Reply by Winston February 9, 20122012-02-09
VWWall wrote:

(...)

> I recently found out what happened to my 1960 Jaguar: > > http://www.fantasyjunction.com/cars/1103-Jaguar-XK150%203.8%20FHC-3.8%20Litre%20Inline%206-Cylinder
Wow! Nice looking car, Virg!
> "More recently, a more advanced Pertronix ignition system has been installed, and the twin 6V batteries have replaced > with top of the line Optima units...."
One assumes the batteries they replaced were not >34-year-old factory parts! :) --Winston
Reply by Phil Hobbs February 9, 20122012-02-09
On 02/09/2012 07:50 PM, VWWall wrote:
> VWWall wrote: >> Jim Thompson wrote: >>> On Wed, 21 Dec 2011 20:21:49 GMT, Ralph Barone >>> <address_is@invalid.invalid> wrote: >>> >>>> Jim Thompson <To-Email-Use-The-Envelope-Icon@On-My-Web-Site.com> wrote: >>>>> On Tue, 20 Dec 2011 20:41:45 -0800, Winston <Winston@BigBrother.net> >>>>> wrote: >>>>> >>>>>> Jim Thompson wrote: >>>>>> >>>>>> (...) >>>>>> >>>>>>> An amusing thought, make a smart charger that bypasses some charging >>>>>>> current around the "better" unit until leveling is accomplished. >>>>>>> >>>>>>> Solution left as an exercise for the student :-) >>>>>> You are joshing, but I wonder if the electrical >>>>>> characteristics of a relatively discharged >>>>>> battery vs those of a charged battery could be >>>>>> used to that end. Ferinstance, is there a >>>>>> pulse waveform that would be ignored by the >>>>>> charged battery but would tend to charge the >>>>>> 'flatter' battery connected to it in series? >>>>>> >>>>>> Hrm. >>>>>> >>>>>> --Winston >>>>> Would I josh ?:-) >>>>> >>>>> How does the voltage regulator in your car work? It tailors the >>>>> current to match a voltage profile versus temperature. >>>>> >>>>> Just make a shunt that works oppositely. >>>>> ...Jim Thompson >>>> I suspect a high accuracy, sharp kneepoint, current limited zener (or >>>> equivalent, of course) would be all that you need. >>> >>> Something like that, but accomplished with comparators, and other >>> "smarts". You have to track temperature. >>> ...Jim Thompson >> >> My 1957 Jaguar XK150 had a 12V, (positive ground), electrical system. > <1960> > >> This was made up of two 6V lead-acid batteries, one under the fender >> of each front wheel. These were charged, (and discharged), in series >> with no problems. The only difficulties I experienced were in showing >> a AAA tow-truck driver how to hook up for a jump-start. :-) >> > I recently found out what happened to my 1960 Jaguar: > > http://www.fantasyjunction.com/cars/1103-Jaguar-XK150%203.8%20FHC-3.8%20Litre%20Inline%206-Cylinder > > > "More recently, a more advanced Pertronix ignition system has been > installed, and the twin 6V batteries have replaced with top of the line > Optima units...." >
Nice. It's two weeks younger than I am, and I wish I looked that good. ;) Cheers Phil Hobbs -- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC Optics, Electro-optics, Photonics, Analog Electronics 160 North State Road #203 Briarcliff Manor NY 10510 845-480-2058 hobbs at electrooptical dot net http://electrooptical.net
Reply by VWWall February 9, 20122012-02-09
VWWall wrote:
> Jim Thompson wrote: >> On Wed, 21 Dec 2011 20:21:49 GMT, Ralph Barone >> <address_is@invalid.invalid> wrote: >> >>> Jim Thompson <To-Email-Use-The-Envelope-Icon@On-My-Web-Site.com> wrote: >>>> On Tue, 20 Dec 2011 20:41:45 -0800, Winston <Winston@BigBrother.net> >>>> wrote: >>>> >>>>> Jim Thompson wrote: >>>>> >>>>> (...) >>>>> >>>>>> An amusing thought, make a smart charger that bypasses some charging >>>>>> current around the "better" unit until leveling is accomplished. >>>>>> >>>>>> Solution left as an exercise for the student :-) >>>>> You are joshing, but I wonder if the electrical >>>>> characteristics of a relatively discharged >>>>> battery vs those of a charged battery could be >>>>> used to that end. Ferinstance, is there a >>>>> pulse waveform that would be ignored by the >>>>> charged battery but would tend to charge the >>>>> 'flatter' battery connected to it in series? >>>>> >>>>> Hrm. >>>>> >>>>> --Winston >>>> Would I josh ?:-) >>>> >>>> How does the voltage regulator in your car work? It tailors the >>>> current to match a voltage profile versus temperature. >>>> >>>> Just make a shunt that works oppositely. >>>> >>>> ...Jim Thompson >>> I suspect a high accuracy, sharp kneepoint, current limited zener (or >>> equivalent, of course) would be all that you need. >> >> Something like that, but accomplished with comparators, and other >> "smarts". You have to track temperature. >> >> ...Jim Thompson > > My 1957 Jaguar XK150 had a 12V, (positive ground), electrical system.
<1960>
> This was made up of two 6V lead-acid batteries, one under the fender of > each front wheel. These were charged, (and discharged), in series with > no problems. The only difficulties I experienced were in showing a AAA > tow-truck driver how to hook up for a jump-start. :-) >
I recently found out what happened to my 1960 Jaguar: http://www.fantasyjunction.com/cars/1103-Jaguar-XK150%203.8%20FHC-3.8%20Litre%20Inline%206-Cylinder "More recently, a more advanced Pertronix ignition system has been installed, and the twin 6V batteries have replaced with top of the line Optima units...." -- Virg Wall
Reply by josephkk January 5, 20122012-01-05
On Wed, 04 Jan 2012 19:34:56 +1100, omg@grrr.id.au wrote:

> >>http://www.thesolarguide.com/solar-energy-systems/grid-tie-inverters.as=
px
> >That's what I didn't remember the name of, yes. "A multi-function=20 >inverter is additionally connected to a battery bank and a standby=20 >generator. The battery bank allows you to store power to rely even=20 >less on conventional grid power sources." -- I think that confirms=20 >my opinion that these things stop when there's no mains, easier to=20 >regulate as well, no live islands (is there a word for that?) to=20 >blow away the power company workers repairing the dead power lines?
Yes, it is mandatory in the US for the grid-tie inverter to turn off in the event of mains brownout or loss. And it must not restart until manually restarted with normal power already present (though there may be exceptions to this).
> >Although here I notice a triplet of grounding cables clipped=20 >to high voltage lines when they're being worked on. Low voltage=20 >they work on from insulated cherry-pickers, even after turning=20 >off the power.=20 >>
Depends on the particular power company, locally i saw them replace power poles with 21kV 3 phase on top live. I was interesting how they rewired to the new poles and cross arms without disturbing the hot 21 kV circuit. All the really big kV circuits under load are done hot, sometimes with a helicopter dropping the line crew onto the line and letting them work. There is video on youtube. ?-)
Reply by Winston January 4, 20122012-01-04
omg@grrr.id.au wrote:
> On Wed, 04 Jan 2012 14:00:39 -0800, Winston<Winston@BigBrother.net> wrote:
(...)
>> Was that battery still functioning at capacity? > > I wish I'd tested for that before taking them back for disposal, > was too distracted by the immediate.
It's a puzzlement. (...)
> I was meaning that I suspect the grid-tie ones stop working when > there's no mains present to force inverter synchronisation?
I believe that there are grid-tie inverters that do rely on incoming power for synchronization but I also think there are inverters that can be configured to supply A.C. to an isolated installation without need of an external reference as well. The Kaco Model #KBP1502XI for example can be switched to grid feed mode or standalone mode. See p. 8: http://www.aimscorp.net/documents/KBP1502XI_manual.pdf
> No islanding issue, safe and useless to the home owner on a hot > bright day when power load shedding is happening.
We go about it another way. Solar power producers contract to sell power at 'avoided cost' rather than 'retail cost' to our power company. Guess which price is higher. :)
> Maybe you > don't have that over there? We've had the govt stalling on > power stations for years, stalling on dirty brown coal (very > large deposit in Victoria) to oil or gas conversion, yet > selling off gas resources overseas instead of doing import > replacement -- the power industry seems corrupt
No comment. (...)
>> Or thieves that steal PV panels. >> http://green.blogs.nytimes.com/2010/05/03/foiling-solar-bandits/ > > Are the panels expensive enough to warrant built in GPS locator > and mobile phone chips? Put a stolen one in the sun and it > reports back home, "Hey! I'm over here!". Probably too easy > to disable such a module, same for self disabling panels?
I think individual panels could possibly be 'bugged' though I've never heard of it happening.
> Even before PV panels, in outback .au Telecom had a problem > with diesel fuel theft, so the stuff is dyed. Fill pipe is > alarmed as well. Not far from here there's a hilltop repeater > powered by one of those slow old style donkey engines, poom, > poom, poom about twice per second?
Very nifty. --Winston
Reply by January 4, 20122012-01-04
On Wed, 04 Jan 2012 14:00:39 -0800, Winston <Winston@BigBrother.net> wrote:

>omg@grrr.id.au wrote: >> On Tue, 03 Jan 2012 20:59:02 -0800, Winston<Winston@BigBrother.net> wrote: >> >>> omg@grrr.id.au wrote: > >(...) > >>> I haven't done the experiment but I'd bet that >>> a floated SLA would benefit from occasional rehydration. >> >> Well, several years ago my friend who handles lots of SLAs >> dropped four brand new ones off for me to play with, put >> a couple into an ancient UPS, not so good. So for several >> years these four 12V SLA batteries set in a row connected >> to a float charger to keep them okay. Funny thing is about >> a year ago I was using these batteries to power a project, >> swapping it with another as required to charge it again. >> >> One day I notice a split down one side of a 7AH battery, I >> look around, no sign of the expected acid leak, not under >> the battery, nor in the cracked case, looked like a pressure >> split. The batteries never been over-volted, the matching >> battery was bulging same spot too. It's a mystery, the >> battery guy just shrugged, said they run virtually dry >> these days. > >Was that battery still functioning at capacity?
I wish I'd tested for that before taking them back for disposal, was too distracted by the immediate.
> >>> See? Here is where your managerial, organizational >>> skills will make you a ton of money. >> >> If I had any ;) > >An expert is just a drip under pressure. :)
I know, I fell apart working ten years for a boss applying that pressure to me. Haven't work full time since. Painted myself into a tiny specialised corner, no way out at the time.
>
...
>Battery systems can be configured for 'islanding' or 'non-islanding' >use. >http://en.wikipedia.org/wiki/Islanding
I was meaning that I suspect the grid-tie ones stop working when there's no mains present to force inverter synchronisation? No islanding issue, safe and useless to the home owner on a hot bright day when power load shedding is happening. Maybe you don't have that over there? We've had the govt stalling on power stations for years, stalling on dirty brown coal (very large deposit in Victoria) to oil or gas conversion, yet selling off gas resources overseas instead of doing import replacement -- the power industry seems corrupt
> >> Although here I notice a triplet of grounding cables clipped >> to high voltage lines when they're being worked on. Low voltage >> they work on from insulated cherry-pickers, even after turning >> off the power. > >Sounds safer. > >(...) > >>> I guess any machine has it's environmental 'challenges'. >> >> Like the birds that chew on windscreen wiper blades, or crap >> on solar panels, weigh down and bend TV antennas. > >Or thieves that steal PV panels. >http://green.blogs.nytimes.com/2010/05/03/foiling-solar-bandits/
Are the panels expensive enough to warrant built in GPS locator and mobile phone chips? Put a stolen one in the sun and it reports back home, "Hey! I'm over here!". Probably too easy to disable such a module, same for self disabling panels? Even before PV panels, in outback .au Telecom had a problem with diesel fuel theft, so the stuff is dyed. Fill pipe is alarmed as well. Not far from here there's a hilltop repeater powered by one of those slow old style donkey engines, poom, poom, poom about twice per second? Grant.
> >--Winston
Reply by Winston January 4, 20122012-01-04
omg@grrr.id.au wrote:
> On Tue, 03 Jan 2012 20:59:02 -0800, Winston<Winston@BigBrother.net> wrote: > >> omg@grrr.id.au wrote:
(...)
>> I haven't done the experiment but I'd bet that >> a floated SLA would benefit from occasional rehydration. > > Well, several years ago my friend who handles lots of SLAs > dropped four brand new ones off for me to play with, put > a couple into an ancient UPS, not so good. So for several > years these four 12V SLA batteries set in a row connected > to a float charger to keep them okay. Funny thing is about > a year ago I was using these batteries to power a project, > swapping it with another as required to charge it again. > > One day I notice a split down one side of a 7AH battery, I > look around, no sign of the expected acid leak, not under > the battery, nor in the cracked case, looked like a pressure > split. The batteries never been over-volted, the matching > battery was bulging same spot too. It's a mystery, the > battery guy just shrugged, said they run virtually dry > these days.
Was that battery still functioning at capacity?
>> See? Here is where your managerial, organizational >> skills will make you a ton of money. > > If I had any ;)
An expert is just a drip under pressure. :)
>> Contract with the owner to remove the panels and >> contract with your mates to do the disassembly >> and cleanup. Easy! (GD&R) > > Okay, yes, right, thank you...
Don't mention it. (...)
>>> Yes, perhaps they want the dust to settle and reduce the heat >>> loading. Or maybe it'll blow off like the Mars Rovers? >> >> Well, that is not the best plan I ever heard of. :) > > Yes, but they cconvinced somebody to put up the money, probably > arguing what colour to paint the poles or something?
Well, at least us taxpayers didn't foot the.... Hey, Wait A Minute! (...)
>> Lots of folks run 'batteryless'. >> They connect the panels to their synchronous inverter >> and spin their power meter backwards. A higher voltage >> would sure be warranted, in that pursuit. >> >> http://www.thesolarguide.com/solar-energy-systems/grid-tie-inverters.aspx > > That's what I didn't remember the name of, yes. "A multi-function > inverter is additionally connected to a battery bank and a standby > generator. The battery bank allows you to store power to rely even > less on conventional grid power sources." -- I think that confirms > my opinion that these things stop when there's no mains, easier to > regulate as well, no live islands (is there a word for that?) to > blow away the power company workers repairing the dead power lines?
Battery systems can be configured for 'islanding' or 'non-islanding' use. http://en.wikipedia.org/wiki/Islanding
> Although here I notice a triplet of grounding cables clipped > to high voltage lines when they're being worked on. Low voltage > they work on from insulated cherry-pickers, even after turning > off the power.
Sounds safer. (...)
>> I guess any machine has it's environmental 'challenges'. > > Like the birds that chew on windscreen wiper blades, or crap > on solar panels, weigh down and bend TV antennas.
Or thieves that steal PV panels. http://green.blogs.nytimes.com/2010/05/03/foiling-solar-bandits/ --Winston
Reply by January 4, 20122012-01-04
On Tue, 03 Jan 2012 20:59:02 -0800, Winston <Winston@BigBrother.net> wrote:

>omg@grrr.id.au wrote: >> On Tue, 03 Jan 2012 07:14:44 -0800, Winston<Winston@BigBrother.net> wrote: >> >>> omg@grrr.id.au wrote: > >(...) > >> Dodo advertises "Dodo, for Internet that flies" So I put up >> "dodo, for Internet that dies" top of my web pages -- that got >> up management's nose? Dunno, eventually they fixed the faulty >> border router, they had two tech savvy customers locate the >> thing for them (tcptraceroute) run from an outside server. > >Good on ya. >Sounds like a fun bug to squash.
Yes, convincing a windows shop that unix and the Internet go hand in hand. That some users do have a clue. But when you think of all the average Joe's that kicked modem plug out of the socket or something? No wonder they outsource customer service first and second levels.
> >> It's wonderful how I digress from charging a pair of 6V >> batteries on a 12V charger, yes, you can put a pair or more >> LA batteries in a series string, onto the same charger. >> >> You can even charge LA batteries in parallel, it is better >> for new batteries than charging them in series. not so easy >> in equipment, and not enough benefit to do a switching >> circuit. Though I did that for a pair of 100AH batteries, >> which was fine until I miswired a dual battery connector, >> plugged it in, heard that lovely DC high current hiss >> before the 35A battery fuses blew, lost an Anderson >> connector, welded mated! > >Drama: Not Good. :) > > >>> Next: Battery and charger circuit! >> >> Little stuff, hang a float charger off the same 19V DC >> supply to a laptop? Yes, I know float charging can >> cause corrosion, it's the race between corrosion (over- >> charge) and sulphation (undercharge) that kills standby >> SLA batteries. Hmm, water loss shouldn't be an issue >> for SLAs in standby service. They're supposed to have >> some recombinant methods built in to address that. > >I haven't done the experiment but I'd bet that >a floated SLA would benefit from occasional rehydration.
Well, several years ago my friend who handles lots of SLAs dropped four brand new ones off for me to play with, put a couple into an ancient UPS, not so good. So for several years these four 12V SLA batteries set in a row connected to a float charger to keep them okay. Funny thing is about a year ago I was using these batteries to power a project, swapping it with another as required to charge it again. One day I notice a split down one side of a 7AH battery, I look around, no sign of the expected acid leak, not under the battery, nor in the cracked case, looked like a pressure split. The batteries never been over-volted, the matching battery was bulging same spot too. It's a mystery, the battery guy just shrugged, said they run virtually dry these days.
> > >>> Have a team available to do the salvage and cleanup! >> >> If it happens there's lots from the bush blocks wanting >> the things ;) > >See? Here is where your managerial, organizational >skills will make you a ton of money.
If I had any ;)
>Contract with the owner to remove the panels and >contract with your mates to do the disassembly >and cleanup. Easy! (GD&R)
Okay, yes, right, thank you...
> >>> A local community college has installed US$11.3 million >>> worth of photovoltaics, covering parking areas. >>> They are at 37 degrees latitude. The panels are not >>> angled toward the sun, but face straight up! >>> http://www.mercurynews.com/sunnyvale/ci_19453056 >> >> Silly, you're supposed to put them up at closer to the >> winter angle for maximum performance year round. > >Well, *I* know that and *you* know that. >They don't know that, apparently. > > >> Wisdom around here on the bush blocks is that tracking the sun >> is not worth the complexity, put in an extra fixed panel. >> Google Earth tells me I'm at 36&#2013266106;45' (South). >> >> Maybe they figured the loss of efficiency plus increase >> of flat facing panels dust collection made some sense? >> >> The Cat in the Hat solution? > >Oh those? Those'r "dust collectors". >We don't have any solar panels. > >>> http://tiny.cc/2q1t1 or: >>> <http://extras.mnginteractive.com/live/media/site568/2011/1201/20111201__scup1202solar~1_GALLERY.JPG> >>> >>> This picture looks straight south. there isn't even a way >>> to point the panels normal to the sun! >> >> Google Earth has it as of June 20, 2011, 'Fly to' >> >> "De Anza College Solar Panel Project" >> >> and zoom in, hard to miss. >> >>> >>> An architectural triumph, perhaps. >> >> Yes, shade between the panels moves with the sun, keeping the >> cars cooked evenly? From the Google Earth image, looks like >> it's on top of a building? > >The first installation was on top of a 'parking structure' >(Garage). Later, the large parking lot to it's north and east >got the same treatment. > >>> An efficiency nightmare, definitely. >> >> Yes, perhaps they want the dust to settle and reduce the heat >> loading. Or maybe it'll blow off like the Mars Rovers? > >Well, that is not the best plan I ever heard of. :)
Yes, but they cconvinced somebody to put up the money, probably arguing what colour to paint the poles or something?
> >>>> I speak only for the crazy case of a temporary crash on >>>> used solar panel prices as people discard ever realising >>>> the vague promise of some RoI in their lifetimes :) >>> >>> I think a manufacturer would be more likely to >>> warehouse or destroy panels rather than sell >>> them for half the cost of manufacture. >> >> And retarget the panels for low voltage use. Things wired >> to supply several hundred volts for direct conversion to our >> 230VAC mains. Who wants to run a 100 or 120 cell battery >> bank? Even the phone companies chose 24 cell (48V) as highest >> spanner burning current but lowest direct lethality, easily a >> tingle. > >Lots of folks run 'batteryless'. >They connect the panels to their synchronous inverter >and spin their power meter backwards. A higher voltage >would sure be warranted, in that pursuit. > >http://www.thesolarguide.com/solar-energy-systems/grid-tie-inverters.aspx
That's what I didn't remember the name of, yes. "A multi-function inverter is additionally connected to a battery bank and a standby generator. The battery bank allows you to store power to rely even less on conventional grid power sources." -- I think that confirms my opinion that these things stop when there's no mains, easier to regulate as well, no live islands (is there a word for that?) to blow away the power company workers repairing the dead power lines? Although here I notice a triplet of grounding cables clipped to high voltage lines when they're being worked on. Low voltage they work on from insulated cherry-pickers, even after turning off the power.
> >> So we got any old house[1] with these things bolted on, high >> voltage special DC connectors -- I was stunned into disbelief >> when I saw what they doing for economy. Corrosion, summer >> heat, winters below freezing overnight, okay we don't get >> snow, but lots of dew in the mornings for half of the year. >> >> Lower voltage, standby battery option and a boost converter >> would add not much to the cost for safer panel installation. >> >> [1] Weatherboard construction with a tin (well painted, rusty >> galvanised iron) roof I saw within walking distance of here. >> >> Then there's critters like possums and birds nesting may do >> some damage, or rats nibbling on the HVDC cables in the roof >> space > >I guess any machine has it's environmental 'challenges'.
Like the birds that chew on windscreen wiper blades, or crap on solar panels, weigh down and bend TV antennas. Cheers, Grant.
> >--Winston
Reply by Winston January 4, 20122012-01-04
omg@grrr.id.au wrote:
> On Tue, 03 Jan 2012 07:14:44 -0800, Winston<Winston@BigBrother.net> wrote: > >> omg@grrr.id.au wrote:
(...)
> Dodo advertises "Dodo, for Internet that flies" So I put up > "dodo, for Internet that dies" top of my web pages -- that got > up management's nose? Dunno, eventually they fixed the faulty > border router, they had two tech savvy customers locate the > thing for them (tcptraceroute) run from an outside server.
Good on ya. Sounds like a fun bug to squash.
> It's wonderful how I digress from charging a pair of 6V > batteries on a 12V charger, yes, you can put a pair or more > LA batteries in a series string, onto the same charger. > > You can even charge LA batteries in parallel, it is better > for new batteries than charging them in series. not so easy > in equipment, and not enough benefit to do a switching > circuit. Though I did that for a pair of 100AH batteries, > which was fine until I miswired a dual battery connector, > plugged it in, heard that lovely DC high current hiss > before the 35A battery fuses blew, lost an Anderson > connector, welded mated!
Drama: Not Good. :)
>> Next: Battery and charger circuit! > > Little stuff, hang a float charger off the same 19V DC > supply to a laptop? Yes, I know float charging can > cause corrosion, it's the race between corrosion (over- > charge) and sulphation (undercharge) that kills standby > SLA batteries. Hmm, water loss shouldn't be an issue > for SLAs in standby service. They're supposed to have > some recombinant methods built in to address that.
I haven't done the experiment but I'd bet that a floated SLA would benefit from occasional rehydration.
>> Have a team available to do the salvage and cleanup! > > If it happens there's lots from the bush blocks wanting > the things ;)
See? Here is where your managerial, organizational skills will make you a ton of money. Contract with the owner to remove the panels and contract with your mates to do the disassembly and cleanup. Easy! (GD&R)
>> A local community college has installed US$11.3 million >> worth of photovoltaics, covering parking areas. >> They are at 37 degrees latitude. The panels are not >> angled toward the sun, but face straight up! >> http://www.mercurynews.com/sunnyvale/ci_19453056 > > Silly, you're supposed to put them up at closer to the > winter angle for maximum performance year round.
Well, *I* know that and *you* know that. They don't know that, apparently.
> Wisdom around here on the bush blocks is that tracking the sun > is not worth the complexity, put in an extra fixed panel. > Google Earth tells me I'm at 36&#2013266106;45' (South). > > Maybe they figured the loss of efficiency plus increase > of flat facing panels dust collection made some sense? > > The Cat in the Hat solution?
Oh those? Those'r "dust collectors". We don't have any solar panels.
>> http://tiny.cc/2q1t1 or: >> <http://extras.mnginteractive.com/live/media/site568/2011/1201/20111201__scup1202solar~1_GALLERY.JPG> >> >> This picture looks straight south. there isn't even a way >> to point the panels normal to the sun! > > Google Earth has it as of June 20, 2011, 'Fly to' > > "De Anza College Solar Panel Project" > > and zoom in, hard to miss. > >> >> An architectural triumph, perhaps. > > Yes, shade between the panels moves with the sun, keeping the > cars cooked evenly? From the Google Earth image, looks like > it's on top of a building?
The first installation was on top of a 'parking structure' (Garage). Later, the large parking lot to it's north and east got the same treatment.
>> An efficiency nightmare, definitely. > > Yes, perhaps they want the dust to settle and reduce the heat > loading. Or maybe it'll blow off like the Mars Rovers?
Well, that is not the best plan I ever heard of. :)
>>> I speak only for the crazy case of a temporary crash on >>> used solar panel prices as people discard ever realising >>> the vague promise of some RoI in their lifetimes :) >> >> I think a manufacturer would be more likely to >> warehouse or destroy panels rather than sell >> them for half the cost of manufacture. > > And retarget the panels for low voltage use. Things wired > to supply several hundred volts for direct conversion to our > 230VAC mains. Who wants to run a 100 or 120 cell battery > bank? Even the phone companies chose 24 cell (48V) as highest > spanner burning current but lowest direct lethality, easily a > tingle.
Lots of folks run 'batteryless'. They connect the panels to their synchronous inverter and spin their power meter backwards. A higher voltage would sure be warranted, in that pursuit. http://www.thesolarguide.com/solar-energy-systems/grid-tie-inverters.aspx
> So we got any old house[1] with these things bolted on, high > voltage special DC connectors -- I was stunned into disbelief > when I saw what they doing for economy. Corrosion, summer > heat, winters below freezing overnight, okay we don't get > snow, but lots of dew in the mornings for half of the year. > > Lower voltage, standby battery option and a boost converter > would add not much to the cost for safer panel installation. > > [1] Weatherboard construction with a tin (well painted, rusty > galvanised iron) roof I saw within walking distance of here. > > Then there's critters like possums and birds nesting may do > some damage, or rats nibbling on the HVDC cables in the roof > space
I guess any machine has it's environmental 'challenges'. --Winston
Reply by January 3, 20122012-01-03
On Tue, 03 Jan 2012 07:14:44 -0800, Winston <Winston@BigBrother.net> wrote:

>omg@grrr.id.au wrote: >> On Mon, 02 Jan 2012 15:31:26 -0800, Winston<Winston@BigBrother.net> wrote: >> >>> omg@grrr.id.au wrote: >>>> On Sun, 01 Jan 2012 23:34:45 -0800, Winston<Winston@BigBrother.net> wrote: > >(...) > >> Yeah, we paying heaps for casual (prepaid) access here, >> alternative is to sign up for two year contracts that run >> quite expensive with trick advertised rates and extra >> charges in the fine print. The 'ombudsman' paid for by >> the industry (TIO) is overloaded with complaints, but is >> funded by those complaints -- very odd system? > >How does that work? >Do you send in a cheque with each complaint? >That sounds screwy.
Oh no, the TIO bill each ISP on the basis of complaints against them, tens of bux for the first complaint through to thousands for a complaint not resolved in some specified timeframe, for example and ISP has ten business days to address a complaint, then it's escalated to level 2 when the ombudsman gets involved. First level gives a direct technical contact number to call ISP -- generally ISPs own level three complaints handling. ISPs may outsource "customer service" to Manila, so there's much anger in talking to people who have no idea of technical issues, run through a trouble shooting script that may not apply, "reboot your computer" -- my Slackware web server? No! My PC? No! The concept of accessing the Internet via a firewall box and bridging the modem into stupid mode doesn't occur to them. Really fun complaint didn't get resolved until a couple of us users teamed up to provide the same technical info from our websites, which could not be viewed by anyone on the cidr/16 block the ISPs customers were on. Incoming port 80 disabled from their /16 block was so hard to explain, took two of us a week to get it through dodo's corporate head. Dodo advertises "Dodo, for Internet that flies" So I put up "dodo, for Internet that dies" top of my web pages -- that got up management's nose? Dunno, eventually they fixed the faulty border router, they had two tech savvy customers locate the thing for them (tcptraceroute) run from an outside server. It's wonderful how I digress from charging a pair of 6V batteries on a 12V charger, yes, you can put a pair or more LA batteries in a series string, onto the same charger. You can even charge LA batteries in parallel, it is better for new batteries than charging them in series. not so easy in equipment, and not enough benefit to do a switching circuit. Though I did that for a pair of 100AH batteries, which was fine until I miswired a dual battery connector, plugged it in, heard that lovely DC high current hiss before the 35A battery fuses blew, lost an Anderson connector, welded mated!
> >(...) > >>> Then you get to figure out a battery supply for >>> your wireless connection point and your ADSL modem. >> >> Wired connection (Ethernet) and I have a 12VDC modem :) > >Next: Battery and charger circuit!
Little stuff, hang a float charger off the same 19V DC supply to a laptop? Yes, I know float charging can cause corrosion, it's the race between corrosion (over- charge) and sulphation (undercharge) that kills standby SLA batteries. Hmm, water loss shouldn't be an issue for SLAs in standby service. They're supposed to have some recombinant methods built in to address that.
> >>>> I still like the idea of lighting up brightly when power >>>> goes off, not that it happens here very often, but maybe >>>> I pickup some cheap solar panels one day, from >>>> disillusioned users when govt subsidies dry up? > >Have a team available to do the salvage and cleanup!
If it happens there's lots from the bush blocks wanting the things ;)
> >A local community college has installed US$11.3 million >worth of photovoltaics, covering parking areas. >They are at 37 degrees latitude. The panels are not >angled toward the sun, but face straight up! >http://www.mercurynews.com/sunnyvale/ci_19453056
Silly, you're supposed to put them up at closer to the winter angle for maximum performance year round. Wisdom around here on the bush blocks is that tracking the sun is not worth the complexity, put in an extra fixed panel. Google Earth tells me I'm at 36&#2013266106;45' (South). Maybe they figured the loss of efficiency plus increase of flat facing panels dust collection made some sense? The Cat in the Hat solution?
> > >http://tiny.cc/2q1t1 or: ><http://extras.mnginteractive.com/live/media/site568/2011/1201/20111201__scup1202solar~1_GALLERY.JPG> > >This picture looks straight south. there isn't even a way >to point the panels normal to the sun!
Google Earth has it as of June 20, 2011, 'Fly to' "De Anza College Solar Panel Project" and zoom in, hard to miss.
> >An architectural triumph, perhaps.
Yes, shade between the panels moves with the sun, keeping the cars cooked evenly? From the Google Earth image, looks like it's on top of a building?
> >An efficiency nightmare, definitely.
Yes, perhaps they want the dust to settle and reduce the heat loading. Or maybe it'll blow off like the Mars Rovers?
> >(...) > >> I speak only for the crazy case of a temporary crash on >> used solar panel prices as people discard ever realising >> the vague promise of some RoI in their lifetimes :) > >I think a manufacturer would be more likely to >warehouse or destroy panels rather than sell >them for half the cost of manufacture.
And retarget the panels for low voltage use. Things wired to supply several hundred volts for direct conversion to our 230VAC mains. Who wants to run a 100 or 120 cell battery bank? Even the phone companies chose 24 cell (48V) as highest spanner burning current but lowest direct lethality, easily a tingle. So we got any old house[1] with these things bolted on, high voltage special DC connectors -- I was stunned into disbelief when I saw what they doing for economy. Corrosion, summer heat, winters below freezing overnight, okay we don't get snow, but lots of dew in the mornings for half of the year. Lower voltage, standby battery option and a boost converter would add not much to the cost for safer panel installation. [1] Weatherboard construction with a tin (well painted, rusty galvanised iron) roof I saw within walking distance of here. Then there's critters like possums and birds nesting may do some damage, or rats nibbling on the HVDC cables in the roof space They not last? Grant.
> >--Winston