Search

The paper deals with a detailed study on the optimal sizing of a solar hybrid car, based on a longitudinal vehicle dynamic model and considering energy flows, weight and costs. The model describes the effects of solar panels area and position, vehicle dimensions and propulsion system components on vehicle performance, weight, fuel savings and costs. It is shown that significant fuel savings can be achieved for intermittent use with limited average power, and that economic feasibility could be achieved in next future, considering the expected trends in costs and prices.

After a general overview of Hybrid Power Plants (HPP) and Compressed Air Energy Storage (CAES), the authors present a thermo-economic model for the simulation and optimization of a HPP consisting of a wind turbine coupled with CAES. In the proposed scheme, during periods of excess power production, atmospheric air is compressed in a multistage compressor and cooled; when there is power demand, the compressed air is heated in multiple expansion stages using the stored heat and conventional thermal sources. Such plants can offer significant benefits in terms of flexibility in matching a fluctuating power demand, particularly when renewable sources, characterized by high and often unpredictable variability, are utilized. The possible advantages in terms of energy and cost savings with respect to other solutions must be carefully assessed, critically depending on performance and efficiencies of each sub-system, most of them operating in transient and off-design conditions. To this purpose, a thermodynamic model composed of several sub-systems describing wind turbine, multi-stage compressor, intercooler, aftercooler, heat recovery system, compressed air storage and turbine has been developed in Matlab/Simulink® environment. In the paper, several scenarios are compared by simulation and optimization analysis and a parametric study of the plant performance with respect to the main design variables is presented.

In this study, the landfill of Palermo, is investigated as a potential source of the unusual methane concentrations found in the urban context. The source for these pollution episodes is identified by means of a simple heuristic method. A cross-correlation analysis between wind data and methane concentration levels is also used to confirm the hypotheses formulated. Doppler Sound Detection And Ranging (SODAR) measurements are used to investigate the air masses dynamics at the landfill, in order to better support the adopted assumptions. This interpretative method can be adopted in the first assessment stages of the environmental site performance in order to single out the candidate pollution sources in urban areas, before any analytical computation takes place. In this sense, the method is intended as a viable tool in decision-making processes where in local administrations are currently involved in the selection of sustainable policies for the correct management of the territory. Copyright © 2009 Inderscience Enterprises Ltd.