How long are your panels expected to last, and how much maintenance do they require? Is the 5 year break even point pretty much guaranteed, and considering those things?
They've got 20yr warranties, and require zero maintenance where I live. If you have more rain/snow than I get, or perhaps salt spray etc, you may need to do some cleaning.
Once every few months the monitoring doohickey needs a reboot, but the panels work with or without that.
For my personal situation, unless PG&E reduces their power rates over the next 5 years, I'll absolutely hit that break-even point.
Panel production will degrade over time - the warranty covers something like 3% the first year, and 1% every year after that. So at 5 years I will have less than an 8% reduction in output from the panels. That 8% will be made up by that time with LED bulbs, a variable speed pool pump, etc. Heck, right now out of the ~30 ceiling cans in my house, only my office (4) and front porch (3) are LED. The rest are full 60W sucking incandescent bulbs. The chandeliers are also 60W bulbs too, accounting for another dozen or so lights that are on quite frequently.
What can I say - my wife hates CFLs and barely tolerates LEDs.
You mentioned the reduction in your energy bill, but do you happen to track how much of that comes from selling back to the grid and how much comes from you using your solar power directly? If you're generating 10kW a few hours each day, I would guess that's the only time you're selling back. Would there be any point in an energy storage system for you? I've always had this fanciful notion of having a solar array and building an underground flywheel for storage, but only because I'm riveted by flywheels.
I haven't looked into the ROI of CFLs or LEDs vs. incandescents in a while. I imagine they have improved. Lately, I've even seen some LED bulbs in stores that don't look horrible. Of course, I would buy them anyway just to save time changing bulbs!
I have a similar system, and I sell back for about 80% of daylight hours. That credit covers all of my other needs in the summer (and then some), and about half of my usage during the winter months. When you originally design the system, you use current rates and policies to create a system that generates at most a net zero usage.
I swapped all of the incandescent bulbs that run for more than ~ 15min/day out in our house for some 80+ CRI "warm white" LEDs I got off Amazon. My wife didn't even know I'd changed them till I told her. I noticed the difference for the first day or so, but I got used to it really quickly. I wouldn't hesitate to do it again, and any bulb that fails in my house will be getting replaced with an LED from now on.
Maybe you could slowly transition... replace one bulb a week over the span of a year and she may not even notice :)
Once every few months the monitoring doohickey needs a reboot, but the panels work with or without that.
For my personal situation, unless PG&E reduces their power rates over the next 5 years, I'll absolutely hit that break-even point.
Panel production will degrade over time - the warranty covers something like 3% the first year, and 1% every year after that. So at 5 years I will have less than an 8% reduction in output from the panels. That 8% will be made up by that time with LED bulbs, a variable speed pool pump, etc. Heck, right now out of the ~30 ceiling cans in my house, only my office (4) and front porch (3) are LED. The rest are full 60W sucking incandescent bulbs. The chandeliers are also 60W bulbs too, accounting for another dozen or so lights that are on quite frequently.
What can I say - my wife hates CFLs and barely tolerates LEDs.