Sökning: "agricultural systems"

Visar resultat 1 - 5 av 419 avhandlingar innehållade orden agricultural systems.

  1. 1. Electric autonomous tractors in Swedish agriculture : A systems analysis of economic, environmental and performance effects

    Författare :Oscar Lagnelöv; Sveriges lantbruksuniversitet; Sveriges lantbruksuniversitet; []
    Nyckelord :LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES; LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

    Sammanfattning : Use of battery-electric vehicles has become common in different sectors, as a measure to reduce greenhouse gas emissions. Driveline electrification in agricultural machinery could reduce emissions and increase driveline efficiency, but implementation has been hindered by the low energy-carrying capacity of batteries compared with conventional fuels. LÄS MER

  3. 2. From waste problem to renewable energy resource : exploring horse manure as feedstock for anaerobic digestion

    Författare :Åsa Hadin; Ola Norrman Eriksson; Karl Hillman; Nils Ryrholm; Jaana Sorvari; Högskolan i Gävle; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; horse manure; environmental systems analysis; energy systems; renewable energy; environmental impact; anaerobic digestion; biogas; biofertilizer; systems perspective; bedding; incineration; composting; horse manure utilization;

    Sammanfattning : A sustainable energy system requires, according to energy policies, reduced emissions of greenhouse gases, increased ratio of renewable sources of energy and more efficient use of energy. Horse manure could be regarded as waste, but also as a resource for renewable energy and plant nutrients. LÄS MER

  4. 3. Food or fuel? : trade-offs between food and biofuels globally and in small-scale organic agriculture

    Författare :Sheshti Johansson; Sveriges lantbruksuniversitet; Sveriges lantbruksuniversitet; []
    Nyckelord :LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES;

    Sammanfattning : There are great expectations on agriculture to provide both food and fuels in the future. Previous attempts to estimate the global bioenergy potential have produced varying results, indicating major uncertainty. This thesis investigated the global theoretical 'potential', or limit, for biofuels based on current agricultural systems. LÄS MER

  5. 4. Recycling plant nutrients from waste and by-products : a life cycle perspective

    Författare :Johanna Spångberg; Sveriges lantbruksuniversitet; Sveriges lantbruksuniversitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES;

    Sammanfattning : Chemical fertilisers contribute to greenhouse gas emissions, fossil fuel use, use of non-renewable phosphate rock and a flow of reactive nitrogen to the biosphere, exceeding the planetary boundaries. Recycling of plant nutrients from waste and by-products from society would reduce the use of chemical fertilisers. LÄS MER

  7. 5. Climate Impact and Energy Balance of Emerging Biorefinery Systems

    Författare :Hanna Karlsson Potter; Sveriges lantbruksuniversitet; Sveriges lantbruksuniversitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES;

    Sammanfattning : Use of fossil fuels is the main contributor to anthropogenic emissions of greenhouse gases (GHG). Biorefineries, which are facilities that produce a set of valuable products from biomass, have been suggested as alternatives to fossil refineries, for the production of fuels, chemicals and materials. LÄS MER