  We consider two possible flat space limits of three dimensional $\mathcal{N}
= (1,1)$ AdS supergravity. They differ by how the supercharges are scaled with
the AdS radius $\ell$: the first limit (democratic) leads to the usual
super-Poincare theory, while a novel `twisted' theory of supergravity stems
from the second (despotic) limit. We then propose boundary conditions such that
the asymptotic symmetry algebras at null infinity correspond to supersymmetric
extensions of the BMS algebras previously derived in connection to non- and
ultra-relativistic limits of the $\mathcal{N}=(1,1)$ Virasoro algebra in two
dimensions. Finally, we study the supersymmetric energy bounds and find the
explicit form of the asymptotic and global Killing spinors of supersymmetric
solutions in both flat space supergravity theories.
