Inverter no load power depends and varies greatly with the brand.
Cheapie 400W ~$40? A Vector VEC024? That takes about 60ma no load.
I had a flea market no name 300W that took over 2A no load!
Could have been over 3A. Long time ago.
Also remember the efficiency is low, at a low percentage of the maximum watts.
Most cheap MSW inverters have the best efficiency at around 90% of the rated maximum continious load, like a 400W inverter does best at 360W load.
I have reports that the cheap inverters and cheap 120VAC CFLs kind of "argue" with each other. One wins. The other burns out. Flip a coin.
Not sure how right they are, but my luck wasn't that great either. So now I use name brand $20~25 11W 12V CFLs. The 11W makes considerably more light and only uses about 200ma more than the 7W.
A customer is running 12 or 14 name brand 11W 12V CFL in an off-grid dairy barn maybe 4 hours a day. Very humid. Even 2 in the milk house because the inspectors require that. The CFL box says not to do that. I only replaced 1 in maybe 3 years now.
Oh. Not sure how many real hours. The barn switching is set up for every other light, or all the lights. Half the CFLs have less hours than the other half.
You may find a 175W Vector and 10 120VAC 13W lights to be more efficient and $10 cheaper.
Avoid those little 75 to 100W do-hickys without any wires that plug straight into the lighter.
G-