The design of environmental extensions in the input-output analysis is based on the user-side perspective and only focuses on commercial energy supply and use, which implies that its spatial and temporal boundaries are limited to technical energy extraction and use. Moreover, the literature that discusses the donor-side perspective to supply and use-extended footprint models are in its infancy. This study introduces an emergy-evaluated supply-extended and use-extended carbon footprint models for the city of Vienna and then compares and assesses differences in results for their empirical and conceptual implications. Our results show that the ranking of footprints of final product categories is sensitive to the evaluation method and that products of extractive and manufacturing industries (agricultural and chemical products ) differ by more than 10% depending on whether emergy or carbon evaluation is chosen. The emergy-based comparison further reveals that for products of extractive industries difference between use and supply extension results can be more than 20% as opposed to carbon-based comparison with the difference between supply and use extension results for services not even amounting to 5%. We, then discuss conceptual differences between emergy and traditional carbon-evaluated extension designs and conclude that a more accurate estimation of the total environmental burden of each sector in an urban economy can be archived in the first step of the allocation procedure used in emergy-evaluated used-extension design (allocation direct energy use of fuels to final consumption to households, government, capital formation, and exports) is added to emergy-evaluated supply-extension results. Such use of these models provides a basis for a comprehensive understanding of environmental support to production processes and economic activities and, therefore, can assist policymakers in assessing the implication of their local decisions on the larger scale of socio-economic and life-support systems.