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  • 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. 

  • The energy balance of maize production – alternative approaches
    59-63
    Views:
    145
    Agricultural production is a crucial area, perhaps the most important for humanity. This is the only area which cannot be avoided. Therefore, it is of utmost importance to know how sustainable the system is in the long run as regards energy consumption. We have chosen the maize production sector as the main focus of this study. This crop is especially important all over the world, therefore; it requires significant input also in terms of energy. Currently, the system of maize production (as with the others) operates as an open energy system.
    This study aims to examine how much of the agricultural land’s energy demand could be met with the help of the byproducts of 1 hectare of agricultural land - operating as a closed system, using only the remaining maize stalk and cob byproducts for energy - under the conditions of Hungarian maize production.
    Energy demand is largely determined by the land’s fertilizer requirement, followed by the input factor of the energy demand of the machinery during earthwork and transport.
    The study assumes that the energy from the byproducts of maize production will be used exclusively with biogas technology. This can even be implemented on a county level. The final question is whether the maize production system will be able to sustain itself solely by using its own byproducts.
  • European best practises for district heating
    47-49
    Views:
    167

    In my current article I deal with the broadening extension of district heating that is highly beneficial from environmental and climate protection aspects. I present the energy efficient and environment friendly district heating upon some outstanding European best practises.
    District heating is of utmost importance concerning sustainable and secure energy supply because the share of the renewable energy sources continuously and gradually increases against the fossil energy sources (natural gas, crude oil) within the total energy consumption due to the directives for heat production of the European Union. As a consequence of that import energy dependency and coal-dioxide emission decrease in several countries like Hungary as well.

  • Operation experiences of the PV system of an office building utilising environmental energy
    179-182
    Views:
    101

    One of the most important research directions in the building sector is reducing the energy consumption. In Hungary the residential sector is the biggest energy consumer with 40% from the total energy consumption of the country. One possibility to decrease the energy consumption is using renewable energy sources. In this work I show a short description of PV cells and some measurements.

  • 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.

  • Operational experiences of a geothermal heat pump system
    115-118
    Views:
    119

    Energy consumption nearly 40% operation translates of the buildings in Hungary. In the last 5–8 years we can see a breakthrough in the field of low energy buildings, increasing the demand for buildings 'energy efficient', and realized several successful investments in our country. Nowadays thanks to the application system the number of public buildings increased environmental energy recovery system has been growing such as solar power, heat pumps.

  • Examination of physical properties of final product and drying properties of combined (convective pre-drying and freeze finish-drying) dehydration method
    5-12
    Views:
    135

    In this study, the effects of freeze drying (FD), hot-air drying (HAD) and combined drying (HAD-FD) on drying characteristics, energy uptake, texture, rehydration and color of carrot were investigated. Results showed that HAD-FD significantly improved the drying time compared with FD under the same operating conditions, and the HAD-FD can reduce the total cost of dehydration. The drying kinetics was described by the Henderson-Pabis and the third degree polynomial models in the case of HAD, FD and HAD-FD. The HAD carrot samples were exhibited shrinkage, case hardening, poor rehydration and brown surface. The FD carrot cubes appeared porous structure, excellent rehydration, soft texture and loose color. The HAD-FD samples were superior to HAD products and was nearer in quality to FD products with respect to appearance, rehydration and surface resistance (texture). Finally, it is concluded that HAD-FD is effective in improving the FD drying rate. However, the combined drying has a small-scale adverse effect on product quality.

  • Health factor in food consumption
    125-132
    Views:
    72

    Consumer lifestyle and health are relevant factors to understanding consumption preferences. In the last few decades the number of lifestyle diseases has dramatically increased. The main cause for these diseases is the change in lifestyle; including a lack of attention to physical activity and good nutrition. Health and lifestyle are important factors by purchase decision process. In accordance with these, I examine the consumer behaviour toward soft drinks with special regards to healthy lifestyle and the state of health. My examinations can be considered mainly as a
    qualitative research, which can serve as a basis for further analyses and research, however, the conclusions and experience gained from it are worthy of consideration. I differentiated five soft drink categories: ice tea, carbonated soft drinks, fruit juices, mineral waters, sport and energy drinks and studied the consumer behaviour toward them. The study focuses on the consumption of these and the factors influencing their purchase with special regards to lifestyle.

  • Biofuel production and its quality standards
    137-141
    Views:
    110

    The increasing consumption due to the decreasing amount of fossile energy resources, as well as the increasing fuel prices and living standard will justify the better utilisation of the opportunities lying in biofuel production. Certain countries produce biofuels for their own use or they even export them. However, there are countries which have not decided which feedstock and technology to use. Biofuel – mainly biodiesel and bioethanol – use greatly contributes to environmental protection, decreased CO2 emission and reduced greenhouse effect.

  • The applied mechanical equipments for wastewater treatment in the észak-Alföld region
    171-178
    Views:
    146

    In this study we presented the results of a survey research, which was performed during 2015 at 34 sewage treatment works, operating in Észak-alföld region (Hungary). The survey focused on applied mechanical equipment and works of art of the sewage treatment establishments.

    The results of the survey showed that the majority of the examined sites (approx 65%) are working with capacity utilization of 50–100%,merely the 12% of plants was overload. It was found analyzing of specific energy consumption of the sites that the largest value (1.1 kWh per m3) was at the plants with smaller capacity (0–1000 m3 per day). It was clear during the questionnaire processing of the survey that almost all of the works applied activated sludge for sewage treatment The sludge treatment of the sewage plants is conducted by two methods; aerobic- and mixed (anaerobic and aerobic) sludge stabilization. We suggest for the plants with small capacity to use deep aerators, since anachronistic method used the at 3% of the settlements.