Integration Of Solar Thermal Energy Research Articles

Solar-Assisted Carbon Capture Process Integrated with a Natural Gas Combined Cycle (NGCC) Power Plant—A Simulation-Based Study

In the realm of Natural Gas Combined Cycle (NGCC) power plants, it is crucial to prioritize the mitigation of CO2 emissions to ensure environmental sustainability. The integration of post-combustion carbon capture technologies plays a pivotal role in mitigating greenhouse gas emissions enhancing the NGCC’s environmental profile by minimizing its carbon footprint. This research paper presents a comprehensive investigation into the integration of solar thermal energy into the Besmaya Natural Gas Combined Cycle (NGCC) power plant, located in Baghdad, Iraq. Leveraging advanced process simulation and modeling techniques employing Aspen Plus software, the study aims to evaluate the performance and feasibility of augmenting the existing NGCC facility with solar assistance for post-carbon capture. The primary objective of this research is to conduct a thorough simulation of the Besmaya NGCC power plant under its current operational conditions, thereby establishing a baseline for subsequent analyses. Subsequently, a solar-assisted post-combustion capture (PCC) plant is simulated and seamlessly integrated into the existing power infrastructure. To accurately estimate solar thermal power potential at the Baghdad coordinates, the System Advisor Model (SAM) is employed. The integration of solar thermal energy into the NGCC power plant is meticulously examined, and the resulting hybrid system’s technical viability and performance metrics are rigorously evaluated. The paper contributes to the field by providing valuable insights into the technical feasibility and potential benefits of incorporating solar thermal energy into conventional natural gas power generation infrastructure, particularly in the context of the Besmaya NGCC plant in Baghdad. The power generation capacity of the plant was set at 750 MW. With this capacity, the annual CO2 generation was estimated at 2,119,318 tonnes/year which was reduced to 18,064 tonnes/year (a 99% reduction). The findings aim to inform future decisions in the pursuit of sustainable and efficient energy solutions, addressing both environmental concerns and energy security in the region.

Optimization of Concentrated Solar Power Systems with Thermal Storage for Enhanced Efficiency and Cost-Effectiveness in Thermal Power Plants

The study presents a comprehensive investigation of solar thermal systems with varying capacities and Thermal Energy Storage (TES) durations in the existing fossil fuel-run Thermal Power Plant at Ar’Ar, Saudi Arabia. The main objective is to assess the feasibility, economic viability, and environmental impact of these systems for sustainable power generation. In pursuit of sustainable energy solutions, parabolic trough systems with capacities ranging from 10 MW to 50 MW and TES durations from 0 to 8 hours were analyzed. The evaluation includes thermal and electrical assessments, field performance evaluations, and detailed cost analysis for each configuration. Multi-Criteria Decision Making (MCDM) was utilized to identify the best TES for every Concentrated Solar Power (CSP) systen with the 4 hr TES ranking first among all capacities. The research uncovers significant positive correlations between system capacity and thermal and electrical output. The 50 MW system exhibits the highest thermal output of 280.899 MW and electrical output of 180580 MW. Incorporating 4 hr TES emerges as a critical factor in enhancing system performance, optimizing the cost of electricity, and achieving a payback period within 12 years. Furthermore, the integration of solar thermal energy demonstrates substantial reductions in fossil fuel consumption. Across all capacities, the 4-hour TES system yields considerable fuel savings, ranging from 18.84 tons/hour for the 10 MW system to 96 tons/hour for the 50 MW system. These reductions correspondingly translate to considerable cost savings, with the 50 MW system reducing fuel costs by $5760. Moreover, the study highlights the crucial environmental benefits of solar thermal systems, leading to substantial CO2 emission reduction, with the 50 MW system achieving a reduction of 93452.8 kg/hour.

Current Status and Advancement in Thermal and Membrane-Based Hybrid Seawater Desalination Technologies

Emerging hybrid technologies have better potential than conventional technology for diversifying the desalination industry, which is presently being dominated by thermal and membrane-based desalination. Notwithstanding the technological maturity of the desalination processes, they remain highly energy-intensive processes and have certain disadvantages. Therefore, the hybridization of thermal and membrane desalination processes holds great attention to mitigate limitations of individual processes in terms of energy consumption, quality and quantity of potable water, overall efficiency and productivity. This paper provides an oversight of conventional and developing desalination technologies, emphasizing their existing state and subsequent potential to reduce water scarcity. Conventional hybrid desalination systems (NF-RO-MSF, MED-AD, FO-MED, MSF-MED, RO-MED, RO-MSF and RO-MD) are briefly discussed. This study reveals that the integration of solar thermal energy with desalination has a great potential to substantially reduce greenhouse emissions besides providing the quality and/or quantity of potable water in cost-effective ways. Due to its abundant availability with minimal/no carbon footprint and the ability to generate both thermal and electrical energy, solar energy is considered better than other renewable energy technologies. The findings further suggest that hybrid desalination systems are technically sound and environmentally suitable; however, a significant study of the research process and development is still required to make this technology efficient and economically viable.

Flexibility enhancement of solar-aided coal-fired power plant under different direct normal irradiance conditions

The integration of solar thermal energy into the coal-fired power plant is a cost-effective method to compensate for the solar energy intermittency. With the increasing penetration of renewable energy in the power grid, the solar-aided coal-fired power plant (SACFPP) should undertake peak-shaving tasks, which receives little attention in previous studies. This study examines the SACFPP flexibility and finds out that the reheat steam temperature easily exceeding the safety range limits the maximum load cycling rate during processes simultaneously accompanied with direct normal irradiance (DNI) disturbances. An improved control strategy is proposed accordingly to enhance the SACFPP flexibility. The feedforward control signal to regulate the flue gas damper is generated corresponding to the DNI and load cycling requirements. The effectiveness of the proposed control under sunny/cloud cover cases and actual conditions is verified. Results show that the maximum load cycling rate of a 660 MW SACFPP increases from 3.3 MW min−1to 13.2/13.2/9.9 MW min−1 under sunny/light cloud cover/strong cloud cover cases, respectively. The reheat steam temperature deviations are reduced from 9.7 °C to 4.0 °C and 18.6 °C to 4.0 °C, when DNI step decreases from 700 W m−2 to 400 W m−2 and 0 W m−2 in load up processes, respectively.

Energy and exergy analysis of a solar coffee roaster using concentrating scheffler-reflector

• An innovative solar coffee batch-type roasting system using a fixed-focus Scheffler reflector as a heat source. • Investigated thermal analysis of the solar roster unit based on energy and exergy. • Analysis provides clear insights into energy distribution and losses in the system. • The energy at the solar reflector was found to be 3680 W and out of which 66% (2449 W) was available for roasting coffee. • The integration of solar thermal energy into the roaster unit performs efficient decentralized roasting of coffee beans. The energy and exergy based thermal analysis was conducted on a newly developed solar coffee roasting system. The system is comprised of a rotating drum (diameter: 400 mm × length: 400 mm), electric motor with variable frequency drive, cooling tray (diameter: 500 mm × height: 100 mm), fan blower, and coupled with a heating source i.e., Scheffler fixed focus solar concentrator (8 m 2 ). Experiments were conducted using 2 kg coffee beans (variety Coffea arabica L .). The results revealed that the system is capable to process the complete batch in 21 ± 1 min at the temperature of 250 °C at corresponding solar radiations in the range of 800–850 W/m 2 . The specific product energy was calculated to be 1543 kJ/kg. The average exergy input, out, and loss of the solar roasting system were found to be 83.98, 47.58, and 36.40 kJ/kg, respectively. The results show that the average exergy efficiency and improvement potential factor of the solar roaster were 56.28% and 22.59 kJ/kg, respectively. Out of total available power (3680 W) at the solar reflector, 66% of energy was available for roasting coffee. The findings of this study show that the developed system could be a valuable tool for design and optimization of the energy distribution and losses at various components of the solar roasting system.

Challenges and opportunities of Solar thermal energy towards a sustainable chemical industry

The most abundant energy on Earth is solar and it is a versatile resource that is to be used to improve the sustainability of the chemical and process industry. Two main pillars support these industries, the raw materials and energy. Energy in the chemical industry is to be provided in the form of utilities such as steam, thermal energy and power. All of them can be provided by transforming solar thermal energy. This work presents the perspectives on the process integration of solar thermal plants and/or solar thermal energy within the chemical industry, describing the state of the art and the technology readiness level of units and facilities as well as the challenges and opportunities that the integration of solar thermal energy in the chemical industry generate for the process system engineering community, aiming at reaching the goals of the agenda 2030.

Identifying the optimum operating conditions for the integration of a solar loop to power an industrial flash dryer: Combining an exergy analysis with genetic algorithm optimization

With the objective to reduce fossil fuels consumption and greenhouse gas emissions, the integration of solar thermal energy into energy-intensive processes represents the most effective solution. This paper investigates the best solar integration scenarios to an industrial dryer unit through an exergy analysis. The exergetic balance for each subsystem is conducted, and a sensitivity parametric analysis was carried out. The optimization using the Genetic Algorithm was then conducted to define the optimum solar operating conditions. The exergetic evaluation showed an important exergy destruction at the dryer and combustion chamber, accounting for 58% and 42% of the inlet exergy flow, respectively. The sensitivity analysis outcomes showed that the exergy efficiency is clearly increased by increasing both drying temperature, decreasing the inlet moisture content, with preheating the combustion air temperature. Considering these variables, the optimization problem enabled enhancing the exergy efficiency by 40% and 30% for the overall process and flash dryer, respectively, when increasing drying temperature to 850 °C, an inlet moisture content of 14.9% and a preheated air combustion of 150 °C. Finally, the solar field could be integrated to the industrial dryer to preheat the ambient air for the combustion chamber to the setpoint temperature of 150 °C.

Mini cold storage using the parabolic solar trough: An appropriate technology for perishable agricultural product

Limited storage of perishable agricultural products is a common problem for small-scale farmers. Therefore, our approach for this problem is to develop a low operating cost mini cold storage using solar energy. The integration of solar thermal energy with vapor absorption refrigeration systems was studied. In vapor absorption systems, heat energy is taken as the source of input energy and the performance characteristics depend on heat energy supplied and pump work used. The novelty of our project is that it uses a parabolic solar heat collector to run a vapor absorption refrigeration system using heat energy extracted from solar energy. In this cyclic process, the refrigerating effect is produced. By utilizing this mini cold storage system, tomatoes can be stored for four weeks whereas, with room temperature storage, it only lasts one week. This appropriate technology promises small-scale farmers to keep their perishable agricultural products for several weeks without additional storage costs.

District heating network modelling for future integration of solar thermal energy

A key advantage of district heating networks is their ability to integrate different renewable energy sources, from geothermal to solar. However, the success of this integration depends on a variety of design and technical decisions, such as feed-in locations or operating temperatures, which need to be compared and analysed. For this purpose, dynamic models of district heating grids, which allow for an hourly representation of the thermodynamic conditions, are necessary. This type of models are nevertheless still uncommon, drastically limiting options to perform these comparisons accurately. To address this challenge, an open-source tool to model district heating networks is presented here and successfully applied to two case studies in western Switzerland. These simulations are then used in conjunction with simplified models of storage and solar thermal collectors to investigate, in a preliminary way, the impact of solar thermal integration on the mass flow and temperature of the network pipes, illustrating the interest of the proposed method to compare different configurations of renewable heat injections in district heating networks.

Comprehensive solar thermal integration for industrial processes

The thermal integration into industrial process is majorly focused on guarantee the heat duty and temperature level demanded by the process. Other important objectives must be considered when is integrated solar thermal energy, since its integration into industrial processes seeks to maximise its use. The present work proposes a comprehensive integration of solar thermal energy, which is based on the Pinch Analysis, and considers economical evaluation, environmental impact and the ΔTmin. The ΔTmin used to get the objectives of the solar thermal integration is denominated ΔTmin,th. The approach supposes the establishment of multiple objectives before the solar system final design. Profitable costs for two case studies, dairy and 2G bioethanol processes, were obtained. For all the scenarios, the integrated solar thermal system of dairy process was viable with zero emissions of CO2. In 2G bioethanol process, only in one scenario the solar fraction was equal to one. It is possible to reach a surplus energy of 44%, with the same absorber area of solar energy, or would be possible to reduce the area by 49% to supply the heat duties.

Integration of solar thermal energy to improve NGCC with CO2 capture plant performance

A large percentage of CO2 emissions are due to the combustion of fossil fuels for electricity generation. While a transition away from coal towards natural gas will reduce CO2 emissions, an even greater reduction in CO2 emissions can be achieved by retrofitting natural gas combined cycle (NGCC) plants with post-combustion CO2 capture (PCC) systems. A typical NGCC plant equipped with PCC was modeled in Aspen Plus and validated against similar models generated by the National Energy Technology Laboratory (NETL), and then adjusted to match the conditions of a plant located at Poza Rica, Mexico. After validation of the NGCC plant model with PCC, heat integration options were considered where heat from the flue gas cooler, CO2 dryer, and CO2 compressor intercoolers was used for heating of feedwater or low pressure (LP) steam in the steam cycle. The model was further modified to include solar-assisted carbon capture (SACC), to offset the detrimental impact of the PCC system on plant operations. The use of parabolic trough solar thermal collectors for heating of the stripper reboiler in the PCC system was considered in the Aspen Plus modeling. It was found that by using solar thermal energy for PCC reboiler heating, the LP steam extraction used to supply heat to the carbon capture reboiler element could be reduced in flow rate or eliminated depending on the quantity of solar thermal energy available. Modeling showed that if 100 % of the reboiler duty could be supplied via solar thermal energy, net plant power would increase significantly relative to the case without solar thermal collectors. The availability of the solar resource was also predicted for the target location in Mexico using the System Advisor Model (SAM) developed by the National Renewable Energy Laboratory (NREL). By coupling the modeling results from SAM with those produced by Aspen Plus, annual plant energy production for an NGCC plant with PCC and using solar thermal energy for reboiler heating was found. A final case was modeled in both Aspen and SAM, where solar thermal energy was used for LP steam heating. While this case has marginally better performance than the case where solar thermal heat was applied to the reboiler, the added complexity of this system outweighs the slight increase in net annual power generation. This modeling effort demonstrated that solar thermal heating of the stripper reboiler in an NGCC plant with PCC could meaningfully offset the detrimental impact of carbon capture on plant efficiency and power generation loss, offering an attractive renewable energy option to NGCC carbon mitigation.

A Systematisation of Methods for Heat Integration of Solar Thermal Energy in Production Processes: A Review

A Systematisation of Methods for Heat Integration of Solar Thermal Energy in Production Processes: A Review

Allocating Output Electricity in a Solar-Aided Coal-Fired Power Generation System and Assessing Its CO2 Emission Reductions in China

Coal-fired power generation in China is facing huge challenges due to its high share in the total electricity generation and its environmental problems. A solar-aided coal-fired power generation (SACPG) system, based on the integration of solar thermal energy into a conventional coal-fired power system, is an effective way to utilize solar energy and reduce coal consumption. The reasonable allocation of output electricity to solar energy and coal in a SACPG system and the evaluation of its CO2 emission reductions can help to acquire subsidies or financial support granted to renewable electricity and CO2 emission reductions. A methodology is proposed from the view of the technical characteristics of a SACPG system and the government regulation. The coal-to-electricity efficiency of the baseline unit or the coal-fired power system in a SACPG system is the key factor in the methodology, and it can be calculated on the basis of the norm of energy consumption of coal-fired power units in China. Then, the allocation of the output electricity to solar energy and coal can be calculated, and so can the CO2 emission reductions by the solar-coal hybrid system. Taking a 600 MW SACPG system as an example, the methodology is further illustrated. The methodology can guarantee that the calculation of output electricity allocation in a SACPG system and the calculation of its CO2 emission reductions are accurate, conservative and transparent for its subsidies or financial support.

Off-design performance of concentrated solar heat and coal double-source boiler power generation with thermocline energy storage

Integration of solar thermal energy into a coal-fired power station is a promising technology for many coal-dependent countries. This work investigated the off-design performance of such a dual heat source boiler power generation from a system-level modelling approach. As an example study, heat from a solar power tower (SPT) was integrated into a 660MW supercritical coal-fired power unit, and two integration schemes were considered. A system level analytical model was established that coupled the transient process of heliostat field with one-tank thermocline thermal energy storage. The off-design performance of such a hybrid system in one typical year was analyzed accordingly. The results revealed the importance of the seasonal variation of direct normal insolation (DNI), thermal energy storage scheme and integration methodology. Both the quality of sunshine and the amount of sun flux could influence the solar power efficiency; while an increase in the storage volume could decrease the discharging efficiency. Under the maximum capacity of DNI, increasing the storage capacity by 1h could improve the efficiency by 0.5–0.8%. For either integration scheme, the coal consumption could be economized at least 9×103ton per year. The maximum of solar efficiency for Scheme I, where solar energy was used to heat the superheat steam, could reach 20.42%, which also came with a penalty of reduced efficiency of thermal receiver. Under the minimum storage capacity, the solar efficiency for Scheme I was changed from 16.7% to 19.6%, while for Scheme II the change was from 14.7% to 17.3%.

Technical and economic analysis of integrating low-medium temperature solar energy into power plant

In order to mitigate CO2 emission and improve the efficiency of the utilization of solar thermal energy (STE), solar thermal energy is proposed to be integrated into a power plant. In this paper, seven configurations were studied regarding the integration of STE. A 300MWe subcritical coal-fired plant was selected as the reference, chemical absorption using monoethanolamine solvent was employed for CO2 ​capture, and parabolic trough collectors and evacuated tube collectors were used for STE collection. Both technical analysis and economic evaluation were conducted. Results show that integrating solar energy with post-combustion CO2​ capture can effectively increase power generation and reduce the electrical efficiency penalty caused by CO2 capture. Among the different configurations, Config-2 and Config-6, which use medium temperature STE to replace high pressure feedwater without and with CO2 capture, show the highest net incremental solar efficiency. When building new plants, integrating solar energy can effectively reduce the levelized cost of electricity (LCOE). The lowest LCOE, 99.28USD/MWh, results from Config-6, with a parabolic trough collector price of 185USD/m2. When retrofitting existing power plants, Config-6 also shows the highest net present value (NPV), while Config-2 has the shortest payback time at a carbon tax of 50USD/ton CO2. In addition, both LCOE and NPV/payback time are clearly affected by the relative solar load fraction, the price of solar thermal collectors and the carbon tax. Comparatively, the carbon tax can affect the configurations with CO2 capture more clearly than those without CO2 capture.

Life cycle assessment of solar aided coal-fired power system with and without heat storage

Pollutant emissions from coal-fired power system have been receiving increasing attention over the past few years. Integration of solar thermal energy can greatly reduce pollutant emissions from these power stations. The performances of coal-fired power system (S1), solar aided coal-fired power system with thermal storage (S2), and solar aided coal-fired power system without thermal storage (S3) with three capacities of each kind of system (i.e., nine subsystems) were analyzed over the entire life span. The pollutant emissions and primary energy consumptions (PECs) of S1, S2, and S3 were estimated using life cycle assessment (LCA). The evaluation value of global warming potential (GWP), acidification potential (AP), respiratory effects potential (REP) and PEC were obtained based on the LCA results. Furthermore, the system investments were estimated, and grey relation theory was used to evaluate the performance of the three types of systems comprehensively. Finally, in order to find the effect of some main factors on the solar aided coal-fired power system (SACFPS), uncertainty analysis has been carried out. The LCA results show that the pollutant emissions and PEC mainly take place in the fuel processing and operation stages for all three system types, and S2 performs the best among the three systems based on the grey relation analysis results. And the uncertainty analysis shows that with longer life span, the power system have better performance; with higher coal price, the power system will have worse performance; with lower solar collector field cost, the solar aided coal-fired power system will be more profitable than the base-case coal-fired power system.

Integration options for solar thermal with low temperature industrial heat recovery loops

This paper investigates three general methods for integrating industrial solar heating into an HRL (Heat Recovery Loop) using an industrial case study. Integration of solar thermal energy into low temperature pinch processes, like dairy and food and beverage processes, is more economic when combined with an HRL to form a combined inter-plant heat recovery and renewable energy utility system. The combined system shares common infrastructure such as piping, pumping and storage, and improves solar heat utilisation through direct solar boosting of the HRL intermediate fluid's temperature and enthalpy either through parallel or series integration relative to the other sources and sinks in the HRL system. Three options for integrating solar thermal directly into HRLs are dynamically modelled using historical plant data from a large multi-plant dairy case study to demonstrate the hot utility savings potential of the solar-HRL system. For the dairy case study, results show the best location for integrating solar heating into an HRL is in series with the heat sources as the hot fluid returns to the storage tank. This configuration maximises the effectiveness of collecting solar heat as a meaningful replacement of non-renewable process heat.

Options for Solar Thermal and Heat Recovery Loop Hybrid System Design

Integration of solar thermal energy into low temperature pinch processes, like dairy and food and beverage processes is more economic when combined with a Heat Recovery Loop (HRL) to form a hybrid inter-plant heat recovery system. The hybrid system shares common infrastructure and improves solar heat utilisation through direct solar boosting of the HRL intermediate fluid’s temperature and enthalpy either through parallel or series application. The challenge of dealing with variable solar energy supply is less of a problem in the hybrid system because the HRL with its associated storage acts as an enthalpy buffer which absorbs temperature and flow rate fluctuations on both the heat supply (including solar) and heat demand side simultaneously. Three options for integrating solar thermal directly into HRLs are applied to a large multi-plant dairy case study to demonstrate the hot utility savings potential of the Solar-HRL hybrid system. HRL performance with Variable Temperature Storage (VTS) and solar is dynamically modelled with historical plant data. The series configuration is shown to be consistently better than parallel configuration for the same thermal storage volumes and similar heat exchanger areas.

Integration of solar energy in coal-fired power plants retrofitted with carbon capture: A review

This paper reviews the utilization of solar thermal energy technology in assisting coal-fired power plants retrofitted with post-combustion carbon capture (PCC). The focus is on compensating the so-called ‘energy penalty’ imposed on the power plant output by the introduction of PCC plant operations. The integration of solar thermal energy can offset the power plant output reduction due to the PCC installation by totally, or partially providing the energy requirement of the carbon capture plant. The main process integration approaches proposed in this regard are reviewed; their advantages and drawbacks are discussed considering technical and climatic factors. The paper also discusses the merits of this hybridization of power, capture and solar plants as a transition solution for future low-carbon power generation.

Process integration of solar thermal energy with natural gas combined cycle carbon capture

This project investigates the energy cost of CO2 capture for NGCC (natural gas combined cycle) power plants and studies the effect of solar thermal energy on the energy penalty for such a system.The gas turbine used in this study is the ALSTOM GT26. Alongside the standard case, other cases include an EGR (exhaust gas recirculation) and a pre-combustion case that utilises EGR with the capture taking place after the compression stage of the gas turbine. The solar thermal technology used in these simulations is a solar tower system capable of reaching 1000 °C. The integration of the solar energy is used to provide heat to the first of the two combustion chambers in the gas turbine. Cases are optimized for 75% capture.For a NGCC it was found that using EGR decreased the specific energy penalty as well as capture energy penalty. The pre-combustion case showed a reduction in the energy penalty over the standard and EGR cases but at a reduced capture rate. The addition of solar thermal shows a reduction in the total energy penalty. This is due to a reduction in the total CO2 produced in the system, hence a reduction in the total CO2 captured.