Physics tells us that at the microscopic level the evolution of a (micro-) state is reversible, ie deterministic both forward and backward in time. In contrast, our best models of computation are usually not reversible at the microscopic level, and this carries over to actual implementations in computers. As a consequence of basic thermodynamics, this irreversibility directly contributes to heat dissipation, and therefore power consumption. However, there is nothing inherently irreversible about computation, and using reversible computation models could therefore lead to lowered power consumption. In the new MicroPower project, the Department of Computer Science at the University of Copenhagen is collaborating with the University of Ghent and the hearing-aid company Oticon, to advance the theory and practice of reversible computing at the language, logic and circuit level.