The dairy cow?s ability to resume estrus after calving and to conceive is affected by their metabolic status after calving. For high yielding cows there is a high risk that the feed intake will not be sufficient to cope with the increased energy demands after calving, and the cow will end up in a state of negative energy balance. Energy balance can be measured in various ways, for example by body condition score or by plasma concentration of several metabolic hormones and metabolites. After calving, endocrine pathways stimulate tissue mobilization; insulin signaling is blocked, the concentration of insulin-like growth factor-1(IGF-1) and leptin decreases, and the concentration of growth hormone (GH) increases.

When the Swedish Forestry Act was changed in 1994, brushing of young stands became non mandatory. Since then the annual need for brushing in the country has increased by about 100 000 hectares per year. In later years the price for biomass energy has increased to the same level as pulp wood. The high price on biomass energy and the large areas of stands in the need of brushing has created a new market with its own technical, economical and environmental conditions. There is a development of various techniques to manage the forestry stands with late brushing.

This Master degree project has been performed at the Braviken paper mill on papermachine 53 (PM53) which produces newsprint paper. The current economic situationhas contributed to declining demand for newsprint, which means it is extra important tobe competitive by High energy efficiency. Particularly as energy prices are expected torise when the economic growth returns.One way to increase energy efficiency is by reducing the water use in paper and pulpmills and consequently save energy through reduced heating of water. The thesis's maintask is to evaluate whether a water purification plant (microflotation plant) forpurification of process water in PM 53 is profitable. The microflotation plant enablesreuse of warm process water instead of losing the energy to receiving waters.

This master?s degree project concerns the combination of a multi dwelling passive house with solar energy for the generation of electricity and domestic hot water (DHW). Different alternatives with either solar thermal systems or photovoltaic (PV) systems are compared with two reference alternatives producing DHW from electricity or district heating. The economical comparison uses a life cycle cost (LCC) perspective based on the present value of expenditures for investment, energy and annual operating and maintenance.The energy yields from the solar energy systems were calculated by hand and with simulation software. Calculation and dimensioning of PV systems were carried out with a software called PVSYST.

The aim of this thesis is to develop a new business model for district heating and cooling firms which can contribute to a stabilization of the Swedish national energy system. The business model is developed for a district heating and cooling firm and is exemplified with Fortum Heat. The theoretical investigation around the topic creates a rigid base for following qualitative empirical studies. Osterwalder?s canvas for business model generation is used together with a Casual Loop Diagram to identify a number of business opportunities which stabilizes the national energy system.

Swedish energy policy aims to increase the use of energy from renewable sources and this should be done in a safe, environmentally and sustainable manner. According to the Energy Agency the use bio-fuel increased by 73% between 1990 - 2006. Stands with high share of slash are often located on areas with high productivity which often are located on soils with poor bearing capacity. This will increase traffic on susceptible soil leading to increased ground damage. To reduce the risk of ground damage at slash-forwarding, ground protection is needed.

This study concerns the energy future of the county of Stockholm up until 2050 and describes how the energy consumption can be compared to today with the use of scenario methodology. Within energy future studies the backcasting approach is well known and has been put to use in this study. Due to the characteristics of backcasting the study is self-fulfilling, i.e. the future energy scenarios presented in this study satisfy the targets set up in this study. In the light of what may be the largest challenge of our time ? the climate change - the aim of this study is to describe how the energy consumption in a fossil fuel free Stockholm county in the year of 2050 may be.

Swedish energy policy aims to increase the use of energy from renewable sources and this should be done in a safe, environmentally and sustainable manner. According to the Energy Agency the use bio-fuel increased by 73% between 1990 - 2006. Stands with high share of slash are often located on areas with high productivity which often are located on soils with poor bearing capacity. This will increase traffic on susceptible soil leading to increased ground damage. To reduce the risk of ground damage at slash-forwarding, ground protection is needed.

Efficient energy use in the housing sector is crucial for achieving a sustainable society. The expansion of this sector only represents a fraction of the existing houses, hence it?s within the existing houses the potential for energy savings lie. This potential has been analyzed in order to determine if it?s possible to cut the current energy demand in half.

As demand for renewable energy is increasing rapidly, the market for biomass pellets is expected to continue to grow in the near future. Most of the new raw materials that are discussed for pellet production have one thing in common; the production costs will increase compared to using traditional raw materials such as sawdust and planer shavings. The aim of this thesis is to investigate to what degree increased use of new raw materials for pellet production will affect the general pellet prices in Sweden and to survey what plans Swedish pellet producers have concerning new raw materials. To investigate the raw material situation of the Swedish pellet producers an industry survey was performed. Literature studies were also made on previous research in the subject field. Calculations of the production costs for pellets were done for the raw materials sawdust, wet sawmill chips and energy wood respectively. New raw materials are already used by the large-scale pellet producers in Sweden.

Interest in alternative energies is high in Sweden today, particularly in the agricultural sector. According to the Swedish lantbruksbarometern (2009), almost all respondents consider the use of some form of alternative energy from the farm. While interest in alternative energies is large, attention to the alternative energy straw has fallen and is almost nowhere mentioned in the literature today. Three years ago, in the Lantbruksbarometern nearly 44% of the farmers would be willing to invest in straw as heating system on the farm. How do the farmers decide to invest in alternative energies? With this information a problem is presented for this paper.

The company Sol & Energiteknik wanted to examine the possibility to make a standardhouse totally energy independent. Based upon this I have, during the spring of 2007,examined the possibilities available at the market today through litterature studies, contactwith several companies and reading reports at the internet.The first thing to examine has been to determine the energy consumption for a standardhouse, and find out if there are better technologies to be used for energy conservation.My conclusion in this matter is that there are possibilities today for building a house moreenergy efficient.When I had reached the point at which my design for the house was decided, I also hadto choose the different products to use to produce energy as well as to store that energy.To produce heat and electricity to the house I decided to use a wind turbine and a solarwater heater.The most difficult part of designing a house that is energy independent is that theproduced energy must be stored somehow. Storing the heat is relatively easy beacuse theheat can be stored in a large water tank. The electricity is a bigger problem beacuse itmust be stored in batteries, which today are too expensive to be used in a standard house.In the future producing and storing hydrogen might be used to produce electricity, buttoday that technology is both expensive and not tested enough.My final conclusion is that a standard house can not be built to be totally energyindependent today, unless it is very expensive to connect the house to the electricitynetwork. As an alternative solution I came up with a proposal for a house which isconnected to the electricity network and have some amount of own produced energy.This house prooved to be a good investment if you choose to build it today, and it couldbe a very good investment in the long run beacuse energy prices increase every year..

Global warming is a huge issue that humans have contributed to through over-exploitation of natural resources and extensive usage of fossil fuels. Now more than ever, we need to embrace a recycle thinking and reuse our waste, for example through producing biogas from our food waste. The purpose of this report was therefore to identify the energy usage and emissions resulting from the biogas chain which spans from Solna Stad to Uppsala Vatten. Furthermore, potential efficiency improvements were to be identified and proposed. This report focused mainly on the first part of the biogas chain that includes the collection of the food waste and the reloading process.

This paper goes through solar energy and what uses it has. It is also a guide in the choice of solar collectors forthe real estate that I have drawn for the thesis work.Solar energy is a renewable source of energy from the Sun's light. Energy can be used to produce both heat andelectricity through solar collectors and solar cells. Some of the benefits of solar energy is that it is completely freeto extract, environmentally friendly and virtually maintenance-free. Disadvantages are that the technology isexpensive, does not cover the entire energy needs and takes a long time until it pays.

The goal of this paper is to find out how solar cells can improve energy efficiency on-board M/S Sydfart. The paper is based on a number of energy measurements on board the M/S Sydfart. The solar surface is calculated by measuring the available space for installing solar panels. Global radiation data is taken from STRÅNG's database, the data is then used to calculate the theoretical power produced by the solar cells. Energy efficiency is analysed in two ways.