Home Solar

Clocker

Storage? I am Storage!
Joined
Jan 14, 2002
Messages
3,552
Location
USA
Howdy Doug. How long have you had it installed? Have you been able to estimate if you are on-track for at 5 year ROI? I know it will be hard to determine what winter will bring but just wondering what your overall impression is. If you don't have batteries, is the AC fed directly to your home to just help reduce the amount you are putting from the electric company?
 

Handruin

Administrator
Joined
Jan 13, 2002
Messages
13,280
Location
USA
Hey Kevin! I've had my solar panels turned on since mid day Thursday 9/5/2019 and only had the monitoring working for the past 3 days so I barely have enough data to make any kind of conclusions yet. In the past 7 days which includes a bunch of overcast/cloudy/rainy days due to Dorian blow-over, I'm at a total production of 248.49 kWh based on what my inverter has tracked. I should have a better guess at the end of October/November...but we are also nearing the end of peak sunlight in New England as the sun dips lower in the horizon. Unfortunately it took too long to get my setup online to make the most of the summer. I don't expect much production in Dec > March but only time will tell. The delays were mostly waiting for my town's electrical inspector.

I do not have a battery system so the inverter is tied right into the main lines that come into my house at the meter socket. When I'm generating surplus power, it gets pushed back to the grid and likely goes to my surrounding neighbors, so it's not wasted. I have two new electric meters as part of implementing solar and now when I generate surplus (which I should be based on my plan), my meter runs backwards and I get credits from the electric supplier at the same rate I would pay for power. The hope is that during the peak months I generate enough excess credits to use those credits during the off-peak months. My utility company will never pay me for the credits but I can transfer any excess to people in my grid which is most of the east coast of Mass.

In addition to the credits I will get from my energy supplier, my second meter is a Massachusetts-based SMART program. This meter simply tracks all generated electricity from my panels. I get a separate payment of $0.14 per kWh regardless if I use it or send it to the grid. I get paid during this program for 10 years and they will send me a check every quarter as payment for the power generated.
 

LunarMist

I can't believe I'm a
Joined
Feb 1, 2003
Messages
15,268
Location
USA
I hope it works out for you, but every time I go to NH or MA it seems there is not much sun. :(
I assume you need more panels than the houses in SoCal.
 

DrunkenBastard

Storage is cool
Joined
Jan 21, 2002
Messages
714
Location
on the floor
Looking good Doug. The 14 cents per kWh generated program is a nice bonus.

How many panels again (sorry if I missed that post). All on your southern facing roof?
 

Handruin

Administrator
Joined
Jan 13, 2002
Messages
13,280
Location
USA
I ended up installing 28 panels. These are the parts I had installed:

Modules: (28) LG370Q1C-A5
Inverter: (1) SolarEdge SE10000H-US & (28) SolarEdge P370 Optimizers
Inverter Warranty: Extended to 25 Years
Racking: IronRidge XR100 Rails & IronRidge FlashFoot2 Mounts
Monitoring: SolarEdge PV Monitoring
 

Chewy509

Wotty wot wot.
Joined
Nov 8, 2006
Messages
3,143
Location
Gold Coast Hinterland, Australia
I personally was aware of the issue, and may be more of an issuer sooner-than-latter as many cheaper manufactured panels are on the market that don't have the same life as higher-quality panels. (eg need to replace every 5-7 years, rather than every 15-20 years).

Also reminds me of the study that the H2 Hummer was more environmentally friendly than the Toyota Prius, when you take into account the environment impact of construction, running and disposal/recycling... (unfortunately most people only care about the running phase of the life of a vehicle/appliance).
 

jtr1962

Storage? I am Storage!
Joined
Jan 25, 2002
Messages
3,894
Location
Flushing, New York
The market won't support solar panels with a life of only 5 to 7 years. Half the cost of solar is the installation. If you have to put in new panels every 5 to 7 years the economics don't work out.

While the problems mentioned exist, they can be mitigated designing panels with longer life. We should aim for 50 to 100 years at least, not 15 to 20.
 

Chewy509

Wotty wot wot.
Joined
Nov 8, 2006
Messages
3,143
Location
Gold Coast Hinterland, Australia
The market won't support solar panels with a life of only 5 to 7 years.
I agree 100%. I don't know what it's like in the US, but most companies here use what some may consider misleading warranty statements.

Most here will advertise a 25yr performance warranty (that is the panel will only lose up to 20% of maximum performance rating over 25yrs), however the panel itself only has a 5yr product warranty, coupled with a 5yr warranty on the Inverter. The 25yr warranty being in massive bold print the marketing material, the latter 5yr panel warranty buried deep in the fine print of the installation contract.

And as we're all aware, if the panel only needs to last 5yrs (for warranty), manufacturers will only ensure the panel will last that time and a tiny bit longer... And then they get another sale in 6-7 yrs time...

IMHO modern company policy is to generate continued sales on a regular basis, and products are built to warranty, not for quality... Case in point, look at most white goods, (eg fridges, freezers, etc). My parents had their first fridge for 30 years, (only a regas and new seals at the 20yr mark), their second fridge lasted 10yrs, and according to most reviews you'll should only expect 5yrs on a modern appliance. (I hate to think what the life of these new smart-appliances is going to be, eg new fridge with built-in tablet on the door, etc).

Notes:
https://www.solarquotes.com.au/blog/your-solar-panel-warranty-what-you-need-to-know/
 

Handruin

Administrator
Joined
Jan 13, 2002
Messages
13,280
Location
USA
The article makes sense and I realize that panels have trade offs for environmental factors with regards to their potentially toxic parts. What is unclear to me is if they are properly recycled, what amount of cost is involved both financially and environmentally. Since those aren't as easy to calculate I wonder over the lifespan of say 25 years, that each panel can offset the associated amount of impact from consuming power from my local power plant.

I know this isn't true for all panel types but the LG panels I purchase do offer a warranty for 25 years for material and workmanship as well as a 25 year warrant for power generation performance over the 25 years. Their material and workmanship warranty also covers the labor costs and power optimizer modules. The power generation warranty would be rather hard to prove so I'm mostly interested in the 25 year material and workmanship warranty. I've read in various forums, etc that some complain LG panels are more costly when compared to others but the overall project cost was on par for my area.

I also got my company to include a 25 year warranty on my SolarEdge inverter so that it is covered when it dies around year 12 (which is common). The company that did my install offered a 5 year warranty on their installation part which is a bit low but I was ok with this for the price. Given that they did not route any wiring inside and it's all self-contained right near my meters, my only concern over those 5 years would be leaks in the attic where the rail system was installed.

LG will, at its sole option, repair or replace the Module(s) if it proves to be defective in material or workmanship for a period ending 25 years from the Warranty Start Date under normal application, installation, use and service conditions

...the actual power output of the module will be no less than 98% of the labeled power output. From the second year, the warranty for power output will decline annually by 0.4% in each of the remaining 24 years, so that during the 25th year, an actual output of at least 88.4% of the nameplate power output specified on the Module will be achieved.
 

Handruin

Administrator
Joined
Jan 13, 2002
Messages
13,280
Location
USA
Since my setup has been turned on around 9/5/2019, my inverter reports I've generated 1.4MWh in about 45 days. We had a very long storm come through in the week of 10/9 causing some low generation days but that's expected to happen. The downward trend is due to the seasonal change with the sun dipping lower in the horizon. I won't see it rebound until some time in late December.


pv_output.jpg
 

Handruin

Administrator
Joined
Jan 13, 2002
Messages
13,280
Location
USA
I've just passed the 1-year mark for my solar panels being online and wanted to share where things are at.

Numbers:
Grid electrical cost: $0.24/kWh
Generation payment: $0.1276/kWh
My average cost for electricity accounts for all fees, delivery, etc.
The generation payment is based on Massachusetts SMART program which is in effect for 10 years and only based on production, not consumption.


Over the past 12 months, my solar panels generated 11.04MW/h (11040/kWh) of electricity. Based on the numbers above, that nets me the equivalent of (0.24 + 0.1276) * 11040 = $4058. My electrical meter is measured as as net-metering. This assumes that any electricity that hasn't been consumed is retained in the form of a credit from my electrical supplier at the same rate and applied to other months where I use more than I generate.

My break even estimate right now is about 5.1 years for the system which is lower than I originally estimated of 6.1 years.
$21,000.00/$4058 = 5.1 years to break even.

Usage numbers...note that I only have a partial year in 2019 since I had just moved in on 3/5/2019. So from 3/5/2019 > 9/17/2019 there was basically no solar power for reference.

Read DateUsage
(kWh)
Number of DaysUsage Per DayCost Per DayTotal ChargeAverage Temp(°F)
08/18/20206173219.28$4.32$138.1176
07/17/20203462911.93$2.89$83.8572
06/18/20200300$0.23$7.0065
05/19/20200320$0.22$7.0049
04/17/20200290$0.24$7.0043
03/19/202093293.21$0.99$28.7740
02/19/20204852916.72$4.16$120.5533
01/21/20207083520.23$4.80$167.8633
12/17/20196082722.52$5.14$138.8235
11/20/20193832913.21$3.10$90.0442
10/22/201950351.43$0.51$17.8356
09/17/20196811740.06$9.08$154.3962
08/19/201915983249.94$11.04$353.3873
07/18/201915203050.67$11.75$352.5673
06/18/20199323229.13$7.30$233.7063
05/17/20196832824.39$6.18$173.1252
04/19/20197733025.77$6.50$195.0245
03/20/20193381621.13$5.37$85.9532

Generation numbers reported from my inverter:
1599321149746.png
 

jtr1962

Storage? I am Storage!
Joined
Jan 25, 2002
Messages
3,894
Location
Flushing, New York
So you got 11040 kW-hrs out of a 10.36 kW system over a year? Sounds about right. Most of the estimates give about 1000 kW-hr per installed kW in the northeast. At my current electrical usage I would need a 6 kW system to cover it, although I might prefer something like 8 kW just in case I need to start using the A/Cs more in the summer.

I'll probably move on installing a system once the pandemic is over. Might be a great time since we'll likely be at least in a deep recession, possibly a depression. I should be able to get panels for somewhat less. If I decide to have it installed, that should cost less as well. I'll need a company which can use my tax credits directly and just take that off the purchase price since the tax credits will be almost worthless to us (I have no tax liability at this point, and my mom only has about $1,000 a year federal tax liability). Too bad the solar credits aren't refundable.
 
Top