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1177 Uppsatser om Forest fuel - Sida 1 av 79
Skogsbränsleuttag vid förstagallring och dess påverkan på beståndsutveckling : simulering i Heureka med olika skötselprogram
Stands where pre commercial thinning has been ignored or inadequate often tend to have high stem density and low average diameter when they reach heights of thinning. In such stands, it can often be expensive to do a conventional pulpwood harvest as a first thinning. This study investigates the development of the stands and the economic outcome of Forest fuel extraction, or a combined harvest as alternatives to the ordinary pulpwood harvest. Simulations in Heureka StandWise were performed for two thin and dense stands, which were constructed by data from the Swedish National Forest Inventory. The simulations show that the extraction of Forest fuel in first thinning at an early stage can provide higher net revenue compared to conventional pulpwood harvest at the same time or later.
Sveaskogs möjligheter att utveckla trädbränsleverksamheten i Västerbotten och södra Norrland :
This final thesis is initiated by the wood fuel department at the Swedish forest company Sveaskog as part of a project which also involves two other final thesises. The overall goal of the project is to investigate Sveaskog´s possibilities to produce and sell different wood fuel assortments in Västerbotten and the southern parts of Norrland. The aim of this thesis is to investigate how much wood fuel Sveaskog can produce in the area during the next five years and what that would cost. Furthermore the thesis will investigate the total possible supply of wood fuel from all other possible producers in the area. Treated assortments are forest residues from final fellings, whole trees from direct wood fuel thinnings, non industrial wood and industrial by-products from sawmills.
The main effort to investigate Sveaskog´s production possibilities has been made to calculate the possible annual amount of forest residues and fuel from wood fuel thinnings that can be produced.
Träddelsuttag eller massavedsuttag i förstagallring?
The purpose of this study is to compare the economic differences between withdraw of Forest fuel and withdraw of pulpwood in first thinning, to see which method gives the maximum profitability (income - cost). Another purpose is to investigate the economic impact of the thicket cleaning.
The study compares four different methods: i) pulpwood output with thicket cleaning, ii) pulpwood output without thicket cleaning, iii) Forest fuel output with thicket cleaning and iv) Forest fuel output without thicket cleaning. The study was conducted in a 30-years old stand, dominated by spruce, outside Harg in Uppland.
The method that generated the best economic net income was pulpwood without thicket cleaning. It generated a positive net of 1,383 SEK per hectare. Forest fuel output without thicket cleaning also generated a positive net in 720 kronor per hectare.
Tillvaratagande av GROT i skärgårdsnära miljö :
The main aim of this study was to investigate and compare different methods for the extraction of Forest fuel from environments close to an archipelago. The study was based on relevant literature and published reports as well as personal communications.
Forestry has traditionally been characterized by intense efforts to rationalize and mechanize the cutting technique used for timber and pulpwood. In line with the increasing importance of forestry, more concentrated efforts can be expected in the area of techniques and methods, especially for the above-mentioned product lines.
In Sweden, forestry is of major importance and the Swedish economy and standard of living have mainly been created based on the revenues generated from it. Thus, it is vital that Swedish forests are harvested in an efficient and responsible manner.
The demand for biofuel is growing and today accounts for 15% of total Swedish energy production, a share that will probably increase.
This study is based on three research questions, which are described under the heading of Aim. The results reveal that the most profitable method for handling Forest fuel is the traditional one, which is also the most commonly used method in southern Sweden, namely the stockpiling of logs in a clearing by means of forwarders followed by splintering at the place from where they will be distributed.
Today, the high cost of barge transport required for the extraction of Forest fuel in an archipelago environment renders such operations unprofitable.
Skogsmaskiners bränsleförbrukning :
This report is a thesis work for a B.Sc. in Forestry exam at the School for Forest Engineers, SLU. The aim of the work was to compare fuel consumption during work in practical field conditions with a standardized method developed by Skogforsk (The Forestry Research Institute of Sweden), (Brunberg, 2005) for harvesters and forwarders from different manufacturers and of different sizes in order to promote the development of more fuel efficient machines.
Two studies were carried out.
- Statistics of fuel consumption were collected.
- An inquiry was sent out in order to get more detailed information of different aspects influencing the fuel consumption.
The studied machines were divided into two classes, large machines (> 150 kW), and average size machines (100 ? 150 kW), and of the manufacturer Timberjack and Valmet.
Our results shows a 15 % lower fuel consumption for average size harvesters and an 8 % higher fuel consumption for large harvesters compared with Skogforsks model.
Ekonomi vid uttag av långa toppar som skogsbränsle i slutavverkning :
The market for biofuels from the forests have had a positive development and the job initiators for this master´s thesis wanted to examine the profitability of a method for harvesting Forest fuel, which was unfamiliar to them. The method was the ?long tree tops-method?, here called the LT-method.
The LT-method is characterised by the fact that timber is harvested as the only roundwood assortment while the rest of the stem, which in other cases would become pulpwood, is harvested as Forest fuel together with the logging residues. The method is based on the assumption that advantages in handling of the Forest fuel assortment such as increased load weights for forest hauling and truck transportation, should compensate for the lower price for pulpwood when sold as Forest fuel.
The aim of the study was to compare the profitability of the LT-method with the GROT-method (harvest of timber, pulpwood and logging residues) and conventional logging without any harvest of Forest fuel, and aslo to try to identify factors affecting the profitability of the different methods.
Lokal logistikoptimering för ENA Energi i Enköping
The cost for forestry logistics in Sweden is about 25 percent of the total cost of getting the raw material to industry (Anon., 2010). There might be much to gain by taking a look at your supply chains on the logistic side in your company. In this report the logistic chains by Mellanskog for ENA Energi AB in Enköping has been looked in to. ENA Energis plant is a combined power and heating plant and about 99, 5 percent of their fuel consisted of bio energy in year 2009 (ENA Energi, 2011, länk A).
The main purpose with this report is to look at three questions:
1. How does the supply chain look today? From forest to industry.
2.
Etanol : ett hållbart tankande eller ett kortsiktig tänkande?
Ethanol fuel is a biofuel, which been widely reported in the public debate and on the fuel market the last years. Ethanol is sold as both E85 and as a five percent admixture of all petrol sold in Sweden. Research studies on ethanol fuel often focus on environmental issues surrounding the production and utilization of ethanol as a fuel, and omits the private and business aspects of the subject. The purpose of this study is to illustrate the economics of ethanol as a fuel. How the Swedish market for ethanol is and how it evolved over time and what the future prospects are.
Produktivitet och lönsamhet vid skogsbränsleuttag i klena gallringar : en tidsstudie av Vimek 608 BioCombi i contortabestånd
The annual demands for Forest fuels increases in Sweden. At present, large unutilized biomass resources is found in young, dense forests from which about five million oven-dry tonnes (ODt) (23 TWh) could annually be extracted as Forest fuel. But harvesting small trees give high logging costs and new cost-efficient harvesting techniques are therefore required. The aim was to study the productivity of Vimek 608 BioCombi in Forest fuel thinning of Lodgepole pine and to calculate the economy of the harvesting and estimate the thinning quality. The time study was performed in Åmarken in the county of Västerbotten.
Optimalt råvarulager för biobränsleföretaget :
This report was written as a final thesis within the Department of forest economics at the Swedish University of Agricultural Sciences as a completion of the M.SC Forestry programme. The aim of this study was to create a model that, with respect to given stock levels, temperature, fuel usage and fuel price, would identify the optimal levels for purchase of bio fuels, optimal levels of incineration of bio fuels and the sum of the present values of all costs. The model would be applicable for a larger district heating plant.
Data regarding temperature were received from SMHI. Information considering fuel prices was taken from the Swedish Forest Agency and the facts about fuel usage were collected from a large district heating plant, located in the southwest of Sweden. For the temperature, a sinus curve was adapted to describe the temperature over a year.
Competition for forest fuels in Sweden : exploring the possibilities of modeling forest fuel markets in a regional partial equilibrium framework
This thesis project focuses on the need for better tools for analyzing competition for Forest fuels in Sweden, in particular how policy measures may influence the market and involved actors in different regions of Sweden. Raw materials from the forest have for long constituted important inputs in the Swedish forest industry. Today some of these raw materials are increasingly used as inputs also in bioenergy production, largely driven by bioenergy promoting policies, and there are signs of increased competition for Forest fuels which may have various and uncertain effects on the industries in question. The thesis project explores the possibilities to adapt previously used forest sector equilibrium models into a new model suitable for analysis of Swedish Forest fuel markets, called the Swedish Forest Sector Trade Model (SFSTM). The approach takes into account regional differences in supply and demand for 23 types of products produced and/or used by eight types of producers, plus consumers, in five different regions (four Swedish and one international).
Produktionsskillnader vid olika antal sortiment
This study is done together with Sydved AB in the summer of 2012. The purpose of the study is to analyse how different quantity of assortments influence the production for forwarders and harvesters with multiple tree handling aggregate in thinning, by different tree volumes. To make this analyse a time study was performed where three entrepreneurs work has been analysed. Beside the analyse, of different quantity of assortments, has also been analysed how the tree volume and a Forest fuel assortment effect the production.
The result of this study shows that the quantities of assortments have a significant meaning for the production. The biggest differences are most distinct between one and three assortments in the smaller tree volumes where production goes down if the quantity of assortments increase.
Bruka utan att förbruka - när andra intressen än ekonomin får styra
To have a forest area close to the city is of great importance for the city population?s well being. Children develop their motor skills, concentration and imagina-tion and the adults have a place to shake of the stress from work. Forest areas are used to exercise at, play in and to find a moment of peace and silence.
The urban forest and the old farming pastures at Markussonvallen and Per-Isakssonvallen already has natural assets worth to preserve and a great potential to create more. The goal is to develop a forest with a variation of tree species and ground vegetation that will appeal to the human senses and different animal species such as birds, insects etc.
Skogsbränsledrivare i klen förstagallring med contorta
The aim for the study was to examine a harwarder´s (combined harvester-forwarder) productivity when harvesting Forest fuel in first thinning stands that contains Lodgepole pine and calculate the economy of the harvesting work and estimate the quality of the thinning . The field study area where located near Arvån, about 15 kilometres south ?east from the city of Lycksele. The field studies were taken place in three different stands. All tree stands had the same tree age, but the tree species combination and the density varied.
Vätgas och bränsleceller : Ny energi för Försvarsmakten?
The purpose of this paper is to identify the current status of fuel cell technology and to establish whether said technology is mature enough to be implemented into the Swedish Armed Forces. The question to be answered in this paper is as follows: Can hydrogen gas and fuel cells be used as an alternative source of energy within the Swedish Armed Forces?This paper is based on theoretical studies and reports from prior research done on fuel cells. By studying these facts a predictive answer has been obtained. The answer I have come to, is that the maturity of fuel cell technology is currently inadequate for the Swedish Armed Forces to implement, especially considering its harsh working conditions..