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  • The effect of plant density on maize yield in average and extremely dry years
    7-16
    Views:
    114

    The yield safety of maize has not been satisfactory in Hungary for decades. Yield is influenced by the combination of several factors.
    In recent years, the frequency of dry years increased and fertilization decreased. These factors call for a rational determination of the plant density.
    I studied the relationship between plant density and yield in 2003-2004 and 2007 on meadow soil. 
    In 2003, the weather was dry. In the vegetation period, the amount of precipitation was 78.5 mm lower and the temperature was 0.97 °C higher than the average of 30 years, the number of hot days was 47-60 (days with a temperature higher than 30 °C). However, we obtained favourable results under experimental conditions in 2003 after wheat as a forecrop using the fertilizer Kemira Power. 
    The weather in 2004 was favourable. In the vegetation period, the amount of precipitation was 93.2 mm higher than the average of 30 years.  Although, the distribution of the precipitation could have been more favourable. The yield of the hybrids ranged between 8.87-10.42 t/ha. Among the studied seven hybrids, the early hybrids gave the highest yield at the highest plant density of 90 thousand plants/ha (PR38Y09, PR38A67, PR37D25, PR37M34). However, FAO 400-500 hybrids gave favourable results also at the low plant density of 45 thousand plants/ha (8-9 t/ha). At this plant density, the aeration of the plant stock was better and the hybrids were prone to bringing several cobs. Yield stagnated with increasing plant density (60 thousand plants/ha), then at 75-90 thousand plants per ha, the yield started to increase again.
    In 2004 the yield of hybrids was considerably higher than in the previous year. In contrast to yields of 8.87-10.42 t/ha in 2003, yields in 2004 were around 9-12 t/ha.
    The yield of the hybrid XO 902 P is above 12 t/ha already at a plant density of 45 thousand plants/ha. It gives maximum yield at the plant density of 90 thousand plants/ha.
    The hybrid PR38P92 showed a good response to changing plant density, but its yield was only 9 t/ha at the low plant density value.
    In a favourable year, the yield of the hybrids PR38B85, PR37W05, PR37D25, PR37K85 at a plant density of 45 thousand plants/ha 11 t/ha, while at the higher plant density of 90 thousand plants/ha, it ranges around 13-15 t/ha.

    Hybrids PR36K20, PR35Y54, PR34H31 have a good individual yield and they are prone to bringing several cobs in favourable years at a low plant density. Their maximum yield at the plant density of 90 thousand plants/ha is almost 16 t/ha.
    In 2007, the weather was similar to that of the extremely dry year of 2003. The amount of precipitation in the vegetation period was 41.9 mm lower than the average of 30 years and its distribution was not favourable either.
    In the optimum NPK fertilizer treatment at an optimum plant density, the yield of hybrids ranged between 9.32-10.73 t/ha. The highest yields of 10.22-10.73 t/ha were measured for hybrids PR38A79 (FAO 300) and PR35F73 at a relatively low plant density of 60 thousand plants/ha.
    In the average of the hybrids, the optimum NPK dosage was N 131, P2O5 82, K2O 93 kg/ha active ingredient.

  • Harvesting system established for the utilisation of Miscanthus sinensis ‘tatai’ “energy cane” in biomass power plants
    143-150
    Views:
    158

    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.

  • The analysis of the fair data of a solar energy power plant with SPSS
    60-63
    Views:
    130

    The use of fossil energy sources greatly damages the environment. Moreover, the quantity of these energy sources is limited. Therefore, it is important to increase the share of renewable energy sources (solar, wind, water and biomass) in energy generation.
    Huge amounts of energy (1100-1300 kWh/m2 per year) arrive at the earth from the sun, and are utilized in passive and active ways. One of the active applications is photovoltaic current production, in the course of which electricity is produced directly with PV – panels. This can be fed into a grid. At the University of Debrecen is a solar energy power plant from September 2005 in operation. The electricity performance of the incorporated PV-panels (Kyocera, Dunasolar, and Siemens) are 8.64 kW. The are of PV – panels is 110 square meter. With the aid of the data storage, the tension, current, temperature of the PV-panels, global radiation, air temperature, wind speed, wind direction and the achievement is measured by the ac network.
    The effect of the shading on the performance of the PV – panels and the solar energy power plant is examined. The analysis and the graphic representation of the experiment results are carried out with SPSS per grief. We produced per grief.

  • The examination of the profit-making capacity of the wooden chip-based large-scale product path
    21-26
    Views:
    139

    Heating with wooden chips would provide a significantly cheaper energy production alternative for the local governments in heating their facilities and in district heating as well. The raw material should be available in the appropriate quality, quantity and at the right time. This type of heating requires the well-organized and joint work of the forestry, transporting, processing and receiving plants. This activity might be realized in the form of non-profit clusters. In order not to suffer any losses, the participants of the product path should carry out a very careful planning regarding the factors appearing in heating with wood but missing from gas heating. One such critical element is the transportation distance which might make the basically cost-efficient wooden chip-based heating process significantly more expensive.

    One of the main findings of my paper is that the transportation distance should be at most 23 kilometers for the wooden chips to be worth (economical) using against gas. From the viewpoint of practical use, this can be interpreted as the distance between the forestry and heatproducing units. By determining the constant and varying costs of transporting and chopping and from calculating the initial contribution, I concluded that the profit-making capacity of the product path would be sufficient for an energy-related investment. According to my calculations, by remaining within the economical transporting distance of 23 kilometers, such long-term savings might be achieved compared to gas heating which would partly cover the establishment of a biomass-based power plant or heating plant.

  • Competitiveness of the biomethane opposite with the CHP technology of biogas by definite plant size
    5-9
    Views:
    131

    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%).

  • Vegetable production based on waste heat in closed greenhouses considering economic usage and competitiveness of the European Union
    41-44
    Views:
    129

    The study investigates two professional fields; the questions of vegetable production in greenhouses, the necessary steam supply and heat regulations. The actuality of this investigation is provided by the planning of a combined cycle power plant of 2400 MW in Hungary. According to the plans the steam developing by generating electricity in the power plant can be used to intensify the vegetable production. In my current study I present the experiences and results gathered as member of the research and development team led by Mr. Dr. Sinórós-Szabó.

  • Az elmúlt tíz év változásainak vezetői értékelése különböző szervezeti formában működő vállalatoknál
    82-86
    Views:
    122

    revolutions and changes. Effects of these changes can be sensible at all parts of agricultural production. It results in new ownership and organisation structure. Agriculture has to suit to the new circumstances of changed firm-size and structure. These kinds of changes essentially define conditions of agricultural production in the future, and they have an affect on husbandry of enterprises.
    To be succeed in managing changes, we have to know the reasons of these alterations and nature of them. It is very important to get to know the advantages and disadvantages of the typical change-management methods and its typology. These methods are more elaborated and widespread at industrial enterprises. It is necessary to get to know the nature, characteristics and reasons of changes, and we should work out ways agricultural companies, taking notice of their speciality.
    The methods and means of examinations
    We aimed to point out what kind of changing processions were typified the activity of agricultural ventures. What are the speciality, strains, the arousing and obstructive factors of nowadays changes. We made questionnaire and sent them to numerous enterprises.
    Most of the answers show that leaders are „floating with flow” and most part of their power is used to fight back actually challenges. Generally consciousness is missing, so they are not govern the events still more they are passive objects of occurrence.
    Naturally, the given answers show, that the most important changes of past are changing of markets, importance of quality production and changes in the structure of enterprises. And – especially at companies, which deal with plant growing –, modifying of structure because of compensation.

  • Reduction possibilities of the production costs of green electricity by using waste heat
    15-20
    Views:
    195

    In my study, I examine the possibility of the reduction of green electric power’s gross production cost. My research topic may have wider considerations, since in the case of CHP technology the utilization of by-product thermal energy is not possible, and the whole production cost devolves upon green electric power. I introduce five options for the use of the heat energy, based on national and international literature and in-depth interviews.

    From the aspect of efficiency, it can be stated that as alternatives, beer production and desiccation may be mentioned, since these two models were appropriate for the utilization of the total quantity of waste heat, and in the given circumstances the lowest reduction of green electric power’s production costs was achieved in these cases utmost.

  • The Presentation of Debrecen University’s Solar Energy Power Plant
    259-263
    Views:
    97

    Energy plays an important role in everyday life and in the economy. The use of fossil energy sources greatly damages the environment. Besides this, the quantity of these energy sources is limited. Therefore, it is important to increase the share of renewable energy sources (solar, wind, water, biomass) in energy generation. Huge amounts of energy (1150-1300 kWh/m2) arrive at the earth from the sun, which utilized in passive and active ways. One of the active applications is photovoltaic current production, in the course of which electricity is produced directly with PV-Panels. This can be fed into the grid.

  • Seed biology and possibility of improvement of seed germination capacity on Virginia mallow (Sida hermaphrodita L. Rusby)
    71-76
    Views:
    157

    Sida hermephrodita or Virginia mallow is a perspective perennial herb in the Malvaceae family able to yield a biomass crop through the last two decades. Additionally, the plants have a lot of uses and benefits for instance it can use as a fodder crop, honey crop, ornamental plant in public gardens. It has favourable features like fast growing and resistance against the disease and climatic fluctuations, etc. Sida is in the beginning phase of domestication therefore it has a serious disadvantage: the low and slow germination as a big part of wild plants. Due to the expressly low germination percent the need of seed showing of driller is should tenfold, 200 thousand seeds/acre instead of 10–20 thousand what is not available and expensive Therefore practical purposes of our research of seed physiology was to increase the seed germination percent in a available, basically wild Sida population. In the first stage of our experiments we examined two factors relating to seed germination percent and seed germination power during our research: the influence of hot water treatment and the effect of exogenous or endogenous infection of seed. However, in our germination tests, utilizing scarified seeds with hot water (65 oC, 80 oC, 90 oC), from 29,3% to 46% germinated from those samples which were collected from the population of Sida hermaphrodita in Debrecen. The average germination for all season was 5–10% without treatment and rinsed using hot water up to almost 50%. When physically scarified used, the oldest seeds showed the best germination (46%) after the hot water operation in spite of the previous studies. We discovered that apparently there are close relationship between the seed fresh weight or water uptake capability and the percentage of infection. Following these recognition we modified our technique,in such a way that we fractionated the seeds based on their fresh weight/or relative density before we carried out the treatment. When we filtered the floating seeds on the surface of water, the hot water treatment was performed considerably better on the sunk seeds after separation. Therefore, by this special priming process we were able to reach 80% germination capacity of Virgina mallow seeds under laboratory conditions (26 oC without illumination).