After many months of research and browsing on this forum and others, creating pricing average Pivot Tables from the CSI database based on last 6 months per watt pricing for modules/inverters, modeling using PVWatts and then SAM (great suggestion per a JPM post), just snagged a Sunpower 5.44kw system/17 panels with Solaredge @ $3.15/W ($17.1k) in N Cali from a large Sunpower dealer. I declined the additional $500 for Solaredge 25 warranty upgrade. I was able to just get in the last of the E19 320W line which are still very good quality panels. My goal was to get within 5% of $3.00/W which is where I've seen most LG quotes. If I couldn't get there, I'd just go LG. This is the cheapest price by far I have seen with the E19s on the CSI database and only a handful of E20-327 installations beat it recently. Neon Rs were $3.50-$3.60/watt, Neon 2's right around $3/watt, SP E20 327 AC panels $3.50/watt, and higher end X21s were $3.80-$4.25/watt. I used my same principle for buying cell phones as I do here... right before the newest model comes up, the slightly older but still excellent model is a bit discounted before being removed from retailers line list (bought Galaxy S7 right before S8 arrived).
Reviewed Hanwha, LG R/Neon 2 quotes as well as multiple different types of Sunpower quotes. So many installers pushing AC panels and didn't want microinverters. I am aware of risk of the Solaredge ecoystem and future replacements may be difficult but microinverters are a bit more complex and directly under the brutal heat of the roof. Couldn't go lesser efficiency as my sloped roof is all broken up and I have a lovely 40foot cedar shading a tiny portion of this a well which 1) I didn't have the heart to cut down as I love trees and 2) It's slightly on my neighbor's property line.
I just installed a new HVAC heat pump with 7kw heat strip backup (backup turned off for now) as the older one was 25yrs young. Also have an EV that I commute 65 mi 5 days a week (18,300 miles/yr @ ~3.7mi/kwh = ~5,000 kwh) which is ~$650/yr charging off-peak exclusively. Modeling my heat pump and EV (since I've had each less than 6 months), total household use is 13,500kwh annually and about 7000kwh is off peak night time use @ 12c/kwh. General average rate on PGE EV-A rate plan is 0.19c/kwh (been on TOU plan since Nov). With the solar array showing roughly LCOE 8-9c/kwh (perfect world) to 16-18 c/kwh (worst possible parameters used), it made no financial sense to chase after the off-peak usage at a "price/kwh delta" of +/- 2-4 cents vs the modeled LCOE so I modeled mostly after daytime use which had a larger delta and then slightly sized up since wife is pregnant and will run HVAC 24/7 in the coming years being at home with kids all day as well as knowing PGE will continue to shift peak TOU later and later into day (eventually will be selling bulk of production at semi-peak rates and buying from PGE at peak rates which sucks). 5.44 kw array will produce roughly 1.5kwh/W AC (~8000kwh) which I know isn't perfect but bulk of panels face 294 azimuth with just 6 of the 17 panels able to face due south.
My most useful thing I tinkered with was the SAM program by far. I input nearly all of my per hour green button usage to more accurately estimate bills/savings which were a bit off most installers' estimates fyi. I downloaded the entire EV-A rate plan to the program as well. Very interesting and useful. Sadly I only have 32bit computer so couldn't do exact panel/microinverter inventory item analysis (program only does fancy analysis with 64bit) but I did slightly simpler analysis with PVWatts subset in SAM and worked just fine and tinkered with system losses to 10-15% with worst case scenario of slight shading. Overall, this should offset roughly 60% of my kwh usage and slightly more than 100% of my peak/semi-peak kwh usage (in order to model for pregnant wife future kids usage at home) while cutting my bill by 2/3 annually to around $900 ($2,000 savings per year) and ~5.5-6yr payback period. I was able to calculate an Internal Rate of Return of 17% which isn't too shabby.
Thanks again all, particularly JPM, ButchDeal, solarix for their insightful posts about sizing appropriately (not 100%) and if/when higher efficiency panels may be useful.
Reviewed Hanwha, LG R/Neon 2 quotes as well as multiple different types of Sunpower quotes. So many installers pushing AC panels and didn't want microinverters. I am aware of risk of the Solaredge ecoystem and future replacements may be difficult but microinverters are a bit more complex and directly under the brutal heat of the roof. Couldn't go lesser efficiency as my sloped roof is all broken up and I have a lovely 40foot cedar shading a tiny portion of this a well which 1) I didn't have the heart to cut down as I love trees and 2) It's slightly on my neighbor's property line.
I just installed a new HVAC heat pump with 7kw heat strip backup (backup turned off for now) as the older one was 25yrs young. Also have an EV that I commute 65 mi 5 days a week (18,300 miles/yr @ ~3.7mi/kwh = ~5,000 kwh) which is ~$650/yr charging off-peak exclusively. Modeling my heat pump and EV (since I've had each less than 6 months), total household use is 13,500kwh annually and about 7000kwh is off peak night time use @ 12c/kwh. General average rate on PGE EV-A rate plan is 0.19c/kwh (been on TOU plan since Nov). With the solar array showing roughly LCOE 8-9c/kwh (perfect world) to 16-18 c/kwh (worst possible parameters used), it made no financial sense to chase after the off-peak usage at a "price/kwh delta" of +/- 2-4 cents vs the modeled LCOE so I modeled mostly after daytime use which had a larger delta and then slightly sized up since wife is pregnant and will run HVAC 24/7 in the coming years being at home with kids all day as well as knowing PGE will continue to shift peak TOU later and later into day (eventually will be selling bulk of production at semi-peak rates and buying from PGE at peak rates which sucks). 5.44 kw array will produce roughly 1.5kwh/W AC (~8000kwh) which I know isn't perfect but bulk of panels face 294 azimuth with just 6 of the 17 panels able to face due south.
My most useful thing I tinkered with was the SAM program by far. I input nearly all of my per hour green button usage to more accurately estimate bills/savings which were a bit off most installers' estimates fyi. I downloaded the entire EV-A rate plan to the program as well. Very interesting and useful. Sadly I only have 32bit computer so couldn't do exact panel/microinverter inventory item analysis (program only does fancy analysis with 64bit) but I did slightly simpler analysis with PVWatts subset in SAM and worked just fine and tinkered with system losses to 10-15% with worst case scenario of slight shading. Overall, this should offset roughly 60% of my kwh usage and slightly more than 100% of my peak/semi-peak kwh usage (in order to model for pregnant wife future kids usage at home) while cutting my bill by 2/3 annually to around $900 ($2,000 savings per year) and ~5.5-6yr payback period. I was able to calculate an Internal Rate of Return of 17% which isn't too shabby.
Thanks again all, particularly JPM, ButchDeal, solarix for their insightful posts about sizing appropriately (not 100%) and if/when higher efficiency panels may be useful.
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