Solar Cogeneration System Research Articles

Techno-economic viability of sustainable solar co-generation using CPV cells in parabolic dish concentrators: A 20-year perspective

Solar co-generation is a cutting-edge technology that enables the instantaneous production of electricity and heat energy by employing concentrated solar power (CSP) systems. This study presents the development and experimental analysis of a novel small-scale solar co-generation system, utilizing concentrated photovoltaic (CPV) cells integrated into a solar paraboloidal dish concentrator (SPDC) for simultaneous electricity and heat production. The system, designed with a high concentration ratio, employs a CPV module composed of four 1 cm × 1 cm cells mounted on a flat receiver of a parabolic dish concentrator with an aperture area of 12.6 m2. Experimental results, obtained over three consecutive days, demonstrate that the CPV module achieves an electric power output ranging from 480 to 645 W daily, while the SPDC system generates thermal energy between 395 and 725 W. The economic analysis indicates a cost of ₹10.75 per unit of electricity, with a payback period of approximately 13.5 years, assuming a 20-year system lifespan. Additionally, the reliability of the CPV module and the impact of varying encapsulation materials were critically assessed, providing insights into potential improvements and long-term performance. The findings underscore the viability and economic potential of solar co-generation systems employing CPV technology, contributing to the advancement of sustainable energy solutions.

Optimizing solar photovoltaic farm-based cogeneration systems with artificial intelligence (AI) and Cascade compressed air energy storage for stable power generation and peak shaving: A Japan-focused case study

This study proposes a novel solar cogeneration system that integrates compressed air energy storage units (CAES) and gas turbines (GT) with a solar farm consisting of photovoltaic panels. The primary objective of this research is to address the instability of solar energy production and help during peak energy consumption by utilizing CAES. The proposed system is modeled using EES software, and its performance is optimized using advanced artificial intelligence (AI) methods, including artificial neural networks and intelligent algorithms. The analysis identifies five critical decision variables that significantly impact system performance: the number of photovoltaic panels, CAES pressure ratio, CAES inlet pressure, gas turbine efficiency, and compressor efficiency. The results demonstrate that the optimized solar cogeneration system can achieve exergy efficiency of 36.44 % and a cost rate of 13.76 $/hour. The exergy analysis of the system indicates that the most significant destruction is related to the solar farm, gas turbine, and compressors. Furthermore, this study investigates the effect of weather in eight Japanese cities on system performance, considering two operating modes: with and without using system electricity (PV mode). The results show that the proposed solar cogeneration system has significant potential for clean electricity generation and CAES applications to overcome the instability of the solar system and help during peak energy consumption throughout the year. The study's findings highlight the attractive potential of integrating CAES and AI technologies in solar photovoltaic systems for stable and efficient power generation in Japan.

6E analysis and particle swarm optimization of a novel ultra-high temperature solar cogeneration system fusing thermochemical energy storage and multistage direct heat transfer

The reshaping of the energy development model depends on the penetration of renewable energy on the input side and the substitution of electrical energy on the supply side. Therefore, this research proposes a novel solar cogeneration system in which the Brayton cycle possesses triple pressure and can be flexibly coupled directly to each subsystem under supercriticality without intermediate exchangers. Firstly, a series of research tasks are executed sequentially, including model establishment, cycle potential comparison, operating parameter analysis, and multi-objective particle swarm optimization. Secondly, the exergy flow rate, consumption rate, and 6E (energy, exergy, exergoeconomic, exergoenvironmental, emergoeconomic, and emergoenvironmental) performances of each subsystem and subcomponent are thoroughly discussed. Lastly, the operating performance, economic benefits, and regional characteristics of each subsystem and the cogeneration system are explored. After optimization, the exergy efficiency, average advanced exergy-emergy factor, and advanced exergy-emergy impact difference of the system are 22.72 %, 56.17 %, and 23.97 %. Compared with similar research, the energy efficiency of the system is improved by 8.2 %, which can repay the capital cost in 8.83 years, and the economic benefit reaches $5,503,086 for the entire service year. The system embodies excellent 6E performance, aligns with the goals of reshaping the energy development model, and provides guidelines for the development of ultra-high temperature solar cogeneration.

A hybrid solar-driven vacuum thermionic generator and looped multi-stage thermoacoustically driven cryocooler system: Exergy- and emergy-based analysis and optimization

Significant high-quality heat is wasted in the vacuum thermionic generator (VTIG), which can be efficiently utilized as a prime mover of a bottoming system for cogeneration applications. For this purpose, a new environmental-friendly hybrid system composed of a heliostat solar field, VTIG, and looped multi-stage thermoacoustically driven cryocooler (LMTC) is established, in which the high-temperature heat source of the solar receiver runs the VTIG to generate power, and the LMTC recovers the waste heat of the VTIG to produce a cooling load. Thermodynamic, economic, and environmental analyses of the system are carried out based on exergy and emergy concepts. Moreover, a parametric study is performed to assess the effect of design parameters on the system's thermodynamic, economic, and environmental criteria. Finally, the multi-criteria salp swarm optimization algorithm and decision-making procedures are conducted to improve the exergetic performance and decrease the system's cost and monetary emergy rates along with the environmental impact and ecological emergy rate. Findings depict that at the reliable, optimal operation of the system, the exergetic efficiency can reach 29.36% with a maximum power of 17.2 MW and cooling load of 0.260 MW. The system's cost and monetary emergy rate can be reduced to 0.059 $/s and 5.94 × 1010 seJ/s, with 10.6% and 10% reductions, respectively. Moreover, the environmental impact and ecological emergy rates decline by 6% and 7.4%, respectively. The theoretical findings may offer guidance for the optimum designing and practical running of such a solar solid-state cogeneration system.

4E analysis and tri-objective optimization of a novel solar 4th cogeneration system for a smart residential building in various climates of Iran

Cogeneration systems are increasingly used in residential buildings due to their high efficiency, low cost, and compatibility with the grid. This investigation proposes a dynamic simulation of a novel intelligent building-integrated solar cogeneration system using TRNSYS software to provide the power demand of system equipment and the required electricity, heating, cooling, and freshwater of a typical residential building in Iran. This system is equipped with photovoltaic panels, evacuated tube collectors, a double-effect absorption chiller, a reverse osmosis water desalination unit, and a micro-gas turbine as a backup system. Using season-temperature sensors and differential controllers helps monitor and handle the energy rates in different parts of the system and building by comparing the outside temperature and relative humidity with comfort conditions in an intelligent method. The system performance is assessed and compared from energy, exergy, exergy-economic, and environmental impact points of view in four cities that cover Iran’s climate variety. EES software is employed to transfer the thermodynamic properties of air and water to the model in TRNSYS. Furthermore, the tri-objective optimization is conducted with a novel procedure through a combination of a machine learning method and genetic algorithm in MATLAB by considering the exergy efficiency, unit product cost, and CO2 emission as objective functions to find the best point of the system and present a 3D Pareto-Frontier. The results show that the system can satisfy all the building energy demands, and on average, the hourly cooling and heating energy production during a year in this system are 1.01 kWh and 1.37 kWh, respectively. Also, the excess produced power is sold to the grid to compensate for some of the system overheads. The tri-objective optimization upshot shows that the values of exergy efficiency, CO2 emission, and unit product cost of this system at the best point are 44.9%, 0.158 ton/MWh, and 12.26 €/MWh, respectively, in Tehran province. Based on the results, the system performance indexes are improved compared to similar technologies found in the literature.

Dynamic price optimization of a solar integrated cogeneration system considering uncertainties of building demands

Introducing renewable and high-efficiency devices into conventional cogeneration systems has the potentials to reduce fossil fuel consumption and mitigate environmental issues. This study aims to incorporate solar power and thermal energy into the power and waste heat generated by the gas turbine, respectively, while utilizing a double-effect absorption heat pump to meet the total heat demands. Following the creation of thermodynamic models, a trading mechanism is introduced involving an operating participant known as the product seller, which is analogous to electricity companies in power trading models. To maximize the interests of the participants with different confidence levels, the master-slave game is employed, using Genetic and Quadratic programming algorithms. The hourly outputs of devices and responded demands are evaluated based on the dynamic purchasing and selling price of products. The results indicate that the optimal interest of the cogeneration system is the lowest among all the participants. The power proportions from gas turbine and power grid exceed 60 %, while the contribution of gas turbine decreases by 11.0 % due to the lower heat demands caused by reduced confidence level. Overall, this study offers valuable insights into the market-oriented development of solar assisted cogeneration systems.

Solar air heater with underground latent heat storage system for greenhouse heating: Performance analysis and machine learning prediction

The increasing demand for renewable energy sources in greenhouse heating, driven by the high cost of fossil fuels, has prompted the exploration of various alternatives, such as solar collectors, heat pumps, biomass, and cogeneration systems. This study aimed to establish an optimal environment for plant growth by employing a unique solar air heater and an underground latent heat storage system with a packed bed of phase change material unit (CaCl2-6H2O). Conducted in a double-span greenhouse in Ghardaia, Algeria, characterized by a semi-arid climate, the research utilized two distinct machine learning algorithms to predict the heating system's thermal behavior accurately. An experimental assessment of climatic parameters revealed that the greenhouse equipped with the heating system maintained an air temperature 57 % higher than that of a conventional greenhouse during the nighttime. The use of phase change materials resulted in the release of only 20 kJ of energy at night, indicating the potential to meet 30 % of the greenhouse's energy requirements during nighttime. Utilizing artificial neural networks, this study accurately predicted internal greenhouse parameters with and without LTES. The Nonlinear Autoregressive Exogenous (NARX) model exhibited high accuracy in prediction, with an R2 value of 0.9986 in both cases, while the Recurrent Neural Network (RNN) model showed acceptable performance, achieving an R2 value of 0.9893. These results underscore the potential of ANN models in advancing thermal energy storage technologies and their applicability in sustainable agriculture. This research significantly contributes to thermal energy storage systems and their benefits for sustainable agriculture.

Conceptual design of an innovative flexible and controllable Solar ORC cogeneration system for operating in remote areas

The instantaneous variations in environmental conditions such as solar irradiance, ambient air temperature, and wind speed may significantly affect the performance of a solar ORC system. Thus, designing a system that would be flexible, and capable of responding to any user demands despite the variations in environmental conditions is an important issue, particularly for applications in remote areas. A solar ORC system for producing electricity, freshwater, and high-temperature heating energy is introduced. The system is flexible enough to produce the desired amount of electricity and freshwater. It is achieved without changing the main operating parameters or using auxiliary equipment. The instantaneous performance of the system is investigated based on the thermodynamic models. Two integral (I) controllers are used to adjust two streams, X1 and X2, for controlling the amount of user demands in terms of electricity and freshwater. The performance and flexibility of the system in different environmental conditions are evaluated by considering three scenarios for two typical days, July 17 and January 08 at Zahedan City. As shown, the system responds well and fast to environmental conditions to meet the user’s demands. The present results show that such a system can practically and easily response to the community needs in terms of freshwater and electricity.

A new analysis for a concentrated solar power-based cogeneration system with molten salt energy storage and heat recovery steam generator – Case study – (USA, France, Canada)

This study sought to determine an optimal scenario concerning multiple climatic parameters to maximize the performance of a solar system. A molten salt energy storage unit was used to enable round-the-clock power generation and maximize the system's reliability. A solar concentrator with heliostats and a solar receiver was employed to absorb solar energy, and a modified steam Rankine cycle was utilized to generate power. A total of 12 scenarios were evaluated based on three climatic parameters (ambient temperature, sunshine duration, and wind speed) and one techno-economic parameter (number of heliostats). Sankey analysis, which is a novel technique used to determine the optimal scenarios in the literature, revealed that Scenario 8 was optimal. This scenario showed the maximum exergy rate, minimum exergy destruction, and lowest cost rate. This scenario considered the sunshine duration of 11 h, ambient temperature of 16 °C, wind speed of 3 m/s, and 300 heliostats, resulting in output energy of 1582 kWh and exergy destruction of 34250 kWh. The parametric analysis showed that the turbine and superheater temperatures had the greatest effects on the system performance. The exergy analysis of the system demonstrated that the heliostats and solar receivers accounted for the largest portions of exergy destruction. Multi-objective optimization via response surface method yielded the optimal exergy round-trip efficiency of 11.5% and optimal cost rate of 229.2 $/h. The economic analysis of the system revealed that the solar subsystem had the highest cost rate. In terms of efficiency and production power, this system will perform differently in different parts of the world and under different weather conditions. To this end, it is important to find out where this particular system will be more efficient and powerful. Six different scenarios have been defined for the parametric analysis of the proposed system in order to achieve reliable results. For the case study, Los Angeles and San Diego were selected as the regions with the highest similarity to the optimal scenario in terms of sunshine duration, ambient temperature, and wind speed, whereas Paris and Toronto were randomly selected. The performance of the system showed that the system can produce 2612.3 megawatts of electricity in the city of San Diego and 2472.4 megawatts of electricity in the city of Los Angeles. Also, by setting up this system, it is possible to provide electricity for 51 to 54 residential units. The proposed system performed better in regions with climatic parameters similar to those in the optimal scenario.

Performance analysis of a novel solar cogeneration system for generating potable water and electricity

PurposeThe utilisation of renewable energy sources for generating electricity and potable water is one of the most sustainable approaches in the current scenario. Therefore, the current research aims to design and develop a novel co-generation system to address the electricity and potable water needs of rural areas.Design/methodology/approachThe cogeneration system mainly consists of a solar parabolic dish concentrator (SPDC) system with a concentrated photo-voltaic module at the receiver for electricity generation. It is further integrated with a low-temperature thermal desalination (LTTD) system for generating potable water. Also, a novel corn cob filtration system is introduced for the pre-treatment to reduce the salt content in seawater before circulating it into the receiver of the SPDC system. The designed novel co-generation system has been numerically and experimentally tested to analyse the performance at Karaikal, U.T. of Puducherry, India.FindingsBecause of the pre-treatment with a corn cob, the scale formation in the pipes of the SPDC system is significantly reduced, which enhances the efficiency of the system. It is observed that the conductivity, pH and TDS of seawater are reduced significantly after the pre-treatment by the corncob filtration system. Also, the integrated system is capable of generating 6–8 litres of potable water per day.Originality/valueThe integration of the corncob filtration system reduced the scaling formation compared to the general circulation of water in the hoses. Also, the integrated SPDC and LTTD systems are comparatively economical to generate higher yields of clean water than solar stills.

Thermodynamic Analysis and Modeling of a Novel Solar Absorption Cogeneration System With an Adjustable Cooling-to-Power Ratio

Abstract In this work, a novel solar double-effect absorption combined cooling and power (DECCP) system with an adjustable cooling-to-power ratio is proposed. This cogeneration system uses water–LiBr as the working fluid. The novel cycle upon which this system is based has been mathematically modeled, simulated, and parametrically analyzed to generate the system’s performance characteristics for several scenarios. The performance has been compared with those of other similar combined cogeneration cycles. It was found that the proposed cycle outperforms the other cycles from the vantage point of the power produced and the cycle’s ability to produce cooling. For specific operating parameters, the DECCP cycle achieves an exergetic efficiency that varies between 36.55% and 59.13% based on the refrigerant split ratio used. An effective operating strategy is proposed for the cycle when it is powered by solar energy.

Design and economic analysis of heat exchangers used in solar cogeneration systems based on nanoworking fluid

Design and economic analysis of heat exchangers used in solar cogeneration systems based on nanoworking fluid

Design and investigation of solar cogeneration system with packed bed thermal energy storage for ceramic industry

A novel cogeneration system was designed with three different configurations integrating cogeneration system with solar-aided (Configuration-1), solar-aided with packed bed thermal energy storage (Configuration-2), solar-aided with packed bed thermal energy storage and auxiliary unit (Configuration-3). Thermo-economic-environmental analyses were performed for three designed configurations under Indian climatic conditions (20°C–50 °C).The maximum energetic and exergetic efficiencies of the three configurations were found as 44.96% and 23.14%, 51.84% and 31.22%, and 58.67% and 36.21%, respectively. Configuration-3 was best among others, and the sustainability index was 1.57. The maximum irreversibility rate has occurred for the combustion chamber, ground and wall tile dryer. The payback period for Configuration-3 was found as 4.91 years. Due to various unfavourable conditions, the payback period for Configuration-2 is 27% higher than Configuration-3. The economic optimization was performed for the higher payback period configuration, and the payback period was finally reduced to 4.88 years. The cost of the product from the cogeneration system, such as electricity and ground-wall tile was found as Rs.6.29/unit and Rs.16.11/piece for ceramic tile size of 0.10 × 0.10 × 0.007 m. The CO2/SO2/NOx emission from the three configurations was found as 1,54,090/119/230 ton/year, 1,31,341/102/196 ton/year, and 1,47,961/114/221 ton/year, respectively. Furthermore, the carbon emission saving for three configurations was obtained as 21%, 24%, and 32%, which is imperative for the environment.

Coordination control for Integrated Solar Combined Cycle thermoelectric coupling

Improving the utilization of solar energy and promoting the development of integrated energy systems, solar thermal power generation systems are researched and widely used. In the integrated solar combined cycle thermoelectric system, traditional power generation equipment as an auxiliary energy source mitigates fluctuations because of solar energy’s intermittent nature and uncertainty. However, because of the difference in response speed of different power generation equipment, it leads to imbalance of supply and demand power, which affects the smooth operation of the system. This paper proposes a novel coordination control method for integrated solar combined cycle thermoelectric coupling system. To solve the different energy response speed mismatches problem, an inertial power compensation scheme is proposed based on the established solar energy cogeneration system model, and the dynamic performance and robustness of the system are improved. In this paper, the intelligent optimization algorithm is used to optimize the parameters to improve the control precision of the controller. Finally, the paper carries out multi-scenario simulation with the 50MW solar thermal power generation and the 50MW gas turbine to verify the effectiveness and stability of the proposed coordination control method.

Modeling and Analysis of Fresnel Solar Cogeneration System with Novel Unidirectional Heat Pipe Array

Modeling and Analysis of Fresnel Solar Cogeneration System with Novel Unidirectional Heat Pipe Array

Optimized design of a novel yokeless mover permanent magnet linear generator for free‐piston stirling engines applied to solar cogeneration systems

Considering the growing environmental issues, the use of renewable energy converters such as solar cogeneration systems has received more attention during recent years. Solar cogeneration systems convert the thermal energy of solar radiation into mechanical energy (by means of a free-piston Stirling engine) and then into electrical energy (by means of a linear generator). This paper introduces the novel yokeless mover permanent magnet linear generator (YMPMLG) to reduce mover mass, increase power density, increase thrust and decrease the normal force on the mover, which can make this generator a more suitable structure for operating in solar cogeneration systems. This paper is initiated with a comparative study of a YMPMLG with two reported prototypes in this field. Three generators with similar characteristics are simulated by the finite element method (FEM). The magnetic field flux density, power density, thrust coefficient, normal force, and efficiency parameters are analysed and compared in three generators. Following that, some dimensional parameters of the YMPMLG, including generator diameter and length and permanent magnet dimensions are optimized to achieve the highest possible power density and thrust coefficient using the ‘hybrid genetic and pattern search’ algorithm. The highest power density and efficiency are 0.58 kW/kg and 90.3%, respectively. In the end, the YMPMLG prototype has been tested to validate the results of the FEM method.

A transmissive concentrator photovoltaic module with cells directly cooled by silicone oil for solar cogeneration systems

Hybrid concentrator photovoltaic-thermal systems can cogenerate electricity and heat by beam-splitting incoming concentrated light onto photovoltaic cells and a thermal receiver to increase total conversion efficiency and potentially reduce system cost. To demonstrate this, we have designed and prototyped a transmissive spectrum-splitting concentrator photovoltaic module that maximizes solar energy conversion by utilizing the entire solar spectrum. Visible light is collected using infrared-transmissive triple-junction photovoltaic cells to achieve an in-band module efficiency of 43.3% for light of wavelength λ < 873 nm, while 44.2% of out-of-band light with λ > 873 nm is transmitted through for collection by a thermal receiver. During testing on a dual-axis tracked parabolic concentrator dish at up to 166 suns, cell temperatures were maintained at 119 °C or below via a novel active cooling method. This cooling system strictly flows silicone oil directly across both sides of the cells, without inhibiting optical transmission, as verified through experimentation and simulation. The module was validated outdoors for 572 sun·hrs, and achieved a maximum thermal receiver temperature of 180 °C. 86.1% of incident solar power is collected at 166 suns average concentration collectively among the electrical, cooling, and thermal receiver subsystems. The remaining 13.9% is lost to mirror reflectivity, dish shadowing, receiver reflection, and thermal losses. The ability to directly cool the cells with an inert silicone oil offers the potential for reduced system cost relative to previous transmissive hybrid concentrator photovoltaic-thermal systems, including microfluidic-cooled designs. This solar cogeneration capability is valuable in a wide range of commercial and industrial applications.

Hybrid Renewable Resource Power Generation using Back to Back Voltage Source Converter with Output Regulation

There is a massive and rapid development in the industry and prevailing population inflation due to which the energy demand spikes. The increase in demand dilates the gap between the energy supplied and usage which makes the power quality important to consider, otherwise it causes voltage, current or frequency deviations which has unfavourable consequences in customer’s equipment or result in failure. To overcome this the concept of complementary usage of wind and solar cogeneration system is introduced along with the topology with Neutral Point Clamped inverter which has 3-level output converter that decreases the harmonics and the switching rate, it also features the regulation of the VSC through fuzzy based control scheme in the rotating reference frame of wind-solar cogeneration system with no extra DC/DC conversion stages.

Technical and environmental analysis of photovoltaic and solar water heater cogeneration system: a case study of Saveh City

Abstract The overwhelming growth in energy consumption in Iran is to the extent that in the coming years, it will turn Iran from an energy-exporting country into an energy-importing country. The use of renewable energy is essential to address this threat. In this research, the energy and economic analysis of solar energy-based cogeneration system for a building in Saveh City has been studied. The main purpose of this study is to determine the optimal size of photovoltaic cell and solar water heater by considering environmental parameters and fuel saving. In this regard, the amount of solar radiation intensity and the required loads of the building under study were determined. Then, using the SAM and TSOL relationships and software, results such as the supply of electric and thermal loads of six panels of 327 W and 3.2 m2, respectively, are needed. This system will save more than 75% energy.

Cogeneration Plants with Solar Radiation Concentrators

Results from experimental studies of a solar cogeneration system with linear photovoltaic modules of a fundamentally new design are presented. The Ʌ-shaped frontal walls are installed face-to-face at an angle to each other and mutually shield their own thermal radiation, which decreases the radiation heat losses by 27% compared with linear photovoltaic modules of the known designs. The photocurrent generated by cooled solar cells is directed to a system for charging chemical batteries and the thermal energy released is transmitted to the unconsumed intermediate heat-transfer fluid and then, through the surface of coil pipes of counter-current heat exchangers, to the consumed process water of the outer circulation circuit. The further transportation of thermal energy to the storage system occurs by natural circulation of the consumed process water through the temperature gradient formed by the control system over the height between the heat source, the heat exchanger, and the heat receiver, an insulated container (a heat accumulator). For the first time, efficient controlled transportation of heat has been implemented without using a circulation pump owing to the excess thermal energy released during the conversion of solar energy by the solar cells and a photo-selective film installed in the focal spot of the optical concentrator. Thus, a possibility of increasing the temperature of the heat-transfer fluids at the cogeneration system outlet has been offered. A two-circuit circulation system allows for separation of unconsumed heat-transfer fluids (antifreezing solutions) and the consumed fluid (the process water) by the pressure in the channels and installation of a linear counter-current heat exchanger that performs the functions of a supporting platform’s mechanical axis along the rotational axis of the optical concentrator. The system uses a dual-axis solar tracking concentrating system comprised of flat mirrors installed at an angle to the horizon. The arrangement of the Ʌ-shaped photovoltaic modules on the supporting framework in series along the heat-transfer-fluid path allows for a reduction in the overall dimensions of the channels, an increase in the total efficiency of the solar cells, and simplification of the encapsulation technology. A method for calculating the output of the cogeneration plant is provided. The method is based on the experimentally measured characteristics of silicon solar cells and heat losses in the channels of the linear photovoltaic modules.