The dominant energy sources on conventional farms in the developed world are diesel oil (to power tractors and other self-propelled equipment) and electricity (to provide light, heat and refrigeration; and to power electric motors to run milking machines, animal feeding systems, ventilation fans, water supply and irrigation systems).
Clearly additional investment in research and development is required to render the autonomous power supply options as economic and user-friendly as possible. Also, it should be noted that the purchased electricity supply, although not autonomous, could still be (at least in part) generated from renewable power sources. From a national perspective, renewable alternatives to diesel fuel for mobile equipment (e.g. oilseed fuels) (see also, Energy Sources: Renewable and Non Renewable) may also be considered as autonomous power.