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Coverage of Slovakia's energy needs depends primarily on collecting energy from abroad (mostly from the Russian Federation). Therefore, the state is inclined to making substantial use of renewable energy sources, which are also environmentally less aggressive. Slovakia has a significant potential in geothermal energy. The systematic investigation of geothermal energy sources using geothermal wells started in 1971 in Slovakia. There are 120 registered geotherm al wells in Slovakia, which proved about 1787 l.s -1 of...

Experiences from various countries show that without initial state support it is not possible to build basis for applying of t echnologies using renewable energy sources. Presented contribution is orientated to the various mechanisms that are using for support of renewable energy sources. That means st ate regulation in this area generally and basic types of state donation policy in th e frame of European Union and their consequences on the market with renewable energy sources.

Urgent task of energy policy in the near term, in addition to diversification will encourage vigorous national economy, reducing dependence on natural gas and both demand-side measures (in the energy supply of buildings are mainly to improve the thermal protection) by measures on the production, transmi ssion and distribution (increasing efficiency of energy transforma tion and increasing the share of renewable energy at the expense of natural gas).Natural gas can be easily replaced in the supply heat buildings, a...

Some renewable energy sources, such as biomass, hydro, geothermal and tidal energy, produce reliable electricity, which can be distributed to remote locations. Other sources, like solar and wind depend on the weather, but it is predictable and so their usefulness may be suitably amended with permanent renewable energy sources. The vast majority of renewable energy in add ition to their advantages in terms of their source inexhaustibility also has significant drawbacks which significantly limit their expansion. For...

On global scale the nickel coa tings obtaining is realised with electrolytes that have the toxically composition that working at the temperature range 40 - 800C. In this paper was proposed an ecological solution to obtaining the nickel layers and composite coatings with nickel matrix and silicon. The energy consume is reduced be cause the working is passed on ambient temperature. The addition of silicon particles into nickel plating bath leads to significantly changes for the surface morphology and for the roughne...

Here we try to find a compromise way of controlling a continuous variable power system by adopting a hybrid architecture in which the renewable energy sources are coupled with the classic power grid. In such an architecture, a big issue is the control algorithm for management of the energy sources, which had to be designed in such a way that the final consumer remain powered on at all times. We proposed a control algorithm which compares the input and output powers, if the input power is lower than the output, the...

Widespread use of renewable energies is a global priority that must not be ignored. Optimal production and use of renewable energy sources is a necessity. In the current context, characterized by alarming incr ease in pollution caused by energy production from combustion of fossil fuels, is becoming increasingly important to reduce dependency on these fuels. Energy recovery and conservation aim at solutions for a substantial reduction in fuel consumption. In this context we can mention hydrostatic regenerative hyb...

Nor green business, however, designed precisely to reduce the amount of waste that modern society and its technologies generate, is not entirely trouble-free in relation to waste. This problem also applies to photovo ltaic. The issue of life cycle and the final disposal of modules and materials is more or less long a major role for industry. Total amount of photovoltaic waste in Europe is still relatively small and moves around 3800 tons in 2020, this number will grow to 35 000 tones. Sooner or later it will be ne...

Lead-free solutions for protective coatings as an alternative for ecological galvanized steel sheets obtaining were studied in this paper. The lead from zincing baths was eliminated and replaced with bismuth as non hazardous elements. Also other alloying elements (nickel, tin, and aluminium) in zinc melts were added. The making technology of these galvanizing free-lead alloys wa s established in accordance with alloying elements properties. The tec hnological conditions for obtai ning zinc-bismuth coatings with va...

Nowadays, when the amount of exhaustible energy resources in the world are reducing and their prices are increasing proportionately , mankind tries to find alternative sources of energy. Use of solar radiation has huge potential in th e future. Already today, the sunlight is transformed into heat or electric energy. For the conversion of solar energy into electricity we are using photovoltic cells. The Slovak Republic is in the use of photovoltaic systems on the tail in the Euro pean Union. Electricity produced by...

Structure of the mathematical model of underground coal gasification process in terms of material and energy (heat) balance is presented in this paper. Base inputs of gasification process are coal (coal model) and oxidant (a mixture of oxygen and air), which appropriate combination has to ensure the best possible conditions for the gasification process. The expected energy output from coal gasification process is a synthetic gas - syngas. Components such as ash, tar and unburned coal are side outputs of the proces...

The using of low-emission - renewable sour ce of energy (wind, solar and photovoltaic energy, geothermal energy and energy from biomass and biofuels) undoubtedly contributes to the retardation of climate changes. The energy is the essential part for the world function. Today is the achievement of reasonable energy consumption one of the fundamental roles. It has 80% of all greenhouse gas emissions in the world, which are the main cause of the climate change and stronger air pollution. Therefore it is needed to red...

The contribution deals by the suggestion of new manufacturing technology for hand- made screw blade for wind-power plant. A wind turbine is a device that converts kinetic energy from the wind into electricity for distribution. Wind turbine blades are most often fabricated by hand using multiple layers of fi breglass cloth. The traditional method is for the sheets to be cut to shap e, laid down in a mould by hand, sprayed or rolled with resins, and finally cured. The automation of the manufacturing of hand-made pro...

Well organized ventilation systems and air distributions of the school buildings in many countries still appear to be a t opical issue. A lot of various investigations indicated that IAQ problems appear not only because of low ventilation ra tes, but also in cases when the location of exhausted and mainly supply jets is not appropriate. The main motivation is the select of most efficiency air ve ntilation systems and di stribution schemes to improve IAQ for school buildings. The model of university classroom for p...

The work deals with reconstruction of family house on the part of energy for heating need. The essence has been to comparise individual alternatives, which are possible to realise in judge house. In the first part of work is the attention devoted to object describing and to heat loses values before and after the measurements. Than are particularly characterized alternatives of heating, their annual costs for heat production and for amount of fuel, invested costs and the portion of invested and overall costs. In th...

VSB – Technical University of Ostrava has a possibility to investigate changes in the rock massive during operation of heat pumps. Our new University Hall is heated up by the heat pumps. This object is the biggest building in the Czech Republic and in the Central Europe which uses this type of the system. Monitoring boreholes are situated in the area of heat pumps boreholes. They are equipped with heat sensors which monitor temperature changes in rock massive during the heat pumps operati on. This locality is ca...

The contribution shows the problems of unde rground coal gasification. Currently, this topic is timely, seeing that many coal deposits can not mine through traditional mining methods. Through underground gasification can be obtained from these deposits so- called synthetic gas - syngas, which can be conve rted into electricity or used in industry and households as fuel. Underground gasification technology has been verified in laboratory conditions for several experiments. Experiments differed fr om one by ways of ...

Iran is a country with an area of 1,648,198 Km 2 in the Middle East. When it comes to sun, there are 300 days of pure high UV sunshine in 95% of the country. There is a triangular great desert from center to the East of Iran, which due to its position receives a large amount of solar energy. Because this area is enclosed by the high ridge Alburz Mountains in the North, the Zagros Mountains in the West and the Makran Mountains in the East, there is no climate variability and also its geographi cal and environmental...

Slovakia falls behind the aims that were appointed in the field of the scrap economy. In our paper, we are concentrated on the valuatio n of the interest of Slovak citizens in the separated collection of the communal scrap in Slovak Republic, that is very low when talking about the mass. On the basis of th e questionnaire research we evaluate the interest in the separated co llection of communal scrap of citizens of the cities and villages acoording to the fact they live in habitable blocks, or in family houses . ...