PV solar power does not really work like that. The amount of power coming from the panels is constantly changing with the amount of sunlight that is hitting the active surface. Here is a plot from my Enphase system.
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The Enphase system only plots the total in every 15 minutes, so it looks pretty smooth. At sunrise, the power is very low, as the sun rises, it comes out of shadows and the angle of the light on the panels improves and the power output increases. Peak power in my case happens between noon and 1 pm. And the peak power is typically only 80% of the panel rating. This day hit about 3,600 watts from my 4,800 watts of panels, or only 75%. It does a bit battery closer to summer as the panel tilt becomes closer to the angle of the sun at noon. If there were no obstructions and a clear sky, the fall off would be a mirror to the ramp up, but you can see the dips around 2 pm and 4 pm. Those are due to shadows from trees as the sun is falling to the west.
Here is a different day shown from my Victron DC system.
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The morning ramp up is similar, but on this day, we had some clouds move in. The blue trace is the power from the panels and the orange trace is my battery bank voltage. The MPPT charge controller does it's best to keep pushing as much power as possible into the battery. My DC system has 2,000 watts of panels on it. That energy helps charge the battery on my hybrid backup inverter.
The inverter then pulls power from the battery as it needs it. The two rarely ever match up. This is why the battery is very important. Think of it as a big bucket. The solar panels throw water in as they can, and the inverter keep scooping it out as it needs it. If the battery (bucket) becomes full, the solar no longer has a place to fill and has to start just throwing away the energy (water). On the flip side, if the solar is not making enough, the bucket will run dry and the power has to shut off until it can fill up again.
A grid tied hybrid system has another option. If the battery becomes full, the extra power might be able to be exported to grid and you might be able to get some credit for it. And if the battery runs too low, you can then start taking power from the grid.
It's not so much about how much power the solar panels put out, it is how much total energy they can produce in the day. Can they make enough to keep up with your load demand on the inverter? We use the term "Sun Hours" to try and make it simpler, but it also causes some confusion. My Enphase trace above made 23.8 kilowatt hours from 4.8 KW of solar panels. That is 23.8 / 4.8 = 4.96 Sun Hours hitting the panels. But to do that, the system was making some power from 6:30 am to 5:30 pm, that's 11 hours.
So don't think so much about the power you need. That is important to figure out how big of an inverter you need, but the solar array size is more about the total energy needed over time. A small 100 watt load running for 24 hours is 2,400 watt hours. But a 1,200 watt microwave oven, running for 10 minutes is only 200 watt hours.
You should start out by doing an energy audit to figure out how much total energy you want from the solar panels. Will this be grid tied? Off Grid, or Hybrid? Grid tied is easy, but may not save you much money now. Grid tied just pushes energy into the grid. If you don't use it, it goes out to the grid and you might get some credit for it, if you use more than the panels are making, then you pay for the extra you need from the grid. Pull 3,000 watts while the solar panels are making 2,000 watts, then you are pulling 1,000 watts from the grid. Off Grid is tough as you need to over produce 95% of the time to cover those 5% of days when there is not enough sunlight. Hybrid is a good balance, if the gri is available. My system is now a hybrid. I have a otal of 6,800 watts of solar panels and 36 KWHs of battery. It covers all my electric energy needs for 90% of the days. I am using a little grid power now as we are into a second day of cloudy weather. My Enphase system only made 13 KWHs yesterday, only 2.7 sun hours. Wall down from the 26 KWHs (5.4 sun hours) it made 2 weeks ago.
