Annual Electricity Production Research Articles

Thermodynamic analysis on a novel bypass steam recovery system for parabolic trough concentrated solar power plants during start-up processes

Most concentrated solar power plants undergo daily start-up and shut-down processes, which consume much energy. If the start-up energy losses can be recovered, the power plant efficiency may be enhanced. The energy loss of bypass steam is one of the major start-up energy losses, but the method to recover bypass steam is absent. Therefore, we proposed a novel system to recover bypass steam by integrating a steam accumulator, and the recovered bypass steam was used to replace the extraction steam of regenerative heaters. The dynamic models of the bypass steam recovery system were developed, and the design parameters and discharging strategy of the steam accumulator were optimized. Results show that simultaneously increasing the initial pressure and volume of the steam accumulator can increase recovered exergy, and switching the regenerative heater received steam during the steam accumulator discharging process can improve electricity production. The optimal initial pressure and volume of the steam accumulator are 2.6 MPa and 246.4 m3, respectively, by balancing the tradeoff between the annual electricity production and the steam accumulator volume. Integrating the steam accumulator with optimal design parameters can improve the annual electricity production by 1.1 GWh (0.55%) for a 50 MW parabolic trough concentrated solar power.

Techno-Environmental Analysis of Facade Integrated Photovoltaics and Electric Vehicle Charging for University Building

Electric vehicles (EV) are a relatively contemporary and emerging technology in the transportation and power sectors, with several economic and environmental advantages. However, there are still challenges associated with EV charging depending on on-grid electricity. University buildings that consume a lot of energy continue to rely on the grid and/or conventional fuel for consumption. In addition, EV Charging will create more challenges in meeting the demand; therefore, utilizing university rooftops for EV charging has high prospects of meeting the additional energy demand. In Malaysia, no such research has been presented that has explored the possibility of using academic institute rooftops for BIPV installation for EV Charging in terms of energy and environmental standpoint. The current study analyzes and evaluates a rooftop grid-connected Building Integrated photovoltaic (BIPV) system for generating electricity and EV charging at the University Malaysia Pahang, Malaysia, for EV charging. The system’s energy output has been simulated using the PVSyst in two scenarios, i.e., fully integrated with no ventilation and free mounted with air circulation. It was found that 7000 m2 of the selected building’s rooftop area could be used for panel installation. The panels’ total capacity was 1.069 MW, with total annual electricity production of 1587 MWh and 1669 MWh in respective scenarios. The proposed BIPV plant would reduce GHG emissions of 60,031 tons of CO2e in scenarios 1 and 61,191 tons of CO2 in scenario 2 compared to the emission produced by coal plants for the same amount of annual energy generation.

Biomass-Based Renewable Energy Community: Economic Analysis of a Real Case Study

Renewable energy communities are catalysts of social innovation, the citizens’ engagement in energy actions, and the exploitation of local resources. Thus, this paper defines a model for analyzing and optimally sizing energy systems serving renewable energy communities. Then, the proposed and replicable model was tailored to the economic feasibility analysis of a renewable energy community in the municipality of Tirano (Northern Italy). An energy audit was carried out to identify the electricity production and consumption within the perimeter of the primary substation and the thermal energy demand of the existing district heating network. The technical features of the energy conversion systems serving the renewable energy community were determined: an organic Rankine cycle biomass-based cogeneration plant, a mini-hydro plant, and a distributed photovoltaic system. Moreover, several different scenarios have been identified, in terms of cogeneration operating mode, photovoltaic penetration, and thermal energy economic value. The results show that, moving from 4.22 MW to 5.22 MW of photovoltaic peak power, the annual renewable electricity production increases by 10.1%. In particular, the simple pay back ranges between 4.90 and 4.98 years and the net present value between EUR 12.4 and 13.3 M for CHP operating at full power mode, considering that thermal energy available from the cogeneration unit is sold at EUR 49.2/MWh. These outcomes demonstrate the economic feasibility of wood-biomass-based renewable energy communities, which may help to enlarge the contribution of renewable technologies other than photovoltaic.

The status of implementation of photovoltaic systems and its influencing factors in European countries

AbstractThis paper gives an overview of the status of implementation of photovoltaic (PV) systems among 34 member countries involved in the COST Action PEARL PV in the year 2018. Besides this, influencing factors that have an impact on the implementation of PV systems in each country have been assessed. The implementation of PV systems varies in European countries due to differences in solar irradiation and weather conditions, electricity consumption, national economic situation, and governmental approaches to promote PV. For this paper, data sets covering, among others, numbers installed PV systems, and the variables mentioned above, were collected, processed, and synchronized. Subsequently, relations between data were analyzed by geographic mapping and mutual correlations. The 34 countries evaluated produced together 120 TWh of PV electricity in 2018. It was notable that Germany produced the highest amount (45 TWh) and has the highest share (8.4%) of PV in its electricity generation. Weak correlations were found between the different variables and the gross domestic product, annual global irradiation, number of subsidy schemes, cumulative installed capacity, annual electricity generated by PV, the share of RE, and share of PV. Logically, as expected, strong correlations (R2 = 0.9) were found between the number of inhabitants and the annual electricity production and consumption. From our analysis, we conclude that four different groups of countries can be identified to categorize the usability of PV. One type covers countries with a significant unused PV potential while local–global irradiation is redundantly available, such as Turkey, Spain, Cyprus, Portugal, and Israel.

Economic and environmental assessment of the implementation of solar chimney plant for water production in two cities in UAE

• Solar chimney power plant (SCPP) system is used to generate electrical power and produce distilled water for different wind speeds in two cities in UAE. • Sharjah and Alain cities in UAE were selected based on the geographic location and metrological data. • Alain city shows more annual electrical power and water production than Sharjah city. • The economic and environmental considerations were evaluated and compared with the reverse osmosis (RO) technique. In this paper, a solar chimney power plant (SCPP) system is modeled and simulated using MATLAB code. The economic and environmental considerations were analyzed for the SCPP. The implementation of the SCPP system in Sharjah and Al Ain cities in the United Arab Emirates (UAE) were compared in terms of electrical power generation and cumulative water production, as well as the potential of increasing the wind speed by 2.5% - 10% with a step of 2.5%. The selected cities were considered due to the big difference in the relative humidity. The results showed that even though Sharjah’s water production was more stable and consistent, Al-Ain would have significantly higher water production and slightly lower power generation. After increasing the wind speed, both cities showed similar behavior of a significant increase in water production and a slight decrease in power generation. The novel design was analyzed and compared to the reverse osmosis technology from an economic and an environmental perspective. Using the SCPP is in alignment with the 2030 vision of the UAE for both electrical power generation and water production. Furthermore, the SCPP can be an effective solution to solve the demand for energy and water and reduce the effect of greenhouse gas (GHG) emissions.

Multi‐objective optimization of annual electricity consumption and annual electricity production of a residential building using photovoltaic shadings

Multi‐objective optimization of annual electricity consumption and annual electricity production of a residential building using photovoltaic shadings

Simulation, sizing, economic evaluation and environmental impact assessment of a photovoltaic power plant for the electrification of an establishment

ABSTRACT In this article we determined the total peak power to be installed, i.e. 220 kWp. In parallel, using the PVSYST software, we redesigned the PV array and we carried out a first simulation of the annual electricity production, a second simulation of the power losses and a third simulation of the saved quantity of CO2 by using the PV array. Based on the PV modules and inverters characteristics available on the local market, the number of inverters and the global investment cost of the installation which amounts to 157929,74 USD. Through these simulations, we were able to determine the annual average value of the performance ratio and the theoretical nominal output of module, which is equal to 83.1%, the energy production which is equal to 404.9 MWh, the percentage of power losses at all components of the PV field which is 16% of the total production as well as the quantity of CO2 saved by the use of this installation which is equal to 6142 tCO2 and finally we were able to calculate the price of the kWh injected into the network which is of the order of 0.034 USD /kWh and the amortization duration which is equal to 4.5 years.

Wind Variation near the Black Sea Coastal Areas Reflected by the ERA5 Dataset

In the context of the European Green Deal implementation, it is expected that there will be an increase in number of the wind farms located near the coastal areas in order to support this initiative. The Black Sea represents an important source of wind energy, and as a consequence, in the present work the regional wind resources (onshore and offshore) are evaluated by considering a total of 20 years of ERA5 wind data covering the 20-year time interval from January 2002 to December 2021. From a general perspective, it is clear that the offshore areas (100 km from the shoreline) are defined by much higher wind speed values than in the onshore, reaching an average of 8.75 m/s for the points located on the western sector. During the winter, these values can go up to 8.75 m/s, with the mention that the northern sectors from Ukraine and Russia may easily exceed 8 m/s. In terms of the wind turbines’ selection, for the offshore areas defined by consistent wind resources, generators will be considered that are defined by a rated wind speed of 11 m/s. Finally, we can mention that a theoretical offshore wind turbine of 20 MW can reach a capacity factor located between 20.9 and 48.3%, while a maximum annual electricity production of 84.6 GWh may be obtained from the sites located near the Romanian and Ukrainian sectors, respectively.

Optimal sizing and techno-economic analysis of a hybrid solar PV/wind/diesel generator system

Hybrid power systems that combine wind and solar PV technology have been widely employed for power generation, particularly for electrification in remote and islanding locations, because they are more cost-effective and reliable than traditional power systems. This article intends to develop an environmentally friendly and cost-effective hybrid power system for selected critical loads in the Avuto community of Ghana. Following the acquisition of site data, a hybrid solar PV, wind, diesel generator, and converter analysis was conducted using HOMER software to establish the appropriate sizing of system components based on technical and economic parameters such as load served, annual electricity production, net present cost (NPC), emission, Operating cost, Fuel consumption and energy cost (COE). Based on the optimization computational results, it can be stated that the combination of system components, including solar photovoltaic, wind turbine, and diesel generator, is a good fit for the application region and might be used for rural and island electrification in the future. The suggested energy system has an LCOE of 0.39 US$/kWh for the 1.08 US$/litre diesel fuel cost and a 3.33-year payback period, with 58.8 kW for PV, 7 units for 3 kW wind turbines, 10 kW for diesel generator, and 6.99 kW for the converter. In terms of emission reduction, the proposed case presented a 55% emission reduction from the base case scenario.

A novel hybrid solar chimney power plant: Performance analysis and deployment feasibility

AbstractThis study presents a novel hybrid solar chimney power plant (HSCPP) design. The HSCPP preserves the typical solar chimney power plant (SCPP), with an additional seawater pool at the base and water sprinklers at the top. This new and novel design configuration offers an opportunity to run the system during the daytime as a traditional SCPP and as a downdraft cooling tower at night. The performance of the HSCPP was analyzed in 16 cities in the Kingdom of Saudi Arabia (KSA) that span the entire geographical area of the country to select the optimal location for installation. The results showed that the highest annual electrical energy production of 676.20 MWh was achieved in the southern city of Shahrurah. However, the lowest annual electrical energy production of 347.59 MWh was found at Wajh, in the west. The highest annual freshwater production was 143,898 tons at Riyadh, in the center. However, the lowest annual freshwater production was 77,868 tons at Muwayh, in the west. Furthermore, the results showed that the proposed HSCPP increased electrical power production by 55% and freshwater production by 20% when compared to traditional SCPP. In addition, an outstanding reduction in CO2 emissions by approximately 56% was associated with such an application of HSCPP. The performance of the HSCPP is very promising, however, the geographical location to install the HSCPP is performance‐critical. Hence, the optimal locations were found to be from the center to the southern part of the KSA.

World Energy Development Trends in the 21st Century

The annual worldwide electricity production for the period from 2010 to 2020 – in total and in the first 22 countries ranked by the annual production in 2020 exceeding 200 billion kWh (TWh) – is analyzed. The share of the leading in the annual worldwide electricity production amounted to 82.3%; therefore, the processes occurring in the energy sector of these countries adequately reflect the processes in the world energy as a whole. The influence of the crisis phenomena in the economies of the countries, as well as the COVID-19 pandemic, on the production of electricity in general and by the types of fuel and energy is revealed. The fact of the largest total capacity commissioned per annum and the amount of electricity production at photovoltaic (PVPP) and wind (WPP) power plants for the entire renewable energy development period is pointed out. At the same time, it is noted that the amount of electricity produced in 2020 worldwide and in the majority of countries was somewhat smaller in comparison with that in 2019. The data on the capacity and production of electricity at photovoltaic and wind power plants in the UES of Russia are given. The amount of RES capacities to be commissioned for the share of renewable energy sources in the total electricity production in Russia to reach 4.5% is estimated.

상업용 건물을 대상으로 한 태양광열-지열 이용 Tri-generation 시스템의 성능분석

It is necessary to introduce renewable energy systems for zero energy building realization. Recently, many individual renewable energy systems are introducing the commercial buildings. However, the individual renewable energy systems have many disadvantages such as imbalance between energy generation and use, and intermittent energy production dependent on weather conditions. To resolve these disadvantages, a Tri-generation system combined with a photovoltaic-thermal (PVT) and ground source heat pump (GSHP) is proposed. The Tri-generation system can overcome the disadvantages of the individual system and stably provide thermal and electrical energy to buildings. Many researchers are conducting a feasibility assessment of the introduction of the Tri-generation system for energy independence in residential buildings, but there are few studies on performance analysis of the Tri-generation system for commercial buildings. In this study, to promote the supply of the Tri-generation system for commercial buildings, performance analysis of the system was conducted through an energy simulation model. The annual thermal and electrical production of the Tri-generation system was analyzed and the coefficient of performance (COP) was compared between the Tri-generation system and the conventional GSHP system. As for the performance analysis results, the COP of the Tri-generation system was up by 50% compared to the conventional GSHP system.

Review and validation of photovoltaic solar simulation tools/software based on case study

Abstract Photovoltaic (PV) systems are an excellent solution to meet energy demand and protect the global environment in many cases. With the increasing utilization of the PV system worldwide, there is an increasing need for simulation tools to predict the PV system’s performance and profitability. This research includes testing and comparison of PV tools: photovoltaic geographical information system (PVGIS), PVWatts, SolarGIS, RETScreen, BlueSol, PVsyst, HelioScope, PV*SOL, Solarius PV, Solar Pro, PV F-Chart, PolySun, solar advisor model (SAM), and hybrid optimization model for electric renewables (HOMER), based on experimental data obtained from fixed on-grid 2 kWp PV system in 2019. The PV system is part of a research project related to the examination of the PV system operation in real climatic conditions in Niš. This research investigates the most appropriate PV software for PV systems design by testing the most commonly used PV tools. It was accomplished by comparing experimental data obtained by a 2 kWp PV system in Niš and estimated data obtained from different PV tools. The study shows that annually, the experimentally measured average daily solar irradiation on the inclined plane was 5,270 Wh/m2/day, and the lowest deviation of the simulation results compared to experimental measurements was obtained by SolarPro. Total annual electricity production from the given system was 2455.621 kW h, and the lowest deviation of the simulation results compared to experimental measurements was obtained by PVGIS. By analyzing and publishing the actual solar irradiation and PV power output data, this study could help researchers to increase the PV systems modeling accuracy.

Energy and Environmental Assessment of a Hybrid Dish-Stirling Concentrating Solar Power Plant

Although the 2019 global pandemic slowed the growing trend of CO2 concentrations in the atmosphere, it has since resumed its rise, prompting world leaders to accelerate the generation of electricity from renewable sources. The study presented in this paper is focused on the evaluation of the energy and environmental benefits corresponding to the hypothesis of hybridizing a dish-Stirling plant installed on the university campus of Palermo (Italy). These analyses were carried out by means of dynamic simulations based on an accurate energy model validated with the experimental data collected during the measurement campaign that occurred during the period of operation of the reference plant. Assuming different scenarios for managing the production period and different fuels, including renewable fuels, it was found that the annual electricity production of the dish-Stirling system operating in solar mode can be increased by between 47% and 78% when hybridized. This would correspond to an increase in generation efficiency ranging from 4% to 16%. Finally, assuming that the dish-Stirling system is hybridized with renewable combustible gases, this would result in avoided CO2 emissions of between approximately 1594 and 3953 tons over the 25-year lifetime of the examined plant.

Blue Energy Spearheading the Energy Transition: The Case of Crete

Decarbonization of remote or isolated island communities represents a significant challenge nowadays. Nevertheless, the environmental, economic, and social benefits seek more attention. Lately, blue energy sources, particularly offshore wind power, are gaining momentum to take the lead in the energy transition process, simultaneously offering numerous benefits for local communities and potential investors. In this research, offshore wind power is considered the main driver of the energy transition for the case of the island of Crete. The energy systems’ development scenarios are developed using an energy planning model EnergyPLAN, starting from a reference model developed for the year 2017. Since the island was recently isolated without connections to the mainland grid, integrating renewable energy sources was a challenging task that led to poor energy potential exploitation. The decarbonization of the power generation sector by offshore and onshore wind and photovoltaics can only partially reduce the import dependence on fossil fuels. At the same time, more significant efforts are expected in the transport and industry sectors. With the operational interconnections, 300 MW of offshore wind capacities can be deployed, averaging annual electricity production of 1.17 TWh, satisfying around 70% of total electricity demand.

Efficiency and sustainability assessment of evaporative cooling of photovoltaics

The cooling of PV has been shown to increase electricity production. Among passive techniques, evaporative cooling has one of the greatest potentials. In this work, the efficiency and sustainability of this technique have been investigated for various climatic conditions. In-situ experiments were conducted to develop parametric models for PV cell temperatures and back surface convective heat transfer coefficient. Experiments have revealed an up to 20.1 °C lower peak PV temperature and up to 9.6% increased electric power. Year-round analysis was made for eight cities to determine the required roof size to capture precipitation and the volume of rainwater storage for sustainable evaporative cooling. The study shows that sustainable PV evaporative cooling is possible in cities with temperate and continental climates, where 1–3 m2 of roof area and 50–150 l of rainwater storage are needed for 1 m2 of PV. The annual electricity production can increase by 5.9–9.4 kWh/m2a, which is a 3.6–4.6% increase. In the semi-arid climate of Lampedusa, a roof above 4 m2 and a storage of up to 500 l per m2 of PV are required. In the desert climate of Almeria and Athens, sustainable evaporative cooling is not feasible.

Using renewable (solar) energy as a sustainable management pathway of lands highly sensitive to degradation in Romania. A countrywide analysis based on exploring the geographical and technical solar potentials

Solar power is a major pillar of renewable energy, but there is a complicated dilemma on harvesting solar energy across extensive lands without affecting their agricultural potential. This dilemma could be addressed by developing solar energy systems in areas highly prone to land degradation, which are less feasible for agricultural crops and consequently preferred locations for solar electricity generation. In this context, the present study aims to investigate, for the first time, the feasibility of solar energy harvesting in lands that are highly sensitive to degradation in Romania, starting from the hypothesis that these lands with poor agro-ecological productivity can be a sustainable pathway for large-scale development of photovoltaic power. In line with this goal, complex and high-resolution data on solar energy and land degradation sensitivity were used, which were processed for modelling the key geographical and technical potentials of solar power. By investigating the solar electricity resources of lands critically exposed to degradation and feasible (without environmental constraints) for solar energy development, it was found that Romania holds a vast photovoltaic power potential, by far theoretically capable of meeting all the country's electrical needs. Quantitatively, the total solar energy potential that can be harvested annually from the critical landscapes reaches 1978 TWh, which is over thirty/forty times more than the annual mean electricity production (∼63 TWh)/consumption (∼47 TWh), recorded nationally in the past decade, from all renewable and non-renewable sources. This entire solar potential stretches across ∼30000 km2 (13% of the country) of lands with high degradative conditions, but which are geographically and ecologically suitable for solar applications. These findings can be useful for strengthening the country's energy security, for a sustainable management of national lands highly exposed to degradation, and for a more efficient implementation of several Sustainable Development Goals in Romania.

Development of an integrated solar and wind driven energy system for desalination and power generation

Energy and water are clearly recognized by people as two primary life-sustaining commodities. In terms of current global environmental initiatives, it is important to provide them both in a nature-friendly manner. This study develops a new renewable-based integrated energy system for power generation and desalination and investigates it specifically for Antigua and Barbuda, a Caribbean island nation, to reduce the region’s reliance on a volatile and polluting fossil fuel-based energy infrastructure. Solar and wind, abundantly available in the region, are considered and utilized as the two energy sources enabling electricity and potable water production in a nature-friendly manner. The excess power generated by photovoltaic solar panels and wind turbine arrays is mechanically stored by compressing air into off-shore underwater balloons to provide a reliable renewable-based energy infrastructure for Antigua and Barbuda. The system’s performance is investigated energetically and exergetically by using thermodynamic approaches. In this regard, it is evaluated that the proposed system is capable of operating with energy and exergy efficiencies of 45.4% and 37.6%, respectively. The system’s annual electricity production is evaluated as 316 GWh corresponding to 102.6% of annual electricity requirement of Antigua and Barbuda. In addition, the system supplies 124 tons of fresh water on a daily-basis and compressed air to fuel 140 short-range (80 km) pneumatic vehicles. It is, furthermore, found that potential system implementation can reduce greenhouse gas emissions in the region by 88%.

Potential application of cascade adsorption-vapor compression refrigeration system powered by photovoltaic/thermal collectors

• Cascade adsorption-compression system is investigated using photovoltaic thermal collectors. • Overall performance enhancement is attained at higher chilled water temperatures. • Annual energy saving proportionally increases with collector numbers up to 29%. • Distinctive payback period is attained compared to the state-of-the-art systems. In the present study, a theoretical assessment of an adsorption-assisted cascade compression refrigeration system powered by photovoltaic/thermal collectors is performed. The proposed system is intended to produce refrigeration and electricity simultaneously. Herein, mathematical modeling of the proposed system is developed using MATLAB/SIMULINK and validated with the open literature. The impact of collector area, compressor displacement volume, cooling water temperature, and brine temperature on the system performance are quantitatively investigated and analyzed. The economic analysis of the proposed system has also been conducted. It is observed that decreasing the compressor displacement volume and cooling water temperature could substantially increase the overall coefficient of performance and energy saving. Furthermore, the results demonstrate that the system performance enhances with the increase of the collector area and the brine temperature. It is found that the proposed system can concurrently attain a daily average cooling capacity and electricity yield of 1.7 kW and 103 kWh at cooling and brine temperatures of 30 °C and −20 °C, respectively. Simulation results indicate that the proposed system can generate annual refrigeration production and electricity production of 34.4 kWh c m −2 and 213 kWh el m −2 , respectively, with an annual average coefficient of performance of 2.38. Moreover, the economic analysis exhibited that the photovoltaic/thermal collectors-assisted cascade adsorption-compression system is economically competitive for refrigeration applications, revealing an annual energy saving of 24.8% and a payback period of ∼3.9 years. In this regard, cascade adsorption-compression systems could significantly extend the potential application and energy savings for cooling systems and heat pumps.

Experimental evaluation of an ORC-CHP architecture based on regenerative preheating for geothermal applications

The Organic Rankine Cycle (ORC) can be applied to generate power from low-temperature heat sources and thus supports a sustainable energy system. This paper contributes to ORC development, particularly for geothermal applications, to increase competitiveness of the technology. To this end, new plant architectures based on regenerative preheating are being investigated. The concept of regenerative preheating is investigated in literature by numerical studies and its thermodynamic and economic performance is predominantly evaluated positively. However, regenerative preheating has not yet been realized in experimental ORC test rigs or commercial products. For this purpose, a novel ORC test rig is designed, constructed and commissioned. For evaluation purposes, the regenerative preheating concept is compared to a standard ORC configuration. As a result, a 9.9% higher net thermal efficiency is achieved with regenerative preheating, while the net power output is equal to the one achieved with the standard configuration. This result is particularly important for combined heat and power (CHP) generation due to the reduced cooling of the heat source. In order to evaluate this concept for CHP applications, a novel ORC-CHP architecture based on regenerative preheating is experimentally compared to three state-of-the-art ORC-CHP concepts. Moreover, three different supply and return temperatures of the district heating system (DHS) are considered. The results reveal that the novel architecture, in combination with low- and medium-temperature DHS, leads to an increased part-load performance and a wider operating range. This enables up to 9.4% increase in annual net electricity production, which accounts for additional revenues of 4.56million € in the case of a typical geothermal project. Thus, it can be concluded that this novel ORC-CHP architecture is beneficial from a technical perspective and also promising in terms of economics.