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SolarCity solar installation

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Any downside to turning the inverter on my system prior to PG&E blessing the system and swapping the meter? Won't burn my house down or anything? And I just flip the breakers on the panel and turn on the inverter, correct?

I got the hint from another post here. No damage, you won't blow up your house or PG&E's infrastructure. Just that the power you back feed (over what you use) will not get credited. Better to get some savings than no savings. FWIW, turn your system on and then go to your PG&E web page and check your usage. Before I had my system on, I could see the usage rise towards mid day. After I turned it on, I could see a small rise, then flat line when solar production exceeded demand, then a small rise into the evening. With the new Net Metering meter, I can see my usage go negative--i.e. I am backfeeding and getting credit from PG&E.

As for power up sequence, I turned my inverters on, then the DC disconnects, then the AC disconnects.
 
I got the hint from another post here. No damage, you won't blow up your house or PG&E's infrastructure. Just that the power you back feed (over what you use) will not get credited. Better to get some savings than no savings. FWIW, turn your system on and then go to your PG&E web page and check your usage. Before I had my system on, I could see the usage rise towards mid day. After I turned it on, I could see a small rise, then flat line when solar production exceeded demand, then a small rise into the evening. With the new Net Metering meter, I can see my usage go negative--i.e. I am backfeeding and getting credit from PG&E.

As for power up sequence, I turned my inverters on, then the DC disconnects, then the AC disconnects.
Can confirm that the house didn't blow up as I've had the system on for a couple of days. PG&E has been notified that it has cleared inspection. Not sure what they'll do if they show up and see the system on.:smile:

Have rescheduled my Tesla charging from midnight, to 12 noon to take advantage of the free KWH's until the new meter is installed. Then back to midnight.
 
if everything is installed properly, I don't think there's any downside to turning things on; after the inspection, you'll be asked to turn things on yourself, so why not get a head start? I think the only issue is that if things aren't installed properly. probably a low chance, but maybe not one you feel like taking?
Keep in mind that depending on your meter, if it spins "backwards" it may actually register as usage instead of credit, so I would recommend against it until you get your net-meter installed.
 
FWIW, I monitored my usage on PG&Es web site to be sure that my backfeed was not charged as usage. The graph of kw per hour during the day went to baseline/zero during the time my PV production exceeded my usage. I never saw any odd blips above the baseline. Only later in the afternoon did I see the usage go above baseline/zero. I did have a 'standard' SmartMeter in place (digital, not old dial spinning analog). Will double check this month's bill, of course. YMMV.
 
Awesome! I see my PGE electricity usage goes down to <5 kwh per day, kind of correlates the new solar power kick in:

PGEusage.jpg


solarcity1stWeek.jpg



I haven't charged my Model S on Mon and Tues. Will be interested to find out how Wed shows up. That was the day I charged the car. PGE seems have a lag of the 2 days data.

Anyone knows whether the net usage (5 kwh) has factored in rate for different hours (peak, off-peak hours) and the electricity from solar going back to the grid? I am on EV schedule now.

Yeah I have a small system. Looks like there is room to add more panels.
 
Anyone knows whether the net usage (5 kwh) has factored in rate for different hours (peak, off-peak hours) and the electricity from solar going back to the grid? I am on EV schedule now.

The net usage is the net usage for all 24 hours combined. It's possible to consume more energy than you generated, but have a negative "bill" for your electricity, if you generated during the day and used at night. Unfortunately for me, my peak usage (just after sunset) is defined as a peak time by PG&E.

I imagine you have the "EV-A" plan from PG&E. If so, there's no longer any notion of rate increases at 200% of baseline or 300% of baseline; all usage at peak time is charged the same.

PG&E lets you download the data in 15 minute increments.
You can look here to see my spreadsheet showing the cost of my power. If you just plug in your numbers instead of mine, I think it should be possible for you to see your rough cost of electricity.
Pretty soon it will be "winter", and I'll need to change the rate plan.
Anyway, it's an independent calculation of how much I owe PG&E, and on the right I also wanted to see when the cost is coming from. Charging my car (1-4 am) costs me around $25 per month, but my air conditioner in July (1-9 pm) is costing me well over $100 per month.

Unfortunately, PG&E has been really lousy at explaining where the electric charges come from. Every month, I get a statement from PG&E telling me how many dollars of electricity I used, but it doesn't tell me how they calculate it. That's why I wrote the complicated spreadsheet above, and learned that I was on plan EV-A when I thought I was going to be on plan E-9.
 
PG&E has 30 days from notification to come out and swap the old meter for a Net Metering one. In my case, about 2 weeks. And they need to be able to disconnect the PV system from their equipment (so they do not get zapped if the PV system is backfeeding to the terminals for the meter), so be sure any disconnects are accessible, labelled and not locked.
 
PG&E has 30 days from notification to come out and swap the old meter for a Net Metering one. In my case, about 2 weeks. And they need to be able to disconnect the PV system from their equipment (so they do not get zapped if the PV system is backfeeding to the terminals for the meter), so be sure any disconnects are accessible, labelled and not locked.

Did they call prior to showing up?
 
Did they call prior to showing up?

What, give you some kind of notice so you/someone can be there??? You are looking for good customer service from PG&E? No, they just showed up. Fortunately my wife was at home (she's also a doc, so our schedules are crazy) and I could tell her where to let the PG&E service tech in to check the equipment, trip the disconnects, and swap the meter. Now I am waiting for the obligatory '1 or 2 billing cycles' to get my rate switched from E1 to EV-A, and apparently, because this involves an EV, the PG&E Building/Engineering department needs to be involved, assess my NEMA 14-50 hookup to be sure I am not damaging the PG&E infrastructure, then maybe make me wait for another inspection. Absurd....
 
Keep in mind that depending on your meter, if it spins "backwards" it may actually register as usage instead of credit, so I would recommend against it until you get your net-meter installed.

Yes be careful as my system worked this way before the meter swap. It could not distinguish between in flow and out flow so my meter went up as I generated. The power company would love this. Nothing unsafe at least with my set up but definitely higher cost. Once they swapped the meter then all worked as expected.
 
This is probably why it cost nothing to install in Germany and still costs a ton here in the US. We want to bring 4 guys out to house and do sequences of designs, etc.

IMO it's a function of their unemployment rate being at 4% and having universal healthcare, the incentive is there to do it as efficiently as possible.

The German unemployment rate for September 2013 is 6.9%.

They can afford very large subsidies for healthcare and solar power because they have a very efficient national defense system.

They have the US taxpayer pay the defense of Germany.
 
What kind of inverters does SCTY use? Are they microinverters? If so, where are they sourced from? When a system is purchased outright, is there a fee to use online monitoring tools?

I have an enphase system, get real time monitoring of each panel. A great benefit is that if a panel loses productivity for any reason, my other 23 stay at maximum production, not true with old school inverters.

enphase.JPG


enphview.JPG
 
What kind of inverters does SCTY use? Are they microinverters? If so, where are they sourced from? When a system is purchased outright, is there a fee to use online monitoring tools?
While every installation is different, I've not heard of any SCTY installs using microinverters. SCTY buys appears to buy large quantities of Chinese panels, and combines them with standard inverters from various manufacturers. For my 12.5 kW install they used 2 inverters with dual MTTP, so while not as reactive as microinverters to shading and failure, it does provide 4 "zones" of tolerance to these types of issues.

Monitoring is free...but it isn't nearly as detailed as your pictures. Just a nice chart of power generated per hour/day/month/week/year.

Not sure it makes sense to purchase outright from SCTY...they don't really want to sell it that way, and they price it accordingly. Prepaying the lease made the most sense for me.

SCTY's goal is to get panels up on roofs where they can reap the tax benefits and credits. They aren't as interested in trying to maximize power production as they are in keeping the costs down, which is probably why they don't use microinverters today.
 
I have an east-west system (no suitable south facing roof in No CA). My SC 16kW system uses Canadian Solar panels (63 of them) with individual SolarEdge modules on each panel to handle shading/panel failure. My understanding is that these add-on modules (which clip to the back of the panel and are in series) allow for 'bypassing' of a bad/shaded/underperforming panel. I have 4 individual SolarEdge inverters, for 4 strings of panels. Each inverter individually reports the entire output to SC. If a string starts to underproduce, SC knows about it, and then they would come out, check that string, and replace the bad panel. They guarantee my system output, as I am just buying power from them, so it is in their best interest to keep the system performing as engineered.
 
The answer re inverters is that here in Arizona (where this specific house is), SC uses Power One inverters (made in AZ).Interim report card, based on my experience with the 11kW system we'll be having installed:1. Sales rep: He gets an "A" for his thoroughness and response to my questions2. Legal team: They get a "D".... based almost exclusively on that the so-called "contract" I just signed...isn't a contract at all! A contract is a document binding two parties to commitments, usually, as putatively in this case, one party to perform services and/or deliver goods, and the other party to pay for them.BUT, as I was at pains to show to my rep, I was put under no such commitment! Fine for me as a customer; not so good for me as a shareholder. Messrs. Rive(s) and Musk: are you reading this?
 
So it is now 10/19/13 and I'm still waiting on PG&E. As I mentioned above I decided to turn the system on on 9/24/13. Was able to see the usage online go to 0kW during the afternoon. Then on Wednesday, I called PG&E to bitch about them not showing up. I was assured that someone would be calling within the next week to put the net-metering meter in. I looked today at the usage graph on PG&E's website and on Thursday it started showing my system going into negative numbers in the afternoon. Nothing else has changed. And the meter has not been changed. I'm speculating that PG&E is prepping the software in anticipation of eminent switchover to new meter. But have still heard nothing. I decided to shut the system down so I don't get scolded by the installer. Assuming one is about to show up. Don't you just love PG&E?

Any chance the switchover is done from home-office?