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Light Emitting Decoration
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What pv panel/ inverter supplier would you use.
I have no idea. All I am saying is that solar is not self-supporting under ordinary conditions and getting a payback within the useful lifetime requires Government handouts or hand holding and resources to make that happen is tapping out. So, it's all about the political climate.
 

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Table Notes Analysis Calculations
Annual Inflation 1.50% NPV = $360,005.40
Base Annual Electricity Bill $48,823.49 IRR = 11.91%
show me that fund you speak of,

solar pv works because power costs only go up and never down. EVER.

I pay 10 cents per kwh and makes no sense for me but those paying 25 cents seems like a good deal and does pay back - of course with no payday loan percentage.

I made $5000 in one day because Greece acquiesced, but that doesn't happen none too often. To the chagrin of my broker I moved it to my cash account for a previous loss, I also know that by IRS rules I can't buy back in for another 90 days without paying capital gains.

edit, could be more than 90 days but dont care, got 12" of snow o tuesday and covered by 3" of ice friday and the fan hit the plop.
 

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I put solar on my house about six years ago. I did it as an investment that would pay for itself and save me money over time. For me it paid off and was paid for in four years. At the time the federal and state government paid for a third of it.

My cost was $11,000.00 for a 5,000 watt system that only covers half of my electric needs. That price was for the panels, racking and the inverter. The rest of the materials and permits were probably another $500. I installed them myself with two co-workers help.

I had an Excell spread sheet that I made up. I put my meter readings in it once a month. This sheet was loaded with formulas from the cost of electricity to the average temperature and daylight. It had a countdown for the cost, and it took four years. It would have taken less. When Gov. Christi got elected he changed the dynamics. The SREC credits went from $600 a credit to $50. I get six credits a year. They came back to around $150.

To the OP your cost seem excessively high. I would not think it is worth it.
 

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One more Electric Light

What pv panel/ inverter supplier would you use.
The local permitting departments require a set of Prints ,you know what a typical set of prints for solar installation would consist of.

My town also required a drawing with a structural engineer or architect's stamp on it. I tried to do it myself and had drawn it up with weight calculations. They would not accept it. I got a Craig's list architect to review and stamp them for $200.00.

There was quite a few of us putting solar on our houses, and my town was the only one requiring the stamped drawings.

I don't remember the town bothering with electrical drawings. It was a state system they had set up for the incentives and inspections. They reviewed it more than the town.
 

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Discussion Starter #65
cabletie said:
I put solar on my house about six years ago. I did it as an investment that would pay for itself and save me money over time. For me it paid off and was paid for in four years. At the time the federal and state government paid for a third of it. My cost was $11,000.00 for a 5,000 watt system that only covers half of my electric needs. That price was for the panels, racking and the inverter. The rest of the materials and permits were probably another $500. I installed them myself with two co-workers help. I had an Excell spread sheet that I made up. I put my meter readings in it once a month. This sheet was loaded with formulas from the cost of electricity to the average temperature and daylight. It had a countdown for the cost, and it took four years. It would have taken less. When Gov. Christi got elected he changed the dynamics. The SREC credits went from $600 a credit to $50. I get six credits a year. They came back to around $150. To the OP your cost seem excessively high. I would not think it is worth it.
Not every1 can install it themselves, so would you say it's worth it if you had to pay a contractor to install it? Here in CA a 5-7KwPV system runs around 30K installed.
 

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I don't see how it could be worth it if it takes 30 years to pay off. My Sharp solar panels are warrantied for 20 years and the sunny boy inverter is less than that. I thought I remember that the output loses 2% a year. What is left after 30 years?

I also had help with all the paperwork, shading analysis and a good deal on the material through this non profit.

http://www.americansolarpartners.com/index.php
 

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Light Emitting Decoration
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show me that fund you speak of,

solar pv works because power costs only go up and never down. EVER.
What fund? Those figures came from the PDF I linked. Cents per kWh going up isn't really an increase except for the portion beyond inflation rate. Solar PV barely works, because the Government is paying for it or the local power rate is anomaly high.

I pay 10 cents per kwh and makes no sense for me but those paying 25 cents seems like a good deal and does pay back - of course with no payday loan percentage.
10 cents/kWh is closer to the typical value. 25 cent and higher are based on higher tier rate used by SDGE, PG&E and like as a form of excise tax. Solar pushers like this as it makes it look favorable for solar marketing. You still haven't made clear what percent discount rate you use to properly factor in expenses(insurance, maintenance), time value of money and risk (withdrawal of Government funded subsidy and payment going to market rate wholesale rate).

I made $5000 in one day because Greece acquiesced, but that doesn't happen none too often. To the chagrin of my broker I moved it to my cash account for a previous loss, I also know that by IRS rules I can't buy back in for another 90 days without paying capital gains.
Suffice to say you know enough about investments and finance to know you need to use discounted cash flow, but you're kind of dodging the topic of time value of money when we talk about solar payback.

Why don't solar installers let you pay the cash price over 9.4 years in payments instead of lump sump? 113 payments of $100 is $11,300 by their own logic :thumbup:

I put solar on my house about six years ago. I did it as an investment that would pay for itself and save me money over time. For me it paid off and was paid for in four years. At the time the federal and state government paid for a third of it.

My cost was $11,000.00 for a 5,000 watt system that only covers half of my electric needs. That price was for the panels, racking and the inverter. The rest of the materials and permits were probably another $500. I installed them myself with two co-workers help.
To save money over time, the savings must exceed the opportunity cost.
Someone with debt requires a higher payback rate to save money. You have debt (car payments, credit cards, student loan), a lump sump payment of $11,000 would shed some interest expenses.

Grossly simplified to show concept:
If you would've saved $1,500 in interest expenses by paying a $11,000 lump sump payment, but you bought a solar system instead that saves $1,000 after breaking even in the same time frame,you lost $500.


I don't see how it could be worth it if it takes 30 years to pay off. My Sharp solar panels are warrantied for 20 years and the sunny boy inverter is less than that. I thought I remember that the output loses 2% a year. What is left after 30 years?
A payback period that long is generally reserved for Governments. You're asking very good questions and staying i touch with the reality. :)

I believe the reason for so much variation in the rate used for "discounted cash flow" is that there are different ways of viewing risk. A certain percentage of them will fail outside of warranty, degrade and become damaged due to accidents, acts of God, etc. So, insurance premium would have to be deducted from the savings and issues not covered under the policy would have to be factored into choosing the discount rate needed.

The ROI calculations used for solar sales to homeowners ignore those.
 

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http://www.dailyfinance.com/2014/06/11/is-your-credit-card-debt-average/

Credit cards are usually in double digit APR and the average American has a four figure credit card debt.

Solar purchase should be avoided unless you owe absolutely zero on credit cards. Solar gives you no utility value (the only value is bill offset), so paying off credit cards will always have a better ROI.

Solar sales, payday loan lenders, etc are fully aware of time value of money and they both know that cash flow is gold. If the commission and markup can be fully deferred for the full payback period for zero interest, they wouldn't show interest in selling solar.

Payday advance seeks large interest for large mark up for immediate cash.

Energy sales companies simply assign themselves zero interest payday loan in essence, because solar panels have no utility other than reducing the billable kWh and do not provide useful functions. So, the purchase of solar system gives energy sales people a cash advance for which the installed product pays back the lender very little at a time for a very long time.

Sales people setup presentations to convince people believe something is a good deal and mocks your money as something that's sitting around in the corner unused but all he wants is to be able to walk out with it now and today.

Most people value cash flow and liquidity. Solar is a great way to lock away money that you likely need soon and force you to borrow it, because you can't unlock the locked money. So, if you're someone who can see $10,000 to $30,000 the same way an average American sees as a quarter in his pocket, solar could possibly potentially work out.
 

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Here would be the question had it been from my area with the required information:

How long would a $20,000 PV system take to payback that has a total size of 7,000 kWh and the poco pays $0.04 plus the rate of $0.10 for the first 10 years and then rate thereafter? My electric bill shows my usage at 540kwh or 18kwh daily.
p.s. I also get a $1000 tva rebate along with the fed 30% credit.

My answer:
7kwh x 4h = 28kwh total gain, only 4 hours of sun here.
28kwh - 18kwh = 10kwh, net gain
10kwh x $0.14 = $1.40 x 30 = $42 monthly profit
18kwh x $0.10 = $1.80 x 30 = $54 monthly electric bill offset, meaning $0 bill.

$20,000 system
- $1000 rebate
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$19,000
- 30% fed credit
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$13,300 total payment
/ $42+$54 (96)
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138 months
/ 12 months
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12 years total payback which includes subtraction for the 1 year after the 4 cent premium expired.

Anybody can buy all the components for the above system including mounting system for about $10,000. One person can put this together inside a week, the wiring would take a day at most.
Besides a ground wire from the roof rack the only wiring from the panels are integral mechanically keyed snap together MC4 connectors that daisy chain all the panels to a single wire or a mix match depending on your system, truly a 5th grader could do this part.
I would disagree with some of what you said. If he is asking these simple questions how is he going to know what to buy? How will he know how to size his strings? What inverter to buy? Snapping MC connectors together is far from wiring a solar system. There is grounding of the system, conductor and breaker sizing not to mention the rules for dwellings and PV systems. I've wire a few systems and never have I seen a single wire PV panel, they all have a + and -. That's two if you only have one string. You didn't talk about rapid shutdown relays as required by 2014 NEC. Not one person has talked about inverter replacement( they have a 7 year average life). A 7kW system for $10,000. I don't think he will be able to find that pricing at 7000 watts.
 

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Discussion Starter #70
Electric_Light said:
http://www.dailyfinance.com/2014/06/11/is-your-credit-card-debt-average/ Credit cards are usually in double digit APR and the average American has a four figure credit card debt. Solar purchase should be avoided unless you owe absolutely zero on credit cards. Solar gives you no utility value (the only value is bill offset), so paying off credit cards will always have a better ROI. Solar sales, payday loan lenders, etc are fully aware of time value of money and they both know that cash flow is gold. If the commission and markup can be fully deferred for the full payback period for zero interest, they wouldn't show interest in selling solar. Payday advance seeks large interest for large mark up for immediate cash. Energy sales companies simply assign themselves zero interest payday loan in essence, because solar panels have no utility other than reducing the billable kWh and do not provide useful functions. So, the purchase of solar system gives energy sales people a cash advance for which the installed product pays back the lender very little at a time for a very long time. Sales people setup presentations to convince people believe something is a good deal and mocks your money as something that's sitting around in the corner unused but all he wants is to be able to walk out with it now and today. Most people value cash flow and liquidity. Solar is a great way to lock away money that you likely need soon and force you to borrow it, because you can't unlock the locked money. So, if you're someone who can see $10,000 to $30,000 the same way an average American sees as a quarter in his pocket, solar could possibly potentially work out.
After reading everyone's replys it seems to me that Solar Energy is to expensive for it to be worth it. Looks to me if you purchased the equipment and installed it yourself I guess it could be worth it untill you have to replace the 5-10K inverter. Almost like when leds bulbs were $50 a bulb and now there around $10, all the bullcrap saying they will last 20 years is croc of ****.
 

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Light Emitting Decoration
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After reading everyone's replys it seems to me that Solar Energy is to expensive for it to be worth it. Looks to me if you purchased the equipment and installed it yourself I guess it could be worth it untill you have to replace the 5-10K inverter. Almost like when leds bulbs were $50 a bulb and now there around $10, all the bullcrap saying they will last 20 years is croc of ****.
You need an extended warranty and insurance to cover losses due to power surge, hail, etc. These cost have to be rolled into the cost of ownership, thus requiring an even higher revenue stream to be financially sustainable.

PV solar is rich people's toy and bread and butter of the toy industry who feed the man toy industry. In contract, Mattel makes money from selling toys geared towards children. The difference is that who pays for it.

Usually, Mattel toys are paid out of pocket by parents. PV solar toys are generally paid in significant portions by you and I through taxes.
 

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1. The average ROI for a PV system in the US is 3-5 years. Unless your panels are orientated north, you have an inadequately sized system, or it is designed improperly, you will be within this range +/- 2 years.

2. In 20 years when your roof shingles need to be replaced, you dont need new panels. The panels and racking system can be removed and reinstalled. However, your roof shingles will last longer with the protection from panels and racking system.

Source: PV installer/Electrician and Published research in photovoltaics.
 
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