Within the context of an energy transition towards achieving a renewable low-impact energy consumption system, this study analyses how bottom-up initiatives can contribute to state driven top-down efforts to achieve the sustainability related goals of (1) reducing total primary energy consumption; (2) reducing residential electricity and heat consumption; and (3) increasing generated renewable energy and even attaining self-sufficiency. After identifying the three most cited German bottom-up energy transition cases, the initiatives have been qualitatively and quantitatively analysed. The case study methodology has been used and each initiative has been examined in order to assess and compare these with the German national panorama. The novel results of the analysis demonstrate the remarkable effects of communal living, cooperative investment and participatory processes on the creation of a new sustainable energy system. The study supports the claim that bottom-up initiatives could also contribute to energy sustainability goals together within the state driven plans. Furthermore, the research proves that the analysed bottom-up transitions are not only environmentally and socially beneficial but they can also be economically feasible, at least in a small scale, such as the current German national top-down energy policy panorama.