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Solar energy systems have emerged over the last decades as the cleanest and most abundant renewable energy resources available worldwide. Solar trackers are devices specially developed to enhance the energy efficiency of solar energy systems. This paper presents the design and implementation stages of a reconfigurable hardware technology-based two-axis solar tracker platform, specially conceived to improve the energy efficiency of photovoltaic (PV) panels. The main module of this platform is the NI MyRIO ready-to-use development system built upon a high-performance Field Programmable Gate Array (FPGA) processor that controls the entire solar tracker unit. Optimal tracking of the sun movement and obtaining the maximal energy efficiency rate is achieved by simultaneous real-time controlling both the captured sunlight intensity and PV cell temperature magnitudes. In this way, a robust and versatile positioning system has been developed that performs a high precision and accurate tracking pathway. All the control algorithms are implemented there under the LabView graphical programming software toolkit. The final solution boosts in a useful and modularized tracking system that looks useful in a wide range of applications both in industrial and domestic project sites with different power scales.

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-ideal hardware: energy efficiency, estimation, and capacity limits . IEEE Transactions on Information Theory , 60 ( 11 ), 7112 – 7139 . [10] Ali M

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Abstract

In this paper we analyse the trends and developments of energy imports as a percentage of gross inland energy consumption including bunkers in Hungary and the European Union countries between 2000 and 2011. Data show that the average of the energy dependence increased in the EU27 Member States (7.1 percentage points) and in Hungary, too (3.4 percentage points). The energy intensity in Member States is examined as well. According to the data the energy intensity decreased in the majority of the Member States, the average decreased by 16 percent.

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Abstract  

Numerous and diverse mathematical methods have been used to model the full-energy photopeak (FEP) efficiency-to-energy relationship. All of the methods attempt to approximate this relationship using numerical analysis methods. Sophistication of the mathematics does not guarantee a meaningful and accurate determination of the physical relationships being modeled. This discrepancy stems from the fact that the data being modeled may suffer from spectral and nuclear effects which alter the counts in the full energy photopeak resulting from absorption and attenuation in the active volume of the diode, in the intervening materials between the detector diode and source, within the source itself, and in the shielding around the detector and source. Data must be free of these effects either as a result of acquiring the spectral data in geometries which minimize or eliminate these effects, or by pre-treatment of the net area counts to correct for these effects. If these corrections are not possible, then the choice of mathematical fitting method should be constrained to provide results which are consistent with physical-theoretical considerations of the energy-efficiency relationship being modeled. If possible, the method chosen should also provide a meaningful estimate of the uncertainty associated with the approximation of this function.

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://www.eastlothian.gov.uk/downloads/download/869/fuel_poverty_explanatory_note . [8]. Tackling Fuel Poverty in Europe — Recommendations Guide for Policy Makers, European Fuel Poverty and Energy Efficiency — EPEE , 2009

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A Data Centre (DC) as critical, energy-hungry infrastructure is dominated by two main driving forces: i) Availability and ii) Energy requirements. As a result of increasing energy costs, algorithms for optimising energy efficiency have been devised. However, these algorithms do not take availability into consideration.

This paper aims to present a combination of Failure Mode, Effects and Criticality Analysis (FMECA)/Reliability, Availability, Maintainability (RAM)/Energy Analysis as an innovative approach for harmonising availability and energy efficiency in DC. Based on various measures defined by FMECA/RAM, corresponding availability and reliability are modelled and calculated. In parallel, potential energy saving measures are included in RAM simulation to quantify their influence on the availability and reliability of DC infrastructure. As a result, a set of the most promising optimisation measures is selected.

Results show that some energy saving measures are highly correlated with availability. However, required data centre availability can be achieved with improved energy efficiency if the right set of optimisation measures is implemented. This approach guides DC managers to identify improvement potentials in terms of availability and energy efficiency, providing a reliable decision basis for future investments.

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energy efficient in many aspects of their design [ 1 ]. Furthermore, they are seen as buildings with the largest energy consumption. The envelope has a significant impact on energy efficiency and the quality of the indoor environment. It covers

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other compound. However, there is no report about using the relationship between lipid content and energy to estimate growth energy efficiency of lipid production. Previous data demonstrated that there was a good linear relationship between γ x σ x and

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The object of the examination is a typical office building of the 1990s, owned by a multinational company -Siemens- dedicated to energy awareness. The building also meets the energy efficiency category ‘A’ under the 7/2006 TNM Hungarian regulations concerning the energy performance definition of buildings. However, demand has emerged to implement additional changes to reduce energy usage whilst keeping the current climate comfort or even improving it. International experience forecasts around 30% energy saving potential due to optimization of the building automation and energy management system, and thus the interaction and collaboration between the building geometry, structures and services systems. The project has been built in the IDA ICE complex building energy simulation program. Running a one-year dynamic simulation will provide data that can be compared with the measured data of the actual building, so the model can be adjusted and validated to real data. After the calibration it is now possible to test the ideas under safe conditions, in a virtual surrounding. Once a particular vision of the model is proven to work effectively, it is possible to apply this to the real building control management as well.

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consider during the design process [ 1 , 2 ]. For this reason, study [ 3 ] attempts to promote skyscraper energy efficiency by investigating climate responsive design strategies, for example orientation, thermal properties of the building envelope, and the

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