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Re: Math check: Purchasing panels wholesale
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Lu Wei
Dec 18, 2012, 9:29:17 PM12/18/12
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On 2012-12-17 9:00, William Bagwell wrote:
> Hi, I have been dreaming of solar since the late 80s and have been lurking here
> off and on for at least five years. Have watched prices slowly come down
> through the years and still can not afford more than a toy.
>
> Ran across an idea in a Slashdot post the other day that (if true) may be the
> means to finally afford a full system.
> http://hardware.slashdot.org/comments.pl?sid=3316801&cid=42287889
> Gist of it is that four or more home owners form an LLC and as a 'reseller' buy
> panels and such wholesale. If his math is correct my pay back could be well
> under 10 years even if I borrowed 100% of the cost. And half that if I could
> scrape up the cash. Hey, I can dream:-)
>
> Oh, in Georgia so leasing is out even if that made sense for me.
>
How much do they normally bid for a home solar system?
--
Regards,
Lu Wei
PGP key ID: 0x92CCE1EA
> Hi, I have been dreaming of solar since the late 80s and have been lurking here
> off and on for at least five years. Have watched prices slowly come down
> through the years and still can not afford more than a toy.
>
> Ran across an idea in a Slashdot post the other day that (if true) may be the
> means to finally afford a full system.
> http://hardware.slashdot.org/comments.pl?sid=3316801&cid=42287889
> Gist of it is that four or more home owners form an LLC and as a 'reseller' buy
> panels and such wholesale. If his math is correct my pay back could be well
> under 10 years even if I borrowed 100% of the cost. And half that if I could
> scrape up the cash. Hey, I can dream:-)
>
> Oh, in Georgia so leasing is out even if that made sense for me.
>
How much do they normally bid for a home solar system?
--
Regards,
Lu Wei
PGP key ID: 0x92CCE1EA
Message has been deleted
Lu Wei
Dec 21, 2012, 10:24:00 PM12/21/12
to
On 2012-12-20 9:12, William Bagwell wrote:
> out of the question, even half of that is in 'ain't never going to happen'
> territory. However, the poster on Slashdot indicated he got a system for 8 K
> that (reversing his math claims) started out in the 72 K range. If I could
> eliminate my electric bill forever for less than 8 K I would put it on plastic
> and be done with it.
>
> The calculators are not clear if the include the tax breaks. Tax breaks which
> vary from state to state and change every few years...
>
I'd like to know the on-line calculator you mentioned.
Let's do a rough calculation.
First, you should know your power demand: Assume a typical electricity
usage for a small family is 10kWh/day;
Second, the average equivalent standard sun hour per day of your place
(or kWh per kW produced a year): It varies much from place to place,
take California for example, is 5.2h;
So you need a system about 10kWh/5.2h ≈ 2kW.
Now comes the wondering part. As I know, the market price for PV module
now is about 0.8$/W. And module contributes about 40% in the cost of
system, so a system of 2kW should cost 0.8$/W / 0.4 * 2kW = 4k$. Assume
seller's profit is 20%, the price should be 4k$/(1-20%) = 5k$. What a
gap to 60k!
I do not include custom tariff -- it may be great due to anti-dumping
and anti-subsidy duties imposed -- and transportation cost. Maybe
someone else could help to estimate. But anyway I feel a number less
than 8k$ is reasonable in this example.
> On Wed, 19 Dec 2012 10:29:17 +0800, Lu Wei <luwe...@address.invalid> wrote:
>
>> How much do they normally bid for a home solar system?
>
> The on-line calculators I have tried have ranged up to 60 thousand. Absolutely
>
>> How much do they normally bid for a home solar system?
>
> out of the question, even half of that is in 'ain't never going to happen'
> territory. However, the poster on Slashdot indicated he got a system for 8 K
> that (reversing his math claims) started out in the 72 K range. If I could
> eliminate my electric bill forever for less than 8 K I would put it on plastic
> and be done with it.
>
> The calculators are not clear if the include the tax breaks. Tax breaks which
> vary from state to state and change every few years...
>
I'd like to know the on-line calculator you mentioned.
Let's do a rough calculation.
First, you should know your power demand: Assume a typical electricity
usage for a small family is 10kWh/day;
Second, the average equivalent standard sun hour per day of your place
(or kWh per kW produced a year): It varies much from place to place,
take California for example, is 5.2h;
So you need a system about 10kWh/5.2h ≈ 2kW.
Now comes the wondering part. As I know, the market price for PV module
now is about 0.8$/W. And module contributes about 40% in the cost of
system, so a system of 2kW should cost 0.8$/W / 0.4 * 2kW = 4k$. Assume
seller's profit is 20%, the price should be 4k$/(1-20%) = 5k$. What a
gap to 60k!
I do not include custom tariff -- it may be great due to anti-dumping
and anti-subsidy duties imposed -- and transportation cost. Maybe
someone else could help to estimate. But anyway I feel a number less
than 8k$ is reasonable in this example.
Message has been deleted
Lu Wei
Dec 25, 2012, 12:05:34 AM12/25/12
to
On 2012-12-24 9:29, William Bagwell wrote:
> ...
> http://www.findsolar.com/index.php?page=rightforme
> shows the below for 900kWh per month.
> ...
I think the data findsolar.com used may be outdated. It uses the same
calculation principle as me, yet adds one inefficiency discount of 80%,
which is better; but the most amazing parameter is $6/W system cost. As
I have pointed out the system cost should be not much greater than
$0.8/W /0.4 = $2/W; I can't imagine transportation cost and custom
tariff from China to US will push it towards $6, or there is surprising
profit. I'll write to the feedback mailbox to confirm.
> ...
> http://www.findsolar.com/index.php?page=rightforme
> shows the below for 900kWh per month.
> ...
I think the data findsolar.com used may be outdated. It uses the same
calculation principle as me, yet adds one inefficiency discount of 80%,
which is better; but the most amazing parameter is $6/W system cost. As
I have pointed out the system cost should be not much greater than
$0.8/W /0.4 = $2/W; I can't imagine transportation cost and custom
tariff from China to US will push it towards $6, or there is surprising
profit. I'll write to the feedback mailbox to confirm.
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