  In this paper, we provide non-averaged and transient performance guarantees
for recently developed, tube-based robust economic model predictive control
(MPC) schemes. In particular, we consider both tube-based MPC schemes with and
without terminal conditions. We show that the closed-loop performance obtained
by applying such MPC schemes is approximately optimal when evaluated both on
finite and infinite time horizons. These performance bounds are similar to
those derived previously for nominal economic MPC. The theoretical results are
discussed in a numerical example.
