Small-scale Heating Research Articles

Multi-software based dynamic modelling of a water-to-water heat pump interacting with an aquifer thermal energy storage system

Aquifer thermal energy storage systems may support the decarbonization of heating and cooling energy needs of urban areas, not only in heating-dominated countries but also in Southern Europe. In this framework, this work investigates the adoption of a water-to-water heat pump interacting with two aquifers and activating a small-scale district heating and cooling network serving a mixed-use district of eight residential and office buildings in Rome (Italy). The dynamic behaviour of aquifers has been replicated using the GeoSIAM software. Energy conversion systems and users’ thermal and cooling loads have been simulated in TRNSYS 18. The dynamic models have been integrated using an iterative approach based on conditions regarding plant operation and injection temperature in wells. The proposed solution has been then compared from the energy and environmental perspective with a traditional system, including an air-to-water heat pump. In addition, the balance between heating and cooling mode operation has been assessed. The results obtained encourage the adoption of aquifer thermal energy storage systems in Central Italy. Indeed, the primary energy saving, and the carbon dioxide emissions avoided are equal to 18%, whereas the imbalance between cooling and heating loads is limited to -5.2%.

High-resolution Observations of Clustered Dynamic Extreme-Ultraviolet Bright Tadpoles near the Footpoints of Corona Loops

Abstract An extreme ultraviolet (EUV) close-up view of the Sun offers unprecedented detail of heating events in the solar corona. Enhanced temporal and spatial images obtained by the Solar Orbiter during its first science perihelion enabled us to identify clustered EUV bright tadpoles (CEBTs) occurring near the footpoints of coronal loops. Combining SDO/AIA observations, we determine the altitudes of six distinct CEBTs by stereoscopy, ranging from ~1300 to 3300 km. We then notice a substantial presence of dark, cooler filamentary structures seemingly beneath the CEBTs, displaying periodic up-and-down motions lasting 3 to 5 minutes. This periodic behavior suggests an association of the majority of CEBTs with Type I spicules. Out of the ten selected CEBTs with fast downward velocity, six exhibit corrected velocities close to or exceeding 50 km s-1. These velocities notably surpass the typical speeds of Type I spicules. We explore the generation of such velocities. It indicates that due to the previous limited observations of spicules in the EUV wavelengths, they may reveal novel observational features beyond our current understanding. Gaining insights into these features contributes to a better comprehension of small-scale coronal heating dynamics.

Different manifestations of a loop-like transient brightening in solar atmospheres

Small-scale transient brightenings that are the consequence of magnetic reconnection play pivotal roles in the heating process of solar atmospheres. These phenomena contain key information about the dynamic evolution of the solar magnetic field. The fine-scale structures triggered by instabilities in these brightenings are intimately connected with the release of magnetic energy. To better understand the conversion and release of magnetic energy in small-scale heating events, we investigated the thermal-dynamical behaviors of a loop-like transient brightening (LTB) with plasma blobs. We used the spectroscopic and slit-jaw imaging observations taken from the Interface Region Imaging Spectrograph and the extreme-ultraviolet images taken from the Atmospheric Imaging Assembly on board the Solar Dynamics Observatory to analyze the plasma properties of an LTB that occurred on February 28, 2014. The space-time maps were created to present the spatial evolution of the LTB, and the light curves were calculated to illustrate the heating process. Additionally, we employed the differential emission measure (DEM) method to compute the temperature and emission measure of the LTB. In order to investigate the plasma motion along the line-of-sight direction, a double-Gaussian function was used to fit the Si IV spectral profiles. The spectrum and DEM analysis indicate that the LTB was constituted by multithermal plasma with temperatures reaching up to $5.4 $ K. The space-time maps of the emission and the Gaussian-fitting results of the Si IV line demonstrate that the LTB not only exhibited bidirectional flows, but was also twisted. Several plasma blobs were identified in the spine of the LTB, suggesting the potential presence of a tearing-mode instability. The low-temperature bands peaked approximately one minute prior to the high-temperature bands, suggesting the occurrence of a heating process driven by magnetic reconnection. The appearance of plasma blobs closely coincided with the sudden increase in the velocity and the quick rise of light curves, providing evidence that plasma blobs facilitate the release of magnetic energy during solar activity. Based on these findings, we speculate that the LTB was a complex structure that occurred in the upper chromosphere-transition region. These results clearly demonstrate that plasma blobs are important for the conversion and release processes of magnetic energy.

Assessing the Emissions and Suitability of Agro-Based Pellets for Small-Scale Residential Heating Appliances in Serbia

Assessing the Emissions and Suitability of Agro-Based Pellets for Small-Scale Residential Heating Appliances in Serbia

Effect of prediction uncertainties on the performance of a white-box model predictive controller for district heating networks

The performance of a model predictive controller (MPC) depends on the accuracy of the controller model and predictions of system disturbances. This paper studies the effect of prediction uncertainties and/or an imperfect state observer on the performance of a white-box MPC applied to a small-scale district heating network by performing a co-simulation with a detailed emulator model. This effect is studied for both a non-linear program (NLP)-based MPC and a mixed-integer NLP (MINLP)-based MPC. The results show a limited impact of prediction uncertainties when using a perfect state observer, with electricity use and thermal discomfort changing by only ▪ to ▪ and ▪/day/building to 0.56 ▪/day/building. An MPC with perfect predictions and a simple state observer only impacts the MPC's trade-off between electricity use and thermal discomfort: the former increases by 2–▪ but the latter decreases by 0.01–▪/day/building. The combined effect of both simplifications has a significant impact with an increase in electricity use and thermal discomfort of 2–▪ and 0.35–▪/day/building, but MPC still outperforms a conventional rule-based controller. The MINLP-based MPC better predicts the actual system behaviour, but its performance is similar compared to the NLP-based MPC in terms of electrical energy use and thermal comfort.

MUSE observations of small-scale heating events

ABSTRACT Constraining the processes that drive coronal heating from observations is a difficult task due to the complexity of the solar atmosphere. As upcoming missions such as the Multi-slit Solar Explorer (MUSE) will provide coronal observations with unprecedented spatial and temporal resolution, numerical simulations are becoming increasingly realistic. Despite the availability of synthetic observations from numerical models, line-of-sight effects and the complexity of the magnetic topology in a realistic set-up still complicate the prediction of signatures for specific heating processes. 3D magnetohydrodynamic (MHD) simulations have shown that a significant part of the Poynting flux injected into the solar atmosphere is carried by small-scale motions, such as vortices driven by rotational flows inside intergranular lanes. MHD waves excited by these vortices have been suggested to play an important role in the energy transfer between different atmospheric layers. Using synthetic spectroscopic data generated from a coronal loop model incorporating realistic driving by magnetoconvection, we study whether signatures of energy transport by vortices and eventual dissipation can be identified with future missions such as MUSE.

Small-scale district heating system as heat storage for decentralized solar thermal collectors during non-heating period

Solar thermal energy usage in the Baltic countries is currently low, so there is a need to find technically and economically feasible solutions to increase the appeal of this technology. Integration of solar energy into existing district heating systems is a way to increase the share of renewable energy sources while utilizing the existing infrastructure, thereby reducing capital investments, as well as mitigating the risk of solar collector overheating and eliminating the need for local storage tanks in buildings. This study presents a parametric study for evaluating the effectiveness of using a district heating system to store heat produced by decentralized solar thermal collectors and comparing the district solution to the traditional local solution. The TRNSYS 18 model was developed for this purpose. The model investigates the impact of different hot tap water demand profiles as well as pipeline diameters and lengths on system energy efficiency, showing a statistically significant difference (p < 0.05) between installing solar collectors on residential and restaurant or office roofs, and no significant difference (p = 0.24) between restaurant and office. The model shows that solar energy can be shared within a 500 m distance between neighborhoods and that a larger main pipeline diameter can increase overall system efficiency.

Potential assessment of biomass-based single-stage adsorption systems for refrigeration, cooling, and heat-pumping applications

ABSTRACT This article presents the performance estimation of a single-stage vapor adsorption system employing various carbon-based adsorbents with ethanol refrigerant, coupled with a small-scale biomass-based heating unit for space cooling, refrigeration, and heat-pumping applications. A detailed parametric investigation highlights the effects of operating temperatures, and heat exchanger to adsorbent mass ratio on specific cooling energy (SCE), coefficient of performance (COP), uptake efficiency (ηu), and mass of adsorbent to combustion fuel (mad/mcf) to identify the suitable adsorbent and sorption bed designs for each application. The numerical findings reveal that the flat-finned tube (FFT) adsorber outperforms traditional-finned tube (TFT) and tube & shell-type (T&S) adsorbers, achieving 19% and 30% higher COP, respectively, with biomass carbon-ethanol pair. The H2-treated Maxsorb-III shows the greatest optimal cooling COP (0.73), followed by the biomass-carbon (0.72) for refrigeration and space cooling. For heat pumping applications, biomass carbon-ethanol achieves the highest heat pumping COP (1.84) at a desorption temperature of 90°C, surpassing H2-treated Maxsorb-III. Further, the biomass-derived activated carbon requires the lowest amount of adsorbent per unit mass of combustion fuel in the biomass heating unit. The present thermodynamic analysis is a precursor for optimization of the potential heat-exchanger geometries and operating parameters, with the high-performance carbon adsorbents.

Data-driven compressor performance maps and cost correlations for small-scale heat-pumping applications

The performance of vapour-compression heat pumps depends crucially upon compressor selection and design. In this work, a unified modelling framework is developed to enable technoeconomic comparisons of compressors intended for small-scale heating applications (<30 kWth). Published information on 120 commercially available compressors is analysed and used to develop performance maps that predict isentropic efficiency over a wide range of working conditions. Additionally, cost correlations are established to predict price as a function of nominal compressor inlet volumetric flowrate. When rotary-vane compressors are an available option (i.e., for inlet volumetric flowrates up to 5 ∙ 10−3 m3/s), they consistently achieve a high isentropic efficiency (∼70 %) for the investigated pressure ratios (1.5–9.5). Scroll compressors have an even higher isentropic efficiency (∼75 %) at pressure ratios below 5.5, but this drops to 50 % at higher pressure ratios, while the isentropic efficiency of reciprocating-piston compressors is best (∼75 %) at higher pressure ratios (5.5–7.5). Utilising an air-source heat pump model, the compressor types are compared for countries with different weather characteristics and electricity prices. Rotary-vane compressors are associated with the lowest levelised cost of heat, but the comparison largely depends on location and heating requirements.

Solar Atmospheric Heating Due to Small-scale Events in an Emerging Flux Region

We investigate the thermal, kinematic, and magnetic structure of small-scale heating events in an emerging flux region (EFR). We use high-resolution multiline observations (including Ca ii 8542 Å, Ca ii K, and the Fe i 6301 Å line pair) of an EFR located close to the disk center from the CRISP and CHROMIS instruments at the Swedish 1 m Solar Telescope. We perform non-LTE inversions of multiple spectral lines to infer the temperature, velocity, and magnetic field structure of the heating events. Additionally, we use the data-driven Coronal Global Evolutionary Model to simulate the evolution of the 3D magnetic field configuration above the events and understand their dynamics. Furthermore, we analyze the differential emission measure to gain insights into the heating of the coronal plasma in the EFR. Our analysis reveals the presence of numerous small-scale heating events in the EFR, primarily located at polarity inversion lines of bipolar structures. These events not only heat the lower atmosphere but also significantly heat the corona. The data-driven simulations, along with the observed enhancement of currents and Poynting flux, suggest that magnetic reconnection in the lower atmosphere is likely responsible for the observed heating at these sites.

Formation of Hε in the solar atmosphere

Context. In the solar spectrum, the Balmer series line Hε is a weak blend on the wing of Ca II H. Recent high-resolution Hε spectroheliograms reveal a reversed granulation pattern and in some cases, even unique structures. It is apparent that Hε could potentially be a useful diagnostic tool for the lower solar atmosphere. Aims. Our aim is to understand how Hε is formed in the quiet Sun. In particular, we consider the particular physical mechanism that sets its source function and extinction, how it is formed in different solar structures, and why it is sometimes observed in emission. Methods. We used a 3D radiative magnetohydrodynamic (MHD) simulation that accounts for non-equilibrium hydrogen ionization, run with the Bifrost code. To synthesize Hε and Ca II H spectra, we made use of the RH code, which was modified to take into account the non-equilibrium hydrogen ionization. To determine the dominant terms in the Hε source function, we adopted a multi-level description of the source function. Making use of the synthetic spectra and simulation, we studied the contribution function to the relative line absorption or emission and compared it with atmospheric quantities at different locations. Results. Our multi-level source function description suggests that the Hε source function is dominated by interlocking, with the dominant interlocking transition being through the ground level, populating the upper level of Hε via the Lyman series. This makes the Hε source function partly sensitive to temperature. The Hε extinction is set by Lyman-α. In some cases, this temperature dependence gives rise to Hε emission, indicating heating. The typical absorption profiles show reversed granulation and the Hε line core reflects mostly the Ca II H background radiation. Conclusions. Synthetic Hε spectra can reproduce quiet Sun observations quite well. High-resolution observations reveal that Hε is not just a weak absorption line. Regions with Hε in emission are especially interesting to detect small-scale heating events in the lower solar atmosphere, such as Ellerman bombs. Thus, Hε can be an important new diagnostic tool for studies of heating in the solar atmosphere, augmenting the diagnostic potential of Ca II H when observed simultaneously.

Effects of wavy structure, ambient conditions and solar intensities on flow and temperature distributions in a mini solar flat plate collector using computational fluid dynamics

Mini solar flat plate collectors have gained traction due to their cost-effectiveness, high efficiency in converting solar radiation to heat energy, and versatility in residential and commercial applications, offering long lifespans with minimal maintenance. Optimizing the thermal performance of solar flat plate collectors using numerical simulations helps enhance their efficiency, making them even more appealing for small-scale heating and hot water applications. This study investigates the flow behavior and temperature distribution of air within a small-sized solar collector (286 × 800 × 70 mm) and optimizes its design for achieving the highest outlet air temperature. The optimization process included varying geometric parameters, such as the wavy structure hole diameter, and considering a range of operating conditions, including ambient conditions and solar intensities. This analysis aimed to understand the flow behavior and temperature distributions within the solar collector. The numerical studies provided valuable insights into the thermal and flow characteristics of the collector. The velocity distribution of the fluid within the collector aided in understanding the flow behavior, optimizing the flow path to minimize pressure drop, and maximizing heat transfer. Additionally, calculations were performed to determine total useful heat, outlet temperatures, and efficiencies. The study also discusses the optimal design and operating conditions for the collector.

Accelerated particle beams in a 3D simulation of the quiet Sun

Context. Nanoflare heating through small-scale magnetic reconnection events is one of the prime candidates to explain heating of the solar corona. However, direct signatures of nanoflares are difficult to determine, and unambiguous observational evidence is still lacking. Numerical models that include accelerated electrons and can reproduce flaring conditions are essential in understanding how low-energetic events act as a heating mechanism of the corona, and how such events are able to produce signatures in the spectral lines that can be detected through observations. Aims. We investigate the effects of accelerated electrons in synthetic spectra from a 3D radiative magnetohydrodynamics simulation to better understand small-scale heating events and their impact on the solar atmosphere. Methods. We synthesised the chromospheric Ca II and Mg II lines and the transition region Si IV resonance lines from a quiet Sun numerical simulation that includes accelerated electrons. We calculated the contribution function to the intensity to better understand how the lines are formed, and what factors are contributing to the detailed shape of the spectral profiles. Results. The synthetic spectra are highly affected by variations in temperature and vertical velocity. Beam heating exceeds conductive heating at the heights where the spectral lines form, indicating that the electrons should contribute to the heating of the lower atmosphere and hence affect the line profiles. However, we find that it is difficult to determine specific signatures from the non-thermal electrons due to the complexity of the atmospheric response to the heating in combination with the relatively low energy output (∼1021 erg s−1). Even so, our results contribute to understanding small-scale heating events in the solar atmosphere, and give further guidance to future observations.

Comparative thermo-economic analysis of co-axial closed-loop geothermal systems using CO2 and water as working fluids

Co-axial closed-loop geothermal heating systems coupling abandoned oil/gas wells face more grievous corrosion issues than the shallow ground source heat pumps due to the higher temperature and pressure conditions. Instead of water, using CO2 as a working fluid would extract more power and eliminate the corrosion issue; however, these advantages might be offset by the energy and capital cost of high operating pressure. To better guide the working fluid selection for the co-axial closed-loop geothermal heating systems, the effects of using CO2 as a working fluid on the system thermo-economic performance as well as the effects of geothermal gradients and tube diameters are evaluated. We first established a 2D thermodynamic model to simulate the heat extraction from a vertical co-axial closed loop geothermal well and the heat conduction in host rocks and then applied the key parameters into an economic model for the calculation of thermo-economic indicators. It is found that the wellbore set with smaller tube diameters can profit the thermo-economic performance of the co-axial closed-loop geothermal heating system by substantially lowering the total annual cost, promoting the energy efficiency, and slowing down the growth of cost and the descent of energy efficiency within the lifetime of the system. Besides, CO2 will be a better working fluid for small-scale co-axial closed-loop geothermal heating systems leading to lower cost per net power compared to water, and it also can slow down the descent of energy efficiency year by year.

Exposure to local, source-specific ambient air pollution during pregnancy and autism in children: a cohort study from southern Sweden

Evidence of air pollution exposure, namely, ambient particulate matter (PM), during pregnancy and an increased risk of autism in children is growing; however, the unique PM sources that contribute to this association are currently unknown. The aim of the present study was to investigate local, source-specific ambient PM exposure during pregnancy and its associations with childhood autism, specifically, and autism spectrum disorders (ASD) as a group. A cohort of 40,245 singleton births from 2000 to 2009 in Scania, Sweden, was combined with data on locally emitted PM with an aerodynamic diameter < 2.5 µm (PM2.5). A flat, two-dimensional dispersion model was used to assess local PM2.5 concentrations (all-source PM2.5, small-scale residential heating- mainly wood burning, tailpipe exhaust, and vehicle wear-and-tear) at the mother’s residential address during pregnancy. Associations were analyzed using binary logistic regression. Exposure to local PM2.5 during pregnancy from each of the investigated sources was associated with childhood autism in the fully adjusted models. For ASD, similar, but less pronounced, associations were found. The results add to existing evidence that exposure to air pollution during pregnancy may be associated with an increased risk of childhood autism. Further, these findings suggest that locally produced emissions from both residential wood burning and road traffic-related sources (tailpipe exhaust and vehicle wear-and-tear) contribute to this association.

Gaseous and particulate matter emissions from the combustion of biomass-based insulation materials at end-of-life in a small-scale biomass heating boiler

To alleviate the unbearable pressure on forests in Europe, the use of lower quality woody materials or wastes and agricultural fuels is emerging for the production of heat. The two major challenges of using these types of fuels are associated with the chemical composition variability and some fuel characteristics that could trigger potential issues throughout the burning process. This study aimed to investigate the environmental and technical performance of a small-scale multi-fuel biomass heating boiler (20 kW) fired with DINplus certified wood pellets and two granulated biomass-based insulation materials, namely hemp fibers and wood fibers under standard laboratory conditions. The boiler efficiency, particulate matter, and gaseous emissions were evaluated and compared to the legally permissible values specified in EN 303–5:2021. Hemp fiber pellets fulfilled the requirements for residential pellets, while wood fiber pellets showed lower durability and higher nitrogen and sulfur contents than the European standard limits. To respect the emissions regulation, blending wood fibers with certified wood is therefore necessary. Pellets type was noticed to significantly affect the gaseous and dust emissions but marginally the boiler efficiency. This latter was near 80 % for all fuels owing to high sensible and latent heat losses. Hemp fiber pellets showed high CO and dust emissions attributed to their high bulk density and high ash content, respectively, while the wood fiber pellets showed high NOx and SOx emissions accredited to their elemental composition. Gaseous and dust emissions were reduced through the blending of hemp and wood fibers with certified wood pellets. The particulate mass concentrations of the tested pellets fluctuated between 38 and 360 mg.Nm−3. Particulates were mainly composed of potassium, chlorine, sulfur, silicate, calcium, and zinc. From a number perspective, particles with diameters below 1 µm were dominant and their concentration varied between 104 and 106 particles.cm−3. Pelletized biomass-based insulation materials mixed with certified wood could be considered an attractive alternative fuel for residential biomass boilers.

Evaluating performances of a small-scale 50 Ω radio frequency heating system designed for home applications

Industrial-scale radio frequency (RF) heating systems have been extensively used in processing agricultural products and foods. However, small-scale RF heating systems for household applications are yet to be realized. The purpose of this study was to develop small-scale 50 Ω RF heating systems and evaluate its heating performances with cooked rice (moisture content (MC) of 62.5 ± 0.5% wet basis (w.b.)). Two RF systems (13.56 and 27.12 MHz) were developed, and the heating rate, heating uniformity, and energy efficiency of cooked rice samples were compared between the developed RF units and a 2450 MHz microwave (MW) oven under static conditions. Results showed that the RF heating systems had smaller temperature differences and better heating uniformity than the MW oven under similar overall heating rate and the same input power (700 W) levels. The 13.56 MHz RF system performed better than the 27.12 MHz one. These findings may provide some clear performance indicators and guidelines for domestic application of small-scale 50 Ω RF heating systems.

Shattering and growth of cold clouds in galaxy clusters: the role of radiative cooling, magnetic fields, and thermal conduction

ABSTRACT In galaxy clusters, the hot intracluster medium (ICM) can develop a striking multiphase structure around the brightest cluster galaxy. Much work has been done on understanding the origin of this central nebula, but less work has studied its eventual fate after the originally filamentary structure is broken into individual cold clumps. In this paper, we perform a suite of 30 (magneto)hydrodynamical simulations of kpc-scale cold clouds with typical parameters as found by galaxy cluster simulations, to understand whether clouds are mixed back into the hot ICM or can persist. We investigate the effects of radiative cooling, small-scale heating, magnetic fields, and (anisotropic) thermal conduction on the long-term evolution of clouds. We find that filament fragments cool on time-scales shorter than the crushing time-scale, fall out of pressure equilibrium with the hot medium, and shatter, forming smaller clumplets. These act as nucleation sites for further condensation, and mixing via Kelvin–Helmholtz instability, causing cold gas mass to double within 75 Myr. Cloud growth depends on density, as well as on local heating processes, which determine whether clouds undergo ablation- or shattering-driven evolution. Magnetic fields slow down but do not prevent cloud growth, with the evolution of both cold and warm phase sensitive to the field topology. Counterintuitively, anisotropic thermal conduction increases the cold gas growth rate compared to non-conductive clouds, leading to larger amounts of warm phase as well. We conclude that dense clumps on scales of 500 pc or more cannot be ignored when studying the long-term cooling flow evolution of galaxy clusters.

First looks at solar active regions with ALMA

During the first few years of observing the Sun with the Atacama Large Millimeter/submillimeter Array (ALMA), the scientific community has acquired a number of observational datasets targeting various structures in active regions, including sunspot umbra and penumbra, active region pores, and plages. In this paper we review the results obtained from the extensive analysis of these interferometric millimeter data, together with the coordinated observations from IRIS, SDO, IBIS, and Hinode, that reveal information on the chromospheric thermal structure above active regions and properties of small-scale heating events near magnetic field concentrations. We discuss the properties of waves (especially the three-minute oscillations) in sunspots, plage, and network. We speculate how high-resolution millimeter data can supplement spectral line observations in the visible and UV and can improve chromospheric spectroscopic inversions. We identify challenges in the interpretation of the millimeter continuum emission due to the complex, non-local and time-dependent processes that determine the electron density through the chromosphere. Finally we overview the prospects for future active regions observations with ALMA during the ascending phase of the solar cycle.

Multi-optimal design and dispatch for a grid-connected solar photovoltaic-based multigeneration energy system through economic, energy and environmental assessment

Solar photovoltaic-based multigeneration energy systems (SPVMES) which can use the excess energy of photovoltaic (PV) systems for heating and hydrogen production to improve the self-consumption of solar PV, have gained wide attention as a promising solution for clean and efficient production. To reliably meet diverse energy demands, gird system is integrated into a SPVMES as a backup energy source. In this paper, a grid-connected SPVMES is established to meet the electricity, heating and hydrogen loads, including PV, electrolysis, solid oxide fuel cell, electric heater for small-scale centralized heating and energy storage devices for electricity, heating and hydrogen storage, respectively. The emphasis to focus on when designing and dispatching the SPVMES lies in system performance evaluation. The innovation of this paper is to design and dispatch such a grid-connected SPVMES in a preliminary design stage through economic, energy and environmental assessment by considering cost of energy (COE), energy rate (ER) and renewable fraction (RF). Simultaneously, to explore which single objective/multi-objective optimization has better performance in comprehensive system evaluation, four different scenarios named COE optimization, RF optimization, ER optimization and multi-objective optimization are analyzed and compared. The specific application processes of component sizing and system dispatching with different optimization objectives are presented in detail. The results show that the proposed system has the COE of 0.0343$ in COE optimization scenario, the ER of 0.9128 in ER optimization scenario and the RF of 0.8811 in RF optimization scenario, which shows its significant potential in economic, energy efficiency and environmental performance. By comprehensively scoring the four optimization scenarios, it can be found that the multi-objective optimization scenario has better performance in system performance evaluation compared to the other three single objective optimization scenarios. Additionally, the multi-objective optimization could balance the tradeoff of COE, RF and ER and compromise the results of the single objective optimization scenarios. Potentially, sensitivity analysis is conducted to point out the effect of discharging depth of battery, PV subsidy, linear increasement of loads and seasonality effect on system performances.