Exergetic and environmental life cycle assessment analysis of concentrated solar power plants (original) (raw)
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Life Cycle Environmental Impacts of Electricity Production by Solarthermal Power Plants in Spain
Journal of Solar Energy Engineering, 2008
The objectives of the analysis reported in this paper are to evaluate the environmental impacts of the electricity produced in a 17 MW solar thermal plant with central tower technology and a 50 MW solar thermal plant with parabolic trough technology, to identify the opportunities to improve the systems in order to reduce their environmental impacts, and to evaluate the environmental impact resulting from compliance with the solar thermal power objectives in Spain. The methodology chosen is the life cycle assessment (LCA), described in the international standard series ISO 14040-43. The functional unit has been defined as the production of 1 kW h of electricity. Energy use needed to construct, operate, and dismantle the power plants is estimated. These results are used to calculate the "energy payback time" of these technologies. Results were around 1 yr for both power plants. Environmental impacts analyzed include the global warming impacts along the whole life cycle of the power plants, which were around 200 g / kW h generated. Finally, the environmental impacts associated with the compliance of the solar thermal power objectives in Spain were computed. Those figures were then used to estimate the avoided environmental impacts including the potential CO 2 emission savings that could be accomplished by these promotion policies. These savings amounted for 634 kt of CO 2 equiv./yr.
Life cycle analysis of external costs of a parabolic trough Concentrated Solar Power plant
Journal of Cleaner Production, 2018
A number of developing countries have undertaken measures to diversify into renewable electricity generation. Concentrated Solar Power (CSP) is one of the technologies, though despite the high capital costs have numerous technological capabilities. CSP however is a new technology in many developing countries, where the external costs have not been fully understood. Thus far, South Africa has not conducted any detailed externalities assessments for renewable electricity sources. The presented research aims to evaluate the external cost associated with a solar CSP plant using life cycle analysis. The analysis uses a parabolic trough CSP plant with 100MW capacity located in the Northern Cape region in South Africa. The analysis evaluated external impacts and costs for climate change, human health, loss of biodiversity, local effects on crops, and damage to materials. The study found that climate change accounted for an estimated 32.2 g CO 2 eq/kWh of electricity generated. A number of non-greenhouse gas impacts were also analysed of which the effect on human health was the most significant category (0.214g/kWh). The damage cost quantified in the study for the solar CSP plant was in the range of 2.10-3.31 ZA c/kWh (1.4-2.2 €/MWh) with a central estimate of 2.83 ZA c/kWh (1.9 €/MWh). The results suggested that climate change and human health had a combined contribution of 91% to the central estimate of the external costs which was mostly attributed by the manufacturing life cycle phase. The analysis showed that manufacturing activities have a major contribution across all impact categories. A major policy understanding is that the overall damage costs can be reduced if manufacturing the main components can be localised, to reduce the emissions caused by the transport systems. This could bring added benefits for local communities and industries.
Environmental Impacts of Solar Thermal Systems with Life Cycle Assessment
2011
Solar thermal systems are an ecological way of providing domestic hot water. They are experiencing a rapid growth since the beginning of the last decade. This study characterizes the environmental performances of such installations with a life-cycle approach. The methodology is based on the application of the international standards of Life Cycle Assessment. Two types of systems are presented. Firstly a temperate-climate system, with solar thermal collectors and a backup energy as heat sources. Secondly, a tropical system, with thermosiphonic solar thermal system and no backup energy. For temperate-climate systems, two alternatives are presented: the first one with gas backup energy, and the second one with electric backup energy. These two scenarios are compared to two conventional scenarios providing the same service, but without solar thermal systems. Life cycle inventories are based on manufacturer data combined with additional calculations and assumptions. The fabrication of the components for temperate-climate systems has a minor influence on overall impacts. The environmental impacts are mostly explained by the additional energy consumed and therefore depend on the type of energy backup that is used. The study shows that the energy pay-back time of solar systems is lower than 2 years considering gas or electric energy when compared to 100% gas or electric systems.
Life Cycle Assessment of a Solar Thermal Concentrating System
2008
Solar energy could play a significant role in the replacement of fossil fuels leading to a clean energy so lution with almost zero environmental impact. However, solar energy systems have some environmental impact. The objective of this work is the investigation of the environmental impacts of the solar energy utilization, in a solar thermal concentrating system for electricity production, with the employment of Life Cycle Assessment (LCA). This work is investigating the environmental impacts for the production of 1MW of electricity in a solar power tower plant. The work will take into consideration the input and output in all life cycle stages, from the raw material excavation till the end of life stage. The material use, the energy use and the emissions produced will be investigated. The construction period is taken to be 3 years while the life time of the solar power plant is 30 years.
Thermo-economic evaluation of solar boiler power plant
Journal of thermal engineering, 2024
Today, the world is turning to use renewable energy to solve the problems of fuel shortage and pollution due to CO 2 emissions from the use of fossil fuels. In this study, parabolic trough solar collectors (PTC) with two types of heat transfer fluids HTF are used to investigate the performance of a retrofitted steam power plant using solar energy. A thermo-economic analysis was performed for a 10 MW simple steam power plant with different boiler pressure from 10 to 100 bar and located in the city of Basra in Iraq which receives high levels of solar radiation. Basra's weather conditions are used to simulate the solar-assisted regenerative system using a parabolic trough collector (PTC). According to the system analysis, it was found that increasing the boiler pressure reduces the area required for the PTC heater for constant power output. For 10 bar operating pressure the required PTC area is 64233,562 m 2 while for 100 bar operating pressure the required PTC area is 42907.59 m 2. Also, it was estimated that the Levelized Cost of Energy (LCOE) decreased with increasing operating pressure. The decrease in LCOE for PV1 heating fluid is 43.25% and the decrease in LCOE is 43.16% for the pressure range from 10 to 100 bar.
Exergoeconomic analysis of a combined solar-waste driven power plant
Renewable Energy, 2019
In this work, a thorough exergoeconomic analysis of a hybrid solar-waste driven power plant is presented. The objective is to give a clearer picture of the main irreversibilities, their corresponding costs and to find some effective yet feasible solutions to improve the efficiency and cost-effectiveness of the power plant. For this, the power plant is exergetically modeled, the exergoeconomic assessment is accomplished, the exergy losses are weighted, the cost of these losses are estimated and finally, the solutions are given. The cost of electricity was improved from 0.202 US$/MJ to 0.137 US$/MJ, after the application of the recommendations. Results show that electricity cost decreases in daily hours from a maximum of 10% in winter to the maximum of 26% in summer. Furthermore, the results of sensitivity analysis on the plant indicates that a hybrid cycle with turbine isentropic efficiency of 0.85, steam extraction ratio of 0.36 and inlet turbine temperature of 400 ℃ offers a 32% lower electricity cost compared to a cycle with a turbine isentropic efficiency of 0.75, steam extraction ratio of 0.16 and inlet turbine temperature of 500 ℃.
SOLARPACES 2018: International Conference on Concentrating Solar Power and Chemical Energy Systems, 2019
An exergy cost assessment of solar trigeneration plant to generate electricity, freshwater , and heat is carried out in order to study the process of exergy cost formation, to determine the key components that contribute to the cost of each product, and to establish the best configuration in term of unit exergy cost. The solar trigeneration plants evaluated consist of a concentrated solar power (CSP), a multi-effect distillation plant, and a process heat module, in which the CSP plant is the prime mover. The methodology includes modeling and evaluating the performance of standalone and trigeneration plants using the symbolic exergoeconomic methodology. Results show that the best configuration, in terms of exergy cost, is when the multi-effect distillation plant replaces the power cycle condenser. Regarding the costs formation, the key components which could be improved in their design are: solar collectors, evaporator, re-heater, dissipative systems, and productive subsystems.
Life cycle environmental impact assessment of a solar water heater
Journal of Cleaner Production, 2012
The technical and environmental performance of a solar water heater (SWH) is examined using the method of life cycle assessment (LCA). The present LCA study quantifies the environmental benefits of the installation of a SWH with electricity as auxiliary for domestic use in the city of Thessaloniki. Solar thermal heating produces no emissions during operation but some small levels of emissions are produced during the manufacture and installation of components and systems. This work examines the manufacturing stages of the SWH and records resource consumption and waste streams to the environment. The system boundary includes the production of raw materials such as steel, glass, copper, aluminium, glass fibber and polyurethane insulators, the manufacturing of the various parts of the SWH such as the solar collector and the heat storage tank, and finally the assembly process. The functional unit chosen is 1 MWof produced hot water. The environmental impacts taken into consideration in the study, are the greenhouse effect, ozone depletion, acidification, eutrophication, heavy metals, carcinogens, winter smog and summer smog. The system can provide 1702 kWh year1 and the solar contribution is 58.5%. The financial characteristics of the system investigated give life cycle Savings equal to 4280.0 V and pay-back time equal to 5 years.
Journal of Cleaner Production , 2012
The serious environmental degradation of our planet in the past century and the limitation of supplies of conventional fuels have led humanity to search for new energy forms. The housing sector has a big environmental impact and it makes a good candidate for changes to be implemented in order to make steps towards a sustainable society. This study deals with the exergy analysis and the Life Cycle Assessment (LCA) of solar systems for space heating, cooling and hot domestic water production. These systems will be applied to a residence in the wide Thessaloniki area, in Northern Greece. The analysis is based on the given energy needs of an average house. Furthermore, a photovoltaic system (PV) will be used for electricity production. Besides Solar energy, the existing geothermal field will be utilized via heat pumps. The system is designed to exploit solar and geothermal energy and an exergy analysis of the different elements of the system is performed so that improvements can be achieved in its efficiency and its cost be reduced. It has been shown that the exergy efficiency of the solar systems and the geothermal system are relatively low. Since almost all of the environmental impacts of the renewable energies are connected to the manufacturing of the devises for their utilization, the environmental impacts will be analyzed only at the manufacturing stage. The use of Life Cycle Assessment (LCA) will be used. It has been shown that the use of solar cooling has the highest environmental impact. This analysis applies for all regions since the energy needs could be adjusted and the solar radiation of that region taken into consideration.
Emergy evaluation of combined heat and power plant processes
Applied Thermal Engineering, 2012
An energy-focused environmental accounting method based on the embodied solar energy (emergy) principle was used for evaluating biomass and coal-based combined heat and power (CHP) cogeneration processes. The emergy method expresses all the resources needed (fuel, investment, labor etc.) as solar energy equivalents. The method looks at sustainability from the point of view of the biosphere. In fact, emergy aims to be a 'memory' of how much work the biosphere has done to provide a product.