122%! That’s my past 365 days of solar generation (19.5 MWh) as compared to my annual home use (16 MWh in 2016) when I installed my first 40 ACPV ground mount panels (10.4 kW in May 2016). But as someone mentioned, it’s a moving target. If you’re like me, you’ll add EVs and then more panels...
I bought EV #1 (Cadillac ELR) in June 2016 (8k miles per year uses 2 MWh). A few months later, I added EV #2 (Volt using the same 2 MWh of juice as the ELR for similar miles driven). Then EV #3 (MS) in Dec 2016 (used mostly for long trips with free SC). Most utilities - like mine - will limit what they allow you to install. Their grid (you’re connected to), so their rules. Just reality of electric tariffs and utility influence on state utility boards. My REC made me prove I needed more power before I could add phase two (20 additional panels equal to +5.7 kW), which I did a year later (May 2017). I could only do my solar expansion after proving a year worth of increased consumption tied to my EVs.
For those adding solar, think long term and have your panels face SW to West. This produces more PEAK afternoon/early evening kWhs that are far more valuable to the grid and you. Just a few months after my first phase of solar was installed, my Iowa REC changed the rules (their tariff). They moved to Time Of Use (TOU) prices and DOUBLED the price (from 8 to 16 cents per kWh) during their new peak time (4-9pm, 7 days/week). While I get net metering, it’s cashed out monthly (most utilities are annual true-up). The only good news is they pay me 11 cents for my excess PEAK electricity, whereas excess off-peak only pays me 3 cents per kWh.
Also, if you want REAL numbers based on my midwestern solar production, here’s what you may find very useful. My original 10.4 kW solar system produced 12.5 MWh in its first year. On my one year anniversary, I expanded my system to 16.1 kW, and it just produced 19.5 MWh over a year. Yet I installed my final 20 panels at 225 degrees Azimuth (SW facing), and I didn’t lose much, if any, efficiency for not facing the panels straight South (as all installers will say is best). It’s not best, as South panels produce peak energy at Noon, which is off-peak and for my net metering agreement, only 27% (3 vs 11 cents for excess monthly cash out from April through October) of the value.
To hyper-conserve my peak electricity usage (so I could sell back more 11 cent peak excess) I also switched out over 100 old light bulbs to LEDs (only about a buck each at Sams). So that brought my annual home energy demand from 16 down to 14 MWh. Plus another 4 MWh for my EVs is now total annual electric consumption of 18 MWh. So with my solar production in the past year at 19.5 MWh, that now leaves me at 108% of my TOTAL (home plus EVs) usage. Al Gore can have my extra 8% to go toward his private jet’s CO2