Advanced Materials Research Vol. 899

Abstract: The energy demand of buildings represents in the balance of heat use and heat consumption of energy complex in the Slovak national economy second largest savings potential. Their complex energy demands is the sum of total investment input to ensure thermal protection and annual operational demands of particular energy systems during their lifetime in building. The application of energy systems based on thermal solar systems reduces energy consumption and operating costs of building for support heating and domestic hot water as well as savings of non-renewable fossil fuels. Correctly designed solar energy system depends on many characteristics, i. e. appropriate solar collector area and tank volume, collector tilt and orientation as well as quality of used components. The evaluation of thermal solar system components by calculation software shows how can be the original thermal solar system improved by means of performance. The system performance can be improved of more than 31 % than in given system by changing four thermal solar system parameters such as heat loss coefficient and aperture area of used solar collector, storage tank volume and its height and diameter ratio.

Abstract: In order to reduce the energy demand leads to the creation of alternative ways, how to store energy for extended time period and cover starting part of winter term with heating. One possibly way is to store solar energy in the soil under and near the building. This article focuses on comparing the distribution and thermal unsteady field in the seasonal distribution elements of the ground storage located under the building. The comparison will occurred change of accumulated material properties and optimal distance distribution pipes or elements, so as to create the most efficient storing systems.

Abstract: In the architecture design is indispensable to extend the technology and materials, environmentally friendly, energy saving or energy capable (clean, no fumes) produce. The solution appears to be a combination of natural construction materials - primarily wood for timber constructions, wood products as a sustainable material and the use of alternative energy sources, in the building industry (addition to other) mainly photovoltaic (PV) installations. One of possibility for building industry appears to be use of natural construction materials - primarily the use of wood and wood products (as a sustainable material) for build a timber constructions and simultaneously the use of alternative energy sources (in building industry addition to other) mainly photovoltaic installations. The article refers to the possibilities of integration of PV systems in architecture in their various forms of application into the roofs and facades.

Abstract: Paper deals with theoretical electricity storage possibilities. Theoretic electricity storage system is integrated into system of small photovoltaic power plant (32 m²). Panels are located in the roof of the passive house. Paper shows time distribution of energy flows (PV produce, house energy consumption, storage systém energy coverage etc.) during the days and during the years. Paper shows photovoltaic panel geometry influence on fluctuating of electricity produce and whole this system during the year. Paper closes the discussion about suitability of such electricity storage system for Central Europe region.

Abstract: Biomass is a common fuel for small combustion equipment and also for heating plantsand power plants. Combustion of firewood, wood briquettes and pellets dominates in households.Thanks to high demand for biomass fuels its prices grow and it is necessary to look for cheaperalternatives. One of the alternative fuels can be foliage. In cities there is in autumn usually a plentyof fallen leaves. These leaves - foliage has to be composted or otherwise disposed of. Instead oftreating foliage as a waste it can be used as an alternative fuel. To serve as a viable fuel source thefoliage has to be processed into briquetts.This article deals with possibilities of producing briquettes from foliage and evaluation of theircombustion quality in small combustion equipment.

Abstract: Insolation of the total area of PV arrays is the precondition of their smooth, undisturbed regime. On flat roofs the PV arrays are arranged typically in rows. In many design guides whilst checking their insolation a typical fault is that the distance between the rows is adjusted to the solar altitude at noon in December. Nevertheless in this case the undisturbed insolation is guaranteed only theoretically for a moment: just at noon, practically for a few minutes. It is to be pondered by the designer, how long should be the period of the obstruction-free solar access: if it is four hours, the altitude at 10 or 14 oclock must be considered. Certainly the result will be a greater distance between the rows however in this case less energy collecting area can be put on the roof. There are two options: either to insist on the operation in December at the cost of less energy collecting area or to abandon the energy production in this period in order to have larger energy collecting surface. The question is the yearly balance: irradiation round the year onto a smaller surface or to make use of the less irradiation on a bigger energy collecting surface.

Abstract: This article describes a new type of hollow-fiber heat exchanger that provides similar heating performance to conventional metal heat exchangers commonly used in air conditioning systems but at lower cost and greater simplicity. While factors such as fragility and element fouling have yet to be optimized, the exchanger shows great promise for application in buildings aiming at close-to-zero energy consumption.

Abstract: Recently, there has been a tendency of increased complete reconstructions of historical buildings that have not been administered, nor used and have subsequently fallen into disrepair. The acting humidity can be effectively removed, using ventilated floors. The paradox is that these methods have been used for many centuries and until recently, only in laymans terms. The remaining problem involves drafts in air cavities in general. To assess the airflow in the air cavity, recently commonly used CFD simulations can be employed. In this article CFD simulation of underfloor air cavity created by special fittings is verified by means of laboratory experiment.

Abstract: Implementation of the ventilation ducts is one of the ways how to reduce the moisture in the vertical masonry structures. Functional ventilation ducts provide air inlet and outlet, which absorb diffusing moisture from the rehabilitated walls in these ducts. This causes the reduction of moisture in the structure. The implementation of the ventilation ducts is associated with the worsening of thermal parameters of the rehabilitated walls. This paper compares three variants of structural solutions of ventilation ducts and their impact on thermal parameters of the rehabilitated structure.

Abstract: The air quality in the classrooms of primary schools is an issue that is high on the agenda. They are devoted to the study and Europe. They show a wide variation in air requirements by occupancy class. During weekends and holidays, it is not necessary to meet the health requirements for air taking into account the presence of students. It is possible to specify boundary conditions, which influenced thermal requirements for building envelopes, by finding and setting various intensities of air exchange, depending on the occupation and function of the building. This fact should result to improving of the energy efficiency of primary school buildings and reducing of operating energy costs.