Solar panel efficency
in [Design]
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From: Don Lancaster on 11 Jun 2010 18:26 On 6/9/2010 2:50 AM, JosephKK wrote: > On Sat, 05 Jun 2010 12:11:32 +1000, Sylvia Else<sylvia(a)not.here.invalid> > wrote: > >> On 5/06/2010 10:41 AM, Bill Bowden wrote: >>> On Jun 3, 8:16 pm, John Larkin >>> <jjlar...(a)highNOTlandTHIStechnologyPART.com> wrote: >>>> On Thu, 3 Jun 2010 20:00:24 -0700 (PDT), Bill Bowden >>>> >>>> >>>> >>>> <wrongaddr...(a)att.net> wrote: >>>>> On Jun 2, 11:55 pm, Martin Brown<|||newspam...(a)nezumi.demon.co.uk> >>>>> wrote: >>>>>> On 03/06/2010 00:39, Bill Bowden wrote: >>>> >>>>>>> On Jun 2, 8:45 am, Don Lancaster<d...(a)tinaja.com> wrote: >>>>>>>>> There are many sources claiming net (solar panel) energy >>>>>>>>> payback is far greater than the energy cost of production. >>>> >>>>>>>> These claims are utterly bogus as they treat subsidies as assets, rather >>>>>>>> than as much larger "iceberg" liabilities. The key issue is addressed at >>>>>>>> <http://www.tinaja.com/whtnu10.asp#d05-31-10> >>>> >>>>>>>>> And I know people in the business making a good living at it. >>>> >>>>>>>> So do I. Including the few remaining honest pioneers that have all the >>>>>>>> arrows in their backs. And when you get them drunk enough or stoned >>>>>>>> enough, they freely admit they are stealing federal and state dollars >>>>>>>> just like everybody else does. >>>> >>>>>>>> <http://www.tinaja.com/blig/nrglect2.pdf> >>>> >>>>>>>> -- >>>>>>>> Many thanks, >>>> >>>>>>>> Don Lancaster voice phone: (928)428-4073 >>>>>>>> Synergetics 3860 West First Street Box 809 Thatcher, AZ 85552 >>>>>>>> rss:http://www.tinaja.com/whtnu.xmlemail: d...(a)tinaja.com >>>> >>>>>>>> Please visit my GURU's LAIR web site athttp://www.tinaja.com >>>> >>>>>> Junk science. >>>> >>>>>>> Well that's nice. Now if you can just give me a couple other >>>>>>> references, not written by you, I will be a believer. >>>> >>>>>> That isn't going to happen. Although the myth that solar panels never >>>>>> pay back their energy investment is widespread. They may never pay back >>>>>> the cost to make, install and use them over their lifetime, but that is >>>>>> an entirely different matter. And the economics is shifting as someone >>>>>> demonstrated there appear to be panels on the market now at $2/W. >>>> >>>>>>> Here's another one you don't want to read. >>>> >>>>>>> http://en.wikipedia.org/wiki/Photovoltaics >>>> >>>>>>> "Energy payback time and energy returned on energy invested >>>> >>>>>>> The energy payback time is the time required to produce an amount of >>>>>>> energy as great as what was consumed during production. The energy >>>>>>> payback time is determined from a life cycle analysis of energy. The >>>>>>> energy needed to produce solar panels is paid back in the first few >>>>>>> years of use.[79] >>>> >>>>>>> Another key indicator of environmental performance, tightly related to >>>>>>> the energy payback time, is the ratio of electricity generated divided >>>>>>> by the energy required to build and maintain the equipment. This ratio >>>>>>> is called the energy returned on energy invested (EROEI). This should >>>>>>> not be confused with the economic return on investment, which varies >>>>>>> according to local energy prices, subsidies available and metering >>>>>>> techniques. >>>> >>>>>>> Life-cycle analyses show that the energy intensity of typical solar >>>>>>> photovoltaic technologies is rapidly evolving. In 2000 the energy >>>>>>> payback time was estimated as 8 to 11 years,[80] but more recent >>>>>>> studies suggest that technological progress has reduced this to 1.5 to >>>>>>> 3.5 years for crystalline silicon PV systems.[74] >>>> >>>>>>> Thin film technologies now have energy pay-back times in the range of >>>>>>> 1-1.5 years (S.Europe).[74] With lifetimes of such systems of at least >>>>>>> 30 years[citation needed], the EROEI is in the range of 10 to 30. They >>>>>>> thus generate enough energy over their lifetimes to reproduce >>>>>>> themselves many times (6-31 reproductions, the EROEI is a bit lower) >>>>>>> depending on what type of material, balance of system (or BOS), and >>>>>>> the geographic location of the system.[81] " >>>> >>>>>> You can't always trust Wiki but there is also stuff in the peer reviewed >>>>>> literature that refute his bogus claim (which to be fair might once have >>>>>> been true decades ago when solar cells were *much* thicker). >>>> >>>>>> See Richards& Watt (2007) >>>> >>>>>> http://www.inference.phy.cam.ac.uk/sustainable/refs/solar/Myth.pdf >>>> >>>>>> Regards, >>>>>> Martin Brown >>>> >>>>> Interesting article. Also found this article about a 250MW solar >>>>> project by a SCE in the southern California area. Must have some value >>>>> if SCE wants to build it. >>>> >>>> California utilities are required to get a portion of their power from >>>> renewables. They might not if the decision were purely economic. >>>> >>>> John >>> >>> How about hydro-electric which qualifies as renewable. Why waste time >>> with solar if economics are better with hydro? Or is this a dumb >>> question? >>> >>> -Bill >> >> The economics of hydro are good, if there's a suitably place to build >> one. Suitable means that the topography and rainfall have to be >> appropriate, and it's mustn't be too far from the place where the power >> will be used. >> >> Sylvia. > > The distance to usage point is no where as significant as you think. They > ship hydropower electric from Washington state to LA and San Diego, over > 1000 miles with recently built infrastructure. Total average shipping loses are under seven percent. And not currently that big a deal. -- Many thanks, Don Lancaster voice phone: (928)428-4073 Synergetics 3860 West First Street Box 809 Thatcher, AZ 85552 rss: http://www.tinaja.com/whtnu.xml email: don(a)tinaja.com Please visit my GURU's LAIR web site at http://www.tinaja.com
From: Don Lancaster on 11 Jun 2010 18:29 On 6/9/2010 3:04 AM, Martin Brown wrote: > > Again being seen to do something may get brownie points even if it isn't > particularly effective. Be interesting to see the numbers. > The numbers are rather scary. <http://www.tinaja.com/whtnu09.asp#d06-16-09> -- Many thanks, Don Lancaster voice phone: (928)428-4073 Synergetics 3860 West First Street Box 809 Thatcher, AZ 85552 rss: http://www.tinaja.com/whtnu.xml email: don(a)tinaja.com Please visit my GURU's LAIR web site at http://www.tinaja.com
From: Don Lancaster on 11 Jun 2010 21:57 On 6/9/2010 3:21 AM, Dirk Bruere at NeoPax wrote: > On 09/06/2010 11:04, Martin Brown wrote: >> On 05/06/2010 03:11, Sylvia Else wrote: >>> On 5/06/2010 10:41 AM, Bill Bowden wrote: >>>> On Jun 3, 8:16 pm, John Larkin >>>> <jjlar...(a)highNOTlandTHIStechnologyPART.com> wrote: >>>>> On Thu, 3 Jun 2010 20:00:24 -0700 (PDT), Bill Bowden >>>>> <wrongaddr...(a)att.net> wrote: >>>>>> On Jun 2, 11:55 pm, Martin Brown<|||newspam...(a)nezumi.demon.co.uk> >>>>>> wrote: >> >>>>>>> You can't always trust Wiki but there is also stuff in the peer >>>>>>> reviewed >>>>>>> literature that refute his bogus claim (which to be fair might once >>>>>>> have >>>>>>> been true decades ago when solar cells were *much* thicker). >>>>> >>>>>>> See Richards& Watt (2007) >>>>> >>>>>>> http://www.inference.phy.cam.ac.uk/sustainable/refs/solar/Myth.pdf >>>>> >>>>>> Interesting article. Also found this article about a 250MW solar >>>>>> project by a SCE in the southern California area. Must have some >>>>>> value >>>>>> if SCE wants to build it. >>>>> >>>>> California utilities are required to get a portion of their power from >>>>> renewables. They might not if the decision were purely economic. >> >> I suspect that is true, but it may not hold for too much longer if >> screen or inkjet printable semiconductors become stable enough to be >> worth using in this application. Or some other thin film PV trick. > > Since Nanosolar claim that they can now manufacture PV for $0.70 per > peak watt, and it's currently selling at around $2, it gives an > indication of the scope for prices falling when supply finally exceeds > demand by a large margin. The key being economy of scale. > The fastest way to drop the price is to eliminate the subsidies. -- Many thanks, Don Lancaster voice phone: (928)428-4073 Synergetics 3860 West First Street Box 809 Thatcher, AZ 85552 rss: http://www.tinaja.com/whtnu.xml email: don(a)tinaja.com Please visit my GURU's LAIR web site at http://www.tinaja.com
From: Dirk Bruere at NeoPax on 12 Jun 2010 13:04 On 10/06/2010 20:59, Martin Brown wrote: > On 10/06/2010 20:41, Mark wrote: >> On Jun 9, 5:58 pm, Paul Keinanen<keina...(a)sci.fi> wrote: >>> On Wed, 09 Jun 2010 21:29:52 +0100, Martin Brown >>> >>> <|||newspam...(a)nezumi.demon.co.uk> wrote: >>>> On 09/06/2010 20:54, Paul Keinanen wrote: >>>>> At higher latitudes (Central and Northern Europe), the peak >>>>> consumption is during the winter months, with minimal solar >>>>> production. During the summer months, when the solar production is >>>>> high, the consumption is low (and nuclear power plants are shut down >>>>> for annual maintenance during the summer) and hence the price that you >>>>> can get from the solar electricity is quite low. >>> >>>> I agree. PV is a dead loss at our latitude since it hardly generates >>>> anything at all in the dull grey winters. To my amazement though in the >>>> bleak midwinter on the few sunny days with blue skies my friends 2kW PV >>>> array generates about 800W despite the low midday solar elevation of >>>> just 26 degrees. >>> >>> Thus the zenith distance would be 64 degrees. >>> >>> At Christmas, the solar declination is -23.5 degrees, >>> >>> Thus, your friend must be living at 40.5 degrees latitude (Barcelona, >>> Athens) latitude. >>> >>> In Spain, there are several solar thermal electric powerplants in the >>> few megawatt class. >> >> you will know when solar PV have "made it" (become economical) when >> you see the factory that makes them, has them on the roof and doesn't >> use much power from the grid.. > > That is an excessive requirement. It becomes worthwhile when the total > energy payback on solar is 10-100x that of manufacture. At the moment it > is around 6-8x for PV and rising so there is hope for it yet. nanosolar claim an energy payback time of 1 month -- Dirk http://www.transcendence.me.uk/ - Transcendence UK http://www.blogtalkradio.com/onetribe - Occult Talk Show
From: Dirk Bruere at NeoPax on 12 Jun 2010 13:05
On 11/06/2010 04:02, Bill Bowden wrote: > On Jun 9, 3:21 am, Dirk Bruere at NeoPax<dirk.bru...(a)gmail.com> > wrote: >> On 09/06/2010 11:04, Martin Brown wrote: >> >> >> >>> On 05/06/2010 03:11, Sylvia Else wrote: >>>> On 5/06/2010 10:41 AM, Bill Bowden wrote: >>>>> On Jun 3, 8:16 pm, John Larkin >>>>> <jjlar...(a)highNOTlandTHIStechnologyPART.com> wrote: >>>>>> On Thu, 3 Jun 2010 20:00:24 -0700 (PDT), Bill Bowden >>>>>> <wrongaddr...(a)att.net> wrote: >>>>>>> On Jun 2, 11:55 pm, Martin Brown<|||newspam...(a)nezumi.demon.co.uk> >>>>>>> wrote: >> >>>>>>>> You can't always trust Wiki but there is also stuff in the peer >>>>>>>> reviewed >>>>>>>> literature that refute his bogus claim (which to be fair might once >>>>>>>> have >>>>>>>> been true decades ago when solar cells were *much* thicker). >> >>>>>>>> See Richards& Watt (2007) >> >>>>>>>> http://www.inference.phy.cam.ac.uk/sustainable/refs/solar/Myth.pdf >> >>>>>>> Interesting article. Also found this article about a 250MW solar >>>>>>> project by a SCE in the southern California area. Must have some value >>>>>>> if SCE wants to build it. >> >>>>>> California utilities are required to get a portion of their power from >>>>>> renewables. They might not if the decision were purely economic. >> >>> I suspect that is true, but it may not hold for too much longer if >>> screen or inkjet printable semiconductors become stable enough to be >>> worth using in this application. Or some other thin film PV trick. >> >> Since Nanosolar claim that they can now manufacture PV for $0.70 per >> peak watt, and it's currently selling at around $2, it gives an >> indication of the scope for prices falling when supply finally exceeds >> demand by a large margin. The key being economy of scale. >> > > And there are also slightly broken, chipped solar cells for sale on > ebay or http://solarcells101.com/ for about 73 cents a cell (about 1/2 > watt each) or maybe $1.45 a watt if you buy 100. They all work 95%, > just have small chips on the corners and sides. Each cell is about 1.2 > amps at 400mV optimum load. > There are some real PV bargains around for engineers who are into DIY solar. -- Dirk http://www.transcendence.me.uk/ - Transcendence UK http://www.blogtalkradio.com/onetribe - Occult Talk Show |