I'm not understanding Tesla's website. I'm going to owe a ton of tax for 2021, so I looked at the Tesla solar panel options. I told them my average electric bill was $220 a month and the site is recommending the $24,000, 16kWH setup. I'm using about 60kWH a day. It seems to me the 16kWH setup is overkill. You guys that have the $12k, 8kWH setup seem to be generating 60kWH a day.

We have net metering, but I have no idea how that translates to what FPL will credit me. We pay about $.12 a kWH, but a lot of the is not just electricity generation. There's per kWH fees for fuel surcharge, storm readiness, etc. that make up that rate.

Paying $24k to save $220 a month makes no sense for me. Paying $12k might make sense.

Yeah, with the price of power what it is here, I can easily defend my solar panel purchase as a financial decision with absolutely no virtue signaling.

quote:

Originally posted by trapper189:
I'm not understanding Tesla's website. I'm going to owe a ton of tax for 2021, so I looked at the Tesla solar panel options. I told them my average electric bill was $220 a month and the site is recommending the $24,000, 16kWH setup. I'm using about 60kWH a day. It seems to me the 16kWH setup is overkill. You guys that have the $12k, 8kWH setup seem to be generating 60kWH a day.

We have net metering, but I have no idea how that translates to what FPL will credit me. We pay about $.12 a kWH, but a lot of the is not just electricity generation. There's per kWH fees for fuel surcharge, storm readiness, etc. that make up that rate.

Paying $24k to save $220 a month makes no sense for me. Paying $12k might make sense.

I just pulled up the online quote system for an 8.16 kWh system. Tesla estimates that an 8.16kWh system will generate between 27 and 39 kWh a day (based on my geographic location). That seems pretty close to what I've seen--most people on various forums report seeing low 40's kWh/day during the Summer.

Interestingly enough, it also appears Tesla has increased their prices (at least here in my area) on their quote system. System cost for 8.16 kWh system is now $19,584 before tax incentives and credits. The price last summer when I locked in my contract was $16,000 before tax incentives and credits.

It seems the Sunshine State isn't so much as the site says 26-35kWh a day for the 8kW setup where I'm at. I don't think I have room for the 16kW setup either.

Ya, when you are paying 3 times what it costs me, I can see how it makes sense for you.

And gas is $4.29 for regular.

Just my humble opinions, YMMV.

Having Tesla solar is like having a Tesla car, no one but Tesla or their contractors is going to work on your system. If you're needs stay within those parameters, then by all means go with Tesla.

Going with a solar system without a battery system for use after the sun goes down is like buying a Chassis cab truck and never putting a bed or anything back there for hauling or towing. You really have missed 50% of the prize.

I have yet to see a situation where one size fits all. Any solar system from any MFGR/Installer should be designed with your use and needs in mind, and then add 20% capacity because you will grow into it. Think of solar like your gun safe or garage, you will fill it up.

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All that being said, if you are considering getting the Tesla powerwall, you'll need to do some math on available output of your panels, minus peak draw from you home, minus charge current for the batteries. I'm not super familiar with LI batters but a quick search shows they have some specific voltage and amperage charging parameters for a given complete charge cycle. If during your peak usage there isn't enough available power for you loads and to charge, which one takes precedence? I don't know how that works with Tesla or LI batteries and their associated BMS (battery management system. Being tied to the grid, you shouldn't have to worry about that as there is always available power from there. But if it will affect your bottom line on net metering or TUS or whatever in some way, you'll want to understand the math for all of that.


Tesla Powerwall 2: 13.5kwh @ around $6000. 100% depth of discharge/5000 cycles. 10yr warranty

16 Rolls Surrette 6v batteries: 41kwh @ $5200. 50% depth of discharge/2500 cycles. 3yr warranty

My lead acids are really not giving me 41kwh because I can only go 50% DOD(20kwh), but I sized my battery bank large enough I am only averaging 14% DOD each night year round or I can go 2 days after a full charge cycle before I hit my cutoff of 60% and the generator kicks in (I can only do the three days also because we will drastically cut/manage our power usage if we know we are not going to get full sun). Additionally by only averaging 14% DOD, the cycles is extended from 2500 to 5000. And even then they will still work, just not at 100% efficiency.

With LI batteries I can't find direct confirmation, but you get x number of cycles and they are more or less done regardless of how far they were discharged each cycle.

I'm still learning a lot about all of this even after two years living on solar alone. If I got something wrong other than the opinion section, please correct me.

quote:

Originally posted by LS1 GTO:
And gas is $4.29 for regular.

I didn't realize there was such a difference in the state. I just filled up a couple of days ago and premium was $3.89 in Sacto.

This message has been edited. Last edited by: 9mmepiphany,

quote:

Originally posted by 9mmepiphany:

quote:

Originally posted by LS1 GTO:
And gas is $4.29 for regular.

I didn't realize there was such a difference in the state. I just filled up a couple of datd ago and premium was $3.89 in Sacto.

Gas prices are 10-30 cents different just from neighboring cities around here. Likely from various local taxes.

Sigh. Solar has been down for a couple of weeks. Looks like another month or so for parts and install.

I've turned up the thermostat settings to try to keep me net positive for the annual true-up even though this is the hottest frickin time of the year.

1 month down in its 1 year life - should I be asking for some compensation? The fix should be fully under warranty but 1 month out of 12 seems much. Although 1 month out of 20 years (assuming no more issues from now) is acceptable.

quote:

Originally posted by konata88:
Sigh. Solar has been down for a couple of weeks. Looks like another month or so for parts and install.

I've turned up the thermostat settings to try to keep me net positive for the annual true-up even though this is the hottest frickin time of the year.

1 month down in its 1 year life - should I be asking for some compensation? The fix should be fully under warranty but 1 month out of 12 seems much. Although 1 month out of 20 years (assuming no more issues from now) is acceptable.

Absolutely you should be compensated.
Buy a car under warranty and it is not able to be driven they sure as hell are providing a loaner or rental.

What is the actual issue?

Not sure. Some part needs to be replaced. Seems like spare parts should be readily available locally.

Not only has Tesla raised the cost, they are now requiring you to buy powerwalls, the reason is they now put the inverter in the Powerwall, which is management speak for "nobody is buying our $8,000 power walls"

What was a full 18kW system (max) at $32K is now required to have 3 powerwalls doubling the cost. Not sure why anyone would want to drop that kind of coin on an asset that will deteriorate and require replacement, god forbid a Li battery cell gets damaged and burns the neighborhood down.

Nonetheless, we were about to buy the Tesla panel system only, but not dropping the now double required cost for something that wasn't going to have a reasonable payback to begin with. Not to mention I don't want battery walls.

The sales pitch was that the new walls have built in wifi to the national weather grid so they know to start supercharging if bad weather is coming, and they protect you from brown outs.

Told him we don't have CA style brownouts here so we don't need the walls to supplement my already installed generator backup in case of bad weather..

I would go with generac before I installed powerwalls. More power, more versatile, much cheaper. And I’m gonna guess more reliable at this point.

I don't remember the last time I had a power outage that lasted more than an hour. Maybe when I was a kid.

I bought a cheap 2000 watt Harbor Freight inverter generator for emergencies, just to alternate between the two fridges if I had to. I had boxed up in my garage for a whole year. Finally opened it up last month, did the recommended engine break in, then did the recommended storage procedure, and now it's back in the shed.

I hit peak generation of 54 kWh/day last week, so that's been good. Overall an excess of 7.5kwh per day, even with some typical AC use.

So far I'm happy, but of course I haven't had any problems. We'll see how that goes.

quote:

Originally posted by konata88:
I would go with generac before I installed powerwalls. More power, more versatile, much cheaper. And I’m gonna guess more reliable at this point.

If you dent it and poke a hole in it with yer Tesla it probably won't go up in flames like a Li battery cell

just went to their website and based on my location, the all up cost was $74,000 - $90,000 with a very generous $1000 solar credit from Arizona

yeah, I'll keep paying $150 per month for power

quote:

Originally posted by nhtagmember:
just went to their website and based on my location, the all up cost was $74,000 - $90,000 with a very generous $1000 solar credit from Arizona

yeah, I'll keep paying $150 per month for power

Break even in, what, 100 years?

I wonder how long it will be before the utilities say - hey, all these powerwalls, I'm just gonna take some of that as power sources for the grid at night. Utilities already make solar somewhat unattractive with the TOU and zero benefit net metering schemes. They'll figure out ways to pinch any additional benefits you expect to derive out of the system. Corrupt bastards.

Not sure why Tesla changed the game, just priced the product out of the market here...

Not sure either. Wild guess - solar system itself was just a commodity - no Tesla IP and just a system installer using a bag of 3rd party parts.

Powerwall has Tesla IP, Tesla parts and healthy margins....

But don't really know.