Digitized renewable energy systems promise to promote accessibility and participation in energy markets by end users. While some use cases unlock new potentials for certain groups in society, they are not easily available for all. Unequal access to digital infrastructures and chances for participation, as well as differing digital and energy literacy, could inhibit vulnerable populations from participation in several use cases. This review lists use cases in smart energy systems from a user perspective, and pinpoints social strata that are at particularly high risk of being marginalized. Based on respective preconditions for participation, we deduce hypotheses for social marginalization risks. Sociodemographic factors such as income, level of education and age are critical for participation. In addition, digital literacy depends on socioeconomic status: A higher socioeconomic position leads to better digital literacy. End users’ environmental awareness and trust are also decisive for participation in the digital renewable energy transition. Hence, end users from certain social milieus with less environmental awareness and stronger institutional mistrust, who are less integrated into the local community run higher risks of being further left behind. Looking through the lens of vulnerable end users, we find that the narrative of social inclusion is confronted with the conceivable social exclusion or marginalization. Consequently, energy policies should generally be scrutinized for more social justice and designed accordingly.