Solar panel ratings are trash. It's worse than MPG ratings for cars. Depending on the mount angle, time of day, temp, time of year, cloud cover, and dust on the panels, your power will be much lower. Then you have to account for loss from the charge controller, inverter, wiring, and batteries. If you get more than 50% of the rated panel watts in actual usable power after all that, you've done good. That's why people like to direct wire panels to DC loads, but that will only work in the daytime.