The difference in watts and kVA is that kVA is capacity where watts are consumed, but other than that they are essentially the same. An engineer will give you the definition that kVA is apparent power where watts are real power, real power being apparent power times power factor, but that is meaningless to most people.
As far as a master timer, again there is the distance involved. Every time the master clock in Ft. Collins ticks off a second and sends out the radio signal, every “atomic clock” that receives that signal is a little behind that time, the further away, the more it lags.
The problem with timing or synchronization of the power signal is that the transmission grid is a grid. The sources of power are distributed among the grid. It is difficult to get the signal from one power station to sync up with the signal from another power station to sync up all along the portions of the grid that they serve.
I have heard people claim that half the power generated on the grid is lost on the grid. I don’t believe that but I have never seen anyone who made that claim be able to name the source or back it up. The closest I’ve seen is a college professor doing a study on a distribution grid in the midwest claimed that 60% of the current that left the substations on the grids hot lines did not return on the return (neutral) line so his conclusion was that 60% of the power was lost.
This college professor was a professor of environmental studies or something like that, he did not have an electrical engineering degree, and from reading his papers, I’m not sure he even knew how to change a light bulb.
Substations are usually located near industrial sections and business districts so that the power first leave on three phase lines for their use. Three phase circuits return power from each phase on the other two phases, not on the neutral lines. At the end of the three phase lines, the phases split into single phase lines to feed residential lines. That current returns on the neutral lines.
Some current on the residential lines may be lost to ground reactance, but it is not really lost, it returns on the next half cycle. In the end though, Kirchhoff is still valid and no current is actually lost, in spite of last weeks show. “EE is math with a hobby” caller.
Back to my point, I’m sure the transmission grid has some losses, certainly resistive losses, those are unavoidable, but I suspect that some are due to phase shifts. A DC grid would solve the problem of losses due to phase shifts, but I doubt those losses are anywhere near 50%.