Somewhat OT: Long term design
in [Design]
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From: Sylvia Else on 16 Jan 2010 00:07 Robert Baer wrote: > Sylvia Else wrote: >> Jan Panteltje wrote: >>> On a sunny day (Thu, 14 Jan 2010 17:54:31 -0500) it happened WangoTango >>> <Asgard24(a)mindspring.com> wrote in >>> <MPG.25b96ab48fc5c5b698ae28(a)news.east.earthlink.net>: >>> >>>> In article <035f8778$0$1309$c3e8da3(a)news.astraweb.com>, >>>> adrian(a)qq.vv.net says... >>>>> Maybe you could ask how far in the future you have to go before >>>>> your 'device' becomes unrecognisable ? >>>> What are you talking about? >>>> I've watched TV and not only do those guys instantly recognize >>>> millennium old devices, they recognize millennium old ALIEN devices, >>>> and they all invariably function. I would be more interested in a >>>> power source that could just sit for that period of time and still >>>> be useable, >>> >>> >>> Solar. >> >> The sun is unliklely to disappear over these sorts of timescales. >> >> But will the solar cell even still be exposed to it? We usually have >> to dig down into the ground to find prehistoric sites, even from a few >> thousand years ago. >> >> And if the cell manages to remain exposed - how many severe hailstorms >> do you get an a period of several thousand years? Even if you choose a >> place that's currently unlikely to get hailstorms, will that remain >> true for the next thousands of years? >> >> Sylvia. > Noting wrong using a solar cell using your condition that the device > "be secreted from human tampering" for that 1000 years. If it's hidden away, and only exposed to the sun after the time is up, then we need a mechanism to do the exposing, and that mechanism will require a power source. Sylvia.
From: Sylvia Else on 16 Jan 2010 00:13 John Larkin wrote: > On Fri, 15 Jan 2010 11:19:34 -0500, WangoTango > <Asgard24(a)mindspring.com> wrote: > >> In article <hio9k9$fsu$1(a)news.albasani.net>, pNaonStpealmtje(a)yahoo.com >> says... >>> On a sunny day (Thu, 14 Jan 2010 17:54:31 -0500) it happened WangoTango >>> <Asgard24(a)mindspring.com> wrote in >>> <MPG.25b96ab48fc5c5b698ae28(a)news.east.earthlink.net>: >>> >>>> In article <035f8778$0$1309$c3e8da3(a)news.astraweb.com>, adrian(a)qq.vv.net >>>> says... >>>>> Maybe you could ask how far in the future you have to go before your >>>>> 'device' becomes unrecognisable ? >>>> What are you talking about? >>>> I've watched TV and not only do those guys instantly recognize >>>> millennium old devices, they recognize millennium old ALIEN devices, and >>>> they all invariably function. I would be more interested in a power >>>> source that could just sit for that period of time and still be useable, >>> >>> Solar. >>> >> Really....do we know what a solar cell will do after 1000yrs of sitting? > > Good cells are fairly klunky monocrystalline silicon PN junctions. > They'd probably work fairly well after a million years if stored > properly. > This is where I wonder about difusion. Will those doping atoms stay put over those sorts of time scales, or would we end up with a piece of silicon pretty much equally doped throughout with both doping materials? Sylvia.
From: Robert Baer on 16 Jan 2010 03:29 Sylvia Else wrote: > Robert Baer wrote: >> Sylvia Else wrote: >>> Jan Panteltje wrote: >>>> On a sunny day (Thu, 14 Jan 2010 17:54:31 -0500) it happened WangoTango >>>> <Asgard24(a)mindspring.com> wrote in >>>> <MPG.25b96ab48fc5c5b698ae28(a)news.east.earthlink.net>: >>>> >>>>> In article <035f8778$0$1309$c3e8da3(a)news.astraweb.com>, >>>>> adrian(a)qq.vv.net says... >>>>>> Maybe you could ask how far in the future you have to go before >>>>>> your 'device' becomes unrecognisable ? >>>>> What are you talking about? >>>>> I've watched TV and not only do those guys instantly recognize >>>>> millennium old devices, they recognize millennium old ALIEN >>>>> devices, and they all invariably function. I would be more >>>>> interested in a power source that could just sit for that period of >>>>> time and still be useable, >>>> >>>> >>>> Solar. >>> >>> The sun is unliklely to disappear over these sorts of timescales. >>> >>> But will the solar cell even still be exposed to it? We usually have >>> to dig down into the ground to find prehistoric sites, even from a >>> few thousand years ago. >>> >>> And if the cell manages to remain exposed - how many severe >>> hailstorms do you get an a period of several thousand years? Even if >>> you choose a place that's currently unlikely to get hailstorms, will >>> that remain true for the next thousands of years? >>> >>> Sylvia. >> Noting wrong using a solar cell using your condition that the device >> "be secreted from human tampering" for that 1000 years. > > If it's hidden away, and only exposed to the sun after the time is up, > then we need a mechanism to do the exposing, and that mechanism will > require a power source. > > Sylvia. Sine i am a baer, may i growl and say "Gurr-avity"?
From: Robert Baer on 16 Jan 2010 03:33 Sylvia Else wrote: > John Larkin wrote: >> On Fri, 15 Jan 2010 11:19:34 -0500, WangoTango >> <Asgard24(a)mindspring.com> wrote: >> >>> In article <hio9k9$fsu$1(a)news.albasani.net>, >>> pNaonStpealmtje(a)yahoo.com says... >>>> On a sunny day (Thu, 14 Jan 2010 17:54:31 -0500) it happened WangoTango >>>> <Asgard24(a)mindspring.com> wrote in >>>> <MPG.25b96ab48fc5c5b698ae28(a)news.east.earthlink.net>: >>>> >>>>> In article <035f8778$0$1309$c3e8da3(a)news.astraweb.com>, >>>>> adrian(a)qq.vv.net says... >>>>>> Maybe you could ask how far in the future you have to go before >>>>>> your 'device' becomes unrecognisable ? >>>>> What are you talking about? >>>>> I've watched TV and not only do those guys instantly recognize >>>>> millennium old devices, they recognize millennium old ALIEN >>>>> devices, and they all invariably function. I would be more >>>>> interested in a power source that could just sit for that period of >>>>> time and still be useable, >>>> >>>> Solar. >>>> >>> Really....do we know what a solar cell will do after 1000yrs of sitting? >> >> Good cells are fairly klunky monocrystalline silicon PN junctions. >> They'd probably work fairly well after a million years if stored >> properly. >> > > This is where I wonder about difusion. Will those doping atoms stay put > over those sorts of time scales, or would we end up with a piece of > silicon pretty much equally doped throughout with both doping materials? > > Sylvia. CK722s were made with relatively impure chemicals and processed WRT what is available today, and i suspect the base junctions were not all that swift - but there are some CK722s that have reasonable characteristics today. Tough to extend that "decay" to silicon solar cells, but may give a crude guesstimate as to worst case expectations..
From: Sylvia Else on 16 Jan 2010 03:36
Robert Baer wrote: > Sylvia Else wrote: >> Robert Baer wrote: >>> Sylvia Else wrote: >>>> Jan Panteltje wrote: >>>>> On a sunny day (Thu, 14 Jan 2010 17:54:31 -0500) it happened >>>>> WangoTango >>>>> <Asgard24(a)mindspring.com> wrote in >>>>> <MPG.25b96ab48fc5c5b698ae28(a)news.east.earthlink.net>: >>>>> >>>>>> In article <035f8778$0$1309$c3e8da3(a)news.astraweb.com>, >>>>>> adrian(a)qq.vv.net says... >>>>>>> Maybe you could ask how far in the future you have to go before >>>>>>> your 'device' becomes unrecognisable ? >>>>>> What are you talking about? >>>>>> I've watched TV and not only do those guys instantly recognize >>>>>> millennium old devices, they recognize millennium old ALIEN >>>>>> devices, and they all invariably function. I would be more >>>>>> interested in a power source that could just sit for that period >>>>>> of time and still be useable, >>>>> >>>>> >>>>> Solar. >>>> >>>> The sun is unliklely to disappear over these sorts of timescales. >>>> >>>> But will the solar cell even still be exposed to it? We usually have >>>> to dig down into the ground to find prehistoric sites, even from a >>>> few thousand years ago. >>>> >>>> And if the cell manages to remain exposed - how many severe >>>> hailstorms do you get an a period of several thousand years? Even if >>>> you choose a place that's currently unlikely to get hailstorms, will >>>> that remain true for the next thousands of years? >>>> >>>> Sylvia. >>> Noting wrong using a solar cell using your condition that the >>> device "be secreted from human tampering" for that 1000 years. >> >> If it's hidden away, and only exposed to the sun after the time is up, >> then we need a mechanism to do the exposing, and that mechanism will >> require a power source. >> >> Sylvia. > Sine i am a baer, may i growl and say "Gurr-avity"? Back to needing a mechanical mechanism that will work. Sylvia. |