I think there are other considerations besides efficiency. This depends
on your method of power generation, and how often you work. Cordless
tools can be useful because you can charge them when you have peak
power available from your source. The same is true for compressed air.
If your home's battery bank is fully charged, you can divert your
energy to building spare power for the shop in your cordless batteries,
and building up compression in your air tank.

I also think that, depending on how you work, the loads may not be so
bad. You most likely don't crank your saws constantly for hours on end.
You use these things in bursts. You may be able schedule your work so
that the extra load from these machines is manageable.