I have 30 panels on my roof with single inverter. It’s basically a 7.5 kW system we installed in 2012. Haven’t had any issues with it so far. I would say that I am probably not the best for comparisions because I have pretty good roof facing direction. It’s basically due south (@39 deg N), plus I live at 8000 feet, so I don’t have any obstructions and with climate, I don’t need air conditioning. In my situation, I try to push all my consumption into the day time as we over produce from 9 am to 5 pm. It’s been a challenge as both my wife and I work during day. Now in the winter, we get tons of snow, so each snow usually kills production for 1 to 2 days as I don’t like getting on the roof to remove the snow form panels…I am looking forward to see how this compares to what we’ve been able to do this summer. It might prompt me to get on the roof…
@todd.mikulenka It appears that your roof and deck are VERY similar to my lay out. I don’t have solar yet, but I was planning on buying a Soft Rake with extension handle. This foam rake stays very pliable in frigid weather. Car dealerships use these on vehicle windows and they CAREFULLY use them on painted surfaces, too.
Any light frost, snow, ice left behind eventually disappears under sunlight.
My worse-case peek hours is 2.78 per day in Dec.
7.5kW x 2.78H x $0.1325 = $2.76 in that day during worse-case peek hours (for me, if it’s sunny)
Clearing snow will be exciting as you’ll be standing almost under the array.
I can give 2 examples:
my dads system: installed approx 2012 (all facing due west, some shading, 5:12 roof or 22 degree angle)
(32) Canadian Solar Poly Crystal 250W panels
(32) Enphase 215W Micro-Inverters (even though these were sized too small for the panels, this was a common practice in the industry 6yrs ago… we didn’t realize the truth until Feb 2018 when I was doing research for my own system and dug into the reason why my dads system has never been above 6kW for a system that’s 8kW on paper)
Problems: EnPhase Gateway (monitor system), died in year 3… found out that gateway only had 2yr warranty… $800 replacement… unit not built to withstand high temps and was originally installed in attic… since moved to inside home for better life expectancy… 1 panel failed in year 4~5… panel glass gasket failed and let moisture destroy panel cells… we don’t know exactly when it failed, my dad didn’t replace gateway until year 5, so system went unchecked other than visual during cleanings… after moisture was seen during a cleaning, a new gateway was purchased shortly after… the replacement panel was delayed for 6mo because dealer could not locate a matching panel… eventually, the replacement was chosen and doesn’t match the older panels…
my system: installed Oct 2018 (all facing due south, no shading, 4:12 roof or 18 degree angle)
(17) SunPower 360W Mono Crystal Panels
(17) SunPower 360W Micro-Inverters
Problems: none so far
Experience: I have 2 dealers local to me that carry SunPower panels… I wanted that brand for the capacity of the panels and overall efficiency… unlike my dads system, I don’t have the roof area to put that many panels… only have a 1200sqft home, so roof space was a premium… after a chose a dealer with the best deal, I pulled the trigger and had them install… I couldn’t be happier with the result… the installer was great, it looks great and does what it should… I’m about to get my first electric bill since the install and the estimate a few days ago was $0 - even in winter… sounds great to me…
overall, these systems stay within 10% +/- a few of each other… given my dads west-facing, better angle, and some shading - against my south-facing, worse angle, no shading, and better panel output/quality… these systems perform in their own rights… we learned a lot over the course… one of the many reasons for SunPower in my system was the 10yr warranty on the SunPower Supervisor (monitor), and its designed to be outside… SunPower also has a $50 upgrade where they add CTs (like Sense CTs) to the mains and monitor energy use vs solar production… the downfall is it updates every 15min… the plus is that it has a cellular backup connection that reports 1/hr when internet is down or off… all that, plus a 25yr warranty on panels & inverters, expected life of panels is 40yrs… guaranteed to have no more loss than 1-2% yr over yr… overall, I wanted the best for my buck, and I’m satisfied that is exactly what I got…
my dads system, $33k 6yrs ago
my system, $23k Oct 2018
both grid tied systems…
my dads system, he is on Net Metering v1.0 - 1kWh for 1kWh even exchange, and he gets to keep his original tiered rates for 20yrs
my system, I’m on Net Metering v2.0 - this gets more complicated… I get credit for each kWh I put on the grid, no charge if I use those kWhs in the same day… but used a different day, I get charged non-bypass charges… in short, works out to about $0.02/kWh when using credits on a different day than generated… crazy math, but I figure I will have 2, maybe 3 months of small charges <$50… rest of the time, my PV system will cancel it all out…
neither of us have EVs, batteries, or gensets… but I’m planning to get batteries within the next 3-5yrs… I plan to refi my house and get batteries then…
anyway, if this is useful to anyone, enjoy… if questions, feel free to ask…
My home looks something similar to this https://cdn.houseplansservices.com/product/t6gt88qr0r9sjfh003j18rbac0/w800x533.JPG?v=10 when viewed from the south except that the dormer for the great room is wider and higher. I put in a Generac 14 kw generator in 2012 with a whole house automated transfer switch and I added grid-tied solar in January 2018. The solar consists of 26 Trina 280 watt panels. 18 of the panels are on the 45° roof planes and 8 are on the 22° roof planes. SolarEdge optimizers are on each panel with a SolarEdge inverter in the room temperature basement. The house is within a couple of degrees of facing due south. Latitude is about 44°. Shading from the great room dormer (or vaulted ceiling) is significant and tall trees within 75’ of the house shorten daylight hours during the winter. Optimizers should have the benefits of microinverters; the system keeps generating even with partial and uneven shading at various times of day and all works well even if some panels are partially or fully snow covered. The total system rating is 7.28kwh and my generation for the first 11 months is just over 7 mwh. We currently have full net metering so I have seen only a basic service charge of about $15 per month since April. I still have almost 1 mhw of excess generation left to help cover my winter usage and I expect the system to generate about 90% of what I use. I have no batteries and the solar ties in on the grid side of the generator’s transfer switch so the solar will not operate when the grid is down. This separation is necessary because if solar and generator were to be connected and the solar’s generation were to exceed the home’s consumption bad things would happen when solar backfed to the generator. New York is solar friendly so the system cost after all incentives was about $9,300 and annual electricity bill savings should be nearly $700. I lost three full days of solar generation to grid outages this year - all three days were bright sunny days during peak generation season so that’s about 100 kwh of solar generation lost.
With your knowledge, I’m surprised you did not install your system yourself. I installed mine in 2011. I had to have a certified electrician to turn it on, an electrical permit from the county, register with the utility commission, and have the utility company sign off once completed. My system is ground mounted and I even built my on racking system from repurposed C channel from old electrical transfer towers. Today, building your own racking requires a PE engineering stamp for weight and wind loads. So yeah, I represent your username!
Great detail…thanks for posting this info…
Thanks for the info…
If I had what I have now at a younger age, I may have done it myself… But when I was young, as we all do, I just moved between bad decisions…
I have the knowledge, but no body to match… I’m 45, and a disabled veteran… The heart and mind of a true Marine… Service injuries keep me from doing what I really want to do… But at least I have the knowledge to not get screwed by those that I hire… I recently installed a whole house fan in my home, something that should’ve took a couple of hours, took nearly 6hrs… And lots of pains pills after… But I did it…
Thanks for the pat on the back…
Also, as a follow up to charges… My 1st electric bill was $2.34… my second is est <$5… For the dead of winter (with storms), great start… Still happy…
Generating power for a couple of days, still a few inverters not responding:
Following others examples I signed up for PVOutput:
Running two arrays totalling just under 7kW:
At some point I’ll update the photos with real beauty shots
I just installed sense on my meter last week, after PG&E approved the interconnection of my photovoltaic system.
I installed 12 SunPower 72-cell (210-230W) modules with SolarBridge Pantheon P250HV microninverters on the roof of my home in Oakland myself (with a bit of help from friends). In total, my array is 2.7 kW DC.
I decided to make my own site drawings and take it to the building department to get it approved. They were happy to take my money for the permit, even if my drawings lacked the detail that normal installers include.
I used the IronRidge racking system, and worked with a friend to lay out the array, install the mounts, and install the rails. We installed most of the panels in one weekend. Another friend helped me install the remaining panels the following weekend. It took me one more weekend to connect the array to my panel, and then the city building inspector came the following week to approve. PG&E approved my interconnection four days later, and I could turn my array on!
I needed a monitoring system so I got Sense with Solar while I was completing the project, and I installed it at the same time that I turned on my solar array.
In the past week, I have been producing about 12-13 kWh each day, and my house uses 4-6 kWh each day. I am hoping to electrify some of my appliances over the next bit so I can better balance my solar production and electricity demand. I may add more solar panels to my roof if I exceed my solar production with the new electric appliances.
DIY POINTS for you!
Do you have an EV? Would seem like a good excess output eater!
Or put up a sign and offer drive-by sunny-day charging, like a 21stC Lemonade Stand for adults, no?
Seriously though, feels like you are a prime PowerWall candidate. Did you notice Tesla is doing a discount due to the PG&E situation?
I should have made more of a stink that I had installed the panels by myself. Didn’t know there were DIY points on the line. I got the system used from someone doing an upgrade and another someone who never got around to doing their install. I used an online service to create the plans. Submitted my permit, purchased the parts at HomeDepot to wire it all together, sweat thru August on the roof mounting and stringing everything.
I REALLY thought I was gonna have to pull it all down but the city inspector had ZERO issues with my install. I was so concerned after meeting a professional solar installer buying wire himself who told me I had to get a $500 tool that imprints on the ground wire where I spliced the solid core to the stranded run going back to the breaker panel. Perhaps they hold their feet to the fire cause they are more likely to try and cut corners.
I got this photo from him of how my jbox SHOULD look
I have been looking into options to add battery to my system, but I think my original plan is still the best. Use the two electric cars I have to capture all the extra solar over what I use during the day. Didn’t keep me from sending 500 kWh to the grid in the first month the system was live.
Lake Mary FL - 11.7 kW with 36 Panasonic 325s, Enphase IQ7x Micro Inverters. Net metering with Duke Energy as a tier 1 system. Got my PTO on September 26, 2019. My best production day so far is 62.881kWh on Sept 27th.
That big open roof area is the north side of the house…
It certainly does seem that in the “now I have excess solar” ==> EV vs PowerWall equation that EV should come first … if it means deprecating a gas vehicle.
Then there’s …
I suppose in that regard you would start with converting a gas hot water tank to electric (hybrid if possible).
Seeing the way they do it in Switzerland & Germany (and Japan with cogen systems) I think the U.S. has a long way to go. Hopefully there will be some leapfrogging!
[Note: This is the end of 2015!]
Meanwhile there are long distance high-voltage DC grid interconnects that approach 95% efficiency, so there’s also that to consider. Anybody who thinks the “What should I do now with energy?” question is a simple one doesn’t have all the variables.
@ixu Thanks for your comments and the link you shared. Europe is definitely ahead on home energy use. I’m not a huge fan of biofuels, and I would actually prefer a geothermal system that used heat pump techology to heat/cool my house and heat water as well. Something like this is available through Dandelion Energy, but they are limited to the East Coast for now. https://dandelionenergy.com/
I don’t have an EV yet, but I am planning to get one in a few years (Tesla Model Y!).
I currently have gas heating, hot water, oven, and stove in my house, which is 1500 square feet and was built about 100 years ago. I plan to replace the inefficient gas furnace with a heat pump central air conditioning unit. The oven and stove will be replaced by an induction range as well.
For water heating, there are a few of options, and I’m trying to figure it out. The cheapest and easiest would be install a heat pump electric water heater, which my utility would give me a rebate for and could reuse my existing plumbing. I could also install a solar water heating system, but that would be more expensive and complicated. However, solar water heating would leave some solar PV capacity for the other appliances and my future EV.
Cypress, Texas
System Size: 8.37 kw
Inverter Type: APSystem YC600
Grid Type: 240V Single-phase
Module type: POLY
27 Panels
ken2: I’m up here in delightful Deland also contemplating solar. Who did your install and did you put in batteries?
@ejcobb: We go to Deland quite one often, nice place. We used Gulf Electrical Services. They were one of many that responded to my EnergySage request. Highly recommend them.
No batteries yet, that’s probably next with a possible generator.
We have an 11.97kW DC array with 38x REC315NP Modules with a SolarEdge 10kW Inverter. Our setup is a line side tap with a single meter reflashed for net metering. Our Grid supplier is Ameren IL.
Late summer the system avg. about 66.38kWh per day. During the fall the avg is 61.11kWh. The highest number we’ve seen to date was 72.51kWh production in one day and the lowest on a cloudy day was 11.02kWh. Our avg. daily usage is about 28.41kWh. We do have two EVs.
We do plan on getting a couple of LG Chem’s or Powerwalls in a couple of years. But overall happy with the array.
