more distinct for the Archimedes screw technology than for the Kaplan turbine. The research shows that the decrease in energy production associated with the hydro unit’s minimum head parameter is from 0% to 30% for Kaplan, and it is 6% to 52% for Archimedes turbines.

Techno-economic assessment of performance-enhanced parabolic trough receiver in concentrated solar power plants

Solar-to-thermal conversion efficiency of the parabolic trough collector significantly degrades at high operating temperatures, which exerts seriously negative effects on the development of parabolic trough collectors. To solve this knotty problem, based on the theory of the negative thermal-flux region, a novel parabolic trough solar receiver with a radiation shield was proposed, manufactured, and tested. In this framework, the proposed solar receiver is employed in the concentrated solar power plants using solar salt as the heat transfer fluid to analyze its feasibility in real solar power plants. In this study, the mathematical models of heat collection and economic assessment are established, and the simulation results yield a good agreement with the experimental data. The techno-economic performances of the solar power plants installing the proposed solar receivers in three typical areas under different installed capacities and thermal storage capacities are comprehensively investigated. The results demonstrate that the proposed solar receiver has a great potential for significant enhancement of the techno-economic performance of the solar power plant. The solar power plant with the proposed solar receivers located in Dunhuang can effectively improve the annual net electrical energy production by 9.77%, reduce the levelized cost of energy by 8.67%.

Wind Resource Assessment and Economic Viability of Conventional and Unconventional Small Wind Turbines: A Case Study of Maryland

Annual mean wind speed distribution models for power generation based on regional wind resource maps are limited by spatial and temporal resolutions. These models, in general, do not consider the impact of local terrain and atmospheric circulations. In this study, long-term five-year wind data at three sites on the North, East, and West of the Baltimore metropolitan area, Maryland, USA are statistically analyzed. The Weibull probability density function was defined based on the observatory data. Despite seasonal and spatial variability in the wind resource, the annual mean wind speed for all sites is around 3 m/s, suggesting the region is not suitable for large-scale power generation. However, it does display a wind power capacity that might allow for non-grid connected small-scale wind turbine applications. Technical and economic performance evaluations of more than 150 conventional small-scale wind turbines showed that an annual capacity factor and electricity production of 11% and 1990 kWh, respectively, are achievable. It results in a payback period of 13 years. Government incentives can improve the economic feasibility and attractiveness of investments in small wind turbines. To reduce the payback period lower than 10 years, modern/unconventional wind harvesting technologies are found to be an appealing option in this region. Key contributions of this work are (1) highlighting the need for studying the urban physics rather than just the regional wind resource maps for wind development projects in the build-environment, (2) illustrating the implementation of this approach in a real case study of Maryland, and (3) utilizing techno-economic data to determine suitable wind harnessing solutions for the studied sites.

Techno-economic investigation of electricity and hydrogen production from wind energy in Casablanca, Morocco

The aim of this study is to investigate the technical and economic potential of electricity and hydrogen production in Casablanca, Morocco. For this reason, we simulated the performance of a 4.2 MWp wind turbine if installed in Casablanca. The results show that the electricity and hydrogen production varies greatly through the year due to the high fluctuation in wind speed. The annual electricity and hydrogen production is 29.16 GWh and 555 Tons respectively. As for the levelized cost of production, the LCOE was found to be 0.24 $/kWh and the LCOH2 were equal to 13.52 $/Kg.

Hydrogen Production from Two Commercial Dish/Stirling Systems Compared to the Photovoltaic System-Case Study: Eastern Morocco

In the present work, a comparative analysis of electricity and hydrogen production using concentrated solar power (CSP) and photovoltaic (PV) is carried out. For this purpose, an identical capacity is taken equal to 25 and 10 kWe for both CSP and PV systems have been considered. One-year of metrological data was taken via a high precision weather station consisting of a Kipp and Zonen (K&Z) SOLYS 2 installed in Oujda. The System Advisor Model (SAM) software, version 2018 from NREL laboratory is used for electricity production, and then the hydrogen production has been calculated. The results show that both commercial dish/stirling systems produce more electricity than PV with an annual production of 42.9 MW h instead of 38.4 MW h for PV system with a capacity 25 kWe. Furthermore, the annual hydrogen production from the SES system is 13.6% higher than the PV. Considering the capacity equal to 10 kWe, the WGA dish/stirling system gives an annual electricity production equal to 15.89 MW h instead of 14.07 MW h for the PV system. The annual hydrogen production is around 302.2 kg, while about 267.8 kg is for PV system (10 kWe).

Efficiency increase analysis of large RFPV power plants using reflectors between PV rows

The concept of floating photovoltaic (FPV) power plants that are recognized as an alternative solution for PV power plants installed on land has been developed recently. The dominant reason for this is the fact that FPV power plants occupy inactive surfaces, which is specifically significant in the case of large power plants. Additionally, a promising concept of rotating floating photovoltaic power (RFPV) plants which brings significant improvements in production has been analyzed in literature. Conversely, reflectors were used in many studies for increasing the production of PV panels installed on land. This paper proposes the improvement of large RFPV power plants by using aluminum reflectors. The conceptual solution presented in this paper, which is based on perennial meteorological data, indicates that the proposed solution enables the increase in the annual electricity production of up to 25% in comparison with classical solutions for RFPV power plants. Also, an economic analysis, which takes into account additional financial investments for reflectors, was carried out. The obtained results have shown that the proposed concept of an RFPV is cost-effective.

Wind Resources Assessment and Development of Grid Connected Wind Farm—A Case Study

In the present study, the case study of micro-siting for the campus of the Institute of Nuclear Energy Research (INER) is conducted. Results from the effect of weather data suggest that for the wind turbine system higher than 20 m, the effect of nearby building and wake on electricity production would be less important. The effect of different weather data on the generated annual electricity production (AEP) is consistent for the wind turbine higher than 20 m. The difference between the calculated and real AEP of INER-150 kW wind turbine is only 1.1%, which is much better than some previous studies. The good agreement is mainly due to the higher height of the INER-150 kW (50 m), more stable coming wind and smaller impact of building on the performance of power production. Considering the proactivity on the installation for the site in INER campus, the finalized decision on the selection of wind turbine is 1 kW system. The power generation-related data are collected and processed for the fine tuning of model parameters in the future.

Resource potential for wind-hydrogen power in Ukraine

The paper provides an assessment of the current wind energy potential in Ukraine, and discusses developmental prospects for wind-hydrogen power generation in the country. Hydrogen utilization is a highly promising option for Ukraine's energy system, environment, and business. In Ukraine, an optimal way towards clean zero-carbon energy production is through the development of the wind-hydrogen sector. In order to make it possible, the energy potential of industrial hydrogen production and use has to be studied thoroughly.Ukraine possesses huge resources for wind energy supply. At the beginning of 2020, the total installed capacity of Ukrainian wind farms was 1.17 GW. Wind power generation in Ukraine has significant advantages in comparison to the use of traditional sources such as thermal and nuclear energy.In this work, an assessment of the wind resource potential in Ukraine is made via the geographical approach suggested by the authors, and according to the «Methodical guidelines for the assessment of average annual power generation by a wind turbine based on the long-term wind speed observation data». The paper analyses the long-term dynamics of average annual wind speed at 40 Ukrainian weather stations that provide valid data. The parameter for the vertical wind profile model is calculated based on the data reanalysis for 10 m and 50 m altitudes. The capacity factor (CF) for modern wind turbine generators is determined. The CF spatial distribution for an average 3 MW wind turbine and the power generation potential for the wind power plants across the territory of Ukraine are mapped.Based on the wind energy potential assessment, the equivalent possible production of water electrolysis-derived green hydrogen is estimated. The potential average annual production of green hydrogen across the territory of Ukraine is mapped.It is concluded that Ukraine can potentially establish wind power plants with a total capacity of 688 GW on its territory. The average annual electricity production of this system is supposed to reach up to 2174 bln kWh. Thus, it can provide an average annual production of 483 billion Nm3 (43 million tons) of green hydrogen by electrolysis. The social efficiency of investments in wind-hydrogen electricity is presented.

Potential analysis of roof-mounted solar photovoltaics in Sweden

Solar photovoltaic energy, driven mostly by the residential and commercial market segments, has been growing a lot in recent years in Sweden. In response to the commitment towards sustainability goals, this paper explores the potential of roof-mounted solar photovoltaic projects. This paper focuses on: roof area estimation, potential installed capacity, and potential electricity generation, at the single municipal scale and at the national scale. The following categories of different building types have been investigated: residential buildings, industrial buildings, buildings of social function, buildings of business function, buildings of economic/agricultural function, buildings of complementary function, and buildings of other unknown functions. The analysis starts from Västerås, a typical Swedish municipality and ranking seventh among the largest cities in Sweden. An estimate of 5.74 km2 available roof area potential is calculated, by considering factors such as building purposes, roof orientations, shadows and obstacles. The total potential installed capacity is calculated, assuming the installation of commercial photovoltaic modules, and design parameters for flat roofs such as inter-row distances and tilt angles. With the inputs of meteorological parameters and geographical information, the potential yearly electricity generation is calculated. The results reveal 727, 848, and 956 MWp potential installed capacity and 626, 720, and 801 GWh annual electricity production for Västerås on pitched roofs and flat roofs with three scenarios, respectively. The extrapolation of the methodology to the entire of Sweden yields a total of 504 km2 usable roof area and 65, 75, and 84 GWp installed capacity. Finally, we reveal a new understanding of usable roof area distribution and of potential installed capacity of roof-mounted solar photovoltaic systems, which can largely help evaluate subsidy scale and solar energy policy formulation in Sweden.

Evaluation of the annual electricity production of a hybrid breakwater-integrated wave energy converter

Ocean waves constitute an abundant source of clean and predictable energy, with the potential to partly replace carbon intensive energy sources. At present, several technologies to convert wave energy into electricity are being developed, but those suitable for integration into port breakwaters present additional advantages. This paper presents a novel concept that combines two well-known wave energy conversion principles, an oscillating water column and a multi-reservoir overtopping system. This hybrid concept was designed to be integrated in rubble-mound breakwaters, having as case study Leixões’ northern breakwater, Portugal. The performance and efficiency of the single components were assessed separately as well as that of the hybrid module as a whole, to demonstrate the advantages of their combination into a single unit. Furthermore, the annual energy production was estimated for a 20 m wide hybrid module considering the local metocean conditions. Results showed that overall efficiency amounted to circa 44.4%, the wave-to-wire efficiency to 27.3% and the annual electricity production was estimated at 35 MWh/m. Considering that 240 m of the reference breakwater are used, the developed hybrid module could provide approximately 50% of the electricity consumption of the Port of Leixões, which demonstrates the potential and interest of the developed technology.

A Definitive Model of a Small-Scale Concentrated Solar Power Hybrid Plant Using Air as Heat Transfer Fluid with a Thermal Storage Section and ORC Plants for Energy Recovery

The aim of this work was to propose a small-scale Concentrated Solar Power plant using conventional technologies, in order to improve their flexibility and performances, and reinforce their competitiveness compared to traditional systems. Additionally, this study analyzed the possibility of providing continuity of energy production through an optimized hybrid system, which considered thermal energy storage from a gaseous Heat Transfer Fluid, air. It also considered the possibility of recovering part of the energy of the thermodynamic cycle through an Organic Rankine Cycle system with appropriate dimensions. The final outcomes were a 170 kW CSP plant with about 805 MWh of annual electricity production with a global solar capacity of 32.5%, about 900 kWh of thermal storage daily capacity, and an ORC recovery section of 54.2 kW with a specific production of 260 MWh/y.

Simultaneous design and off-design operation optimization of a waste heat-driven organic Rankine cycle using a multi-period mathematical programming method

The organic Rankine cycle (ORC) has been regarded as one of the most potential technologies for converting low-grade heat into power. In the past decades, the design and operation optimization of ORC has undergone investigation, and most approaches use a sequential or step-by-step approach by separating the off-design operation from the system design and typically lose solution optimality. The current study proposes a simultaneous optimization of the design and off-design operation for a waste heat-driven ORC. The detailed component configuration models for the heat exchangers are developed. A multi-period optimization model is developed to synchronously obtain the configurations of components and scheme of off-design operation that minimizes the annual average electricity production cost. A case study validates the superiority of the proposed multi-period optimization method over a two-step optimization. The ORC obtained using multi-period simultaneous optimization method features 5.7%–16.6% lower average electricity production cost than those achieved with the conventional two-step method.

Sizing of a solar-wind hybrid electric vehicle charging station by using HOMER software

Although, fossil fuels are still the main source that used to balance the global demand/supply dynamics of energy; most countries have embarked on a quest to reach a solution and started changing their direction from fossil resources (especially oil and gas) to other resources by creating new opportunities with a focus meeting the increasing energy demand by reducing it via energy efficiency. “Transportation” is one of the biggest items of global energy consumption with 24% usage percentage and most of this amount is supplied by conventional energy resources. However, worldwide supporting policies and regulations are positively affected the starting period of environment-friendly use of energy resources. It expedited the process of new technological developments that minimize waste, lower the level of air pollution caused by fossil fuel-powered internal combustion engines, conserve forests and decrease the emissions of greenhouse gases. Worldwide extension of “Electric Vehicle Development and Production” is one of the main concern of these regulations. However, increasing the number of electric vehicles also brings sustainability problems such as; supplying the electricity from renewable resources in an efficient and sustainable way, handling the electricity load on the grid, and establishment of new charging stations. Therefore, in this study a wind solar hybrid energy charging station designed and optimized via HOMER software. The sizing methodology is suitable to apply anywhere around the worldwide. The optimal solution for the hybrid system consists of 44.4% wind energy and 55.6% solar energy and the annual electricity production is 843150 kWh with the 0.064 $/kWh production cost.

Implementation of Offshore Wind Turbines to Reduce Air Pollution in Coastal Areas—Case Study Constanta Harbour in the Black Sea

Considering the current concerns regarding the level of air pollution from the Black Sea area, the aim of the present work is to establish whether a cold ironing project that involves the use of the wind resources from the port of Constanta (Romania) could become a reality. The regional and local wind resources measured at a height of 100 m above sea level were assessed by taking into account 20 years (2000–2019) of ERA5 wind data. The wind speed significantly increases as we move towards the offshore areas, with the wind Class C7 reporting a maximum of 41%. By combining the annual electricity production with the emissions associated with the port activities, it was possible to show that at least 385 turbines (each rated at eight MW) will be required to cover the electricity demand for this port. The present study has found it difficult to implement such a project based only on the available wind resources and has identified that more likely a mixed project that involves some other resources will be more appropriate. Finally, it is worth mentioning that the future of the ship industry is becoming greener and definitely, a wind project located near Constanta harbour will represent a viable solution in this direction.