Cost Of Solar Collectors Research Articles

Optimization of solar heating systems for office buildings in solar enriched areas with Time-zoned heating strategy

Time-zoned heating combined with solar heating system can improve building energy conservation, but the combined system design method is significantly different from conventional systems. Therefore, this study proposes a general overall optimization design method for solar heating system with Time-zoned heating mode from the overall consideration of system operational performance and building heating effectiveness. In addition, a Dual-objective optimization model that balances economic and heating performance has been proposed. Take an administrative office building with Time-zoned heating mode in Lhasa as an example, this study provides a suggested range of design parameters based on the analysis of the effects of different ratio of heat storage tanks volume to solar collector area (Vt/Ac). The optimization of solar collector area, heat storage tank volume, auxiliary heat source power, are achieved by employing levelized cost of heat (LCOH) and non-guaranteed heating hours as the optimization objectives. The study results indicate that the optimal Vt/Ac ratios are 0.02–0.04 m3/m2 for better system operational performance and 0.02–0.08 m3/m2 for better building heating effectiveness. Non-guaranteed heating hours occur mostly during the initial 1–2 h of heating start-up on weekdays. Meanwhile, when the non-heating guarantee hours are limited to 3500–4000 h, the solar heating system design scheme obtained from the optimized model has a certain degree of economic viability. Reducing the cost of solar collectors and heat storage tanks can help obtain more competitive solar heating system design solutions. The research results can provide new method and reference for designing solar heating system with Time-zoned heating mode.

Wastewater treatment to improve energy and water nexus with hydrogen fuel production option: Techno-economic and process analysis

The use of fresh water to produce green hydrogen fuel through the water electrolysis process can exacerbate the challenges of water scarcity. Using non-potable water for this purpose can lead to the design of a process with high security, reliability and sustainability. This paper develops the conceptual design and techno-economic evaluation of an innovative hydrogen energy production process from a solid oxide electrolyzer (SOE) integrated with a water treatment and recovery process. Accordingly, purified wastewater and waste heat of flue gases of the power plants have been utilized as feedstocks for the electrolysis process. Two different scenarios were assumed to supply the required thermal energy of the electrolyzer: the first scenario is the use of a preheater based on fossil energies, while in the latter scenario the required thermal energy is supplied through parabolic trough collectors, PTCs,-based solar farm. The integrating fossil fuels-driven power plants with evolving green technologies can mitigate the greenhouse gas emission crisis in addition to reducing the limitations of fossil energies. The outcomes indicated that the Levelized cost of hydrogen (LCH) for the second scenario increases by almost 38.7% compared to the first scenario. The reason for the high value of LCH for the second scenario is the high capital cost of solar collectors. Furthermore, the overall conversion efficiency for the proposed hydrogen production process was calculated as 53.26%. The introduced system can be competitive and reliable from the point of view of saving water consumption. The net potential energy saving and carbon emissions of the process was also determined.

PROSPECTS OF USING POLYMERIC MATERIALS IN THE CONSTRUCTION OF SOLAR COLLECTORS

The solar energy that reaches the Earth is free, but installations to convert solar energy into heat, as well as equipment for transporting and storage that heat, require some investment. A significant part of the components of these systems are metals. Pipelines in solar collectors and heat exchangers are made of copper, aluminum is used for the absorber and housing, and the steel is often used in heat storage tanks. One of the options to reduce the cost of solar collectors and increase their efficiency is to use polymeric materials instead of metals. The main advantages of using polymeric materials in solar thermal collectors are their cost, especially if you are taking into account the growth of the renewable energy market and rising prices for metal . The use of polymers also reduces the costs of production, transportation and installation for the user.

A decentralized water/electricity cogeneration system integrating concentrated photovoltaic/thermal collectors and vacuum multi-effect membrane distillation

Cogeneration of electricity and freshwater by integrating photovoltaic/thermal collectors and desalination systems is one of the most promising methods to tackle the challenges of water and energy shortages in remote areas. This study investigates a decentralized water/electricity cogeneration system combining concentrated photovoltaic/thermal collectors and a vacuum multi-effect membrane distillation system. The merits of such a configuration include high compactness and improved thermodynamic efficiency. To evaluate the long-term production potential of the proposed system, a thermodynamic analysis is firstly conducted. Under the climatic conditions of Makkah, Saudi Arabia, the system can convert ∼70% of the solar irradiance into useful energy. The annual productivity of electricity and distilled water are 562 kWh and 5.25 m3, respectively, per m2 of the solar collector area. Electricity and water production rates are found to be impacted by hot water flowrate, feed seawater flowrate and heat storage tank dimension, while the overall exergy efficiency stabilizes at 25–27%. Based on the production rates, a life-cycle economic analysis is then conducted. The final desalination cost is calculated to be $0.7–4.3/m3, depending on the solar collector cost and the electricity price. The derived results will enable a more in-depth understanding of the proposed solar-driven water/electricity cogeneration system.

Experimental research of electrical characteristics combined solar-electric air heater

The development and improvement of solar equipment is a necessary step in the development of solar heating systems. One of the ways to develop solar air heaters is to use new materials for the production of solar absorbers. This expands the possibility of using nozzle and capillary-porous materials in contrast to liquid solar collectors. Development and research of air heating systems with equipment made of modern textile materials is relevant. For the manufacture of absorbers it is advisable to use textile materials. This will reduce the cost of solar collectors, as well as reduce their weight and capital costs. The absorber meets requirements for both solar thermal collectors and electric heaters: high absorption capacity of solar radiation; developed heat transfer surface; relevant physical properties: low mass, resistance to ultraviolet radiation, thermal resistance, low cost for cheaper solar system; sufficient electrical resistance. A combined solar-electric air heater has been developed, which combines two main elements of any solar system – a solar heat collector and an additional heat source, the absorber of which is made of carbon graphite knitted fabric. This reduces its cost and mass and allows them to be used on existing heating facilities without the construction of bulky supporting structures to accommodate solar fields. The combined solar-electric air heater can be used as an independent heat generator for heat supply systems. To use the proposed solar-electric air heater, it is necessary to heat its absorber with an electric current, so the material from which it is made must be electrically conductive, but have sufficient electrical resistance. The use of carbon-graphite knitted fabric allows the use the direct heating of the solar energy absorber by electric current due to the corresponding electrical characteristics. This article presents the results of an experimental study of the electrical resistivity of carbon-graphite knitted fabric. These studies allow determining the electrical power of the device regardless of the size of the device. The research results presented in the article can be used only for a certain type of carbon graphite knitted fabric.

Optimal design of hybrid combined cooling, heating and power systems considering the uncertainties of load demands and renewable energy sources

The uncertainties such as loads and renewable energy sources have significant impacts on operational performances of hybrid combined cooling, heating, and power (CCHP) systems. A multi-objective stochastic optimization model of a hybrid CCHP system is proposed, which contains a gas turbine, photovoltaic/thermal collectors, an absorption chiller/heater, a ground source heat pump, and storage devices of battery and water tank. Energy hub models of energy converters and storage devices considering the off-design characteristics of the components are constructed. The uncertainties of solar irradiance and building loads are expressed in a parametric method with probability distributions. Considering the uncertainties with system reliability, the hybrid CCHP system is optimized to achieve the best energetic, economic, and environmental benefits using the non-dominated sorting genetic algorithm-II. The Pareto frontiers obtained from the case study indicated that a lower system reliability results in more energy-saving and greenhouse emission reduction benefits. When the system confidence level decreases from 0.99 to 0.50, the hybrid CCHP system compared to the conventional separate production system averagely saves 13.7% primary energy and reduces 8.0% carbon dioxide emission. However, the annual cost saving rate will be reduced with the decrease in system confidence level and increase in uncertainty. The sensitivity analysis of Pareto frontiers on key economic parameters is performed and the results demonstrated that the annual cost saving rate is more sensitive to natural gas price, and the investment cost of solar collectors has a stronger impact than gas turbine.

Solar Integrated Anaerobic Digester: Energy Savings and Economics

Industrial anaerobic digestion requires low temperature thermal energy to heat the feedstock and maintain temperature conditions inside the reactor. In some cases, the thermal requirements are satisfied by burning part of the produced biogas in devoted boilers. However, part of the biogas can be saved by integrating thermal solar energy into the anaerobic digestion plant. We study the possibility of integrating solar thermal energy in biowaste mesophilic/thermophilic anaerobic digestion, with the aim of reducing the amount of biogas burnt for internal heating and increasing the amount of biogas, further upgraded to biomethane and injected into the natural gas grid. With respect to previously available studies that evaluated the possibility of integrating solar thermal energy in anaerobic digestion, we introduce the topic of economic sustainability by performing a preliminary and simplified economic analysis of the solar system, based only on the additional costs/revenues. The case of Italian economic incentives for biomethane injection into the natural gas grid—that are particularly favourable—is considered as reference case. The amount of saved biogas/biomethane, on an annual basis, is about 4–55% of the heat required by the gas boiler in the base case, without solar integration, depending on the different considered variables (mesophilic/thermophilic, solar field area, storage time, latitude, type of collector). Results of the economic analysis show that the economic sustainability can be reached only for some of the analysed conditions, using the less expensive collector, even if its efficiency allows lower biomethane savings. Future reduction of solar collector costs might improve the economic feasibility. However, when the payback time is calculated, excluding the Italian incentives and considering selling the biomethane at the natural gas price, its value is always higher than 10 years. Therefore, incentives mechanism is of great importance to support the economic sustainability of solar integration in biowaste anaerobic digestion producing biomethane.

Experience with Unglazed Solar Collectors in District Heating Systems

Over the past decade, the solar industry in Russia has been rapidly developing, and its technical means have become cheaper. The effort of general engineering has been focused on the technology of photovoltaic converters; its commercial indicators and implementation level now prevail over that of liquid solar collectors. In some cases, however, solar collectors can still be cost-effective, e.g., if the consumer does not have alternative low-cost energy sources, such as natural gas or low-cost electricity from a centralized supply system. Nevertheless, some applications can be identified where they will be proved competitive and economically viable even within centralized energy supply systems. This paper discusses an example of efficient implementation of unglazed solar collectors mounted on the roof of central heat supply gas stations for pre-heating cold water in the city of Gelendzhik, Krasnodar krai. The low cost of generated heat, 0.005 USD (kWh)–1 with the cost of solar collectors being 107 USD m–2, is ensured by the simplicity of the chosen system design. The payback period was less than 3 years. The experience of using unglazed solar collectors in a district heating system of Gelendzhik has proved to be successful and can be recommended for distribution under similar climate conditions.

Effect of solar utility temperature to costing and design parameters of integrated solar thermal system

The objective of this research is to evaluate the trade-off between solar utility temperature and solar collector efficiency, in the context of Malaysia, and also evaluating the proposed system efficiency and economic feasibility. Since Malaysia receives an abundance amount of solar radiation throughout the year, generating thermal energy from solar thermal energy system is highly attractive. In the illustrative case study, flat plate collector (FPC) and compound parabolic collector (CPC) were used for evaluation of integration with different temperature process. For each process, configuration with and without HEX were evaluated. Generally, solar collector cost for configuration with HEX is more than configuration without HEX, solar collector cost will be lower when solar utility temperature is lower, and effect of solar utility temperature variation affect more on FPC than on CPC. The results show that annual saving is 174,952 MYR/y. The payback period for all processes vary from 4.7 to 7.6 y.

Performance comparison and optimal parameters evaluation of solar-assisted NH3–NaSCN and NH3–LiNO3 type absorption cooling system

This paper represents the detailed thermodynamic study to compare the performance of solar energy-assisted ammonia–sodium thiocyanate (NH3–NaSCN) and ammonia–lithium nitrate (NH3–LiNO3) absorption cooling system coupled with various solar collectors. A 15-kW absorption cooling system at evaporator temperature − 5 °C is considered and analyzed integrated with flat plate collectors (FPC), evacuated tube collectors (ETC), flat plate with compound parabolic collector reflectors and parabolic trough collectors (PTC) connected with storage tank to operate the absorption system. In this study, minimum generator (cut-off) temperature to operate the system is evaluated for both NH3–NaSCN and NH3–LiNO3 working pairs. Analysis of variance is performed to find out most critical operational parameters for cut-off temperature. In addition, the influence of heat source temperature on energetic, exergetic and economic aspects of systems is depicted. Exergetic optimization of each system estimated the required optimum collecting area for cooling. Required capital cost of solar collector at optimized area is also evaluated. The performance comparison from thermodynamic perspectives shows that NH3–LiNO3 coupled with ETC is superior to NH3–LiNO3 coupled with FPC. NH3–LiNO3 VARS coupled with PTC exhibited 23% higher value of optimized cost and 0.7% higher value of $$\eta_{{{\text{II}},{\text{system}}}}$$ in comparison with NH3–LiNO3 integrated with ETC. Key performance indicator is evaluated for the selection of optimum system. On the basis of key performance indicator, NH3–LiNO3 system coupled with ETC is recommended by considering thermodynamic and economic criteria.

Economic Evaluation of Solar Cooling Schemes

This paper provides an economic evaluation and comparison of ejector, absorption and vapor compression systems driven either partly or fully by solar energy. Life cycle costing has been used to assess the relative economic ranks of eight solar cooling schemes. It has been shown that the capital cost of solar collectors is the dominant capital cost item in the total inventory of solar cooling plant, which has a strong influence on the system life cycle costs. Lower collector costs are therefore critical in establishing economically viable solar cooling systems. Primary energy analysis has been carried out and the running costs of chillers were determined for the maximum range of thermal and electric solar fractions and a number of annual equivalent full load hours of operation. The results indicate that two low temperature flat-plate collector assisted single-effect absorption chillers compete favorably with a PV assisted centrifugal mechanical compression chiller across the maximum range of thermal and electrical solar fractions. Low temperature options for solar cooling have been shown to be more economical than their high temperature counterparts. At current collector prices, solar cooling systems are still not cost effective compared with conventional centrifugal cooling systems, however, it is shown that at a collector cost of £57/m2 for thermal energy and £1.8/Wp for electrical energy, single-effect solar absorption and PV-centrifugal compression could become cost effective within an annual EFLH of 5840 hours. As such, the paper presents technical guidance on the procurement and operation of solar cooling plant. The novel energy and cost calculation methodology developed here can be applied globally to a wide range of solar collectors, chillers, heat rejection and ancillary subsystems.

Parametric study and cost analysis of a solar-heating-and-cooling system for detached single-family households in hot climates

A solar-heating-and-cooling (SHC) system, consisting of a flat-plate solar collector array, a hot water storage tank, and an absorption chiller unit is designed and modeled to satisfy thermal loads (space heating, domestic hot water, and space cooling). The system is applied for Nicosia, Cyprus, a location with prolonged summer-like conditions, where heating demand is moderate, while space cooling demand is comparatively very high. The study investigates the potential of a solar system installed and operated onsite in a detached single-family household to satisfy all necessary thermal loads. The hot water storage tank is also connected to an auxiliary heater (diesel-fired boiler) to supplement solar heating, when needed. The main purpose of the study is to model the overall system and contact a parametric study that will determine the optimum economic system performance in terms of design parameters. The system is compared, through a cost analysis, to an electric heat pump (EHP) system. It is found that the optimum system combination of solar collector area and volumetric capacity of the hot water storage tank is 70m2 and 2000L, respectively. The total annualized cost (in USD) for the optimum SHC system is $3,719. The sensitivity analysis showed that the SHC system would be unfavorable to compete with EHP technology, if the solar collector cost is above $360/m2.

Hybrid optimization algorithm for thermal analysis in a solar parabolic trough collector based on nanofluid

In recent years, many research works focused on improving and reducing the cost of solar collectors. This paper focuses upon the development of an efficient modeling and optimization of solar collector. The approach adopted in modeling utilizes a parabolic trough collector absorber tube with non-uniform heat flux, fully developed mixed convection flow and Al2O3/synthetic oil as a base fluid. Optimization of thermal analysis in a solar trough collector using nanofluid is non-convex, non-linear and computationally intensive process. In order to overcome these difficulties, a hybrid optimization method involving GA (genetic algorithm) and SQP (sequential quadratic programming) is introduced in the optimization process. The optimization problem used in this study involves maximization of a non-dimensional correlation consisting of Nusselt number and pressure drop with Reynolds and Richardson number which are used as design constraints. The methodology implemented within an integrated environment involving Matlab, Gambit and Fluent. The results obtained show that heat transfer enhancement has a direct relationship with the nanoparticle concentration ratio whereas it has inverse relationship with the operational temperature. In addition, the results show that the proposed methodology provides an effective way of solving thermal analysis in a solar parabolic trough collectors based on simulation models.

Nonparabolic solar concentrators matching the parabola.

We consider the limit of geometric concentration for a focusing concave mirror, e.g., a parabolic trough or dish, designed to collect all radiation within a finite acceptance angle and direct it to a receiver with a flat or circular cross-section. While a concentrator with a parabolic cross-section indeed achieves this limit, it is not the only geometry capable of doing so. We demonstrate that there are infinitely many solutions. The significance of this finding is that geometries which can be more easily constructed than the parabola can be utilized without loss of concentration, thus presenting new avenues for reducing the cost of solar collectors. In particular, we investigate a low-cost trough mirror profile which can be constructed by inflating a stack of thin polymer membranes and show how it can always be designed to match the geometric concentration of a parabola of similar form.

Method of evaluation of solar collector cost under fuel price change

When we take into account the problems of large-scale use of solar energy, the matters of economic perspectives of solar plants in the future become vital. We present the method on whose basis evaluation of the cost of solar collectors is performed taking into account the change in the fuel prices. The method is based on the approach to evaluation of the cost of energy generated by the solar plants offered previously by the authors. Assuming that the components of expenditures for production are not changed, we obtained that the cost of solar collectors will grow, at approximately the same ratio as the growth of the prices for fuel (energy). Thus, the problem of creation of the economically effective solar collectors should be solved already today, at the existing prices for materials and fuel. At present, it is assumed that competitiveness of the solar plants will increase with the growth of the fuel prices.

Solar-assisted Post-combustion Carbon Capture feasibility study

Solvent-based Post-combustion Carbon Capture (PCC) is one of the promising technologies for reducing CO 2 emissions from existing fossil-fuel power plants due to ease of retrofitting. A significant obstacle in widely deploying this technology is the power plant output reduction (Output Power Penalty – OPP) due to the energy intensive CO 2 separation process. In this paper we propose and theoretically evaluate a system to reduce the OPP by providing part of the PCC energy input using solar thermal energy. It is hypothesized that reducing the OPP during the daytime coincides with peaks in wholesale electricity prices thus increasing the revenue stream for a solar-assisted PCC (SPCC) plant. The general framework for assessing and sizing an SPCC system is presented. A techno-economic assessment is performed as a case study for a 300 MW e pulverized coal power plant in New South Wales, Australia using actual weather and wholesale electricity price data. It is shown that the proposed technology can be economically viable for solar collector costs of US$100/m 2 at current retail electricity prices and optimal Solar load-Fraction (SF) of 22% (SF is the portion of solvent regeneration energy provided by solar energy). The convergence of increasing electricity prices and decreasing collector costs improves SPCC viability at higher SF.

Technical and economical analysis of a solar–geothermal hybrid plant based on an Organic Rankine Cycle

A combined concentrating solar power system and a geothermal binary plant based on an Organic Rankine Cycle (ORC) is analyzed. Given a supercritical ORC, designed for the optimal utilization of an intermediate enthalpy geothermal source, a solar parabolic trough field was included in the plant, introducing an additional high temperature heat source for the cycle and increasing power production. The off-design performance analysis of the power cycle was performed first. An hour-by-hour simulation was then carried out to estimate the yearly production using a detailed solar field model. Finally, a differential economic analysis was performed to determine the cost of the additional electricity generated with the solar source. On the basis of the current cost of solar collectors, levelized costs of electricity of 145–280 €/MWh were obtained depending on the location of the plant: a competitive value with respect to large, stand-alone concentrating solar power plants.

Optical and electrical properties of flash-evaporated amorphous CuInSe 2 films

A combined concentrating solar power system and a geothermal binary plant based on an Organic Rankine Cycle (ORC) is analyzed. Given a supercritical ORC, designed for the optimal utilization of an intermediate enthalpy geothermal source, a solar parabolic trough field was included in the plant, introducing an additional high temperature heat source for the cycle and increasing power production. The off-design performance analysis of the power cycle was performed first. An hour-by-hour simulation was then carried out to estimate the yearly production using a detailed solar field model. Finally, a differential economic analysis was performed to determine the cost of the additional electricity generated with the solar source. On the basis of the current cost of solar collectors, levelized costs of electricity of 145–280 €/MWh were obtained depending on the location of the plant: a competitive value with respect to large, stand-alone concentrating solar power plants.

Techno-economic analysis of a multi-stage stacked tray (MSST) solar still

A techno-economic analysis of multi-stage stacked tray (MSST) solar still coupled with a solar collector through a heat exchanger has been developed. Various heat and mass transfer phenomena have been considered for evaluating its distillate output. The economic analysis takes into account capital and maintenance costs, and life of the system and estimates the cost of unit mass of distilled water ( C u ). In order to appreciate the developed model, numerical calculations have been made to optimize different design parameters, namely number of stages, evaporation surface area and collector area corresponding to climate of Delhi, India. The effect of useful life of the distillation unit on the cost of unit mass of distilled water has also been discussed. The study also includes a discussion on the sensitivity of cost of unit mass of distilled water in reference to the useful life of distillation chamber, cost of solar collector and other associated parameters.

Performance Predictions of Solar Open-Cycle Absorption Air Conditioning Systems in Three Climatic Regions

Open-cycle absorption air conditioning is a promising type of solar-driven cooling system. It addresses, in a significant way, the problems of high solar collector costs and power requirements that are inherent in other solar cooling systems. Previous open-cycle absorption modeling studies have been very limited and included only the solar collection part of the system. The purpose of this study was to evaluate the potential for use of this type of system in various climatic regions of the United States. The study examines this promising type of air conditioning as a total system interacting dynamically with its environment. Mathematical analysis and computer simulation were used. System simulations were performed for three system design concepts. The Typical Meteorological Year data base for Miami, FL, Washington, D.C., and Phoenix, AZ, were used to estimate system potential. The best performance predictions resulted in approximately 60 percent of the seasonal load being met by an open-cycle absorption system in Miami, 70 percent in Washington, and 99 percent in Phoenix.