KUKA does offer energy monitoring on KRC4, but I have never looked into it or used it. My guess was that question was asked since robot is considered for purchase and not yet available. If one has the robot and it is running some program, one can easily hang a clamp meter on one (or all) phases and see current draw - power is easily computed from that even if device does not offer own means to monitor power or energy... On KRC one should also be able to do that just by using Trace tool that is part of the KSS
Now, we are only considering the concept of robotics and calculating the costs. It would be great to get the average and maximum value of the robot consumption for approximate calculations.