The advantages and limitations of renewable energy have been discussed in various studies with an aim to increase its participation within the national energy mix. Options are being sought to encourage its use, mainly with the deployment of large-scale installations, which in many cases are farther from the centers of consumption. Such approach does not reduce neither the losses associated with transportation nor the lack of empathy of urban society with the externalities produced in areas placed far from the cities. As an alternative, it proposes to raise energy self-supply by promoting the use of endogenous resources that a city may possess. It was determined that there are several technologies that are available and that can be applied in a city. In spite of the fact that its implementation can be conditioned by the existence of the resource, costs or acceptance of the community, it is urgent that urban planners include the use sustainable energy, in order to meet future shortages of resource and adverse environmental phenomenon. With this proposal we conclude that using the approach of urban metabolism it is possible to promote the use of available renewable energy resources at cities. Based on a general approach, it is shown that it is possible to contribute to change a metabolic linear model to a metabolic circular model.

Expectations against environmental degradation, including future effects of global warming, require changes in the way how the city is conceived. As an essential, is necessary that public policies and organized planning to consider concepts related to energy supply with the resources that have the cities. Given the enormous pressure of the cities on the environment, the proposed changes are in fact an opportunity to promote sustainability. In a previous study, eleven technologies that use resources available or that come from the cities was determined. It was established that with the widespread use of these technologies, it possible reduce flows from energy carriers that require a city. These energy carriers may be electricity or fuel, and are used for producing heating, power, lighting or data process. Of the technologies described, eight can be used for electricity generation: biomass, biogas from digester, biogas landfill, waste incineration, tidal, wind, small hydro and photovoltaic. The possible use of one or other technology depends not only on the existence of the resource. Is necessary, take in count, technical, economic, social or environmental factors. This research proposes to use multicriteria techniques to analyze holistically the most appropriate option for promoting energy renewable in a particular city.