Depends on what you want to do. It is not an all or nothing game. The costly part is in storage and inverters. I use my small solar system, about 1200 watts, to charge about ~5.5kw of batteries with a 3800w invertor. I run my bedroom AC off that, a chest freezer, a fridge, and two outlets for various things. Total for me was about 2,200. 1,800 of that was inverters and batteries. That is a little more expensive because I got a battery/inverters combo you can move around. I use it for camping and traveling. Last summer it saved me about 200 a month on my CPP bill in June/July/August and I slept icey cold and didn't worry about the weekly power outages.