[Comparison of the economic competitive power of seven alternative energy technologies in the supply of heat and electricity to farmsteads [oil burners, straw burners, pigsty heat pumps, windmills, biogas systems, composting]]

calentamiento chauffage compost composts costos costs danemark denmark dinamarca electricidad electricity energia energia eolica energie energy energy sources habitat rural heating paille paja rural housing straw vivienda rural wind power