[p2p-research] Demystifying solar capacity

[Stan Rhodes]

I've split this email off to reduce the annoyance factor with
cross-posting.  I wanted to quickly clear up a few things regarding solar
power and units of energy given.  Forgive me, those of you that already know
this, and correct me if I made a mistake, those that know better.  Also,
math is involved to show my work, so you know where my numbers came from.

The output values being discussed are watt-peak output (Wp), meaning output
under ideal conditions, which is useless for assessing real power
generation.  Please see the following Wikipedia links:
http://en.wikipedia.org/wiki/Watt-peak
http://en.wikipedia.org/wiki/Capacity_factor

So, we can see capacity factor is the max output (Wp) divided by actual
output, meaning that if we only have the capacity factor and the max output
we should be able to multiply them to determine rough actual output.  I'll
do a quick example.

Look at the capacity factor of the world's largest PV power plants, shown in
the table on this page: http://en.wikipedia.org/wiki/Solar_power

Let's use the Waldpolenz Solar Park that uses newer "thin film" PV, like the
cells Nanosolar offers.  Notice how the values are given in DC MW.  To be
more precise, that should be MWp--peak output, not actual.  (Let's assume
the loss from converting DC to AC was included in the capacity factor to
make things easy.)

So, we do the math to determine actual output: 40 * .11 = 4.4 actual MW.
Convert to MWh per year: 4.4 MW * hours in a year (8766) = 38570.4 MWh.
Fact-check the table with that, and we see it's close: 38.5704 GWh/year
compared to 40 GWh/year.

As a rule of thumb, to find Nanosolar's thin-film cell cost per actual watt
output, divide cost per "watt"(Wp) by .11.*  .12 if you're feeling
generous.  Thus, $.30 per Wp actually costs $2.73 per W, or $2727 for a
setup that produces 1 kW on average.

The difference between MWp and actual MW output is the first vital
consideration when looking at solar claims.  The second is probably more
obvious: inherently variable solar (and wind) can't be used to replace
baseload plants like fossil fuel, nuclear, hydro, wood, geothermal, and
OTEC.  While nuclear capacity factors can be steadily improved--and have
been--it's hard to make many gains with solar and wind.  Fission and
combustion are far more steady than the weather.

-- Stan

* Not sure if this is clearer than saying to take the reciprocal of the
capacity factor and multiply by the price per Wp.  So, actual price per watt
= 1/Capacity Factor * price per Wp.  Math would be 1/.11 * $.30 = $2.73
actual price per watt.  Hope this makes sense.

On Sun, Jun 14, 2009 at 8:20 AM, Ryan Lanham <rlanham1963 at gmail.com> wrote:

> No, it isn't great news--yet.  Because you have to throw away old solar
> films and you have to glue them down and you have to replace them when they
> wear out.
> Nano has some exciting stuff, but you can't change the laws of physics.
>  The film technology discussion has been going on for a while and I'm sure
> it has some exciting technology, but to suggest it augers easy, cheap and
> readily available electricity is just hype...with very little likelihood of
> reality to back it up.
>
> What solar really needs is a skeptical NGO to attack the hype claims.
>
> Don't get me wrong, I'm for research and development where it makes sense.
>  But I am against industrial pollution, against systems that require
> constant replacement and which then fill landfills with horrible stuff, and
> I am against corporations making production claims they can never delivery
> (nuclear was supposed to be too cheap to meter!)
>
> I'd be willing to place a fairly large wager than solar photovoltaic will
> not be more than 10% of total energy production of the planet in the next
> 100 years.  I know it can't be executed, but I seriously doubt--highly doubt
> in the strongest terms--that solar is a player in the future of much
> importance.
>
> Cute toys for the rich and the know-nothing greens, maybe, serious human
> technology, I doubt.
>
> Ryan
>
>
> On Sun, Jun 14, 2009 at 3:09 AM, Vinay Gupta <hexayurt at gmail.com> wrote:
>
>>
>> Ryan,
>> Normal solar panel manufacturing cost is $2.30 a watt.
>>
>> Nanosolar claim $0.30 a watt (and are retailing for $1 a watt in
>> $1,000,000 quantities they say.)
>>
>> Konarka is claiming $0.10 a watt this year or next year.
>>
>> Dropping the price of solar seven to twenty times changes everything.
>> Anybody who's interested in the future owes it to themselves to get oriented
>> to this - it's the most important technological development since the
>> invention of the transistor, really. It means that in the future - within
>> one generation - electricity is going to be as information is now.
>>
>> Isn't that great news?
>>
>> Vinay
>>
>>
>> --
>> Vinay Gupta
>> Free Science and Engineering in the Global Public Interest
>>
>> http://bit.ly/flucode - please follow the Flu Code
>> if you are in a flu-effected area. It protects us all.
>>
>> http://guptaoption.com/map - social project connection map
>>
>> http://hexayurt.com - free/open next generation human sheltering
>>  http://hexayurt.com/plan - the whole systems, big picture vision
>>
>> Gizmo Project VOIP : (USA) 775-743-1851
>> Skype/Gizmo/Gtalk/AIM: hexayurt
>> Twitter: @hexayurt http://twitter.com/hexayurt
>> UK Cell : +44 (0) 0795 425 3533 / USA VOIP (+1) 775-743-1851
>>
>> "If it doesn't fit, force it."
>>
>> On Jun 14, 2009, at 2:08 AM, Ryan Lanham wrote:
>>
>> Vinay:
>> Thanks, you are probably right that my solar data is 2-3 years old--the
>> last time I had a real hard look.
>>
>> But I've also learned to not believe the marketing hype.  I have a number
>> of questions...
>>
>> 1. MTBF (Mean time between failure)
>> 2. Lifecycle costs on a significant-sized installation -- say, 75 KWe.
>>
>> I'd also like to know how they are holding the films down, with what, and
>> what they do with them when they are finished.
>>
>> Glad you are on it.  I'd love to be a fan of active solar.  As I said, the
>> last I looked, it wasn't very exciting.  Very small scale in very sunny
>> places--probably yes.  Else, not so much.
>>
>> Do please keep us informed of the data as it evolves.
>>
>> Ryan
>>
>> Ryan Lanham
>> rlanham1963 at gmail.com
>> Facebook: Ryan_Lanham
>>
>>
>>
>> On Sat, Jun 13, 2009 at 2:31 PM, Vinay Gupta <hexayurt at gmail.com> wrote:
>>
>>>
>>> Ryan,
>>> I suggest you _go and look at the data_ - Nanosolar is claiming 30 cents
>>> per watt of panel (manufacturing cost) for a retail of $1. They sold about a
>>> billion dollars of panels last year - this is not a lab operation.
>>>
>>> Konarka is claiming ten cents per watt of panel capacity with panels
>>> shipping later this year at a substantially higher price.
>>>
>>> Even with conservative assumptions about the mapping from raw panel price
>>> to price per kilowatt hour, this works.
>>>
>>> You're a few years out of data on solar, as far as I can tell.
>>>
>>> Vinay
>>>
>>>
>>> --
>>> Vinay Gupta
>>> Free Science and Engineering in the Global Public Interest
>>>
>>> http://bit.ly/flucode - please follow the Flu Code
>>> if you are in a flu-effected area. It protects us all.
>>>
>>> http://guptaoption.com/map - social project connection map
>>>
>>> http://hexayurt.com - free/open next generation human sheltering
>>>  http://hexayurt.com/plan - the whole systems, big picture vision
>>>
>>> Gizmo Project VOIP : (USA) 775-743-1851
>>> Skype/Gizmo/Gtalk/AIM: hexayurt
>>> Twitter: @hexayurt http://twitter.com/hexayurt
>>> UK Cell : +44 (0) 0795 425 3533 / USA VOIP (+1) 775-743-1851
>>>
>>> "If it doesn't fit, force it."
>>>
>>> On Jun 13, 2009, at 8:24 PM, Ryan Lanham wrote:
>>>
>>> Highly unlikely.  I think something like .50 cents a kilowatt hour is
>>> more likely-and that would be cheap.  The price is obviously set against the
>>> standard of nuclear which is almost universally given as 11 cents / kW-h.
>>> Coal is generally set a 5 cents.
>>>
>>> The film plastics are going to have all sorts of problems--getting rid of
>>> them is one.  Making them in scale is another.  They will require glues and
>>> epoxies everywhere to be set down.  More chemicals.  More run off risks.
>>>
>>> Anything under 25 cents a kW-h is attractive.  So far, solar isn't close.
>>>
>>> Nuclear would be about 3 cents a kW-h except for extremely high
>>> regulatory costs.
>>>
>>> The simple truth is that all forms of solar decay in the sun.  Plastic
>>> will decay too.  Efficiencies will drop and radiation will play havoc with
>>> electronics.  Solar isn't a very smart idea for large scale applications and
>>> it will wear out far too quickly for economical small scale applications.
>>> Plus you need weird chemicals.
>>>
>>> Ryan
>>>
>>>
>>> On Sat, Jun 13, 2009 at 1:08 PM, Vinay Gupta <hexayurt at gmail.com> wrote:
>>>
>>>>
>>>> http://nanosolar.com http://konarka.com
>>>> fundamentally, plastic solar is way cheaper than coal and it's going to
>>>> be the dominant energy generation method in the future, barring something
>>>> cheaper - and at $0.10 per watt of capacity (from Konarka's projections)
>>>> that's a per kilowatt hour cost a few percent that of current cheap coal...
>>>>
>>>> it's very, very radical stuff. I do think everybody playing this game
>>>> needs to be fully aware of what's coming from the plastic solar guys.
>>>>
>>>> Vinay
>>>>
>>>>
>>>>
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