Why only 50 watts?
We debated a bit on that question.
The goal was to help us get through the 2 months (Mid-November to mid-January) when we felt we were in need
of more electricity but not so much electricity to create new needs. (Ah human needs)
Having such long distance 700 meters (allmost 1000 feet) total to cover, bigger loads (more then 50 watts each) would of meant bigger wire.
We did burry slightly oversized wire so futur houses can connect. But buying smaller was really softer on the budget.
If you go a lot bigger, it doesn't make sense to use bateries anymore, might as well do a grid-tie system or just have full utility.
Our situation is specific in that we have much of our electricity needs that are catered at the workshop that has full utility with laundry, freezers, tools, etc
For someone who needs/wants to have those services at home, I'd sugest he'd go for more than 50 watts.
But that depends so much on location and specific needs.
We are happy with our small systems, even more so now.
Most of us have cold storage inside house that works naturally for free from october to early june,
rest the time plenty of pv power for fridge
All of us have less then 1kw PV's,
Battery bank of give or take 500ah in 12v or equivalent in 24v
All led lighting, phone, music in 12 or 24v
Inverters that are only turned on when needed
Systems that would cost today between 1500$ to 5000$CAN
depending on exact size and quality.
One thing certain is a setup with trickle charge from grid, makes that you don't
have to oversize your system for those 2 brutal months, thats a money saver!
Allso, when you built a house, money is often short.
With a setup like ours, you could buy battery bank and inverter then buy solar PV'S and regulator later.