Small Biomass Research Articles

Impact of Particle Size Polydispersity on Chemical Looping Combustion of Biomass under a Continuous Injection Mode

Particle size polydispersity considerably influences the chemical looping combustion (CLC) of solid fuels. In the present work, a three-dimensional multiphase particle-in-cell (MP-PIC) method was established and applied to study the full-loop CLC of biomass under a continuous injection mode. After model validation, the gas–solid flow characteristics, solid circulation rate (SCR), particle mixing in a fuel reactor (FR), and biomass leakage at different oxygen carrier (OC) particle size distribution (PSD) widths and biomass densities were systematically explored. The results showed that OC particles significantly stratified within the FR and both loop seals. Moreover, the fluctuation amplitude of the SCR decreased as the OC PSD width increased. Small biomass particles were more likely to leak. The number fraction of total leaked biomass particles first decreased and then increased as the OC PSD width increased. In the FR, small OC particles were primarily distributed in the upper part of the bed, and large particles were mainly distributed in the lower part. In addition, within the test range, the magnitude of the density difference between biomass and OC particles positively correlated with the likelihood of biomass leaking. These observations are all beneficial for the design and optimization of the CLC process of biomass.

Long‐Term Variation in Mesozooplankton Biomass Caused by Top‐Down Effects: A Case Study in the Coastal Sea of Japan

AbstractMesozooplankton is a key group for the recruitment of fish and global biogeochemical cycles. Four decadal observations in the coastal Sea of Japan, the marginal sea of the North Pacific, indicate that wet weight‐based mesozooplankton biomass is controlled by both environment‐induced bottom‐up and predatory‐induced top‐down processes. Interannual variations in mesozooplankton biomass using a generalized linear model approach showed a decrease in biomass during the 1980s, followed by a rapid increase in the early 1990s, and a gradual decrease in the 2010s. These interannual variations were the mirror image of those seen small pelagic planktivorous fish biomass. The difference in zooplankton biomass from the previous year was positively correlated with that of the Pacific decadal oscillation index and negatively with that of fish biomass. The latter was supported by a Granger causality analysis. Therefore, top‐down control is one of the main causes of long‐term variations of zooplankton biomass in the ocean.

Role of Tree Species, the Herb Layer and Watershed Characteristics in Nitrate Assimilation in a Central Appalachian Hardwood Forest

Forest plants that can assimilate nitrate may act as nitrate sink and, consequently, reduce nitrate losses from watershed ecosystems through leaching. This study, conducted at the Fernow Experimental Forest in West Virginia, quantified via nitrogen reductase activity (NRA) the nitrate assimilation of two tree species, red maple and sugar maple, and surrounding common herb-layer species at the tissue (foliage, roots) and plot level. NRA measurements were conducted in summer and spring. Furthermore, NRA was quantified under varying levels of soil nitrate availability due to fertilization, different stages in secondary forest succession, and watershed aspect. This study confirmed that NRA of mature maples does not respond to varying levels of soil nitrate availability. However, some herb-layer species’ NRA did increase with nitrogen fertilization, and it may be greater in spring than in summer. Combined with biomass, the herb layer’s NRA at the plot-level (NRAA) comprised 9 to 41% of the total (tree + herb-layer) foliar NRAA during the growing season. This demonstrates that the herb layer contributes to nitrate assimilation disproportionally to its small biomass in the forest and may provide a vernal dam to nitrate loss not only by its early presence but also by increased spring NRA relative to summer.

Enhancing the Phytoremediation of Heavy Metals by Combining Hyperaccumulator and Heavy Metal-Resistant Plant Growth-Promoting Bacteria.

Heavy metals (HMs) have become a major environmental pollutant threatening ecosystems and human health. Although hyperaccumulators provide a viable alternative for the bioremediation of HMs, the potential of phytoremediation is often limited by the small biomass and slow growth rate of hyperaccumulators and HM toxicity to plants. Here, plant growth-promoting bacteria (PGPB)-assisted phytoremediation was used to enhance the phytoremediation of HM-contaminated soils. A PGPB with HM-tolerant (HMT-PGPB), Bacillus sp. PGP15 was isolated from the rhizosphere of a cadmium (Cd) hyperaccumulator, Solanum nigrum. Pot experiments demonstrated that inoculation with strain PGP15 could significantly increase the growth of S. nigrum. More importantly, strain PGP15 markedly improved Cd accumulation in S. nigrum while alleviating Cd-induced stress in S. nigrum. Specifically, PGP15 inoculation significantly decreased the contents of H2O2, MDA, and in S. nigrum, while the activities (per gram plant fresh weight) of SOD, APX, and CAT were significantly increased in the PGP15-inoculated plants compared with the control sample. These results suggested that the interactions between strain PGP15 and S. nigrum could overcome the limits of phytoremediation alone and highlighted the promising application potential of the PGPB-hyperaccumulator collaborative pattern in the bioremediation of HM-contaminated soils. Furthermore, the PGP15 genome was sequenced and compared with other strains to explore the mechanisms underlying plant growth promotion by HMT-PGPB. The results showed that core genes that define the fundamental metabolic capabilities of strain PGP15 might not be necessary for plant growth promotion. Meanwhile, PGP15-specific genes, including many transposable elements, played a crucial role in the adaptive evolution of HM resistance. Overall, our results improve the understanding of interactions between HMT-PGPB and plants and facilitate the application of HMT-PGPB in the phytoremediation of HM-contaminated soils.

Differential Growth Responses of Alternanthera philoxeroides as Affected by Submergence Depths.

Global climate change has resulted in an increase in intensity and frequency of flooding, plants living in lowlands, and shore areas have to confront submergence caused by flooding, submergence-tolerant plants usually respond by adopting either escape or quiescence strategies. While certain plants exhibit a changeover from escape strategy upon partial submergence to quiescence strategy under complete shallow submergence, it remains unknown whether plants completely submerged at different water depths would adjust their strategies to cope with the change in submergence depth. Alternanthera philoxeroides is an ideal species to explore this adjustment as it is widely distributed in flood-disturbed habitats and exhibits an escape strategy when completely submerged in shallow waters. We investigated the responses of A. philoxeroides in terms of morphology, anatomy, and non-structural carbohydrate metabolism by conducting experiments using a series of submergence depths (0, 2, 5, and 9 m). During the submergence treatment, environmental factors such as light, dissolved oxygen, and temperature for submerged plants were kept constant. The results showed that A. philoxeroides plants submerged at depth of 2 m presented an escape strategy via fast stem elongation, extensive pith cavity development, and small biomass loss. However, the retarded stem elongation, reduced pith cavity transverse area, and increased biomass loss along the water depth gradient indicated that A. philoxeroides altered its growth response as water depth increased from 2 to 9 m. It is found that the changeover of response strategies occurred at higher submergence depths (5–9 m). Based on the results of our experiments, we demonstrated that water depth played an important role in driving the change in strategy. The water-depth-dependent growth performance of A. philoxeroides would benefit the species in habit exploration and exploitation. Further studies should focus on the performances of plants when submerged at varied water depths with different light climates and dissolved oxygen content, and how water depths drive the response behaviors of the submerged plants.

Thermo-economic optimization of biomass-fired organic Rankine cycles combined heat and power system coupled CO2 capture with a rated power of 30 kW

Combining organic Rankine cycle (ORC) and biomass direct combustion to form a combined heating and power system (CHP) is a feasible technology to realize small biomass power generation. A small-scale biomass-fired ORC-CHP system with a rated power of 30 kW is proposed and the thermo-economic optimization under two operation strategies is discussed. The effects of key operating parameters on exergy efficiency and levelized energy cost (LEC) are analyzed. Meanwhile, a single-objective optimization for maximum exergy efficiency or minimum LEC is addressed, and a further thermo-economic optimization is examined. The Pareto-optimal solutions using three decision makings are yielded and compared. Research demonstrates that the exergy efficiency of model A increases with condensation temperature, while the exergy efficiency of model B first increases, reaches the peak, and then slightly decreases. The split ratio has a significant effect on model B. The Pareto-optimal solutions from TOPSIS decision making are selected because of its lowest deviation index. The Pareto optimal solution for models A and B in pairs of (exergy efficiency, LEC) are (19.69%, 0.2968) and (19.75%, 0.2975), respectively. Compared to model A, model B presents higher thermodynamic performance and slightly lower economic performance.

Chitosan and chitin production and extraction in isolates of Cunninghamella sp.

The use of fungi to obtain chitin and chitosan has advantages such as handling, extraction, and production control, thus allowing to generate high quality chitosan. This study aimed to isolate and identify strains of Cunninghamella spp., and assess the production of biomass, chitin, and chitosan. We determined the macroscopic and microscopic phenotypic aspects of the superiors, mycelial growth rate index, consumption of glucose and nitrogen, as well as the pH variation, and the production of biomass, chitin, and chitosan. After assessing the mycelial growth speed index, considered fast, we found that the UFT-Ce08 and UFT-Ce09 isolates showed a higher growth speed. Therefore, we assessed the sporulation of the isolates, and all of them reached the concentration of 106 spores mL-1 in the period of 96 hours. The YPD was considered ideal for biomass production because it promotes an efficient consumption and synthesis of organic compounds by microorganisms. The assessment of the biomass production and the chitin and chitosan yield of nine isolates and the reference strain showed that the UFT-Ce08 isolate had the highest amount of biomass, the UFT-Ce11 isolate had the highest chitin yield, and despite having the second smallest biomass, the UFT-Ce09 isolate had the highest chitosan yield. Seven isolates showed higher chitosan yield than the reference strain. Therefore, chitosan production from this fungus can be further optimized to improve yield on a large-scale production. Chitosan production from this fungus can be further optimized to improve yield in large-scale production

Flame confinement in biomass combustion systems for particles abatement

This work explores the use of open-pore, inert ceramic foams with different pore sizes as particle abatement systems in small biomass combustion systems. Porous foams made of silicon carbide with pore sizes 10 to 60 pores-per-inch were installed in an in-house designed combustion unit operated with wood pellets. Their effects on the temperature distribution inside the chamber, particulate and gases emissions were studied using different airflow rates in the reaction-limited regime (low equivalence ratio) to minimise stoichiometric factors. The influence of pore size, foam position with respect to the flame and space velocity were assessed. The confinement of the flame with inert foams was found to substantially modify the temperature distribution in the combustion chamber, improve the air-fuel mixture, and favour the thermal decomposition of the pellet, leading to a reduction in particulate emissions when compared to free-flame combustion at the same experimental conditions. In general, the amount of particulate matter was found to decrease by up to one order of magnitude as the pore size of the foam was reduced, while the temperature gradient in the combustion chamber was increased. Nitrogen oxides and carbon dioxide emissions were essentially unchanged, irrespectively of the pore size of the foam. It is expected that these values will be improved with longer residence times, as happens in operations with reduced excess air ratios. These results suggest that it is possible to control pollutants derived from domestic heating within the most restrictive current regulations on particulate emissions by integrating flame confinement designs with better operating practices and efficient abatement systems.

Lithium Bonds Enable Small Biomass Molecule-Based Ionoelastomers with Multiple Functions for Soft Intelligent Electronics.

Lipoic acid (LA), which originates from animals and plants, is a small biomass molecule and has recently shown great application value in soft conductors. However, the severe depolymerization of LA places a significant limitation on its utilization. A strategy of using Li-bonds as both depolymerization quenchers and dynamic mediators to melt transform LA into high-performance ionoelastomers (IEs) is proposed. They feature dry networks while simultaneously combining transparency, stretchability, conductivity, self-healing ability, non-corrosive property, re-mouldability, strain-sensitivity, recyclability, and degradability. Most of the existing soft conductors' drawbacks, such as the tedious synthesis, non-renewable polymer networks, limited functions, and single-use only, are successfully solved. In addition, the multi-functions allow IEs to be used as soft sensors in human-computer interactive games and wireless remote sports assistants. Notably, the recycled IE also provides an efficient conductive filler for transparent ionic papers, which can be used to design soft transparent triboelectric nanogenerators for energy harvesting and multidirectional motion sensing. This work creates a new direction for future research involving intelligent soft electronics.

Growth, weed control, and nitrogen uptake of winter-killed cover crops, and their effects on maize in conservation agriculture

The utilization of winter-killed cover crops is increasing due to their benefits in intensive cropping systems based on summer cash crops. However, there is still a lack of knowledge about their management in temperate climates, where maize is planted early under conservation tillage techniques. For these conditions, here we document for the first time various agronomic effects of winter-killed cover crops under different management options. We evaluated the production, the nitrogen uptake, and the weed control of five pure winter-killed cover crop species, as well as the production of the subsequent maize and its nitrogen recovery, in four different sites. Several management options were compared (cover crop fertilization, sowing technique, and cover crop termination method). Legume cover crops (Trifolium alexandrinum L. and Vicia benghalensis L.) had a small above-ground biomass (on average 0.6 t DM ha−1 in November), while for non-legumes (Avena strigosa Schreb., Sinapis alba L., and Raphanus sativus L.) the production (on average 2.4 t DM ha−1, N uptake 89 kg N ha−1) was higher, as well as weed control and N uptake. The difference in the above-ground biomass between the two groups of cover crops was smaller at the end of winter (0.4 Mg DM ha−1), when in five out of eight site × year combinations, soil mineral N was significantly higher in a cover crop treatment compared to the no cover crop, presumably due to N release from cover crops. Cover crops did not increase maize production, and their residues did not hamper maize sowing and emergence. The recovery of cover crop N by maize was 86% for legumes and − 1% for non-legumes. We conclude that productivity, N uptake, and weed control of winter-killed cover crops (especially non-legume species) are encouraging, with no negative effects on maize yield.

Dhurrin increases but does not mitigate oxidative stress in droughted Sorghum bicolor

Main conclusionDroughted sorghum had higher concentrations of ROS in both wildtype and dhurrin-lacking mutants. Dhurrin increased in wildtype genotypes with drought. Dhurrin does not appear to mitigate oxidative stress in sorghum.Sorghum bicolor is tolerant of high temperatures and prolonged droughts. During droughts, concentrations of dhurrin, a cyanogenic glucoside, increase posing a risk to livestock of hydrogen cyanide poisoning. Dhurrin can also be recycled without the release of hydrogen cyanide presenting the possibility that it may have functions other than defence. It has been hypothesised that dhurrin may be able to mitigate oxidative stress by scavenging reactive oxygen species (ROS) during biosynthesis and recycling. To test this, we compared the growth and chemical composition of S. bicolor in total cyanide deficient sorghum mutants (tcd1) with wild-type plants that were either well-watered or left unwatered for 2 weeks. Plants from the adult cyanide deficient class of mutant (acdc1) were also included. Foliar dhurrin increased in response to drought in all lines except tcd1 and acdc1, but not in the roots or leaf sheaths. Foliar ROS concentration increased in drought-stressed plants in all genotypes. Phenolic concentrations were also measured but no differences were detected. The total amounts of dhurrin, ROS and phenolics on a whole plant basis were lower in droughted plants due to their smaller biomass, but there were no significant genotypic differences. Up until treatments began at the 3-leaf stage, tcd1 mutants grew more slowly than the other genotypes but after that they had higher relative growth rates, even when droughted. The findings presented here do not support the hypothesis that the increase in dhurrin commonly seen in drought-stressed sorghum plays a role in reducing oxidative stress by scavenging ROS.

Combustion of Aboveground Wood from Live Trees in Megafires, CA, USA

Biomass combustion is a major biogeochemical process, but uncertain in magnitude. We examined multiple levels of organization (twigs, branches, trees, stands, and landscapes) in large, severe forest fires to see how combustion rates for live aboveground woody parts varied with tree species, size, and fire severity in Ponderosa pine (Pinus ponderosa Dougl. ex Laws.) and mixed conifer-dominated forests of the Sierra Nevada, California, USA. In high severity fire patches, most combustion loss was from branches < 2 cm diameter; in low to moderate severity patches, most was from bole charring. Combustion rates decreased as fire severity declined and with increasing tree size. Pinus species had little branch combustion, leading them to have ≈50% the combustion rate of other taxa. Combustion rates could be 100% for small branch segments and up to 57% for small tree aboveground woody biomass in high severity fire patches. However, combustion rates are very low overall at the stand (0.1%–3.2%) and landscape level (0.6%–1.8%), because large trees with low combustion rates comprise the majority of biomass, and high severity fire patches are less than half of the area burned. Our findings of low live wood combustion rates have important implications for policies related to wildfire emissions and forest management.

Hydrogen Rich Product Gas from Air–Steam Gasification of Indian Biomasses with Waste Engine Oil as Binder

Production of hydrogen rich product gas through thermochemical energy conversion having the biomass gasification is making significant inroads for green hydrogen fuel generation. In the present work, detailed physical and chemical characterization, air and air–steam biomass gasification of four biomasses i.e., Kasai Saw Dust, Lemon Grass, Wheat Straw and Pigeon Pea Seed Coat from four different group of biomass production system at different steam to biomass ratio, equivalence ratio and with and without binder is analysed. Waste engine oil as an additive/binder is used. Experimental investigation for air and air–steam gasification is applied and compared. Product gas constituents, hydrogen production is examined with different steam to biomass (S/B) ratio and equivalence ratio. The equivalence ratio varies from 0.20 to 0.40 and the S/B ratio between 0 and 4. The waste engine oil (5 and 10 wt%) is mixed with the biomass during palletization. Results show maximum H2 production and HCV of product gas at an air to fuel of 0.26 and 2.4 steam to biomass ratio. This study considers the rarely studied Indian biomasses with waste engine oil as an additive for hydrogen-rich product gas production having small scale biomass gasifier.

Updraft Gasifier-Stirling Engine Biomass Incineration System Power Generation

Biomass, the world's largest renewable energy source, will continue to grow in the following energy markets. As a result, small biomass conversion systems are more competitive than large stand-alone converters because most of the biomass sources have low energy density and are widely distributed in space. The current study offers a small solid biomass power generation system to examine the possibility of direct connection of updates fixed bed gasifiers and a Stirling engine. The fixed bed updraft gasifier uses a combustion burner built into the gasifier to completely burn the synthetic gas produced by the gasifier. The exhaust gases generated by the synthesis gas combustion in the combustion tube are directed to the Stirling engine heater head. The engine then converts the heat contained in the exhaust gases. Output depends on the heat input. And the heat input is proportional to the flue gas flow rate and temperature Preliminary studies on the proposed straight couplings of the energy derived from the gasifier to mechanical energy of 300 mW and electrical energy of 50 mW. The outcomes of the Stirling engine with Updraft gasifier test shows that Pradauk biomass is more effective than charcoal biomass. Current research shows that no supplemental fuel is needed to keep the current system running smoothly. The technology and units presented can be considered as a viable solid biomass power generation system and enlarge to produce more electricity in rural areas of Thailand in the next step.
 HIGHLIGHTS
 
 The outcomes of the Stirling engine with Updraft gasifier test shows that Pradauk biomass is more effective than charcoal biomass
 The technology and units presented can be considered as a viable solid biomass power generation system and enlarge to produce more electricity in rural areas of Thailand in the next step
 Current studies show that the proposed system is technically feasible because it can generate electricity without interference so as to maintain an almost stable process
 
 GRAPHICAL ABSTRACT

The afterlife of herbaceous plant species: A litter decomposition experiment in a temperate oak-hornbeam forest

Understanding the mechanisms of singular species and their traits impacts on ecosystem functions, is crucial in the era of unprecedented anthropogenic changes of the environment, e.g. to predict changes in carbon and nutrient cycling connected with species shifts. It may allow us to take protective measurements and mitigate the negative effects of global changes. Litter decomposition is a crucial process shaping nutrient cycling in ecosystems. Studies on decomposition in forest ecosystems are mainly limited to foliar litter. In contrast to woody plant species, our knowledge of decomposition of herbaceous plants is scarce. Thus, unanswered questions remain about the model that best describes the decomposition process of herbaceous plants. The relationship of decomposition rate to functional traits is unknown for this species pool. We used the litter bag method to determine the decomposition rate of 13 herbaceous plant species and four overstory tree species growing in a temperate oak-hornbeam forest. We showed that the litter decomposition rate and C and N release were higher in spring ephemerals than summer green herbaceous species, as the plants with small total individual aboveground biomass (TAB) and small total leaf area (TLA) decomposed the fastest. Our results demonstrate that in this generally acquisitive group of plants, size traits have a stronger impact on decomposition than economic traits. For almost all species, the two-phase exponential decay model explains the course of herbaceous species litter decomposition only slightly better than the single exponential model.

Internal phosphorus cycling in macrophyte-dominated eutrophic lakes and its implications

Macrophyte-dominated eutrophication (MDE) generally exhibits different characteristics from phytoplankton-dominated eutrophication (PDE). However, the significance of P cycling on eco-environmental management of MDE lakes is still not fully recognized. In this study, P-cycling mechanism was studied in a typical MDE lake (Wuliangsu Lake, China) based on a Before-After-Control-Impact design, taking advantage of the contrasting states between its 13 sub-lakes (with/without macrophytes and with/without external water flow). Our study demonstrated that P cycling predominantly occurs through “macrophyte ↔ sediment” in the MDE lakes, rather than “water ↔ sediment” as in PDE lakes; the biodynamics of the macrophytes acts as a primary driving force for this self-enforced P cycling. Our findings challenge the present lake eutrophication management strategies, which primarily limited to the water nutrient content, and demonstrate that successful MDE lake restoration should focus on stressors caused by the sustainable “macrophyte-sediment” P cycling. Macrophyte harvesting immediately before withering is recommended as the most sustainable technique in environment management for periodically frozen shallow MDE lakes. By this technique, sediment P can be gradually pumped up by the overgrown macrophytes each year until the advent of an alternative stable state (low sediment P, small biomass, and higher diversity), thereby forming a positive feedback loop “macrophyte harvesting → less sediment P → less macrophyte → higher diversity.” Also, the catastrophic shift from MDE to PDE is no longer a concern. Furthermore, the macrophyte debris will not pose a problem as long as the macrophytes are removed during the harvest.

Harnessing versatile dynamic carbon precursors for multi-color emissive carbon dots

We report on recent advancement of CDs derived from various carbon precursors including aromatic small molecules, citric acid, biomass, polymers, petroleum products, and carbon allotropes as well as their optical based applications.

The use of a photovoltaic system in a single family house in Poland – case study

Renewable energy is becoming widely used all over the world nowadays. More single-family houses use such sources to generate heat and electricity. The article presents a case study of a house located in central Poland, in which a photovoltaic system was used, additionally with other renewable sources, such as a small wind turbine, biomass boiler and solar panels. The article describes the advantages of using renewable energy sources in the building sector considered and presents the results of experimental studies of electricity generation in a given period of time with their analysis. It turned out that the production of electricity using photovoltaic panels in autumn can support high electricity demand at this time.

Acoustic correction factor estimate for compensating vertical diel migration of small pelagics

Differences in acoustic estimates of small pelagic fish biomass, due to data acquisition during daytime and nighttime surveys, have been recognized for many years as a problem in acoustic surveys. In the absence of a single rule for all species and for all locations, some expert groups identified specific time intervals for acoustic data acquisition in relation to the schooling behavior of the target species. In the Mediterranean Sea, the research groups working in the MEDIAS (Mediterranean International Acoustic Survey) agreed on the importance that acoustic sampling are conducted only during day-time. Only when available time does not permit to complete the survey during daytime, data collection might be extended. In this case, working on data collected during both daytime and nighttime, a bias may occur in the biomass estimates. In order to evaluate and correct such bias, specific experiments were performed in some geographical sub-areas of the Mediterranean Sea. The data analysis allowed the estimation of a mean correction factor for the Strait of Sicily, where five surveys were carried out in different years. The correction factor was estimated also for the Adriatic Sea, Tyrrhenian Sea and Northern Spain; the observed variability among areas highlighted the importance of the spatial and temporal coverage of the survey area in order to obtain reliable estimates of the correction factor. Further studies are necessary to improve the interpretation of the obtained estimates in relation to area-related peculiarities such as zooplankton composition and abundance along with small pelagic fish community structure.

Solar-aided power generation in biomass power plant using direct steam generating parabolic trough collectors

Parabolic trough collectors may be used to increase the temperature of a heat transfer fluid flowing inside absorber tubes. A method of solar-aided power generation in thermal power plants is using heat transfer from the high-temperature heat transfer fluid for feed water heating. In doing so, less steam is extracted from steam turbine, and power output is increased. This paper investigates an alternative method of solar-aided power generation that uses direct steam generating parabolic trough collectors for feed water heating in a small biomass power plant. Such a power plant consists of an open feed water heater, which is more commonly known as deaerator due to its capability to remove dissolved gases from feed water. Feed water heating by solar energy in this power plant is more easily implemented by using parabolic trough collectors with direct steam generation than parabolic trough collectors with a heat transfer fluid. The proposed integration of parabolic trough collectors into a biomass power plant requires the supply of saturated steam from parabolic trough collectors to the deaerator. The steam quality reaches the maximum value when the direct normal irradiance is maximum. The performance of this system depends on the average value of effective direct normal irradiance. Simulation results show that there exists the optimum extracted steam pressure, which results in the maximum electrical energy generated by the power plant.