I just bought one of the 1000 watt inverter type generators. I don't think it will get here this week though.
as for how much load a generator can use...
charging batteries... about 8 volts @ 5amps = 40 Watts
Soldering Iron... about 15 to 100 Watts... typically 40W for R/C
electric fan? depends... I'd say about 50w
So I'm guessing a 1000W generator can supply plenty of power for more than a couple of racers