The outcomes of a survey analysing public acceptance of biomass cogeneration heat (and power) plants (BCH(P)P's) of 3,000 Bavarian households in the neighbourhood of ten BCH(P)P's are reported in this paper. Acceptance was measured in two different distances to plants in order to check for the so-called "Not-in-my-backyard effect" (NIMBYism): Nearby regions (0-500 m) and distant regions (2,000 m plus). The survey results show that public acceptance is better than expected and interviewees only feel very little disturbed by BCH(P)P's. The motives of plants' proponents fundamentally differ from the motives of the few opponents, who mainly raise egoistic reasons, whereas proponents have a look on their regions' welfare respectively the well-being of the planet. Furthermore, there are huge deficits in residents' information. There is only little evidence for distance-related NIMBYism in case of the surveyed sites. In contrast, aspects like "heat-delivery", "attitudes towards renewable energies" and "degree of information" have significant impact on the acceptance of the respondents. Besides the factors "plant-size", "attitudes towards plants in the planning phase" and "runtime" (regardless the acceptance status in the planning phase) seem to affect public acceptance for years. Furthermore, public acceptance tends to change to an intermediate level - even if acceptance in the planning phase was high.