Solar is Actually Cheaper

I finally did a deep dive analysis of solar power for my house. I did the same thing maybe 10 years ago and concluded it wasn't economical back then. Now it's actually economical, that is, it's cheaper than grid power with some caveats.

The system I "designed" is a whole house, not connected to the electrical grid system. It's pretty expensive ($30k+) but is probably significantly cheaper over 20 years (the system life) than 20 years of grid power. (We pay about $2,500 per year for electricity.) It's $30,000-ish versus $50,000+ for grid power. One of the big unknowns for me right now is how long do the very expensive batteries last. I would use a number of lithium iron phosphate batteries. A 4.8 kWh battery (a typical american home consumes 30 kWh per day) is about $2000 right now! For 30 kWh it's about $14,000 in batteries (7). If the batteries really only last 5 years that's adds a lot to the system cost and it's not economical. If they really last 10 as the manufacturers claim, it's probably economical.

What does the system look like? It's pretty big. It's a 15 kWatt (more or less) system that uses 320 Watt panels. I'd build 3 arrays of panels that are 11 feet by 17 feet! The overall footprint of the panel arrays would be about 40 feet wide by 10 feet deep. I have plenty of land, but I'd actually have to prepare the area for the array, but I have the tools for that already. I'd build a small shed for the batteries and the controller/inverter. The shed has to be heated, insulated and equipped with a fan by the way. I could put all the batteries and controller in the house, but I'd rather keep it separate.

It's significant that it's cost effective where I live, because I'm in one of the worst areas for solar in the lower 48 states. It's very cloudy here (as cloudy as the Pacific Northwest). Everywhere else in the lower 48 is better for solar, so the system would cost less. In short everyone in the US with some property could produce electricity for significantly less money than a utility company can.