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The utilization of a hybrid energy system (combined solar water heater (SWH) and an air source heat pump (ASHP) water heater) can result in over 80% reduction in the electrical energy consumed as the system is capable to operate with an energy factor of above 4.0. A major challenge is to develop credible methodology or mathematical model to predict energy savings. The research focused on the design and installation of a hybrid energy system and a data acquisition system to monitor its performance. The average weekday volume of hot water consumed, thermal energy gained by water in the tank of the air source heat pump (ASHP) water heater, electrical energy consumed, and the COP were 225.03 L, 5.25 kWh, 1.52 kWh, and 3.50. The average weekday global solar radiation, ambient temperature, solar fraction of the solar water heater (SWH) and the energy factor of the hybrid energy system were 579.67 W/m2, 23.58°C, 0.52, and 4.02, respectively. A multiple linear regression model was developed to predict the energy factor of the hybrid energy system. Both the modelled and validated results showed very good determination coefficients of 0.952 and 0.935, with the trained and validated dataset. Hence, by employing both multiple linear regression model and a multiple 2D contour plot simulation, the energy factor and the variation of the input parameters can be accurately determined. The developed model can help homeowners, energy service companies, and policy makers to appreciate and confidently support the rollout of the technology for sanitary water heating.

To describe the influence of design parameters on energy consumption, a structured information description framework oriented to energy-saving design of machinery equipment is proposed, which is composed of two sub-models: the energy consumption description model, and the design – energy consumption information correlation model. Firstly, the energy consumption composition of running procedures is analysed and the energy balance equations based on the kinetic energy theorem are built. Furthermore, a structured energy consumption description model – energy breakthrough structure (EBS) – is proposed; EBS is composed of some interrelated energy factors, and the energy factors are divided into two types: the energy element (EE) and the energy control unit (EC), where EE is the basic energy consumption description unit, and EC is the upper lower of energy factor, which is determined by the lower-level EE and EC. The relationships among energy factors can be divided into three types: Or, And, Proportional And; ...

This paper analyses the carbon dioxide emissions caused by industrial energy consumption of Tianjin from 2005 to 2012. The carbon emissions decomposition illustrated that the scale of production factor played a major role in the growth of Tianjin industrial carbon emissions and the average contribution of carbon emissions is up to 220.8975% in the statistical period; the intensity of energy factor played an important role in slowing down the growth of industrial carbon dioxide emissions. The average contribution of carbon emissions was −136.1994% in the statistical period. The prediction model based on carbon emissions data from industrial energy consumption from 2003 to 2012 reached a high accuracy, with an average error of 1.78% for stochastic impacts by regression on population, affluence, and technology (STIRPAT) model, 2.41% for the Logistic regression model and an average error of 1.54% for the grey model. This research can contribute to predict the carbon emission and through it some suggestions ca...

A yield increase in the distillation step reveals a promising way to guarantee technical and economic feasibility for small-scale ethanol production (SSEP), up to 30 L · h−1. The objective of this study is to assess a differentiated distiller, a hybrid composition involving a Vigreux column and a packing (Raschig rings) column in the stripping and rectifying sections, respectively. To evaluate the distiller, seven tests were performed in a continuous operation system. The feed and vaporization rates were varied so that their influence on the operational performance of the distiller could be measured. Specifically, the ethanol concentration in the distillate and bottom products, the operational capacity, and the energy factor were measured. The results prove the technical feasibility of the hybrid distiller, and the application of the hybrid distiller in small-scale distilleries is promising. To improve the distillation step, construction of a pilot-scale column is recommended.

A number of different displacement-based design (DBD) methods have been put forward over the past decade in order to address shortcomings with current force-based design approaches. Considerable progress has been made in developing DBD procedures for a wide variety of structural typologies. However, the new displacement based design approaches are considerably more time-consuming for simple low- and medium-rise structures than quick force-based design methods such as the equivalent lateral force method. In this work, a new simplified displacement-based design approach, referred to as the energy-factor method, is described and applied to a number of case-study wall structures. The results of the method are compared with those obtained from the equivalent force-based design approach and the Direct DBD method. The performance of the method is then gauged through a series of nonlinear time-history analyses using spectrum-compatible accelerograms. The results indicate that the simple energy-factor method could...

SummaryThis work gives answer to an important questian usually asked in induction heating designs: given a coil and a workpiece. which are the optimal: parameters (frequency and coil-workpiece geometry) to heat this system? TO answer this question a new parameter called Energy Factor (EF) is defined in electromagnetic and in circuit terms. This factor indicates the transfer energy efficiency between two systems (Fig I), in the case of an induction heating system, between the coil and Me load.

It is shown that energy flows along a dislocation as it moves in translation, and it is demonstrated that there is a simple connection between this energy flow and the change of dislocation energy factor with change in dislocation orientation. With the dislocation in directions of high symmetry for which explicit solutions for the stresses and the energy factors are possible, the derivatives of energy factor with respect to dislocation orientation can also be calculated explicitly. With both energy factors and their derivatives known for a number of discrete orientations, it may be possible to construct reliable continuous plots of energy factor versus orientations.