I purposely bought a 12v powered incubator because I have a solar generator power box that holds 27 Amp hours of power and I can charge it with 200w of solar. Not sure how long that will run it but it's an option that I wanted after going 2 weeks without power after hurricane Ian!
		
		
	 
It's easy to figure out if you do a little math. People talk about chicken math. I'm an electrician. So I use this math often. LOL
12Volts x 27Amps = 324 Watts
Depending on how many watts your incubator uses, will depend on how many hours it will run on a full charge.
That being said. The average usable sunlight per day, to operate a solar panel, is about 5hrs per day on average. So back to some math...
200Watts x 5hrs of sun = 1,000Watts MAX on average of power produced per day, per 200w solar panel.
 
To find out how many watts you can use per hour, you guessed it. More math! LOL
1,000Watts ÷ 24hrs (the amount of hours you need to run your incubator) = 41.67Watts
41.67Watts is the MAX your incubator can draw in order for it to be sustainable on 1x 200w solar panel. Plus, you'd also need more batteries to store that much power. 
1,000Watts ÷ 12Volts = 83.33Amps
You would need 83.33Amp Hours worth of batteries, to store the amount of power 1x 200Watt can produce in 1 day. 
Bottom line... 
It'll get you through for an hour or 2. But if you want it to be sustainable, you'd need to add a lot more solar panels, and a lot more batteries.