  Molecular motors work collectively to transport cargo within cells, with
anywhere from one to several hundred motors towing a single cargo. For a broad
class of collective-transport systems, we use tools from stochastic
thermodynamics to derive a new lower bound for the entropy production rate
which is tighter than the second law. This implies new bounds on the velocity,
efficiency, and precision of general transport systems and a set of analytic
Pareto frontiers for identical motors. In a specific model, we identify
conditions for saturation of these Pareto frontiers.
