Decentralized energy storage systems (ESS) are a promising means to more effectively match the supply and demand of fluctuating renewable energies. In most countries, however, ESS market share is small and whether or not the technology will attain a critical market share is subject to homeowners' investment decisions. For policy and industry alike, it is of particular interest to identify factors that drive ESS adoption. Empirically addressing this question, we hypothesized that the factors autarky and autonomy aspirations crucially determine ESS adoption decisions. In two studies (Ntotal = 489), sketching future decentralized energy scenarios, we found evidence for the importance of both factors for homeowners' evaluations of the technology. However, only autarky significantly affected homeowners' willingness to pay extra for ESS, in that homeowners invested more in the technology when autarky was higher (Study 1) or autarky benefits were emphasized (Study 2). In accordance with concepts aspiring to optimize energy flow on the low-voltage grid level (e.g. Smart Neighborhoods), we additionally examined the influence of autarky and autonomy aspirations on homeowners' willingness to exchange self-generated energy within a local energy network. Results showed that emphasis on autarky increased the subjective value of self-generated energy, decreasing the likelihood of peer-to-peer energy trading.