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Originally posted by slosig:

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Originally posted by offgrid:

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Originally posted by jimmy123x:

And in addition, the batteries have a short life compared to the system. 5-7 years, generally.

We've been offgrid (solar/wind) for over 15yrs with our original batteries. Batteries are Unigy II AGM.

Ditto, except solar with propane powered backup generator and Rolls 1700 amp hour 2 volt batteries, 24 in series to make a 48V nominal DC bank.

Batteries are still going strong after fifteen years though the monthly top off with distilled water doesn’t always happen. Other than that, the only maintenance has been applying a little noalox with a paint brush to any corrosion showing up on the connections, and maybe two or three times in those fifteen years, blowing the tops of the batteries off with compressed air as the ranch can be rather dusty sometimes.

Probably should investigate wind as the coastal breeze is very consistent, but solar has taken care of things well enough I haven’t bothered to do the research.

That's very impressive. Rolls makes great batteries. I'm not familiar with the 2V batteries. We use either 6 or 12 volt batteries as weight and storage space is a big concern for inverter banks.

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Originally posted by jimmy123x:

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Originally posted by 9mmepiphany:

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Originally posted by jimmy123x:
You fail to account for the fact that there is no way in hell the batteries are going to last anywhere near 25 years long.

What batteries are you referring to?

A Tesla powerwall is a battery.

The OP, who you quoted, isn't getting a Powerwall...why should he include it in his calculations?

Okay, reading the contract and legal docs. Getting ready to hit "buy" - a little nervous. I don't like these large expenditures - uncomfortable. Especially sight unseen. I guess that's the power of brand.

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Originally posted by konata88:
Okay, reading the contract and legal docs. Getting ready to hit "buy" - a little nervous. I don't like these large expenditures - uncomfortable. Especially sight unseen. I guess that's the power of brand.

Did you use my referral code?

https://www.tesla.com/referral/joseph20709

Just did my site walk through this morning.

Two guys showed up with Tesla branded vans. Rigged up safety gear and went up on the roof to inspect. Installed (and removed) 3 safety bolts to hook their fall protection gear to. Pulled (and reinstalled) tiles to check the underlayment. Went into the attic to check rafters and whatnot. Looked at my panels and took measurements for the conduit runs.

So far everything looks good, though my roof is showing its age (21 year old concrete tile). Their engineers are going to review the work and create installation plans, provided that they think the roof will survive install with 10 year leak warranty intact.

No real ability to substitute panels, equipment, or do extra work like installing a whole house transfer switch. Essentially, they run a tightly streamlined installation and don't want to get bogged down doing anything other than putting the panels down according to plan.

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Originally posted by 9mmepiphany:

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Originally posted by jimmy123x:

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Originally posted by 9mmepiphany:

quote:

Originally posted by jimmy123x:
You fail to account for the fact that there is no way in hell the batteries are going to last anywhere near 25 years long.

What batteries are you referring to?

A Tesla powerwall is a battery.

The OP, who you quoted, isn't getting a Powerwall...why should he include it in his calculations?

He mentioned it in post 1, if he gets 10 referrals and additionally mentions the referrals in the post two above this one. When the powerwall battery goes bad, you have to replace it, or take it out of the system (when that happens). Just mentioning it.

Aeteocles - thanks for all the insights here. And the referral offer. I just found out my friend did solar recently as well so I'll probably use his code.... Sorry?

I feel like this is like a restaurant with a prix fixe menu and no substitutions allowed. Which is fine if it's all quality ingredients and a good chef.....

Would be good to hear of progress as you go along. Any gotchas to be aware of. I hear the whole process can be about 4 months from order to power on with much of it waiting for PGE.

How's the solar going? Is it on yet or still pending inspection and power on?

I'm still trying to figure out if I undersized or oversized my system. I think I'm using about 1KW when the AC is one. I think my average is about 25KWh but a hot month during the summer can peak at about 40KWh.

The units and power vs power rate is confusing.

We're getting sidetracked with the roof underlayment. I'm getting 2nd and 3rd bids from roofing contractors for the roofing portion of it. Tesla has been pretty good so far. We communicate via text message mostly, no complaints yet.

In a design review, it seems that I have panels and inverter but no disconnect (inverter can disconnect automatically if grid power loss is detected).

But I don't have a manual, physical disconnect it seems. Is an independent disconnect not required? If disconnect is advised, it it from panel to inverter? Or from inverter to grid side? Both?

I have not been reading all the posts. You already know I am a debbie downer on this stuff.

The original cost of this project will double or triple or more before it is done. I will bet $100 on it, but of course the real end cost will not be revealed

I find it fascinating that on one hand we talk about why it is not financially prudent to pay off a low interest rate mortgage to be free of debt. And on the other we can justify spending a huge outlay of cash for something like solar in the city. The hocus pocus arithmetic, ain't it great.

quote:

Originally posted by old rugged cross:
I have not been reading all the posts. You already know I am a debbie downer on this stuff.

The original cost of this project will double or triple or more before it is done. I will bet $100 on it, but of course the real end cost will not be revealed

I find it fascinating that on one hand we talk about why it is not financially prudent to pay off a low interest rate mortgage to be free of debt. And on the other we can justify spending a huge outlay of cash for something like solar in the city. The hocus pocus arithmetic, ain't it great.

I lease my panels. I started saving money the second the array was switched on. My August kwh bill was $27. It used to be $300. With my lease payment that comes to $127, so I saved $163 in August. Different strokes for different folks. I'm not on the hook for maintenance, the array shields half my roof from weather (hail) as the panels are stronger than my shingles/roof. The array also shields half my roof from the sun (Lower AC bills). And the county cannot increase my property tax due to the panels because I do not own them. kwh costs here have significantly increased also.

I'm fine with people bitching. I'm saving two grand a year.

I wish Tesla would come out with a 20kW system, they cap out at 16kW, which leaves me short of enough produced power to cover the e-bill at 105% (estimated coverage with 20kW)

Net savings if we go 16 is about $100 a month potentially, there are positives and negatives (ba dum dum) about it....

Question is if we want to go whole hog solar trading payments to Duke Energy for payments to Tesla/Whomever solar company. Having a stable power bill amount is a positive.

Wonder if it would be better to sell the house, move, get a smaller home with solar installed, there are developments where you can get a brand new home, with warranty and solar, just bury it in the price of the home.

Right now I'm thinking, new double pain gas filled tinted windows all around, more insulation in the attic, replace a couple of doors with more efficient ones, see if it reduces power use, and then go 16 if it works.

Seems it's just as important to rectify any power consumption problems prior to install in order to reduce use to is maximum.

quote:

Originally posted by HRK:
I wish Tesla would come out with a 20kW system, they cap out at 16kW, which leaves me short of enough produced power to cover the e-bill at 105% (estimated coverage with 20kW)

Net savings if we go 16 is about $100 a month potentially, there are positives and negatives (ba dum dum) about it....

Question is if we want to go whole hog solar trading payments to Duke Energy for payments to Tesla/Whomever solar company. Having a stable power bill amount is a positive.

Wonder if it would be better to sell the house, move, get a smaller home with solar installed, there are developments where you can get a brand new home, with warranty and solar, just bury it in the price of the home.

Right now I'm thinking, new double pain gas filled tinted windows all around, more insulation in the attic, replace a couple of doors with more efficient ones, see if it reduces power use, and then go 16 if it works.

Seems it's just as important to rectify any power consumption problems prior to install in order to reduce use to is maximum.

You don't say where in FL you live, but I live in South Florida and did just that (didn't go solar). My house is CBS with a barrel tile roof built in 1966 single story, 1700 sq foot under air, 2200 sq foot with attached un-air conditioned 2 car garage and laundry room.

Adding attic insulation was BY FAR the best reduction in power use. I went from like R6 to fiberglass blown in to R-30. It dropped my electric bill a solid 20% a month. I did the FPL free home energy survey and they gave me a $300 rebate towards it, and I think I paid $350 out of pocket and had a company blow it in to R-30. My bill dropped immediately 20% every single month and could instantly tell A/C was running much less. This paid for itself in under 4 months. It also made the house a little quieter from airplanes. I live next to the flight path of a regional airport so noise abatement was also a major concern.

I switched all of the lighting to LED, and that dropped the bill maybe 3-5%.

I then did all impact windows and doors and increased the glass thickness to 7/16" over the standard 5/16". This made the home much much quieter, the lawn man can be cutting the yard 20 feet from a window and you only hear it if you're standing within a few feet of the window. Doing this dropped the electric bill 10%, BUT dropped my windstorm insurance $4000 a year and they paid for themselves in 3 years. But you have to do every opening to get the insurance discount, ask your agent what it will drop yours.

I then replaced the perfectly functioning (but not big enough) 2002 central A/C in 2016 with a new one, this then dropped the bill another 5-10% depending on the season.

I'd rather do all of these things to my house, to make it much more comfortable inside (noise, security, etc.) and adds more value than going solar. I keep the house at 74-75F under A/C all day 24/7, or if we have a cold front the heat at 78F, I only open the windows about 3-4 days a year. Do 2-3 loads of laundry per week, cook, etc. My most expensive electric bill in August is $175 and during the winter months my bill is around $70 a month. My monthly average would be $122.04 per year according to FPL. Which is half what it was before I went down this endeavor. But without a doubt, attic insulation was the biggest drop on the bill (20%) and super cheap to do.

Close to the Mouse House, we're at 3K sq foot, bill in the summer can hit $500+, winter $200.

AC is relatively new, 13 seer Puron Bryant 5 ton, all lighting is LED, windows are the original builder grade single pane metal frame.
I have quotes for a few windows and have the company coming out to assess the East side windows.

Insulation is the original builder blown in insulation. Thats on the list of things to do.

Fixing the windows and insulation will allow me to set a new baseline for energy use and not oversize the system

Not sure if Dook Energy gives any rebates, I'll have to check. It's possible that with new windows, insulation improvement, and perhaps a few other things I could get the max power consumption down to where a 16kW system would almost zero it's self and that would be good time to convert to Solar.

My thinking is that at some point energy costs will rise, either from war, political reasons (green) supply disruption, weather issues, etc. They won't stay stable forever. Having my own solar energy grid supply would protect us after retirement from these swings.

quote:

Originally posted by konata88:
In a design review, it seems that I have panels and inverter but no disconnect (inverter can disconnect automatically if grid power loss is detected).

But I don't have a manual, physical disconnect it seems. Is an independent disconnect not required? If disconnect is advised, it it from panel to inverter? Or from inverter to grid side? Both?

Every solar installation I've seen has a giant disconnect switch/lever in it's own box, clearly marked, plus a placard with a diagram indicating where the electrical hazards are, and warnings all over. I'm certain a physical disconnect is required.

quote:

Originally posted by HRK:
Close to the Mouse House, we're at 3K sq foot, bill in the summer can hit $500+, winter $200.

AC is relatively new, 13 seer Puron Bryant 5 ton, all lighting is LED, windows are the original builder grade single pane metal frame.
I have quotes for a few windows and have the company coming out to assess the East side windows.

Insulation is the original builder blown in insulation. Thats on the list of things to do.

Fixing the windows and insulation will allow me to set a new baseline for energy use and not oversize the system

Not sure if Dook Energy gives any rebates, I'll have to check. It's possible that with new windows, insulation improvement, and perhaps a few other things I could get the max power consumption down to where a 16kW system would almost zero it's self and that would be good time to convert to Solar.

My thinking is that at some point energy costs will rise, either from war, political reasons (green) supply disruption, weather issues, etc. They won't stay stable forever. Having my own solar energy grid supply would protect us after retirement from these swings.

Builder grade insulation is going to be R19 or even less usually. Having it blown to R30 or even R40 will make a huge difference and get you most of the way, if not all of the way there I think. Go with fiberglass blown in insulation, not cellulose. On my 7/16" thick impact (non gas filled) East facing windows, you don't feel any heat radiating off of them at all with your finger almost touching it or touching it. so windows do make a difference but not as much on the bill as I thought. Tinting those existing windows might work just as well and be much cheaper.

quote:

Originally posted by Aeteocles:

quote:

Originally posted by konata88:
In a design review, it seems that I have panels and inverter but no disconnect (inverter can disconnect automatically if grid power loss is detected).

But I don't have a manual, physical disconnect it seems. Is an independent disconnect not required? If disconnect is advised, it it from panel to inverter? Or from inverter to grid side? Both?

Every solar installation I've seen has a giant disconnect switch/lever in it's own box, clearly marked, plus a placard with a diagram indicating where the electrical hazards are, and warnings all over. I'm certain a physical disconnect is required.

That's what I thought. But apparently (after talking more), for my install based on my location, I only need: PV to inverter disconnect (built into inverter) and inverter to grid disconnect (just another breaker in the panel outside). I don't need another lock out manual disconnect.....

We have tinted the windows, I didn't see much of a drop in the bill, then again, we might not have had as much of an increase.

From comparison of this years energy use to last years, we're running neck and neck on kwh used per month.

So the only options are to reduce consumption and remain comfortable. I'm not living in an 80 degree home for $50 a month in savings.

Found an energy audit link on Dook Energy page, requested they contact me to do the review. Will see what they suggest...

There is a $400 window rebate, $200 Insulation, $150 duct test.

quote:

Originally posted by old rugged cross:

I find it fascinating that on one hand we talk about why it is not financially prudent to pay off a low interest rate mortgage to be free of debt. And on the other we can justify spending a huge outlay of cash for something like solar in the city. The hocus pocus arithmetic, ain't it great.

It's not hocus pocus. It's just the time value of money. Mortgage rates are at all time lows, barely above the rate of inflation. There are more profitable ways to spend your money than pay down cheap debt.

As as an oversimplification, what would you do with $12k?

At 3.5% interest, $12k pumped into your mortgage will reduce your payment by $54 a month for 30 years, or saving you $7,400 in interest over the life of the loan.

Or, put into a solar system, it will save me $180 a month for 25 years, or $54,000 of utility savings over that period.

There's no hocus pocus. That's the straight up rate of return analysis without compounding returns into other investments.

For the record, I have never been a proponent of paying down your mortgage. I would rather leverage my money to make more money than to just say the roof over my head is paid off. There is nothing more financially secure than actually having money on hand. Even a house that you "own" still needs property taxes paid. If you believe that a house is a safe financial investment, take your money and buy a second house--now you'll have two houses that are appreciating.