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  • Energy use – in terms of efficiency
    61-66
    Views:
    147

    In the recent decades it has become apparent that the human race can lead to a polluting and energy- wasting lifestyle and the depletion of natural resources and an ecological disaster as well.

    Energy efficiency is the realization of the chance to see a wider use of renewable energy. Renewable energy sources can be found in large quantities in Europe. A proper exploitation of these would be important because of the "traditional" energy sources’s sate is very critical in many ways.

    The utilization of renewable energy sources depends on many factors. The local natural conditions significantly determine each country's different renewable energy potentials. I find to be important the natural conditions, such as, solar radiation intensity , the number of sunny days per year, the wind conditions , the volume and their energy characteristics of the geothermal power resources , land features , soil and rock quality, the supply of fossil fuels or the nuclear possibilities of energy production. The economic environment is also a major influencing factor for the utilization of renewables. The conditions of price of fossil fuels (natural gas, oil and coal), the price of nuclear fuel production and other energy costs significantly influence the demand for renewables, as well as the level of subsidy and government tax policy. In addition, the international and national programs, objectives, strategies, subsidies and regulatory measures as well as technological factors can have a significant impact.

    In my paper I point out the opportunities of renewable energy should be given to live. Nowadays the positive effects of their use is undisputed. In addition to the environmentally friendly produced energy, we should strive for energy conservation and energy efficiency as well. These expectations appear in practice, which can be directly perceived by citizens, in fact we should live accordingly. Furthermore, the environmentally relevant regulations of living conditions should appear as environmental demands.

  • Biofuel regulations in the USA and the EU
    25-31
    Views:
    113

    Climate change, the increasing dependency on crude oil and other fossile fuels, the expanding import and the increasing energy costs make the world’s societies and its economies vulnerable.

     The development of effective renewable energy resources has been a priority for the US since the first oil embargo. While there was only little progress for around two decades, biofuel use and production has been showing a rapidly increasing tendency since the mid 90’s.

     The EU’s objective of renewable energy resources is one of the main priorities of the Europe 2020 strategy. The European Union aims to increase the share of energy produced from renewable resources in the whole energy supply and by 10% in the transport-related energy supply by 20% until 2020.

     The renewable energy sector is the only one which is able to reduce GHG emission and pollution while utilising local energy resources and stimulating cutting edge industrial sectors; therefore, it is indispensable to develop a proper framework and regulation for supporting renewable energies.

  • Harvesting system established for the utilisation of Miscanthus sinensis ‘tatai’ “energy cane” in biomass power plants
    143-150
    Views:
    139

    The increasing demand for energy worldwide and the resulting environmental impacts of fossil fuels forced many countries to turn to renewable energy resources as a clean and sustainable alternative. More than a third of Europe’s binding renewable energy source target of 20% by 2020 will come from solid biomass for electricity and heating according to the National Renewable Energy Action Plans submitted by member states of the European Union (EU) to the European Commission. To achieve this goal long-term yield studies in renewable energy plants are important to determine mean annual biomass and energy yield, and CO2 emission. Field experiments worldwide and also in Europe have demonstrated that Miscanthus, a fast-growing C4 rhizomatous grass can produce some of the highest biomass and energy yield per hectare of all potential energy plants. Miscanthus is a plant that originates from the southern slopes of the Himalayas. It was bred for the Hungarian climatic conditions in 2006 under the name of Miscanthus sinensis ‘Tatai’ (MsT). The species has high frost and drought tolerance and high energy value. This is why there is growing demand for the biomass (lignocellulose) produced by growing this plant. The biomass, produced from the high yield energy reed, can be transported to power plants in large quantities, in forms of bales. Its household consumption is not yet significant. This study presents the external features, characteristics, propagation and plantation process of MsT energy reed. The study also demonstrates the harvest technology of the species worked out between 2009–2012 in Tata, Hungary and the options of supplying to biomass

    power stations.

  • Changes in weed flora of basket willow (Salix viminalis L.) under different soil nutrient supply
    116-120
    Views:
    127

    The world is in a continuous progress, as a result of which energy consumption and with this the release of gases with adverse impact show rapid increase. As a result of the survey conducted by the International Energy Agency, if the major economic powers do not initiate a change in their energy policy, the increase of energy consumption may as well reach 40 % by 2030. This increased energy demand is getting more and more difficult to fulfill with the fossil energy resources, which is to lead to an increasing significance of renewable energy resources. In Hungary, these energy resources are the best to provide with biomass growth. Biomass growth for energetic purpose can mostly be provided by energy plants, out of which “energy willow” (Salix viminalis L.) is outstanding with its high yield and with its excellent burning technology characteristics of its timber. The willow’s cropping technology is being established in our country. One of our tasks is to work out an adequate weed control plan. The professional and safe use of herbicides can increase the success of production. In our paper, we discuss the weed flora data collected on  treatments applied in the different fertilizer and compost. We started our survey in 2010. We examined twelve different fertilizer and compost treated areas. The dominant weeds were: Amaranthus retroflexus, Chenopodium album, Echinochloa crus-galli among annuals; Cirsium arvense and Agropyron repens among the perennials. 

  • Sustainable energy management – the importence of the renewable energy sources, their difficulties and chances
    145-154
    Views:
    71

    The biggest question of the century standing before us is that if people will be able to direct the development to sustainable direction. One of the components of global problems threatening
    us is the pressure that the energy management puts on the environment, which can be significantly lowered by utilizing renewable energy sources. The aim of my study is to draft the
    model of a sustainable energy management, putting the renewable energy sources into it in a sensible way, regarding the possibilities of Hungary.

  • Energy efficiency in Hungary and abroad
    147-150
    Views:
    118

    Nowadays decentralized energy supply and the energy security are becoming more involved. We should increase the share of renewable in the energy mix, addition to improve the energy efficiency. Hungary is not an abundance of fossil resources it is particularly important in the materials and energy-saving technologies, waste recovery, increasing the share of environmental energy. Our country has outstanding opportunities many areas for example, solar energy, geothermal energy, so we need to devote more attention to renewables in the future.

  • Opportunities of renewable energy use in Hajdú-Bihar and Szabolcs-Szatmár-Bereg counties
    143-146
    Views:
    119

    Today it's an important role of the renewable energy resources, improving energy efficiency, thereby contributing to sustainable, ecofriendly use of local energy resources. Globally intensify the requirements and considerations related to environmental conservation. In this light, the main objective of the Hungarian energy concept is to maintain long-term security of supply, the economy and the environment occurring contradictions. So there is a need for systems that, in compliance with EU environmental directives, acceptable cost level will ensure the desired and expected security of supply. In the study, three companies and other technical parameters of these are examined. For each undertaking, different results were observed. For two undertakings, we are talking about realized investments, in one case a prognosis was examined. All three companies contributed to the requirement of renewable energy sources reaching 13% in Hungary by 2020.

  • Renewable energy resources in the EU (Policy scenario)
    143-146
    Views:
    103

    The use of renewable energies has a long past, even though its share of the total energy use is rather low in European terms. However, the tendencies are definitely favourable which is further strengthened by the dedication of the European Union to sustainable development and combat against climate change. The European Union is on the right track in achieving its goal which is to be able to cover 20% its energy need from renewable energy resources by 2020. The increased use of wind, solar, water, tidal, geothermal and biomass energy will reduce the energy import dependence of the European Union and it will stimulate innovation.

  • Bioenergy production: are the objects realistic??
    53-58
    Views:
    80

    Currently we do not have the possibility to define our energy reserves, since we do not know the magnitude of extant material resources. The known petroleum (crude) supply will be sufficient for about 100 years at the longest, and according to the latest estimates in 2008 we will reach and even exceed the maximum level of oil extraction, and after this it is going to decrease.
    Hungary has good givens to go upon the way of sustainable energy economy according to experts, however a coherent government policy that lasts for not just one period is essential, and a sound economic- and agricultural policy is needed as well. According to the FVM’s under-secretary in Hungary more than 1 million hectares can be disposable for energy crop production. This would mean that 20 percent of the fields would be taken away from food production and on these fields energy crops would be grown. But we also have to take into consideration that the increase in energy plant production could happen at the expense of food production. If we would like to ensure the food for Hungary’s population from national sources we have to make calculations in determining energy need. In my research I set out the objective to determine the level of that specific turnover and marginal cost which supports the profitability of grain cultivation. With these indicators it is possible to analyze the economy and competitiveness of growing energy crops in the region of the North Plain. The alternatives of using cereals and rational land use should be also considered. A developing bio-fuel program can be a solution for the deduction of excess grain that is typical in Hungary for several years in the cereals sector. The pressure on the national market caused by excess grain can be ceased or moderated, and therefore the storage problems would decrease as well.

  • Caliometric characterisation of crop production byproducts
    55-58
    Views:
    139

    By the decreasing tendency of the fossil energy resources more emphasis put on the usage of renewable energy resources. The consideration of environmental protection and the efforts of the European Union make current the widespread usage of renewable energy within biomass energy. One of the determinative trends of biomass energy is the direct combustion of biomass. Characteristically woody stocks are produced for this aim, but there is a considerable potential in several byproducts of growing herbaceous plants or of other processes.

    In our study three byproducts of plant production have been investigated which appeared at the harvest. The Higher Heating Values of wheat, maize and sunflower byproducts have been determined by an IKA C2000 Basic adiabatic calorimeter. According to the statistical analysis of the measured data the HHV of the byproducts are different, and these values are in a negative correlation with the amount of ash in % (R2=0.873) appeared by the combustion.

  • Evaluation of sweet sorghum and sudangrass varieties by the viewpoint of bioethanol production
    57-61
    Views:
    122

    Bioenergy and biofuels are very important in today’s energy policy. These kinds of energy resources have several advantages against fossil fuels. Environmental protection is a cardinal point of widespreading these technologies but the economic considerations are important as well. In order to improve the rate of the renewable energy in the energy consumption, the European Union settled down a program which determines a minimum ratio of renewable energy in the energy consumption for each member country of the EU. To fulfil the requirements bioenergy and biofuels should be produced. This production procedure needs adequate stocks which are commonly agricultural products.
    One of the promising stocks is sorghum. This plant fits for bioethanol production due to its juice content being rich in sugar. In this study six sweet sorghum hybrids, two sudangrass hybrids and a sudangrass variety have been evaluated to determine their theorical ethanol production capacity.
    On the score of the results of the year 2009 it can be set that sudangrasses have a lower theorical ethanol capacity than sweet sorghums have. In the case of sweet sorghums 1860.29–2615.47 l ha-1 ethanol yields had been calculated, while the sudangrasses had only 622.96–801.03 l ha-1. After that throughout three years (2011–2013) the sweet sorghum hybrids have been evaluated in order to determine the fluctuations of the ethanol production capacity caused by the impact of the years. As a result 2425.44–4043.6 l ha-1 theorical ethanol capacities have been calculated, which means that sweet sorghums can be an adequate stock to produce bioethanol.

  • The use of renewable resources is an opportunity and an obligation
    13-17
    Views:
    100

    The renewable energy sources could be used in energy production, while no or only very slightly emit harmful substances to the environment. The solar, wind, hydropower, biomass and heat rational utilization of land contributes to greenhouse gas emissions.
    Renewable energy sources also reduces the dependence on fossil fuels, thus contributing to increase security of supply. The creation of local jobs to strengthen the area's population retaining ability.

  • Assessment of Environmental Susceptibility/Vulnerability of Soils
    62-74
    Views:
    83

    Soils represent a considerable part of the natural resources of Hungary. Consequently, rational land use and proper soil management – to guarantee normal soil functions – are important elements of sustainable (agricultural) development, having special importance both in the national economy and in environment protection.
    The main soil functions in the biosphere are as follows: conditionally renewable natural resource; reactor, transformer and integrator of the combined influences of other natural resources (solar radiation, atmosphere, surface and subsurface waters, biological resources), place of „sphere-interactions”; medium for biomass production, primary food-source of the biosphere; storage of heat, water and plant nutrients; natural filter and detoxication system, which may prevent the deeper geological formations and the subsurface waters from various pollutants; high capacity buffer medium, which may prevent or moderate the unfavourable consequences of various environmental stresses; significant gene-reservoir, an important element of biodiversity.
    Society utilizes these functions in different ways (rate, method, efficiency) throughout history, depending on the given natural conditions and socio-economic circumstances. In many cases the character of the particular functions was not properly taken into consideration during the utilization of soil resources, and the misguided management resulted in their over-exploitation, decreasing efficiency of one or more soil functions, and – over a certain limit – serious environmental deterioration.
    Soil resources are threatened by the following environmental stresses:
    – soil degradation processes;
    – extreme moisture regime;
    – nutrient stresses (deficiency or toxicity);
    – environmental pollution.
    Environmental stresses caused by natural factors or human activities represent an increasing ecological threat to the biosphere, as well as a socio-economic risk for sustainable development, including rational land use and soil management.
    The stresses are caused by the integrated impacts of various soil properties, which are the results of soil processes (mass and energy regimes, abiotic and biotic transport and transformation and their interactions) under the combined influences of soil forming factors. Consequently, the control of soil processes is a great challenge and the main task of soil science and soil management in sustainable development.
    The efficient control of these processes necessitates the following consecutive steps:
    • registration of facts and consequences (information on land and soil characteristics, land use, cropping pattern, applied agrotechnics, yields, with their spatial and temporal variability);
    • evaluation of potential reasons (definition and quantification of soil processes, analysis of influencing factors and their mechanisms);
    • assessment of the theoretical, real, rational and economic possibilities for the control of soil processes (including their risk-assessment and impact analysis);
    • elaboration of efficient technologies for the „best” control alternatives (best management practice).
    Scientifically based planning and implementation of sustainable land use and rational soil management to ensure desirable soil functions, without any undesirable environmental side-effects, require adequate soil information. In the last years such data were organized into a computer-based GIS soil database in Hungary, giving opportunities for the quantification, analysis, modelling and forecasting of the studied environmental stresses and for the efficient and scientifically based prevention, elimination or reduction of environmental stresses and their unfavourable ecological and economical consequences.
    Special attention was paid to the assessment of various soil degradation processes, as: (1) soil erosion by water or wind; (2) soil acidification; (3) salinization and/or alkalization; (4) physical degradation (structure destruction, compaction); (5) extreme moisture regime: drought sensitivity and waterlogging hazard; (6) biological degradation; (7) unfavourable changes in the plant nutrient regime; (8) decrease of natural buffering capacity, (9) soil (and water) pollution.
    The actions against undesirable environmental stresses and their unfavourable consequences are important elements of sustainable, efficient, economically viable, socially acceptable and environmentally sound crop production and agricultural development. These are joint tasks of the state, decision makers on various levels, the land owners, the land users and – to a certain extent – of each member of the society.

  • Harmonic development and biodiesel
    91-95
    Views:
    76

    An increased expansion of renewable resources and biodiesel is observed and prognosed, since fossile energy resources are about to run out. Hungary achieved outstanding sunflower years in the recent years in worldwide comparison. In the future, the feedstock of biodiesel production can also be rape besides sunflower.
    According to the concept of harmonious development, the balance between nature, society, economy and human environments is represented by their mutual presumptive character. Research and development need to be aligned into this system. Our aim was to examine the advantages and
    disadvantages of biodiesel production in different environments, using a model to do so. In order to maintain the harmony, the existing resources have to be managed properly, taking the correlations of the system into consideration. Targeted technological developments are necessary, similarly to the improvement of energy safety and efficiency.

  • Energy crops on less favoured (alkaline) soil
    115-118
    Views:
    99

    The reduction in fossil energy and row material sources induces growing demand for renewable resources. The growing demand for herbal raw materials has land use impacts as well. One way to reduce the conflict between the food and energy crops can be the utilization of less favored areas by growing energy crops. Among the potentially available areas for this purpose the salt affected soils (SAS) occupy a significant territories. SAS with structural B-horizon (meadow solonetz soils) represent the most wide spread group of SAS in Hungary. About half of these soils have been reclaimed and used as arable land and the remaining 50% are used as grassland. Sweet sorghum production for manufacturing of alcohol production was investigated in a long term amelioration and fertilization experiment on a salt affected soil (meadow solonetz). By means of regression analyzes the effect of sodium content of the soil and increasing mineral fertilizer doses were studied. According to the multiple regression analysis only the effect of nitrogen fertilizer was significant. On the solonetz type salt affected soil the effect of water soluble salt content of the soil was not significant, but there was a closer correlation between the ammonium-lactate sodium content and the yield of sweet sorghum. The maximum green mass was 45–50 t ha-1, in the case of low Na content and high level of nitrogen fertilization.

    In order to quantify the potential yield of natural grass vegetation the relationship between the soil forming processes and the grass vegetation
    was investigated. Beyond the different forms of Na-accumulation, the spatial pattern (mosaic-like characteristic) is also an inseparable feature of salt affected soils. The difference in the water regime, caused by the micro-relief is the main cause of variability. The run-on water keeps the deeper parts of the catena position wet longer. The wet situation causes more intensive leaching. In the low-laying parts of salt affected soils species preferring wet situations (mainly Alopecurus pratensis) are in majority. On the higher parts of the micro-relief species tolerating dry situations (mainly Festuca  pseudovina) are dominant. The yearly grass production of low laying areas can be 4–7 t ha-1 but because of prolonged wet  conditions the grass is not grazed and mowing can only be in old state. This old grass is not proper for feeding, but it may be suitable as energy plant. 

  • Competitiveness of the biomethane opposite with the CHP technology of biogas by definite plant size
    5-9
    Views:
    118

    The biogas sector has never before aroused so much attention as it does today. Combined heat and power (CHP) reliable and cost-effective technologies that are already making an important contribution to meeting global heat and electricity demand. Due to enhanced energy supply efficiency and utilisation of waste heat renewable energy resources, CHP, particularly together with district heating and cooling (DHC), is an important part of national and regional Green House Gas (GHG) emission reduction strategies.

    During my work I am going to use the basic data of a certain biogas plant than I assemble one model from that. Against the CHP technology I am going to plan a biogas cleaning-equipment. During my research it revealed, that in the case of a 1 MW output power plant it is not worthy to deal with biogas cleaning between national conditions. Investigating the quantity of heat recovery in the CHP technology it is obvious, that the net income at 1 m3 biogas is at least 72 times more than the cleaning technology (heat recovery is 0%).

  • The Dg RES generation, storage, utilization and integration program ’1 village – 1 MW’ of the Bükk-Miskolc Region, Phase 1–3.
    233-235
    Views:
    83

    The usage of renewable energy sources (RES) and the increase of energy efficiency could be the solution for the difficulties of the rural impoverished inhabitants. A rural development company with the support of the communities designs the development resources from the EU and the Hungarian State for RES generation and organizes the ’1 village – 1 MW’ RES generation, storage, distribution and usage integration.

  • Renewables in higher education
    151-154
    Views:
    134

    Unfortunately Hungary is not too rich in natural resources, so particularly important the materials and energy-saving technologies, waste recovery, increasing the share of renewable energy. It is a complex ecological strategy which priorities of the Hungarian education and calls on the student’s attention to ecological issues, pollution and the environmental load and look for specific opportunities for the realization of sustainable development. I consider, in addition to the specific operating continuously reduce costs of the campuses we should integrate the practical experience in to engineering education.