Expert: Dan - 1/7/2009

Question
I have been looking into generators for the past month, and am torn between inverter and non-inverter generators.  I want to be able to run electronics off the generator, but am put off by the extraordinary cost of the inverter type.  Simply put, with my electronics protected by gfci breakers, outlets and surge protectors, do I really need to spend the extra $ for an inverter generator?

Answer
The best power comes from a plain and simple generator.  This is where commercial power comes from, a rotating magnetic field in a coil that generates a nice pure sine wave.  Not sure why you seem to imply that electronics need something else - this is what they get out of a wall socket, what they are all designed for.  I don't know why you need gfci or surge protectors, a home generator is pretty safe from transients that can come off the power lines from faults, lightning bolts, etc.

The deal with inverter generators (which is a new thing) is that the engine can run variable speed, and there are no brushes.  New powerful Neodymium magnets make this possible, you can make a pretty efficient little alternator pretty small, but you can't control the output voltage, so it is difficult to use the output directly.  So to solve this they make it a 3 phase alternator which makes really good DC power when rectified (so far pretty cheap, too), and then they have to make that DC back into AC, requiring the expensive inverter.  Most cheap inverters suck, because it's really hard to synthesize a good sine wave, so they cheat and make squarish waves.  If you have equipment that can deal with these pseudo-sine waves, that's the way to go as they are very efficient.  Most electronics have no problem with this, as they take the line and make it into DC right away anyway.  Like a compact fluorescent bulb, or a PC.  But some appliances have a problem with this, in particular anything with a power transformer in it, like an older microwave oven or stereo amp or fluorescent tube fixture or ceiling fan.

The disadvantage to a generator are that the line frequency isn't very constant (but no electronics care about this anymore), regulation can be worse (you can pay money and fix this - get a generator with electronic regulation), and engine wear can be higher (the inverter can throttle down with no load, the generator can't)

So I'd go with a regular generator.  Get one with a good engine (a Briggs or Honda or Subaru maybe), and ball bearings in the engine and generator.  I've seen sleeve bearings in plastic that just melt.

-Dan