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A new concept of a system for Combined Heat and Power generation is presented. The concept is based on hybrid use of two renewable energy sources, direct solar (thermodynamic solar) and biomass (indirect solar energy). Biomass combustion is conducted using a fluidized bed combustor. A second source of energy, given by the direct irradiation of the bed with a concentrated solar radiation, is integrated in the same system, using the fluidized bed as solar receiver. A Stirling engine converts heat into mechanical power. A Scheffler type mirror is adopted to allow irradiation of the system in a fixed focal point. Advantages of the proposed solution are illustrated and some preliminary results on the performance of the system, obtained with a simple model, are presented. The principal improvements with respect to existing systems of similar size and primary energy source are illustrated. The most important are the enhanced heat transfer processes that are realized with the help of the fluidized bed, and the possibility of continuous cogeneration during the day. Different working conditions are considered to estimate the contribution given by the burning of fuel, in presence as well as in absence of sun irradiation (as during the night). The distribution of energy shares among the different flux contributes is reported versus the amount of biomass burned per unit time. The results clearly demonstrate the advantage of coupling, in the same system, two sources for heat generation, thus maintaining the option of producing electricity without the supply of biomass fuel.

ON 16 NOVEMBER 2000, the final report of the World Commission on Dams (WCD) was launched in London, in the presence of South Africa’s former president Nelson Mandela. This represented a remarkable milestone in the history of dam policy and politics. During its two-year existence, WCD had conducted the most extensive review of research and evidence regarding the planning, impacts, and management of large dams. It had engaged with numerous stakeholders around the globe. It also made comprehensive recommendations about how to improve dam planning and management.

Coordinate pulsewidth modulation is considered for the control of power switches of matrix and two-component direct frequency converters (DFC) in ac drive systems. The synthesis of modulating signals yielding the specified output voltages and sinusoidal grid currents for converters with no intermediate smoothing filter is discussed. Simulation of DFC operation with an RLE load and an asynchronous motor is undertaken.

When the degradation growth of a unit depends only on its age, a widely accepted model to describe the degradation phenomenon is the non-homogeneous gamma process, which proved to be suitable to model such degradation phenomena as wear, fatigue, corrosion, crack growth, erosion, and consumption. In this paper, a Bayesian inferential procedure using the Markov Chain Monte Carlo technique is proposed for the non-homogeneous gamma process with power-law shape function. All the process parameters are left to be assessed, and prior information is formalized on some quantities having a "physical" meaning. Both vague and informative priors are provided. Point and interval estimation of the process parameters and of some functions thereof are developed, as well prediction on some observable quantities that are useful in defining the maintenance strategy is proposed. Finally, the proposed procedure is applied to a real dataset consisting of the sliding wear data of four metal alloy specimens.

Energy savings are generally viewed as an effective way to cut GHG emissions, as there are huge potentials for improvements because of several barriers and constraining factors for implementing otherwise profitable solutions. Several different polity tools have been applied to overcome these barriers including local political programmes aiming at facilitating a change in the local companies. This paper draw on empirical data from one such local programme, the Carbon 20, carried out by 7 Danish municipalities.The paper present discussions in respect to the overall role and approach of the local authorities, evaluating the specific concept applied, highlighting the specific barriers and constraints encountered during the project so far, as well as how the local authorities can help the companies overcome these.With this paper, the author intent to provide some inspiration for other local authorities (and other intermediates in the energy saving area) for how they can interact with companies to assist them overcome different barriers and constrains taking a role and approach as a “reflective dialogue partner”.

Methane steam reforming(MSR) was studied in a membrane reactor(MR) with a Pd-based and a porous alumina membranes. MRs showed methane conversion higher than that foresaw by the thermodynamic equilibrium for a traditional reactor(TR). Silica membranes prepared at KRICT were characterized with permeation tests on single gases(N?, H?and CH?). These silica membranes can be also used for high temperature applications such as H?separation CO?hydrogenation for methanol production is another reaction where H?O selective removal can be performed with these silica membranes.