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[en] The interest and motivation for harnessing wind power have grown tremendously during the nineteen-eighties in many developed countries as a result of frequent energy crises on the one hand and persisting issues of environmental pollution on the other. These activities have stimulated at the same time, the scientific and research community in Jordan to launch a serious series of investigations into the reality of wind energy potentials in the country. This study examines in detail the plausibility of utilising wind as an alternative source of energy in Jordan. The task is accomplished by reviewing the history of the measurements performed in the early days by the meteorological department up to full involvement by the Royal Scientific Society in 1981. This is followed by data evaluation and resource analysis, yielding a regional classification as a result of matching between the systems and the sites' power distribution. In addition, the cost of wind energy in Jordan Dinar per kWh is outlined for the various wind regions in order to show their cost-competitiveness with conventional power generation. (Author)
[en] A study is presented in which an optimisation model is built to determine the economic viability of three small biofuel fired CHP plants. The model formulated to describe heat and electricity production with CHP plants is based on simulation data for three existing plants. The modeled system extends from the production facilities to the district heating substations of the consumers, thus combining operational and design planning. We find that, compared to the long term average situation in the Nordic countries, higher electricity prices or lower investment costs are needed to make CHP plants attractive in small district heating networks. The results are relatively sensitive to the original economic parameters, and this uncertainty over future cash flows may further reduce investments in small CHP plants. (author)
[en] This study considers both the internal and external costs of the utility in deriving the avoided capacity cost (ACC) and avoided operating cost (AOC) induced in an electric utility caused by the implementation of a demand side management program (DSM). In calculating the ACC, a multiple objective linear programming model is developed. Meanwhile, the AOC is calculated by considering the differences between the total and specific time period energy consumption ratios before and after the implementation of the DSM program. This study also develops an economic analysis method using Net Present Value and Pay Back Year models to assess the economic profitability of implementing a DSM program from a participant's point of view. The design and construction of a partial load leveling eutectic salt Cooling Energy Storage (CES) air conditioning system in a target office building in Kaohsiung, Taiwan, is discussed in order to simulate the cost benefit of the CES system from the perspective of the utility and from that of the participant. The results confirm the effectiveness of the developed models in simulating the economic benefits of implementing a DSM program from the perspectives of both the utility and the participant
[en] A cost evaluation of CO2 sequestration by aqueous mineral carbonation has been made using either wollastonite (CaSiO3) or steel slag as feedstock. First, the process was simulated to determine the properties of the streams as well as the power and heat consumption of the process equipment. Second, a basic design was made for the major process equipment, and total investment costs were estimated with the help of the publicly available literature and a factorial cost estimation method. Finally, the sequestration costs were determined on the basis of the depreciation of investments and variable and fixed operating costs. Estimated costs are 102 and 77 EUR/ton CO2 net avoided for wollastonite and steel slag, respectively. For wollastonite, the major costs are associated with the feedstock and the electricity consumption for grinding and compression (54 and 26 EUR/ton CO2 avoided, respectively). A sensitivity analysis showed that additional influential parameters in the sequestration costs include the liquid-to-solid ratio in the carbonation reactor and the possible value of the carbonated product. The sequestration costs for steel slag are significantly lower due to the absence of costs for the feedstock. Although various options for potential cost reduction have been identified, CO2 sequestration by current aqueous carbonation processes seems expensive relative to other CO2 storage technologies. The permanent and inherently safe sequestration of CO2 by mineral carbonation may justify higher costs, but further cost reductions are required, particularly in view of (current) prices of CO2 emission rights. Niche applications of mineral carbonation with a solid residue such as steel slag as feedstock and/or a useful carbonated product hold the best prospects for an economically feasible CO2 sequestration process. (author)
[en] Highlights: • It addresses the size and cost estimation of cascaded refrigeration system. • Cascaded system is a promising decarburizing and energy efficient technology. • Second law analysis is carried out with modified Gouy-Stodola equation. • The total annual cost of plant operation is optimized in present work. - Abstract: This paper addresses the size and cost estimation of vapor compression–absorption cascaded refrigeration system (VCACRS) for water chilling application taking R410a and water–LiBr as refrigerants in compression and absorption section respectively which can help the design engineers in manufacturing and experimenting on such kind of systems. The main limitation in the practical implementation of VCACRS is its size and cost which are optimized in the present work by implementing Direct Search Method in non-linear programming (NLP) mathematical model of VCACRS. The main objective of optimization is to minimize the total annual cost of system which comprises of costs of exergy input and capital costs in monetary units. The appropriate set of decision variables (temperature of evaporator, condenser, generator, absorber, cascade condenser, degree of overlap and effectiveness of solution heat exchanger) minimizes the total annual cost of VCACRS by 11.9% with 22.4% reduction in investment cost at the base case whereas the same is reduced by 7.5% with 11.7% reduction in investment cost with reduced rate of interest and increased life span and period of operation. Optimization results show that the more investment cost in later case is well compensated through the performance and operational cost of the system. In the present analysis, optimum cascade condensing temperature is a strong function of period of operation and capital recovery factor. The cascading of compression and absorption systems becomes attractive for lower rate of interest and increase life span and operational period
[en] Highlights: • Mathematical modeling for the energy yield in Mirror Augmented PV systems. • Simplified analytical expression for skyview factor applicable to MAPV. • Economic appraisal of MAPV systems: NPV, DPBP, IRR and LCC. - Abstract: In the last years, solar photovoltaic (PV) systems have had great impetus with research and demonstration projects, both in Italy and other European countries. The main problems with solar PV are the cost of solar electricity, which is still higher compared with other renewables (such as wind or biomass), due to the cost of semi-conductors, and the low conversion efficiency. However, PV panel prices are rapidly decreasing benefiting from favorable economies of scale. For instance, according to the Energy Information Administration (EIA) the US average levelized costs for plants entering service in the 2018 should be 144.3$/MW h for solar PV, whereas 111.0$/MW h for biomass and 86.6$/MW h for wind (Levelized Cost of New Generation Resources in the Annual Energy Outlook, 2013). In order to increase the electric yield of PV modules (which can be even doubled with respect to constant tilt configurations), without significantly increasing the system costs, it was decided to consider the addition of inclined mirrors at both sides of the PV modules, so as to deflect more solar rays towards them, as in Mirror-Augmented Photovoltaic (MAPV) systems. The system preserves its constructive simplicity with commercial flat PV modules even though dual axis tracker must be implemented, since MAPV systems harness mainly the direct radiation. The performance analysis of MAPV systems starts from the calculation of the global irradiation on the surface of the PV module which is a sum of the direct sunlight on it and the irradiation reflected by the mirrors. A mathematical model of a MAPV system is presented, which takes into account not only the increase of direct (or beam) radiation, due to the mirrors, but also the reduction of both the diffuse and reflected radiations due to the shadowing effect of the flat mirrors. In particular, under an isotropic sky assumption, a simplified analytical expression, applicable in the case of MAPV systems, for the sky-view factor has been developed. The deterioration in the performance of the PV system as a result of the increasing cell temperature with radiation augmentation due to mirrors has been also evaluated. Moreover, in order to provide a more realistic view of the process, the energy analysis is accompanied by the exergy analysis. Finally, in order to analyse the economics of MAPV systems, Net Present Value, Discounted Payback Period, Internal Rate of Return and Life-Cycle Costs, have been considered and compared with both a constant tilt building-integrated photovoltaic (BIPV) system and a system with a dual axis tracker
[en] In this paper, an optimal risky bidding strategy for a generating company (GenCo) by self-organising hierarchical particle swarm optimisation with time-varying acceleration coefficients (SPSO-TVAC) is proposed. A significant risk index based on mean-standard deviation ratio (MSR) is maximised to provide the optimal bid prices and quantities. The Monte Carlo (MC) method is employed to simulate rivals' behaviour in competitive environment. Non-convex operating cost functions of thermal generating units and minimum up/down time constraints are taken into account. The proposed bidding strategy is implemented in a multi-hourly trading in a uniform price spot market and compared to other particle swarm optimisation (PSO). Test results indicate that the proposed SPSO-TVAC approach can provide a higher MSR than the other PSO methods. It is potentially applicable to risk management of profit variation of GenCo in spot market.
[en] An original methodology for the analysis of systems and processes is developed. The methodology is based on the quantities exergy, cost, energy and mass, and is referred to as EXCEM analysis. The development of a code for EXCEM analysis by enhancing Aspen Plus, a state of the art process simulation code, is described. Applications of the methodology and code to the analysis of several engineering processes (production of electricity, hydrogen and hydrogen derived fuels) are discussed. The relations between exergy loss and capital cost and those between exergy and environmental impact are investigated. EXCEM analysis may prove useful to investigators in engineering and other disciplines
[en] In this paper, we have proposed a novel integrated gasification combined cycle (IGCC) system with steam injected H2/O2 cycle and CO2 recovery. A new evaluation criterion for comprehensive performance of the IGCC system has also been presented. The thermodynamic characteristics, environmental and comprehensive performance of the new system have been investigated based on comparison of different IGCC systems with O2/CO2 cycle. The promising results show the new system has less energy penalty for separating and recovering CO2, an efficiency decrease of less than 1 percentage point. The ratio of CO2 penalty price to fuel price is an important factor influencing the comprehensive performance of this system. The performance of the IGCC with O2/CO2 cycle and syngas separation is better than that with the simple semi-closed O2/CO2 cycle. The above research achievements will provide valuable information for further study on IGCC systems with low CO2 emission
[en] Highlights: • Feasibility and load sensitivity analysis is conducted for PVPS. • Battery and diesel generator are considered as supporting units to the system. • The configuration of the PV array and the initial status of the tank are important. • The COU is more sensitive to the capital cost of PV array than other components. • Increasing the maximum capacity of water storage tank is better storage and DG. - Abstract: In this paper, a feasibility and load sensitivity analysis is conducted for photovoltaic water pumping systems with storage device (battery) or diesel generator so as to obtain an optimal configuration that achieves a reliable system. The analysis is conducted based on techno-economic aspects, where the loss of load probability and life cycle cost are represented as technical and economic criteria, respectively. Various photovoltaic water pumping systems scenarios with initially full storage tank; battery and hybrid DG-PV energy source are proposed to analyze the feasibility of system. The result shows that the configuration of the PV array and the initial status of the storage tank are important variables to be considered. Moreover, the sensitivity of cost of unit for various PVPS components is studied. It is found that the cost of unit is more sensitive to the initial capital cost of photovoltaic array than other components. In this paper a standalone PV based pumping system with a PV array capacity of 2.4 kWp and a storage tank with a capacity of 80 m3 was proposed an a optimum system. The system with the aforementioned configuration pumps an average hourly water volume of approximately 3.297 m3 over one year with a unit of 0.05158 USD/m3. Moreover, according to results, increasing the maximum capacity of water storage tank is technically and economically better than supporting a photovoltaic water pumping systems with another energy source or extra storage device.