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1871 Uppsatser om Energy losses - Sida 3 av 125
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When harvesteing ley there is always mechanical losses from the harvest machines. During
the last years the roundbalers with knives,cutting the material-are more common, This use
increase the mechanical losses of material.
MATERIALS AND METHODS
The roundbaler which used in this test was a Krone Vario Pack 1500 Multi Cut. This
roundbaler has 17 knives. The theoretical length of cut was 64 mm. During the test we
stretched a rubber tarp under the balechamber and collected the materials which fell down
from the balechamber.
Utvärdering av energieffektiviseringsåtgärder på Bokelundskolan i Växjö
The purpose with this report is to examine how the implemented energy efficiency measures on Bokelundskolan in Växjö have had impact on the energy use. The measures which have been implemented are, new ventilation system, new heating system, optimized adjustment of the heating system, new windows with U-value 1.2 and lower window height, insulation under windows and in the crawl space. The school's energy use before and after rebuilding has been calculated with the calculation program, Vip-Energy 1.5.5.Calculations of energy use for the school with windows on U-value, 0.9 and 0.7 have also been done. The replacement of windows has been studied from a cost perspective. The conclusion is that the exchange of heat and ventilation system was the biggest contributor to reduced energy use on Bokelundskolan.
Varmhållen och kyld skolmat : En jämförelse med fokus på energianvändning mot bakgrund av livsmedelssäkerhet och näringsretention
The aim of this report has been to investigate the use of electricity energy before and after a conversion of foodservice. The ambition was also to highlight the food safety and the retention of nutrients in relation to the conversion. The methods being used were qualitative interviews, case studies, study visits and literature. The equipment and the use of energy was the same in 2008 as in 2011 for hot-holding of the tested component, sauce with ham. The chilled system used more than three times the energy and cost for one portion than one portion in the hot-hold system.
Framtidens energilagring : en studie av befintliga samt potentiella metoder fo?r lagring av fo?rnybar el pa? ett ha?llbart sa?tt
In today?s society there is an increasing demand for renewable energy sources such as sun and wind power. These sources are intermittent, and energy storage is therefore needed to ensure a constant power supply. This report compares pumped hydro energy storage (PHES), compressed air energy storage (CAES), flywheels, batteries, super magnetic energy storage (SMES) and hydrogen energy storage.The opportunities for further development are limited for PHES and CAES in comparison with the other technologies. Lithium-ion batteries and hydrogen energy storage are considered to have the most potential in the future.
Konsumentvänlig Energibesparingsmodell : Ett verktyg som hjälper småhusägare att sänka sina energikostnader
Energy awareness is growing among the Swedish population and a one?to?two-family dwelling can save energy. The purpose of this paper is to design a tool that helps these home owners reduce their energy costs.The paper develops a model that gives them an indication of how much energy they can save. For the majority of homeowners, the next step in the quest to reduce theirs is most likely an energy audit. Therefore, information to help home owners to get a good energy audit performed is included in the model.A prototype running the operating system iOS is created and validated against existing models, as well as an energy audit. .
Småskalig säsongslagring av solenergi för uppvärmning av bostäder : Simulering av lagerutformning och konsekvensen av adderade uppvärmningsbehov motsvarande en pool och ett atrium
The sun is a huge energy source with great potential of providing energy to the heating of homes and other buildings in an environmentally sustainable manner. In order to provide buildings with energy from the sun it is necessary to transfer the energy supply over time to when the demand arises. By storing the heat in a seasonal storage, solar energy from the summer can be used in the winter when the demand for heating is greatest.Today's existing plants are mainly in Europe and particularly in Germany. These facilities are designed to supply heat demands greater than 400 MWh and covers about 40-50 % of this need which consists of energy for space heating and domestic hot water. How much of the heat demand that is covered, the solar fraction, is partly due to losses from the storage which in turn is connected to the surface area of the storage.
Energieffektivitet och kvalitet på inomhusluft i radon förorenade bostadshus
To build a sustainable future should we first understand that; every aspect of our daily lives can affect the environment. It?s important that we take responsibility for understanding how we impact the environment and change our actions accordingly. The worlds total energy consumption equivalent to 80 million MWh / year. This corresponds to about 220 million MWh / day.Energy consumption is one of the main reasons for increased greenhouse gases when the reduction of this consumption has a great demand worldwide.In order to prevent the energy that consumed the buildings must be energy efficient but there is a conflict between radon ventilation and energy conservation in a building, given that ventilation can consume as much energy (currently 29-59% of energy-efficient houses use), especially in a cold climate as in Norway.
En energiutredning och miljöklassning av Hemsta 12:16
The purpose of this study was to implement an energy analysis and environmental evaluation of the property Hemsta 12:16 in Gävle. Based on two different methods, Energy Balance calculation and Environmental Building, the result of the property's energy use, energy performance and environmental impacts are presented. Except that, measures to reduce final energy consumption are presented. The proposed measures can reduce energy usage by 100 400 kWh / year, which represents a decrease of 18% of the present energy usage. This would represent a total savings of 63 000 SEK per year. In addition, the environmental performance is improved by adopting the suggested measures..
Verifiering av beräknad energiprestanda för flerbostadshus byggda år 2007-2009
The building industry consumes approximately 40 % of the total energy consumption in Sweden, where the using stage is dominating with 80 %. There is a lot of work in progress to reduce energy use in the building industry, and the demands from authorities regarding energy use increases. As a part of this work Building and planning department of Sweden has established a requirement that has been applied since 2006, and restricts a maximum energy use for buildings.The requirement includes that an energy simulation must be done in advance to demonstrate that it is possible to meet the demands.Reality is however more complex than an energy simulation program, that frequently underestimates the energy use of buildings. The purpose of this thesisis to study and analyse deviations between estimated and actual energy use in modern apartment buildings. The study includes four apartment buildings in Stockholm, Gothenburg and Jönköping that were built in 2007-2009.
Utveckling av Mätmetoder för Färdmotstånd
The student project Elba at KTH started in 2011 and is a project where a battery driven prototype car is developed. The vehicle competes in Eco Shell Marathon in Rotterdam, Holland. In this competition the vehicle that travels a certain distance including several starts and stops with the lowest energy consumption wins. To minimize the consumption is therefore very important, which requires knowledge of the vehicles Energy losses.A vehicle's Energy losses depends on several factors and can be divided into the powertrain efficiency and the driving resistance. The driving resistance can then be divided in to rolling and air resistance, if smaller losses like vibrations are ignored.
Energikartläggning och energieffektiviseringsåtgärder i Zoologen på Göteborgs Universitet
The question of excessive global energy use needs to be solved. All energy production and usage have negative environmental impacts, which are best solved by reducing energy consumption and by using energy more efficiently. A large part of the Swedish energy use is concentrated to the building sector and to reduce the total energy consumption real efforts need to be made to make buildings more energy efficient.The aim of this study was to investigate how energy is used in one of Göteborg University?s buildings and to find measures that can be taken to improve its energy efficiency. The chosen building Zoologen, is used for research and education.The main method of the study is computer simulations of the present building and of possible energy reducing measures to be made in the future.
Expansionsmaskiner istället för strypventiler - en effektivisering
In Uppsala CHP Plant, there are six pressure reducing valves to reduce the pressure from 15 to 3 bars, before six absorption heat pumps. During the process the energy is conserved but losses occur in form of exergy. The aim of this thesis is to reduce the losses of exergy. This can be done by letting turbines replace the pressure reducing valves.In this thesis an investigation has been done of the conditions today, the conditions after the change from pressure reducing valves to turbines and a comparison of three different types of turbine solutions. The three examined solutions are one turbine, several helical screw expanders and several small turbines in parallel with asynchronous generators.The six absorption heat pumps have been divided into two groups; one group of four and one group of two absorption heat pumps.
En energieffektiv byggarbetsplats : En studie av Skanskas bostadsprojekt
The construction industry has demands on energy use in permanent buildings. How much energy that is permitted to use during the time the building is produced has no requirements. The purpose with this study is to learn how far Skanska has come with the work of making the building site more energy efficient.A literature study has been performed in the beginning of the study to survey what energy efficient arrangements that can be applied and how they operate. Using site visits and interviews the situations on the building sites have been studied as well as the energy efficient measure that are in use.Skanska has come a long way with the work of energy efficient building sites and they keep improving. They have improved half of their cabins so they use 50 % less energy.
Solvärme med säsongslager i Lyckebo
The purpose of this thesis is to investigate and clarify the facts surrounding one of Vattenfall's district heating plants; The "solar field" and associated rock cavern in Lyckebo, Storvreta. The plant was built in the '80s by the formerly municipal utility,Uppsalakraftvärme AB, as an experimental building. A ground water filled cavern would serve as seasonal storage of solar heat from an adjacent solar field. Since both the energy company and the facility itself has undergone major changes over the past 30 years, there was a great need to gather facts in order to provide a picture of its current condition and potential for continued use. The thesis investigates the plant's history and problems with the rock cavern losses, and how the operation developed. It also presents the calculations regarding the possibilities of again supplementing the facility with solar energy - which is not the case today - as well as the economic conditions for it. Regarding a re-launch of solar energy, primarily a concentrating solar collector has been studied, as it has the advantages of an integrated control system.
TCP/IP i taktiska ad hoc-nät
TCP (Transmission Control Protocol) is a transport protocol designed for the wired Internet. In wireless networks packet losses occur more frequently due to the unreliability of the physical link. The main problem is that TCP treats all losses as congestion, which leads to a lower throughput. Ad hoc networks are multihop wireless networks of mobile nodes, where each node can allow other packets to pass through it. Topology changes often occur and may lead to packet losses and delays, which TCP misinterprets as congestion.