• AIP Publishing
• AVS: Science & Technology of Materials, Interfaces, and Processing
• Acoustical Society of America
• American Association of Physicists in Medicine
• American Association of Physics Teachers
• American Crystallographic Association, Inc.
• Chinese Physical Society
• Chinese Society of Theoretical and Applied Mechanics
• Laser Institute of America
• The Society of Rheology

Journal of Renewable and Sustainable Energy is an online-only journal dedicated to publishing significant advances covering all aspects of renewable and sustainable energy relevant to the physical science and engineering communities. As a web-based journal with rapid publication time, Journal of Renewable and Sustainable Energy is responsive to the many new developments expected in these fields. The interdisciplinary approach of the publication ensures that the editors draw from authors from around the world across a diverse range of active and expanding fields. The journal is published online only on a bi-monthly basis (6 issues per year).

Editor's Picks

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  Study on the temperature compensation technology of air-powered engine

  dx.doi.org/10.1063/1.4915294

  First, the principle of the temperature drop in the air-powered engine (APE) is studied in this paper. The thermodynamic model of the APE and the calculation model for equivalent air temperatures in critical locations of the APE are proposed. Second, through the calculation by the models above, the temperature drop of the APE causes the ice blocking to influence the APE working negatively. And it is a particular problem that conventional gasoline engines will not meet. To solve the ice blocking problem without consuming additional energy out of the APE system, a heat exchange structure for the APE is designed to compensate the drop temperature and make sure the APE work efficiently. To verify the APE works in a good temperature distribution situation, some simulations are done, it is shown that the APE with the heat exchange structure works better in temperature distribution and ice blocking prevention. In addition to this, the results of simulation are verified by experiments. In conclusion, the APE with the heat exchange structure can avoid the ice blocking problem. Besides, it can help improve the APE's working efficiency by about 30%. The study provides a theoretical basis for further research on the principle of the temperature drop and heat exchange in the APE.

• 

  Sulphonate anchored hemicyanine dyes for dye solar cell: A study on dipole moment and polarity

  dx.doi.org/10.1063/1.4915519

  The effect of the molecular architecture of dye on the performance of a hemicyanine based dye sensitized solar cell (DSSC) has been studied using theoretical and experimental tools. These dyes were utilized as sensitizers in DSSC and then later were characterized using various techniques like I-V, impedance, electron transfer kinetics, dielectrics, and Tafel polarization in order to study the photovoltaic performance. The dye having a p-OH group (INS 1) exhibited very good photon to electricity conversion efficiency (3%) along with good fill factor while the dye having a p-OMe group (INS 2) lagged behind in performance. The substituent effect was studied theoretically as well as experimentally emphasizing the dipole moment of the dye in various directions. Theoretical investigation reveals that the presence of a p–OH group in the donor unit enhances the dipole moment of the molecule in comparison to a p-OMe group, thereby imparting longer lifetime of excited state leading to better charge transfer at the TiO2/dye interface.

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  Application of an ice thermal energy storage system as ways of energy management in a multi-functional building

  dx.doi.org/10.1063/1.4913646

  Peak-hour tariff typically troubles commercial office buildings in hot and humid climates where cooling demands are high during summer. Because the local power company rate structure strongly favors the practice of load shift and conversely penalizes peak load demand during peak hours, a multi-functional office building in Taipei seeks to reduce its cooling cost by ways of an ice thermal energy storage system in which harvested ice is stored during cheaper off-peak hours and thawing the storage medium during peak hours. The system uses partial storage approach to satisfy off-peak cooling demand while peak-hour cooling burden is relieved by chilled water built the previous night. Two screw chillers would be integrated with each other for the implementation to allow feeding chill water to the air-handler coils while producing ice for storage at the same time. The refrigeration cycle of water chilling operates under two modes, the ice mode for thermal storage, and the chill water mode for instantaneous air cooling. Super-cooled air from melted ice-water makes humidity levels to be lower than conditioned with conventional systems, as well as load shift incentives. Cool air is introduced to variable air volume terminal boxes and is mixed with induced plenum air to bypass any reheat, yielding additional saving.

• 

  Research on energy extraction characteristics of an adaptive deformation oscillating-wing

  dx.doi.org/10.1063/1.4913957

  Oscillating foil machines represent a type of flow energy harvesters which perform pitching and plunging motions simultaneously to harness the energy from incoming stream. In this paper, a new adaptive deformation oscillating wing was proposed and the theoretical performance of such a concept was studied here through unsteady two-dimensional simulations using an in-house developed computational fluid dynamics code. During operation, the proposed oscillating foil whose initial shape is symmetric can be deformed into a cambered foil, which aims to produce large lift force. Our numerical results suggest that the power efficiency of the proposed oscillating foil can be about 16.1% higher than the conventional oscillating foil without deformation. In addition, the effects of the maximum bending displacement and effective angle of attack on the efficiency of proposed oscillating foil were also discussed in this work.

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  Models for daily global solar radiation for the Caribbean island of Trinidad

  dx.doi.org/10.1063/1.4909539

  In this study, calibration and validation data sets from 2001 to 2005 and 2006 to 2010, respectively, were used to develop various Angström-Prescott models: A five-year model and five-year dry and wet seasonal models to calculate monthly average daily global solar radiation on a horizontal surface and twelve monthly models to estimate average daily global solar radiation on a horizontal surface. Also, ten yearly models were developed for each year in the period 2001–2010. The regression coefficients for the five-year, dry season, and wet season models were found to be (0.21, 0.38), (0.21, 0.38), and (0.27, 0.28), respectively. For the twelve monthly models, and varied over the ranges 0.19–0.37 and 0.14–0.42, respectively. For the ten yearly models, and varied over the ranges 0.15–0.31 and 0.22–0.48, respectively. The regression coefficients of the twelve monthly models yielded a linear relationship between and over a one-year time scale. Similarly, the ten yearly models also yielded a linear relationship between and over a ten-year time scale. For all the models, measured and calculated daily global solar radiation were compared by calculating the mean bias error, mean percentage error, root mean square error, correlation coefficient, Nash-Sutcliffe efficiency, and p-values based on t-statistics. Good agreement was found between the measured and calculated values and hence these models can be used in Trinidad. The single five-year model was found to be adequate in modelling the dry and wet seasons. Using the full data set, 2001–2010, the average daily global solar radiation, average total global solar radiation, average daily number of sunshine hours, and average total number of sunshine hours were determined to be MJ m⁻² day⁻¹, GJ m⁻², h day⁻¹, and h, respectively, for the dry season; MJ m⁻² day⁻¹, GJ m⁻², h day⁻¹, and h, respectively, for the wet season; and MJ m⁻² day⁻¹, GJ m⁻², h day⁻¹, and h, respectively, for the whole year.