Solar panel efficency
in [Design]
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From: Tim Watts on 10 Jun 2010 16:15 On Thu, 10 Jun 2010 13:07:57 -0700, BlindBaby <BlindMelonChitlin(a)wellnevergetthatonethealbumcover.org> wibbled: > On Thu, 10 Jun 2010 20:59:22 +0100, Martin Brown > <|||newspam|||@nezumi.demon.co.uk> 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. >> >>OTOH at my latitude where the sun barely makes 12 degrees above the >>horizon at midday in mid winter PV is pretty useless. The PV powered >>"warning bend - skid hazard" roadsigns tend to die a horrible death >>every winter if they are not totalled first by some speeding nutter. >> >>Kind of sad really - they work brilliantly all summer when there is no >>frost and lots of sunshine and as soon as winter comes they run out of >>battery power about an hour after sundown even on sunny days. >> >>Regard, >>Martin Brown > > > They should put little wind motors (generators) on them too then. They do round here (southern England). PV + a little windmill to light up a sign that I have never seen lit in the 100's of times I have passed it. Could probably have stuck some lithium batteries in it and still have it good for 5 years! -- Tim Watts Managers, politicians and environmentalists: Nature's carbon buffer.
From: BlindBaby on 10 Jun 2010 16:22 On Thu, 10 Jun 2010 20:15:54 +0000 (UTC), Tim Watts <tw(a)dionic.net> wrote: > >Managers, politicians and environmentalists: Nature's carbon buffer. Can we use them to sop up the oil then?
From: Michael A. Terrell on 10 Jun 2010 18:14 Tim Watts wrote: > > They do round here (southern England). PV + a little windmill to light up > a sign that I have never seen lit in the 100's of times I have passed it. > Could probably have stuck some lithium batteries in it and still have it > good for 5 years! Those fools in Brussels should have never shut down their Energizer Bunny breeding farm... -- Anyone wanting to run for any political office in the US should have to have a DD214, and a honorable discharge.
From: Tim Watts on 10 Jun 2010 18:52 On Thu, 10 Jun 2010 18:14:50 -0400, "Michael A. Terrell" <mike.terrell(a)earthlink.net> wibbled: > Tim Watts wrote: >> >> They do round here (southern England). PV + a little windmill to light >> up a sign that I have never seen lit in the 100's of times I have >> passed it. Could probably have stuck some lithium batteries in it and >> still have it good for 5 years! > > > Those fools in Brussels should have never shut down their Energizer > Bunny breeding farm... One got mixi, so Farmer Rumpey had the lot shot ;-> -- Tim Watts Managers, politicians and environmentalists: Nature's carbon buffer.
From: BlindBaby on 10 Jun 2010 19:08
On Thu, 10 Jun 2010 18:14:50 -0400, "Michael A. Terrell" <mike.terrell(a)earthlink.net> wrote: > >Tim Watts wrote: >> >> They do round here (southern England). PV + a little windmill to light up >> a sign that I have never seen lit in the 100's of times I have passed it. >> Could probably have stuck some lithium batteries in it and still have it >> good for 5 years! > > > Those fools in Brussels should have never shut down their Energizer >Bunny breeding farm... Idiot. There is only one Energizer Bunny. |