I just don't see the return on investment by charging solar.. the same money spent on solar panels put into batteries would increase runtime more per $ spent.. just recharge when the power comes back on.
Another point is that the incubators are very unlikely to run at 100% duty cycle.. they may run at the same time, so the invertor power rating needs to be able to supply both, but in all likelyhood they run closer to 20-40% duty once up to temp...
So 350W x 2 = 700 W x 35% duty = 210 W average draw.
Lets say you want an 8 hour run time, so 210W x 8 = 1680w.hr
Using a 12V system, 1680/12 = 140 Amp hour minimum
According to
http://www.chem.hawaii.edu/uham/bat.html, batteries amp hour figure is typically given over 20 hours, and it's not a good idea to discharge a whole lot faster than that.. a typical car battery is 50 amp hour, so you need a minimum of 3 to get 140 AH, but that will be discharging them too fast..
Peak draw is 700W or 60amps
typical car battery (50AH over 20 hrs = 2.5A continuous), you need 60/2.5 = 24 batteries to really follow suggested guidelines on amperage draw.. 24 batteries would have 24x50AH = 1200AH, which would mean you could run nearly 60 hours on that bank of batteries..
If you had about 6 batteries and a 1000W inverter and charger, I think you'd reliably have 8 hours, and most likely more run time... Adding solar isn't going to help you if the power outage happens at night, so you need the storage capacity to get you through that.. Additionally, if 210W is the average draw, you're going to need
at least 600W (probably 1200) of solar panels to even get close to keeping up with that, that's if you have reliable sun when you're battling storms.
A gen set is so much easier.. Honda makes some little inverter gen sets that only throttle as much as required to generate the power, they're dead silent and tiny for that power output
Lo and behold
http://powerequipment.honda.ca/generato ... es/eu1000i
7 hours run time at 25% load! and it's only $1k, which is about the price of the batteries alone.