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Residential solar power

  1. Sep 3, 2011 #1
    I am having my home evaluated by a SunRun, Home Depot and bpsolar consortium. There was a booth in a Home Depot store in NJ.

    The "deal in brief": I supply the roof area for solar and they get permits, build,install, maintain and pay for the entire solar system. Then they sell me power under a 20 year contract at a discount to PSE&G power. Unless I have to modify my roof or replace shingles, there is no out of pocket expenditure for me.

    Anybody done this with any companies?? Any experience with this particular offering??

    Suggestions or recommendations???

    (Apparently commercial installations get accelerated depreciation allowances not available to homeowners.)
    Last edited: Sep 3, 2011
  2. jcsd
  3. Sep 4, 2011 #2
    The Home Depot sales rep told me that many townships consider the addition of solar roof panels as equivalent to a second layer of shingles.....and many only permit two layers. So if there are already two layers of shingles, they would have to be removed and a new single layer installed before the solar installation. That is at the homeowners cost.

    I will post what I learn here during the evaluation and engineering inspection process. Obviously I'm not committed until I see the contract and financial numbers.

    Are solar installations included in tax assessments??
  4. Sep 4, 2011 #3
    The Home Depot Rep gave me two financial statistics, :
    (1) PSE&G electric rates have been increasing about 6% annually,
    (2) SREC rates have dropped from around $500 or $600 dollars to about $150 greatly extending the payback period of owner installed systems

    From my Electric bills from PSE&G:
    August 2011 18.5 cents per KWH
    August 2010 18.3 cents
    August 2009 18.9 cents
    August2008 18.8 cents
    August 2007 17.0 cents
    August 2006 15.2 cents

    so roughly 18.5/15.2 is about a 21.7% increase over 5 years....closer to 4% than the 6% he quoted. No increase last three years!!!!

    As to the SREC rates:
    This site

    shows NJ rates in the $600 dollar range dropping dramatically ....to $167???? Can there be that many solar installations as to cut rates by 2/3???? This confirms what the Home Depot rep told me.

    For those interested in first hand information Home Depot has this website: www.homedepot.com/sunrun...have[/URL] to check it out myself.
    Last edited by a moderator: Apr 26, 2017
  5. Sep 4, 2011 #4
    Will you have an option to purchase the equipment at the end of the 20 year agreement - sounds like a lease arrangement?
  6. Sep 4, 2011 #5


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    Yes. The old rate was by far the highest in the country. If solar made sense anywhere, then it made sense in NJ.
  7. Sep 4, 2011 #6

    jim hardy

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    The Home Depot link didn't work for me.

    from the SREC page, http://srectrade.com/background.php
    "3. Penalty for Non-Compliance: Finally, in order to have a robust SREC market, your state must implement some sort of fine or penalty for non-compliance. This is commonly known as a solar alternative compliance payment (SACP). The SACP is what drives the values of SRECs above any other type of REC. Without the SACP, it is difficult to incentivize buyers to pay prices that promote solar growth."

    So gov't is forcing everyday citizens to to subsidize this through their utility bill.
    It reeks of Al Gore and goes against my principles.
    Thank goodness the rate dropped.

    I hope it works for you but read the fine print.
    Particularly as to who bears cost of maintenance,
    and what rights of access to your property they require.

    old jim
  8. Sep 5, 2011 #7
    I agree on all points.
    I did not want to bring up ethical/political issues in an electrical engineering discussion forum but I posted similar "subsidy" comments just now in the other big solar thread...."Should I invest in Solar now"...which is 13 pages long at the moment.

    I just might reject any installation on ethical grounds myself but I want to know the current technology and economics anyway.

    Right now, if SREC rates have dropped dramatically, why would any company continue to invest in solar...and why offer me a discount from regular rates?? I'll post what I find.
  9. Sep 5, 2011 #8
  10. Sep 5, 2011 #9
    From an insurance perspective, I see a problem with the roof. Even if the project requires a new 20+ year roof be installed prior to installation, the equipment could cause the roof to leak after years of wind resistance. The homeowners policy would more than likely not cover damages and would shift the burden onto the equipment owner.
  11. Sep 5, 2011 #10
    That does seem like a possibility. I'll have to look at the installation height off the roof and see what load is estimated for high winds and what wind speeds the panels withstand. If it's one foot height, I would not do it; if a few inches, additional wind resistance should be minimal. You've made me think contacting my insurance company before any decision is a good idea.

    I've been told Home Deport warranties against leaks for ten years, but again I have to see the actual contract fine print. I also plan to ask the roof contractor if they have heard of problems with solar panel fastenings causing leaks. I'd be more worried about

    The 25 and 30 year caulks, not the traditional black creosote smelling roof caulks, stay pliable in even freezing weather and should not be a problem if utilized.
  12. Sep 5, 2011 #11

    jim hardy

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    ""?????????? ""

    indeed http://www.njcleanenergy.com/renewab...g/srec-pricing [Broken] doesn't show a price decrease
    but this link you posted earlier http://srectrade.com/srec_prices.php
    at least predicts one - look at NJ 2011-2012 line it goes down pretty drastically
    i got there by clicking "historical pricing" on the SRECTRADE prices page

    i echo your ?????????????

    ""I did not want to bring up ethical/political issues in an electrical engineering discussion forum..... ""
    believe me i hesitated.....
    thanks for the other forum i'll check it out

    my thinking is : looks like the middleman's cut is around 5% from those pages
    and presumably he is rewarded by gov't for pushing green power via tax incentives
    or maybe even direct DOE grants to get the stuff built.
    What does he provide me in exchange? A slight discount on my electricity?
    And now i must write one check to my utility for their meter and another to SREC for my kilowatts?

    I'd study that deal before signing up.
    Which it sounds like you are doing.

    I'm very interested in how this works out.

    I am almost ready to build myself a flat panel solar water heater
    because heating water is majority of my electrical consumption
    and that i can do with very simple, inexpensive equipment
    and no contracts or monthly fees or paperwork.
    Wish i'd done it when copper was $2 a pound - i thought that was too high then.

    The science here is simple - if i'm to have a panel up there it's gonna heat water directly from sunlight not indirectly via electricity made with <10% efficient solar cells and sold back to me.

    old jim
    Last edited by a moderator: May 5, 2017
  13. Sep 7, 2011 #12
    I e-mailed my August electric rates to he Home Depot Sales rep and he replied as follows:

    "yes, I did say they had gone up 5-6% annually (on average). Here is the link to the US Government site I used to quote that

    in table 8 you will see it has gone up more. Again, it is just an average for the state for the years 2005 thru 2009. I will be back to you later today with some additional information. Best, Bill"

    I have a new computer which will not open this data so I have not seen it....but I really don't care all that much what it says; I care what is actually in my bill.

    I also e-mailed the local roofers who did my roof about 15 years ago for a remove and reshingle estimate in preparation for solar panels. Hurricane Irene just passed NJ and I imagine it will be a while before they come to inspect.
  14. Sep 10, 2011 #13
    9/10/11 update,
    Met with the Home Depot Rep (HDR) and got preliminary figures: He estimated my annual electric usage at 10,700 KWH using my own electric bills. I am proceeding with them for further analysis at no obligation.

    Remember SunRun pays for and installs , owns, operates and maintains the solar system on my roof. My out of pocket costs for the system is $0.

    The initial electric rate I would pay from SunRun (solar) is 12.3 cents/kwh versus the current utility rate of 18.5 cents, a 33% discount. The rate would increase 2.9% annually. I asked if there was any contractual protection against that annual increase exceeding PSE&G rates.....he will check.

    He will provide me another option at my request: one in which SunRun sells me electricity at the same 33% discount from PSE&G rates, whatever they may be, for the entire 20 years. I like that concept but will have to see what they offer.... It elimnates SREC market and solar legislative risk.

    He estimated that instead of my first year PSE&G bill of about $1,987, I would pay SunRun about $1154 and PSE&G $251, for a first year saving of $582. He gave me a 20 year projection which I'm not going to bother posting in detail: supposedly savings increase each year and total about $33,000 over 20 years

    HDR said his system would provide about 9,400 kwh of my total 10,700 kwh annual usage. I told him that sounded impossible since he can only provide power from maybe 9AM to 5PM (as an example)....What about the rest of the day?? We could not resolve that: so I told him I'd discuss this with the engineer who comes to do the actual site and engineering analysis. [I don't think my power from roughly 5PM all night to 9AM (when solar production is at a minimum] would be covered by $251 payment to PSE&G....especially when some rain and snow days may produce insufficient power for my daytime usage. ]

    An option is that if I prepay $25,323 SunRun will provide power without any annual increase in rate....that is, at 12.3 cents per KWH for 20 years. That produces a 20 years savings of almost $64,000; thats an additional $31,000 saving over 20 years relative to their sole ownership on my roof ....not a very interesting saving.

    There are several purchase options which I'm not going to describe since I don't want the upfront costs. One involves them keeping the SREC ownership which could be interesting who doubt future government support.

    I asked: What happens if SunRun goes bankrupt, and, for example, a hurricane damages the system making it inoperable. He will check as I said I wanted something to cover situations like that in the contract.

    The HDR agreed solar is uneconomical without government incentives. HDR agreed to provide me some residential; references in the area..people who have systems operating...one is about five years old.

    Note: I talked with my city tax assessor: Unless the company owning the solar system pays me rent, which they do NOT, there is no tax assessment.....so no extra property taxes.
    Last edited: Sep 10, 2011
  15. Sep 11, 2011 #14
    I understand that when commercial power is lost, most solar installations do not provide any
    solar power to the home.

    Is this correct and why??
    Can't they install a switch to disconnect the home from the grid? Such a switch IS available\and required when using an emergency generator at home.
  16. Sep 11, 2011 #15


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    By that statement the vendor likely means that during the middle of the day your solar array would produce several times more power than you use on average. The vendor either intends to push that excess power out to the grid (for a price, perhaps via SRECs) and draw from the grid at other times, or store the midday power in battery storage system.
  17. Sep 12, 2011 #16
    I tried maybe three questions to draw that out...clearly the guy doesn't understand technical details... I asked him exactly that.....There was insufficient electrical data (which most people would not even understand) in his presentation to make a determination. He told me the 9,400 annual kwh was what I would be using...so as noted above, I'll have to save that issue for the engineer's site evaluation visit.
  18. Sep 13, 2011 #17
    jim hardy:
    That may be the best solution for water heating...I don't know. But I do know one thing: you have not made a case either way. Remember, I am not paying for the solar system, so if you lay out,say, $10,000 bucks and get a more "efficient" water heating system, it may take a looooong time to recover your investment. That should be your criteria.

    Your other comment:
    appears skeptical, which is ok, but unsubstantiated. Those are among the very issues I am investigating and sharing in this discussion.

    I have not made up my mind either way yet, but so far I am still interested. For me the key issue may be first cost of removing and replacing roof shingles in order to save (preliminary saving estimate) about $1,200 over two years, maybe $1,800 over three.

    Note: I tallied up the annual savings provided in the HDR analysis and they total the $33,153 I posted earlier which means the analysis given me did NOT discount cash flows. Since the biggest saving are out in the future [based on their PSE&G rate increase assumptions] this grossly overstates present values. But since I am outlaying minimal money up front, I don't care all the much.
    Last edited: Sep 13, 2011
  19. Sep 14, 2011 #18
    I was checking some Home Depot solar equipment to get a feel for costs and power of solar generation and came across this, an "1800 watt" solar package for $1499:


    Thats less than a dollar a watt!!!!!! installed cost and is impossible.

    So reading the specs shows it produces 12 amps at 12 volts....and the "140" watt spec seems right for a panel 27" x 58"....

    So what could the headline "1800 watts" really be? I figured it's really daily watt hours...but that would require the full 140 watts power for 1800/140 or 12.9 hours which seems wildy optimistic....Any other insights??

    For some fun, look at the comments submitted at the above website about this product!!
    Last edited by a moderator: Apr 26, 2017
  20. Sep 14, 2011 #19


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    Though the title of the ad is misleading, the "1800W" rating is clearly defined in the text: it is the power rating for the DC to AC inverter, charge controller, and auto transfer switch electronics. That's a decent price at $1500. Large scale inverters (only) are about $0.75/Watt. One 140W polySi photovoltaic panel is included, the only 'solar' aspect to the package. If someone could scrounge ten 180W panels+mounting somewhere and handle the installation (big if), this Home Depot package is all that's required to run a residential system.
    Last edited by a moderator: Apr 26, 2017
  21. Sep 14, 2011 #20
    Oh yea, that IS clearly stated in the DESCRIPTION...thanks....

    What an unusual combination for the typical consumer...A single 140 watt solar panel, no battery, and a huge inverter relative to the single solar panel provided.

    Another 9 panels from Home Depot (185 watts at $399 each) and you can actually produce about 1800 watts. Thats about $1,500 plus $3,600 or $5,100/1800 watts or about $2.83 material first cost.

    How does a solar power system like this interface with a home electrical panel?? It's can't be allowed to provide power to the grid during a power failure because of the danger to repairmen.
    Last edited: Sep 14, 2011
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