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California schools $120M solar project

Discussion in 'Home Power and Microgeneration' started by amdx, May 31, 2010.

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  1. amdx

    amdx Guest

    Yesterday I heard a radio story about the California School district
    spending $120 million to put solar energy in/on schools.
    I did a Google search and can't find any info.
    The numbers I heard didn't seem cost effective,
    so I'm curious.
    Anybody know more about it?
  2. PeterD

    PeterD Guest

    I believe they gave $119 million to Al Gore's efforts, and spent the
    remaining million on publicity.
  3. Bill

    Bill Guest

    Actually quite "cost effective" for a school!

    Many schools are "building rich" and "operating budget" poor. That is they
    can easily find millions and millions of dollars to build new buildings -
    and this money can only be spent on that.

    Yet they can't find enough money to pay day to day expenses. They might have
    trouble coming up with an extra $5 for blackboard chalk. Seriously!

    So quite smart of them to use that construction money for something like
    solar which would reduce their day to day expenses. Perhaps they will be
    able to buy chalk in the future?

    "amdx" wrote in message
  4. Sylvia Else

    Sylvia Else Guest

    I don't believe in these alleged economies of scale. Solar panels
    already represent a large industry. The economies of scale, such as they
    are, have already been obtained.

  5. amdx

    amdx Guest

    That thought did come to mind. I'm hopeful that we (the people) are taking
    the power that the constitution says we have and telling our reps it's time
    to cut the spending. When our reps stop having town meetings because
    the people are angry, that is a change.
    November is coming, please support candidates that believe in the ideas
    that provided a great standard of living in 200 years.
    Limited government, freedom, liberty and property rights.
    That property rights is a getting to be big. Getting so you can't dig a hole
    your own property and in PC Fl. It's is a $1000 fine to cut down a pine tree
    over a certain diameter, on YOUR* property.
    Government and the environmentalist are out of control.

    * If you can call it yours, try not paying that rent.
    Also known as property tax.
    end of rant.
  6. vaughn

    vaughn Guest

    Not so, especially not so at the consumer level. At the consumer level PV
    panels remain a nitch product, so lack of retail competition and huge shipping
    costs because of a lack of any local distribution channel presents significant

  7. nospam

    nospam Guest

    Depends on what value you place on brainwashing children.

    They put windmills on schools which won't generate enough electricity to
    cover maintenance costs never mind installation but the children get to see
    a big eco green tree hugging bollocks symbol every day......
  8. amdx

    amdx Guest

    I think your wrong!
    The producers are very angry at government overspending.
    But we have to many sucking the tit probably don't care.
    give me give me.

    Apples and oranges.
  9. Joerg

    Joerg Guest

  10. vaughn

    vaughn Guest

    That is still $5.00 per watt, and then you STILL have to pay for shipping.
    There are far better deals to be had, but shipping can be a deal killer.(See )

    My point was that you can probably find several places within driving distance
    to buy (say) roofing materials, but you will be lucky to find even one place
    that stocks a variety of PV panels. That one place will have no completion, so
    no reason to offer you the best deal. When you buy a heavy/bulky item from a
    local vender, it has likely arrived by the pallet load via a bulk shipper. Then
    you just pick it up and take it home, or pay a small amount to have your order
    delivered the "last mile".. When you buy that same heavy/bulky item from a
    remote retailer, they have to custom pack it, and then send you your order via
    an expensive retail shipper. That huge expense at the end of the distribution
    chain KILLS any economy of scale that may have occurred earlier. The consumer
    will rarely get a fair shake until an item truly becomes part of the mass

  11. Martin Brown

    Martin Brown Guest

    Some element of price gouging unless they are fancy ones.
    $4/W is about where it starts to get interesting. But PV is pretty much
    a none starter economically unless you get some kind of install grant
    and a ludicrous price for the electricity generated. And yes there are
    fraudsters "generating" way more "solar" electricity than the PV array
    they installed could possibly manage (even on cloudy days). It took the
    suits in charge of the green refunds a while to catch on...

    One thing I will say was that I was surprised how well they did on on a
    cold clear winters day in the UK. The cold more or less compensated for
    the low angle sun and the array managed nearly 50% of rated output.

    Martin Brown
  12. tm

    tm Guest

    Seriously, would you trust a Harbor Freight solar cell? I don't buy
    anything from that store that needs to plug into the mains.

    George W. Bush had an honorable discharge and proved to be the dumbest
    **** ever to hold a political office. 'nuff said for your sig.

    UNTIL Obama!
  13. vaughn

    vaughn Guest

    Suit yourself! I am happy to have a Harbor Freight near me, but I recognize
    that they sell mostly crap. Fortunately; for light duty and occasional use,
    crap is sometimes good enough.

    I have seen their PV panels and decided to taka a pass in favor of a much better
    quality panel.

  14. :

    It appears to me that Philadelphia gets year-round-average insolation
    of 175 watts, at least 170 per square meter. Compare that to the 1 KW
    per square meter that I have some impression that solar cell arrays are
    rated at...

    That sounds to me like 34-47 dollars per watt in Philadelphia, if the
    panels are laid horizontally.

    I am guesstimating that by making them facing 40 degrees south of zenith
    (towards "high noon" sun on days of the equinoxes), an improvement of 40%
    of the 30.5% high-noon-equinox improvement would be achieved on
    year-round-average. Maybe tilt them to face 37-38 degrees south of zenith
    because the sun is up and out more in the spring and summer than in the
    fall and winter. Maybe tilt them to face 2-3 degrees north of the
    celestial equator and 7.5 degrees east of "high noon meridian" to take
    advantage of the fact that on average during daytime there are more clouds
    after noon than before. (I am aware of "morning fog / foggy low cloud"
    exceptions to this "general rule"). At this rate, I expect about a 15%
    improvement by optimizing how the solar panels are aimed. Without further
    optimization to motorize them and get them to track the sun.

    So, I see good opportunity of a Philadelphian to get the cost down to
    $29.50-$41 per watt.

    Considering that a Philadelphian pays nowadays about 14.5 cents per KWH
    of electricity at "residential rate", excluding the surcharge for
    consumption past 750 KWH (I hope I got that right, too lazy at this
    moment to dig out a recent electric bill) per month during a defined air
    conditioning season.

    At this rate, even a Philadelphian who wears nice cool summer dresses in
    the house and uses fans rather than air conditioners and tolerates
    subtropical to often-worse-hot weather well and frets more about winter
    than summer and who lives in a rowhouse (good for stealing some climate
    control from any more-climate-control-needy next-door neighbors) would
    have a $29.50-41-per-watt solar panel paying for itself in 41 / .000145
    hours, which works out to...

    About 23-32 years, assuming inflation in electricity cost is the same as
    inflation of cost of cost of whatever else a homemaker has to pay. If one
    does all maintenance required and in the likely event the solar panel and
    the likely-associated DC-AC inverter (at maybe 90% efficiency) keeps on
    truckin', then it's 25-35 years to pay for itself, and 50-100 years to
    double the invested money.
    Suppose sun tracking with at least one motor is deployed, at consumption
    of 5% of the output of the solar panel. At that rate, I have liking for:

    Philadelphia above atmosphere year-round-average appears to me to
    achieve about 315-320 watts per square meter of insolation, while at
    ground level appears to me to achieve 170-175 watts per square meter.
    That makes me think "at this rate" that 1 KW per square meter of direct
    sunlight is degraded to 530-555 watts per square meter of a solar panel
    that tracks the sun, before loss from electrical power consumption of
    devices to track the sun and before correction for maybe 40% of the time
    there is significant cloud cover that at least mostly destroys
    optimization of sun-tracking (as a "representative figure").

    At this rate, I have a liking for 95% of 60% of the way from 175 to 320
    watts per square meter to be divided by 175 watts per square meter...
    42% improvement of rate of return, down to 70.3% as much time to get
    money back to you - as in about 16-22.5 years to pay for itself, or about
    32-45 years to double your money should you have no expense at maintaining
    the system that long.
    (If the system requires rechargeable batteries, plan on additional
    expense because such bateries have a high rate of expiring in less than 32
    or even 16 years.)

    If you double your inflation-adjusted money in 16.6667 years, then the
    annual rate of return is 3% above the effectively-actual inflation rate.

    I seem to think that the total rate of returns of major stock index
    funds, especially "total stock market" ones, have done better from 1970 to
    now or would have if they were in operation according to their stated
    rules should they have been in existence in 1970 - I would guess likely
    even in UK, let alone USA! For that matter, fair chance even from the
    roughly-1970 high to the 2009 low! (second-worst 39 years of USA stock
    market - behind the 39 year stretch starting at or a bit before the 1929
    high. I seem to think that stretch had USA total stock market outpacing
    "official inflation" by 4-5% with reinvestment of dividends, minus the
    ~.3% annual expense ratio that a good index fund like Vanguard "Index
    Total" should have and that Vanguard achieves.)
  15. Guest

    Where'd you get that impression? Here's a typical module.
    ~135W per sq. meter.

  16. Only arguably for one specific office of one of 2-3 brances and
    3-to-often-4 levels of government where both level and branch exists and
    where the office in question is one voted into by voters.

    I seem to think that Philadelphia has elected some mayors that would
    make the bumber of the 2 bushes look like an outright brainiac in
    comparison. I even remember one November election between two that some
    called "airhead vs. vacuum", and occaisionally as the one to choose which
    of the two worst prior mayors of Philadelphia to put back into that

    Let alone elections for the 17 councilcritters (unicameral legislative
    branch) for Philadelphia... Where 10 are elected from districts, and 7
    are elected "at-large" (on citywide basis as opposed to representing a
    district of the city), with Philly's city charter having an "affirmative
    action program" to limit to 5 of these 7 being in the same political
    party. Post-1949, Philadelphia has usually had 14-15 Democrats and 2-3
    Republicans in their legislative branch of gubmint.

    And it appears to me that most Philadelphia councilcritters leave office
    by dying in office, retiring at a very old age, need to go to prison, or
    due to racial change of a district that they have to be re-elected from.
    And when the councilcritters worse than the mayor mismanage the
    government of the city (despite a "strong mayor" city charter), their
    constituents tend to blame the mayor.


    From before Civil War to sometime around or a bit before 1950, the
    contentedly corrupted Philadelphians tended to employ stinky awful
    Republican mayors. Then, they elected a good Democrat mayor, followed by
    a fairly/somewhat good Democrat mayor, and after that to now sent to City
    Hall Democrat mayors that wre/are at best were so-so (in my opinion) and
    at worst (in my opinion) stank even more than the worst Republican mayor
    that Philadelphia ever endured.

    I seem to think that Philadelphians often elect and re-elect local
    government officers worse than every President that USA ever had.
  17. In <>,
    My experience in and near Philadelphia is that school days are centered
    around noon or less than an hour before noon.

    Keep in mind that on average, cloudiness is worse after noon than before
    even in Philadelphia with their few days per year clouded by "morning fog"
    or "morning foggy low clouds".
  18. On Tue, 01 Jun 2010 17:18:57 -0700
    Probably from reading the specs and knowing about the typical
    efficiency of PV cells. The output rating of PV cells is usually quoted
    under "full sun" conditions of around 1000 W per sq. metre.
    That's the electrical output of that panel, which given the normal
    efficiency of panels like that (10-15%) means an insolation of around 1000 W
    per sq. meter. Actually the specs for that panel claim 13.1% efficiency so
    slightly over 1000 W per sq. metre is required to achieve that output.
    Not so - those were pretty accurate calculations.

    Of course if you want efficient use of solar energy then solar
    thermal is the way to go - it's not too hard to get 70-80% of the
    insolation energy available as usable heat.
  19. Guest

    No kidding?
    If Klipstein mounts one of the modules I referenced above in full sun
    in Philly on a cool day and measures the output, he'll conclude that
    it costs out at ~$2 per Watt, not the $30-$40 he managed to arrive at.
    To avoid starting with worst case PV costs he could google "best price
    PV". And he could skip even more GIGO by using HOMER or some such. Which would prevent erroneous assumptions such
    as his 5% of production for tracking. Seriously? Try ~20Whrs per day,
    which on a 1000W array in Philly might net out to ~.5% minus for the
    motor, but >20% plus overall. PV economics aren't great, especially if
    one is willing to ignore the unbilled-cost of grid energy and the
    unsustainability of the billed cost. So those who seek to be negative
    about the economics really don't need to exaggerate.

  20. Martin Brown

    Martin Brown Guest

    That is their price per peak output per watt installed and seems
    unusually low. $4/W is still about the going rate and some are closer to
    $8/W where you paying a premium for higher efficiency.

    But unless you can arrange continuous sunlight the average output over
    the year allowing for clouds and including diffuse light is something
    like 1/8 to 1/10 of peak installed capacity. So his $30-40/W delivered
    for use is basically in the right ballpark in the long term.

    Operating at peak efficiency with a clear sky and normal incidence
    sunlight then the array can achieve peak performance, but the rest of
    the time it does not by a long way. And obviously at night it is idle.
    I think you just have to be clear about what measure you are using.

    The PV array link you pointed at is the cheapest I have seen on offer -
    has anyone here obtained one? Or are they vapourware?

    Martin Brown
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