Begin at the End (User end)

We know we want to design a system that can deliver 220 VAC at 100 amps.

This has many advantages.

1. No special wiring in the house.  It can all be standard house wiring
2. No special load centers or breakers etc.
3. No special appliances

Ultimately, it will act exactly like regular power from the electrical grid.

The only thing we need to consider is how to feed the solar energy system into the house.

I will probably feed it in like a normal auxiliary power source, like a generator.  This will allow you to switch over to grid power in the future, or even have grid power available in case the solar energy system is down for some reason. 

I would tie the solar energy system into the main panel using a generator interlock kit and a 100 amp infeed breaker (100 amps because that is what we are designing the solar energy system to supply)

The interlock is important for a few reasons.  

1. If you ever tie into the grid, this keeps your solar energy system from backfeeding onto the grid. If you ever tie to the grid, and interlock is required by law.  Failing to use one can kill power line workers.
   
2. It provides a simple path for connecting to the grid if you ever decide to.  All you have to do is hook your main breaker into the grid feed, just like any other installation.  Then, flip a breaker and you are on the grid.  Flip another breaker and you are on solar.
   
3. It keeps the grid from backfeeding into your solar energy system and killing you, or damaging your solar energy system.
4. It's cheap!  It is typically about $100 to add an interlock to your main panel.
5. It's easy!  Just drill a  couple of holes and drive a couple of screws.

To summarize, Everything on the load end of the electrical panel is exactly as you would use in a normal system.  In the load center, you would add a generator interlock and a 100 amp infeed breaker.