Abstract—Energy efficiency of computing devices has
become a dominant area of research interest in recent
years. Most previous work has focused on architectural
techniques to improve power and energy efficiency; only
a few consider saving energy at the algorithmic level. We
prove that a region of perfect strong scaling in energy
exists for matrix multiplication (classical and Strassen)
and the direct n-body problem via the use of algorithms
that use all available memory to replicate data. This means
that we can increase the number of processors by some
factor and decrease the runtime (both computation and
communication) by the same factor, without changing the
total energy use.