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This paper aims to provide a flexible polyurethane (PU) film with visible light trapping ability, photothermal conversion and energy storage performance by covalently bonded a visible light absorbing dye into the polymer through copolymerization.

For this target solution copolymerization of diphenyl-methane-diisocyanate (MDI), poly(1,4-butylene adipate) (PBA2000), polyethylene glycol (PEG) of different molecular weight, self-made dye, 1,4-butanediol (BuOH) was carried out in a flame-dried flask under an inert nitrogen (N₂) atmosphere. First, an isocyanate-terminated prepolymer of dried PEG, MDI and PBA2000 was prepared in dimethylformamide and stirred for 1 h at 35°C. Then, self-made dye and 1, 4-butanediol (BuOH) were added and heated at 85°C for 3 h to get photothermal conversion polyurethane (PTPU) solution. Allowed the solution to dry at room temperature for seven days and then at 65°C for 12 h to get PTPU films.

The flexible PU films with photothermal conversion and energy storage performances were successfully synthesized and the functional films presented both excellent energy storage and mechanical property when the molecular weight of PEG was in the range of 6,000∼10,000.

The materials that were used in this research paper had a reasonably low cost. Also, the procedures for the synthesis of dye and polymers were extremely easy because there was no need for high pressure or temperature and no dangerous solvents were used.

The photothermal conversion property and mechanical performance of the synthesized flexible PU films were characterized. The results have proved that these films were soft and elastic, and have certain photothermal conversion and energy storage ability, thus can be used in the surface finishing of special fabric and leather.

Visible light trapping photothermal conversion PU flexible film with energy storage capability was prepared for the first time.

This is a preliminary study on the modal split of reducing environmental contaminants to a minimum. In this paper, we focus on NO_x as a typical air pollutant and make clear the structure of energy flow with regard to freight transport using input‐output analysis. Then we present a mathematical model for the optimal modal split considering the input‐output structure of energy flow. The goal of this model is to minimize NO_x which is emitted in the processes of freight transport, energy transport and energy production subject to maintaining the status quo of freight volume transported in Japan. This model is applied to the actual freight transport problem in Japan and the validity of this model is evaluated. As the result of that, we could suggest a policy of the modal shift, which can reduce the volume of NO_x emissions in the transportation sector by approximately 30 per cent compared to the current circumstances in Japan.

The nuclear battery technology depends on the spontaneous decay of the atomic nuclei of radioactive isotopes to generate electricity. One of the merits of a nuclear battery is its high-energy density, which can be around ten times higher than that of hydrogen fuel cells and a thousand times more than that of an electrochemical battery. A nuclear battery has an extremely long life and low maintenance and running costs coupled with applications in remote and hostile environmental environments. The rise of silicon technology has intensified research activities in the area of nuclear batteries. The paper aims to present a general overview of a nuclear battery.

This paper presents a general overview of a nuclear battery and will significantly reduce reliance on non-renewable energy source. The requirement for long-lived power supplies have necessitated the pragmatic shift toward the realization of cleaner, safer and renewable energy sources.

Nuclear battery is a safe enabling technology for many applications including military and commercial applications. They have very long operating life under harsh environmental conditions. These cells demonstrate high potential for use in low power applications under a broad range of temperatures.

The nuclear battery technology has been receiving considerable in-depth research for applications that require long-life power sources.

This paper aims to propose a bidirectional hidden converter (BHC)-based three-phase DC–AC conversion for energy storage application. BHC is the new concept to vary an energy storage device voltage into wide range. Hidden converter power loss and power rating are reduced by using zero-sequence injection-based carrier-based pulse-width modulation (CBPWM) strategy.

By using this control strategy, a BHC processes only little amount of power during double-stage conversion, mostly during direct or single-stage conversion of the three-phase three-port converter (TPTPC) only processing the maximum power.

TPTPC consists of two sets of positive group switches for inversion process, one set of switches is regular inverter switches called vertical positive group switches, and the second set is anti-series switches, which are horizontally connected for direct or single-stage conversion.

Characteristics, principles and implementations of proposed DC–AC 3Ø conversion system and its PWM strategy are analyzed. Through experimental outputs, the effectiveness and viability of the proposed solutions are validated.

The purpose of this paper is to present the design of a piezoelectric vibration energy generator with a power conditioning circuit to power a wireless sensor node. Frequency and voltage characterization of the piezoelectric energy harvester is performed. A single-stage AC–DC power converter that integrates the rectification and boosting circuit is designed, simulated and implemented in hardware.

The designed power conditioning circuit incorporates bridgeless boost rectification, a lithium ion battery as an energy storage unit and voltage regulation to extract maximum power from PZT-5H and to attain higher efficiency. The sensor node is modelled in active and sleep states on the basis of the power consumption. Dynamic modelling of the lithium ion battery with its state of charging and discharging is analysed.

The test result shows that the energy harvester produces a maximum power of 65.9 mW at the resonant frequency of 21.4 Hz. The designed circuit will operate even at a minimum input voltage of 0.5 V. The output from the harvester is rectified, boosted to a 7-V DC output and regulated to 3.3 V to the power C_Mote wireless sensor node. The conversion efficiency of the circuit is improved to 70.03 per cent with a reduced loss of 19.76 mW.

The performance of the energy harvester and the single-stage power conditioning circuit is analysed. Further, the design and implementation of the proposed circuit lead to an improved conversion efficiency of 70.03 per cent with a reduced loss of 19.76 mW. The vibration energy harvester is integrated with a power conditioning circuit to power a wireless sensor node C_Mote. The piezoelectric vibration energy harvester is implemented in real time to power C_Mote.

To analyze the operating performance of a fuzzy logic control (FLC) based solar energy conversion modular system controlled by a digital signal processor (DSP) microcontroller.

A range of published works relevant to the solar energy conversion modular systems are evaluated and their limitations are indicated in the first section of the paper. The circuit diagram of the panel‐boost converter system is described in the second section. In the third section, a neural network model is suggested for the photovoltaic panel and the model is created in the MATLAB/SIMULINK and then combined with other blocks existing in the system. The design of the FLC method is described in section 4. The simulation and experimental results corresponding to the control of the duty‐cycle of the converter to set the operating point of the solar panel at the maximum power point (MPP) are given in sections 5 and 6, respectively. Section 7, summarizes the results and conclusions of the study.

The paper suggests a simple dc‐dc boost converter controlled by FLC method. The proposed converter model can be used to obtain maximum power from a photovoltaic panel.

In preparing this paper, the resources books existing in the library of our university and the resources relative to the solar energy conversion and FLC published in English language and reachable through the internet were researched.

The paper suggests a neural network model for a solar panel, which can be used in the simulation of the solar energy panel‐boost converter system. The solar energy panel‐boost converter system proposed in this study can be used by the researchers who are working in the solar energy conversion area.

The suggestion of a neural network model for a solar panel and creation of this model in the MATLAB/SIMULINK environment provides researchers to simulate and to analyze the performance of the solar energy panel‐boost converter system using the MATLAB/SIMULINK simulation program. In addition, since the control approach proposed in this paper does not require the information on temperature and solar irradiance that affect the maximum output power, can effectively find the MPP of the solar panel.

Solar selective coatings are designed and formulated for effective collection and retention of solar energy. Several types of coatings can be utilized for economical collection of solar energy, the most common and simplest will be ordinary non‐glass, heat resistant black paint. The coatings may be moderately selective or non‐selective absorbers, consisting of organic or inorganic matt black paints. These are easiest to apply and the least expensive of all collector coatings. In this category other types are ceramic and organic enamels and chemical or electrochemical metal conversion coatings. An impending energy crisis has already aroused interest and scientific pursuit in the field. An analysis of the state‐of‐the‐art in solar selective coatings was felt necessary at this time.

The purpose of this paper is to use numerical simulations to investigate the energy conversion performance and the flow and temperature structures inside horizontal tubes connected to a vertical manifold channel.

The simulations are performed for different flow rates and inlet temperatures using CFD.

In both the “flowing wind mode” and “upwind mode,” the inlet velocity is not infinitely small under the influence of natural convection; however, such small inlet velocities cannot be achieved in practice and are of no practical significance. In the “flowing wind mode,” the appropriate velocity for achieving high efficiency is 0.01-0.02 m/s. In the “upwind mode,” the appropriate velocity for obtaining high efficiency is 0.1-0.2 m/s. A high inlet temperature can lead to high efficiency; therefore, a large temperature difference and a small flow can be used in actual designs.

The energy conversion performance and flow structures inside evacuated tubular collectors were investigated using CFD for different operating conditions, notably in the “following wind mode” and the “upwind mode.”

The aim of this study was to first establish foundational algebraic expressions that parametrically describe any advanced dual-energy storage–propulsion–power system (DESPPS) and then proceed to declare the array of fundamental independent variables necessary for the sizing and optimisation of such systems. Upon procurement of a pre-design-level integrated aircraft performance model and the subsequent verification against previously published high-end low-fidelity generated results, opportunity was taken in formulating a set of battery-based DESPPS related design axioms and sizing heuristics.

Derivation of algebraic expressions related to describing DESPPS architectures are based on first principles. Integrated performance modelling by way of full analytical fractional change transformations anchored according to a previously published Energy Specific Air Range (ESAR) figure-of-merit originally derived using the Breguet–Coffin differential equation for vehicular efficiency. Weights prediction of sub-systems that constitute the entire aircraft including DESPPS constituents emphasises an analytical foundation with minimal implementation of linear correlation factors or coefficients of proportionality. An iterative maximum take-off weight build-up algorithm emphasising expedient and stable convergence was fashioned. All prediction methods pertaining to integrated performance were verified according to previously published battery-based DESPPS results utilising high-end low-fidelity methods.

For all types of DESPPS, two new fundamental independent non-dimensional variables were declared: the Supplied Power Ratio (related to converted power afforded by each energy carrier); and, the Activation Ratio (describing the relative nature of utilisation with respect to time afforded by the motive power device associated with each energy source). For a given set of standalone sub-system energy conversion efficiencies, the parametric descriptor of degree-of-hybridisation (DoH) for Power was found to be solely a function of the Supplied Power Ratio, whereas in contrast, the DoH for Energy was found to be a more complex synthetic function described by comingling of Supplied Power Ratio and the Activation Ratio. Upon examination of the integrated aircraft performance model derived in this treatise, for purposes of investigating CO₂-emissions reduction potential for battery-based DESPPS using kerosene as one of the energy sources, one salient observation was maximising the ESAR figure-of-merit is not an appropriate objective or intermediary function for future optimisation work. It was found maximising block fuel reduction through the use of maximum ESAR would lead to ever diminishing design ranges and curtailment of the payload-range working capacity of the aircraft.

Opportunity is now given to design and optimise aircraft utilising any type of DESPPS architecture. It was established that designing for battery-based DESPPS aircraft can be achieved effectively in a two-stage process that may not require aircraft morphologies more exotic than the so-called “wing-and-tube”. Firstly, a suitably projected state-of-the-art aircraft with solely advanced gas-turbine technology for the propulsion and power system needs to be produced. Thereafter, a revised version of this baseline projected aircraft now using DESPPS architecture should be conceived. A recommendation related to CO₂-emissions reduction potential for battery-based DESPPS using kerosene as one of the energy sources is that during optimisation work the multi-objective formulation should comprise at least two functions: block fuel and operating economics. In all instances, it was advised that the objective function of block fuel should be tempered by an equality constraint of ESAR parity with the baseline projected aircraft using gas-turbine only technology.

A complete, unified analytical description of DESPPS that is universally applicable to any type of energy carrier has been derived and verified for battery-based dual-energy systems. Correspondingly, a set of aircraft design axioms and sizing heuristics relevant to battery-based DESPPS have been presented.

The way and manner in which energy is produced is known to have a significant impact on emissions. For this reason, the UK government has sought to enhance the efficiency of energy production/conversion by focusing on a number of energy production approaches, including Combined Heat and Power (CHP). The purpose of this paper is to describe a practical approach for assessing the feasibility of CHP.

The authors provide an overview of Combined Heat and Power (CHP); describe a new and easy‐to‐implement feasibility and optimisation model to aid in the installation of CHP; and discuss the practical feasibility issues of CHP through an analysis of existing case studies using the proposed model. The modelling utilises regression models which are created using historical data obtained from public sources.

Compared against alternatives, the model is shown to be particularly useful, as its functionality is embedded in resource‐intensive prime mover specifications obtained from seven real industrial cases.

The need for such a practical and easy‐to‐use model is driven by the existence of numerous models, which are mainly complex and not necessarily “user‐friendly”. The proposed model is set to provide a practical and user‐friendly model for CHP appraisal that is easy to understand and assess in terms of prime movers such as capital cost, payback, annual financial and CO₂ savings.