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This paper presents a degradation testing of a lithium-ion battery developed using real world drive cycles obtained from an electric vehicle (EV). For this, a data logger was installed in the EV, and real world drive cycle data were collected. The EV battery system consists of 3 lithium-ion battery packs with a total of 20 battery modules in series. Each module contains 6 series by 49 parallel lithium-ion cells. The vehicle was driven in the province of Ontario, Canada, and several drive cycles were recorded over a 3-month period. However, only 4 drive cycles with statistical analysis are reported in this paper. The reported drive cycles consist of different modes: acceleration, constant speed, and deceleration in both highway and city driving at −6°C, 2°C, 10°C, and 23°C ambient temperatures with all accessories on. Additionally, individual cell characterization was conducted using a C/25 (0.8A) charge-discharge cycle and hybrid pulse power characterization (HPPC). The Thevenin battery model was constructed in MATLAB along with an empirical degradation model and validated in terms of voltage and SOC for all drive cycles reported. The presented model closely estimated the profiles observed in the experimental data. Data collected from the drive cycles showed that a 4.6% capacity fade occurred over the 3 months of driving. The empirical degradation model was fitted to these data, and an extrapolation estimated that 20% capacity fade would occur after 900 daily drive cycles. [ABSTRACT FROM AUTHOR]

SUMMARY In this paper, a novel integrated solar photovoltaic thermal absorption desalination system for freshwater and cooling production is proposed and analyzed thermodynamically. Ammonia-water pair is considered as a working fluid for the absorption system. Effect of average solar radiation for different months, time period of solar radiation availability in Abu Dhabi, salinity of seawater, and temperature of the seawater on energetic and exergetic COPs, production rate of freshwater, and overall performance of the system are investigated under different operating conditions. It is found that energetic and exergetic COPs, production rate of freshwater, energetic and exergetic utilization factors, and performance ratios vary greatly from one month to another because of the dynamic variation in solar radiation and its time of availability. The highest amount of freshwater is produced in the month of July as calculated to be 152 kg/h for a collector area of 100 m2 and solar power of 4.8 kW. The highest energetic and exergetic COPs and utilization factors are also obtained for the month of July. Moreover, the highest performance ratio is found to be 0.056 as obtained in the month of July when solar radiation intensity is highest as available for more than half of a day. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

SUMMARY This paper performs a thermodynamic analysis of a modified dual photo-electrochemical cell for water electrolysis, previously developed by Grätzel. In a typical Grätzel cell, a semi-transparent photo-electrode is used in conjunction with a dye photo-sensitized cell to generate a bias voltage necessary to overcome the inherent over-potentials caused by irreversibilities within the cell. The modified method implements hybrid photo-catalysis instead of heterogeneous catalysis. In the hybrid photo-catalysis approach, both homogeneous and heterogeneous photo-catalysts are used to enhance the speed of the water splitting reaction and to widen the portion of the solar radiation spectrum for the process. The dual cell consists of two tandem units. The first unit is a photo-electrolysis cell exposed to solar radiation (at both cathodic and anodic sides) via a transparent window, whereas the second unit is a dye-sensitized solar cell, which assists the photo-electrolysis cell. In the cathodic solution, there are dissolved Brewer-type supra-molecular complexes for photo-catalytic water reduction to generate hydrogen. They absorb solar radiation in the upper visible spectrum and dislocate multiple electrons at the active center. The complexes accept electrons donated from a GaP-based semi-transparent photo-cathode. The remaining un-absorbed radiation (mainly in the infrared range) crosses the semitransparent counter-electrode and the back glass. It is absorbed by a solar thermal collector for enhancing the solar radiation utilization by co-generating low-grade heat. The tandem cell with hybrid photo-catalysis has promising potential of improved solar radiation utilization. This paper analyzes the system efficiency and shows that 4% energy efficiency can be obtained for hydrogen generation. About 20% of the incident solar spectrum can be captured by the cell and used for hydrogen generation. Around 60% of solar radiation is recovered in the form of heat on a flat plate solar thermal collector placed behind the cell. The influence of catalyst concentration and pH also is studied. The device forms a four-gap solar absorber system, which is coupled to a cogeneration sub-system for heating, so the solar energy utilization is maximized. The four-gap system absorbs photons at 1.6, 2.1, 2.3, and 2.7 eV and generates five reversible potentials of 0.42, 0.9, 1.6, 2.1, and 2.3 V. Based on the predicted results, the reaction rate appears to be enhanced with respect to other solar electrolysis cells (such as photo-electrolyzers and a dual photo-electrochemical cell) because homogeneous catalysis enhances the electrode kinetics. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

SUMMARY Thermal management systems (TMS) are one of the key components of electric and hybrid electric vehicles to achieve high vehicle efficiency and performance under all operating conditions. Current improvements in electric battery technology allow vehicles to have relatively long ranges, fast acceleration, and long life while keeping low-maintenance costs and considerably lower emissions. However, the vehicle performance is significantly affected by the battery operating conditions. Moreover, the cell life cycle, safety, and possibility of thermal runaway significantly depend on peak temperature rise and temperature uniformity of the battery. Therefore, various TMSs are created to keep batteries within ideal operating ranges. In this article, three different TMS systems-passive cabin cooling (via air), active moderate liquid circulation (via refrigerant), and active liquid circulation (via refrigerant and coolant)-are analyzed and compared with electric and hybrid electric vehicles. A second law analysis is used to examine the areas of low exergy efficiency in each system and minimize the entropy generation based on the system configuration. Moreover, TMS systems are compared on the basis of battery temperature increase and temperature uniformity. Various parametric studies are conducted to compare the TMS in different ambient and operating conditions. On the basis of the analysis, the active liquid circulation (via refrigerant and coolant) is determined to have the lowest battery temperature increase (3.9 °C in 30 min) and most cell temperature uniformity (2.5 °C median) as well as the lowest entropy generation rate (0.0121 W/K) among the compared systems. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

SUMMARY In this paper, the exergy interactions, environmental impact in terms of CO2 mitigation, and the economics of small-capacity concentrated solar power-driven heat engines for power and heat generation are analysed for residential applications. Starting from a base case study that assumes mass production in Ontario, it is shown that the investment in such a system, making use of a heat engine and having 9 m2 of aperture area, could be about CN$10 000 for a peak electrical efficiency of 18% and thermal efficiency of 75%. The average CO2 mitigation due to combined savings in electricity and heat is ∼0.3 kgCO2 kWh−1, a figure 3-4 times larger than for photovoltaic panels. If 25% government subsidy to the investment is provided, the payback period becomes 21.6 years. Additionally, if the financing benefits from a feed-in-tariff program (at 25% electrical sell-back to the grid) and deductions from CO2 tax are realized, then the payback time drops to 11.3 years. These results are obtained for a conservative scenario of 5.5% annual incremental increase in energy price. For the moderate consideration of all factors, it is shown that within the financial savings over the entire lifecycle, 7% are due to carbon tax, 30% are due to electrical production and the largest amount, 63%, is the result of reducing the natural gas heating capacity with solar heating from the proposed system. Copyright © 2011 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

SUMMARY The present study deals with a comprehensive thermodynamic modeling of a combined heat and power (CHP) system in a paper mill, which provides 50 MW of electric power and 100 ton h−1 saturated steam at 13 bars. This CHP plant is composed of air compressor, combustion chamber (CC), Air Preheater, Gas Turbine (GT) and a Heat Recovery Heat Exchanger. The design parameters of this cycle are compressor pressure ratio ( rAC), compressor isentropic efficiency ( ηAC), GT isentropic efficiency ( ηGT), CC inlet temperature ( T3), and turbine inlet temperature ( T4). In the multi-objective optimization three objective functions, including CHP exergy efficiency, total cost rate of the system products, and CO2 emission of the whole plant, are considered. The exergoenvironmental objective function is minimized whereas power plant exergy efficiency is maximized using a Genetic algorithm. To have a good insight into this study, a sensitivity analysis of the results to the interest rate as well as fuel cost is performed. The results show that at the lower exergetic efficiency, in which the weight of exergoenvironmental objective is higher, the sensitivity of the optimal solutions to the fuel cost is much higher than the location of the Pareto Frontier with the lower weight of exergoenvironmental objective. In addition, with increasing exergy efficiency, the purchase cost of equipment in the plant is increased as the cost rate of the plant increases. Copyright © 2010 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

In this paper, a comprehensive study on corn-based ethanol in a Canadian context is conducted, which uses the most reliable and up to date data, considers realistic assumptions, and applies sound methodology to provide a basis for developing future scenarios for corn-based ethanol and compared the results with the conventional fuel, such as gasoline. It is estimated that the net energy value (NEV), defined as the energy content of a liter of ethanol minus the total energy use to produce a liter of ethanol, is 9.6 MJ L (LHV), when co-products energy credits are not considered. In addition, a comparison of life cycle energy use for corn-based ethanol and gasoline reveals that the life cycle energy use to produce a liter of ethanol is considerably less than the life cycle energy use to produce a liter of gasoline. Furthermore, a comparison of life cycle greenhouse gas (GHG) emissions for corn-based ethanol and gasoline reveals that the life cycle GHG emissions released per liter of ethanol produced is an order of magnitude lesser than the life cycle GHG emissions released per liter of gasoline produced, when GHG emissions displaced by ethanol co-products are considered in the estimation. Finally, a comparison of our results in terms of net fossil fuel input, net fossil fuel ratio and GHG emissions is carried out with the results obtained from the ERG biofuel analysis meta-model (EBAMM) to reflect both Canadian and US perspectives. Copyright © 2010 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

In this paper, the development of new Fourier-Reynolds correlations for determining the cooling process parameters of products subject toair cooling, in terms of the half cooling times and seven-eighths cooling times is presented. The experimental data were taken from the author's previous work, processed and used in the development of new Fourier- Reynolds correlations and diagrams. These Fourier-Reynolds correlations are FoH = 42.465Re-0.54426 and Fos = 125.21Re- 0.53913 for half cooling times and seven-eighths cooling times, respectively. The results of this study indicate that there is a strong relationship between the Fourier and Reynolds numbers, and the Fourier-Reynolds correlations and diagrams are simple and effective tools for determining the cooling process parameters for such objects cooled in air flows. It is believed that these could be beneficial to the refrigeration industry. [ABSTRACT FROM AUTHOR]

Understanding of the role of energy use at the national level requires the understanding of the relationship of energy use to economic activity and social well-being. Gross domestic product (GDP) measures the value of goods and services produced in a country in one year. There is a close relationship between energy supply, energy consumption,and GDP, which indicates the economic development of a country. The living standard of a country is often measured by the per capita GDP.This article presents the evaluations and future projections of energy and energy resources of the Organization for Economic Cooperation and Development (OECD). The total primary energy supply, total final energy consumption, and energy intensities for supply and consumptionare analysed. The energy data for all OECD countries are presented and analyses of the differences in energy and GDP ratios are conductedat an aggregate level by examining differences in the factors that affect the energy intensities. To provide accurate projections for thefuture, new correlations are developed between average GDP, total primary energy supply, total final consumption, total per capita primary energy supply, total per capita final consumption and total OECD population. [ABSTRACT FROM AUTHOR]