Can I integrate a 4800W heater into my current garage electrical setup? I seem to need too many circuits
There is one way you could do this without a panel replacement that would be safe - whether or not it would be &quot;to code&quot; I'll leave up to the peanut gallery.  (who I am sure will not like this answer at all)
Tear out your 20A circuit and replace it with a 30A with a 30A receptacle.  Not only replace the plug on the saw - but replace the entire CORD on the saw with a 30A cord and terminate the cord in a &quot;motor controller switch&quot; mounted on the saw that has properly rated overload heaters in it that are sized for the current draw of the motor at 240v  (which is likely to be around 6-7 amps if it's a table saw like I'm thinking)  Then run the regular cord from the motor controller/switch to the motor.
Building codes don't cover internal appliance wiring and of course the moment you modify the saw (by replacing the cord) you are no longer covered by UL or any of the other certifications and you are letting the manufacturer off the hook should the saw burn the place to the ground.  But, it is &quot;safe&quot; (as safe as any saw can be - which isn't much) since the motor controller switch protection is no worse than a breaker (and probably better)  And considering the number of tool manufacturers who have bit the dust over the last 2 decades there's a good chance your saws manufacturer isn't around to sue anyway even if you didn't modify it and it burned the place to the ground.
I have a shop full of older metal woodworking tools made in an era where the prevailing wisdom was something along the lines of &quot;we don't need no steenking ground wires&quot; and were all, in their day &quot;to code&quot; so I tend to take &quot;code&quot; with a bit of suspicion.