Yeah - even with PGE trying their best to screw over solar customers in the last few years, I figure we've at least gotten our money back in ~15 years of owning a ~4KW system. Something like 75 MW generated in that time, assuming the inverter is more-or-less correct. At this point, doesn't make any sense anymore, since they only credit you like $0.1 and charge you $0.6 (I haven't looked too closely at it) - you'd have to generate 5-10x your consumption to mostly offset it.
We bought ours in '10 to offset high AC use in the summer - we were paying $1000-1500 a month for 2-4 months in the summer. The first few years, our "year-end" balance was < $1K (we just paid minimum payments the rest of the year), so I figure we easily saved $2-3K/year in those early years, and after the incentives in those days, we paid ~$14K, so maybe 7 years to pay it off. Our year-end balance was more like $3K the last time, and I think we're still producing 80-90% the same power, but PGE keeps changing the plans around. At this point, I'm interested in upgrading our cells from 300W to 450W, but I'd only do that with a battery system that also stores energy so that we could go more or less entirely off-grid. But probably need a new roof first..
We bought ours in '10 to offset high AC use in the summer - we were paying $1000-1500 a month for 2-4 months in the summer. The first few years, our "year-end" balance was < $1K (we just paid minimum payments the rest of the year), so I figure we easily saved $2-3K/year in those early years, and after the incentives in those days, we paid ~$14K, so maybe 7 years to pay it off. Our year-end balance was more like $3K the last time, and I think we're still producing 80-90% the same power, but PGE keeps changing the plans around. At this point, I'm interested in upgrading our cells from 300W to 450W, but I'd only do that with a battery system that also stores energy so that we could go more or less entirely off-grid. But probably need a new roof first..