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This research work describes cost-optimal calculations for existing buildings of different categories and main building elements, as well as comparison with the existing energy requirements. Calculations are based on Directive 2010/31/EU and on the Commission Delegated Regulation (EU) No 244/2012 with the associated Guidelines. Those documents are used both ? for the calculation of cost-optimal energy performance for a whole building (MWh or kWh/m2 per year) and for the assessment of optimal U-value for different ...

Results of research into the choice of rational parameters of thermal regime in coal mine workings of the permafrost zone which are minimizing energetic and economic expenses of creation of normative parameters of mine microclimate are presented. It is determined that there is an optimal temperature to which the air in the coal face should be heated. It is demonstrated that the most rational method of air heating is the one employing heating devices distributed along the length of the coal face. Basic criteria of ...

This paper aims to provide an overview of the technologies for the use and implementation of phase change materials, in order to identify possible applications in energy efficiency, reducing energy losses and reducing carbon dioxide emissions, while at the same time bringing a contribution to identifying applications in passive house designs for reducing thermal bridges and providing heating and cooling requirements in extreme weather climates, as well as aspects regarding the integration of phase change materials...

The performance of solar modules is fundamental during the conversion process in electrical energy, depending on the temperature of the solar cell. The photovoltaic power and efficiency decrease with temperature rise, Tc. In this paper are found useful aspects regarding the increase of the temperature of solar cells correlated with commercial photovoltaic panels, based on thermal monocrystalline silicon. Correlation of all parameters in terms of materials used by the photovoltaic industry, as well as weather condi...

There are plenty of facilities, machinery and equipment, either stationary or mobile, which require hydraulic operating power, generated by low-flow pumping systems at high pressures. Such systems can be met in stationary applications, in which energy efficiency is important, while the pulsating nature of flow does not disturb, and also in dynamic applications, in which both energy efficiency and flow rate regularity are important. The first category of applications includes: static pressure tests on deepwater dri...

Cogeneration, or combined heat and power production (CHP), delivers both electricity and heat simultaneously, which achieves high overall energy efficiency. Although CHP technologies are state of the art, and advantages of their adoption are well known, 70% (European Union) to 80% (worldwide) of the existing potential remains untapped. Initiatives fostering more widespread uptake of cogeneration so far often focus on large scale electricity supply schemes combined with the operation of district heating, while the ...

This article is referring to an analysis regarding the project management of a big size energy efficient commercial building in Romania. There is made a project management analysis status for the construction building project, according to its approved design for the execution. After that, there is shown the project management status analysis for the first operational year, right after the end of the building construction. There are presented the main aspects of the project management tasks for the developed comme...

Energy efficiency of buildings is one of the directions for implementing a sustainable community development program. The purpose of this paper is to present a calculation algorithm for the transfer of thermal energy between buildings. In stationery regime, this problem is reduced to solving Laplace's accomplishment with the given frontier conditions (Dirichlet's problem). For the general case, it is not known the analytical solution of these problems. Contemporary computing tools solve this problem using numerica...

Countries around the world are concerned with securing enough fuel and energy for their national economy. At present it is important supply of buildings with energy and their efficient consumption. The economical use of energy and fuel in the non-productive sphere consists of rationalizing energy consumption in the building and energy supply to the buildings. The most energy consumed is recording heating of buildings the reason is to cover thermal losses. The European Union is focusing on supporting the modernizat...

Multifunctional motor vehicles are equipped with one or more working mechanisms actuated by hydrostatic drive systems, which consume most of the power installed on such vehicles in which the primary mechanical energy is generated by an internal combustion engine, usually Diesel engine. Given the large number of daily running hours, (of multifunctional motor vehicles) the energy consumed by working mechanisms becomes important, the same goes for the expenses, and therefore it is required to be used with maximum eff...

The increasing demand for energy imposes strengthening the energy efficiency as a part of energy management on every level, with stress on production plants. Present paper is focused on energy management in renovated pellets production plant in Shumen town, Bulgaria. A comprehensive comparative analysis between the new wood pellets production line and substituted one is conducted. The net energy savings per year are calculated. The improvement of production line results in enhancing energy efficiency on every stag...

The implementation of the Energy Efficiency Operational Indicator (EEOI) by the International Maritime Organization (IMO) is a consequence of the need to specify quantified ships? energy efficiency of the vessels in service. The EEOI enables to monitor the efficiency of the ships in operation in a specific period of time based on an actual operation data. In reference to vessels other than ships which are designed for transporting passengers and / or goods (for which the EEOI has been developed), the application o...

Can civilisation at its current level of development afford the further wasting of all forms of energy? This is the question that forms the foundation of the entire philosophy of energy saving, and - to be more precise - of the work towards its efficient use. The greatest consumers of energy are mega-metropolises, as the amount of energy required to build them, produce all the necessary construction materials and their transport to the construction site, followed by the occupancy of the structures that have thus b...

The efficient use of cogeneration systems depends on both the heat demand variations and on the restrictions imposed by the related legislation. In this paper, in order to optimize the operating regimes of a Combined Heat and Power Plant, authors have determined the correlation between functioning modes of the plants? equipment and the possible solutions to satisfy with precision the consumers? heat demand. Often, optimizing only the operating regimes can be non-profitable, especially for the case of modern and pe...

One of the most important stages of the rehabilitation process, in the case of historical buildings, is to find the best solutions that can ensure, in the most efficient and nonaggressive way, the thermal comfort inside the building. In the study of this case, the authors identified several essential aspects in determining the best practices for assuring the heat consumption in buildings declared as historical monuments dating back to the 18th century. Among these we can mention: the destination of the building (t...