00:17 <Oksana> kodomo_: I guess hope is here, but attracting more pre-orders (especially not-PayPal ones) would help. http://neo900.org/news/paypal-trouble-delays-project Also, if there is a way to force PayPal to release the money ( PayPal-customers telling PayPal that they are fully aware of risks and not going to chargeback; or some authority finding PayPal's requests for Neo900's operations too...

00:17 <Oksana> ...intrusive), it would be great.

00:32 <Oksana> Hmm, what about this one? Clear thin layer of crystal glass for solar power (a tad tricky to fit as modification to existing case)? Smartphone camera receiving signals (would only back-camera work for it, or would front-camera work, too?)? Would camera LEDs (two white and one red) be able to transmit signals? Software-wise, how difficult would it be to pull it off, would it require a...

00:32 <Oksana> ...dedicated chip for LiFi? Hardware wise, do cameras and LEDs have the speeds required?

00:32 <Oksana> https://en.wikipedia.org/wiki/Li-Fi

00:39 <Oksana> How is Euro going? /It may be important for your final Neo900 price, correct? / http://neo900.org/estimate Not moving much... http://fx.sauder.ubc.ca/cgi/fxplot?b=EUR&c=USD&rd=731&ld=31&lm=1&ly=2016

01:17 <wpwrak> (li-fi) hmm, tricky. the flash controller is attached via i2c. but maybe one could modulate a fast signal via strobe (gpio). also, i'd be surprised if you could tweak the camera to operate at kfps speeds. (though i don't know if it's outright impossible)

01:19 <wpwrak> (euro) with today's exchange rate, we "lost" some 3% since may 2015. in general, the rate has been bouncing between +3% to -6%.

01:19 <wpwrak> see also http://fx.sauder.ubc.ca/cgi/fxplot?b=EUR&c=USD&rd=*&fd=1&fm=5&fy=2015&ld=31&lm=12&ly=2016&y=daily&q=volume&f=svg&a=lin&m=0&x=indx

01:19 <wpwrak> >100% is bad news, <100% is good news

01:20 <wpwrak> so, unpleasant but nothing devastating on that front

01:22 <wpwrak> (solar) i think you need a 3D printer, to make a replacement bottom cover ;-)

01:23 <DocScrutinizer05> thanks! re photovoltaic, the theoretical maximum available for energy harvesting from sunlight is ~1000W per square meter. Breaking that down to the size of a PV cell that would fit on N900 case results in the conclusion that it's absolutely not worth it

01:26 <DocScrutinizer05> with a estimated efficiency of 10% for the average PV amorphous Si PV cell, you could get a *maximum* of 500mW

01:26 <wpwrak> about 1 W. and probably not so nice side-effects if the neo900 is left in intense sunlight for the whole day.

01:26 <DocScrutinizer05> that too

01:26 <wpwrak> https://en.wikipedia.org/wiki/Solar_cell_efficiency#/media/File:PVeff(rev160111).jpg is more optimistic :)

01:27 <Wizzup> You could also just get some usb solar charger and connect that to the usb

01:27 <Wizzup> (to the usb of the neo900)

01:27 <DocScrutinizer05> yep

01:28 <wpwrak> Wizzup: there we have something that's a lot more reasonable. let the solar charger cook in the sunlight while the neo900 rests in the shadow

01:28 <Wizzup> yep

01:28 <Wizzup> for me it is pointless, since the netherlands doesn't get sun :)

01:29 <wpwrak> i guess Oksana is thinking of long trips into the Australian desert :)

01:31 <DocScrutinizer05> even then it's mostly pointless to try and keep alive a phone with a 5*10cm solar cell which even theoretically can't get exposed to sunlight more than 50% of time

01:32 <Wizzup> when it's a usb one, you can make it much larger and attach it to a backpack :)

01:32 <DocScrutinizer05> unless you plan to rest at daytime and move only during nighttime, it's even way less or way poorer efficacy

01:32 <Wizzup> bagpack* ;)

01:33 <DocScrutinizer05> there are backpacks with integrated PV cells

01:33 <DocScrutinizer05> commercially available

01:33 <Wizzup> exactly

01:35 <DocScrutinizer05> economic break even is at around 10 years of operation here in Germany which has special high non market driven prices for solar energy

01:36 <Wizzup> that is - if they last that long

01:36 <Wizzup> of course, it's not just about economic break even :)

01:37 <DocScrutinizer05> here it's almost economically feasible to make money from buying cheap regular electricity for lamps to operate your PV and sell the expensive "solar" electricity

01:38 <DocScrutinizer05> ;-)

01:38 <wpwrak> buy regular, feed into fake array, sell relabeled "solar" ? :)

01:38 <DocScrutinizer05> the inverse of the infamous solar powered flashlight

01:38 <DocScrutinizer05> wpwrak: this works

01:39 <DocScrutinizer05> money from nothing

01:41 <DocScrutinizer05> I guess a cheap rarely used way to improve efficiency resp TCO ratio of PV would be to use mirrors to amplify / multiply the amount of light on a PV panel

01:42 <DocScrutinizer05> regular PV Si cels should be able to cope with at least twice to 3 times the maximum solar energy per area

01:43 <wpwrak> i wouldn't be surprised if they malfunctioned if you suddenly had a lot more light than peak sun output :)

01:43 <DocScrutinizer05> nah

01:44 <DocScrutinizer05> actually on spacelab etc the use lenses to 'bake' PV cells punctually to regenerate them and 'cook out' some negative effects from cosmic wind or whatever

01:45 <wpwrak> yes, but they're designed for that :)

01:45 <DocScrutinizer05> the only think you need to take care about is temperature

01:45 <DocScrutinizer05> thing*

01:45 <wpwrak> i mean, you have the whole system, not just the PV element

01:46 <DocScrutinizer05> using IR-transmissive mirrors would greatly reduce any problem with temperature arising from focusing mirrors. Active cooling can do the rest and even serve as second purpose means to harvest heat for hot water etc

01:48 <DocScrutinizer05> plus >90% of time, you don't nearly have the max solar power. In that situation multiplying the low light to reach nominal maximum will go a long way without *any* worries about side effects

01:51 <DocScrutinizer05> a normal PV cell should withstand a 100°C easily I guess. So a sort of water 'cooling' could 'passively' (without external power or active elements like electronics etc) move the mirrors to defocus them as soon as the water starts boiling and thus builds up vapor pressure

01:53 <wpwrak> seems that you want 25 C: http://www.solar-facts-and-advice.com/solar-panel-temperature.html

01:55 <DocScrutinizer05> >>In some cases the heat factor can reduce your output by 10% to 25% depending on your specific location.<< not exactly negligible but not too bad either

01:56 <wpwrak> yes, but that's without artificially boosting it, as you propose

01:56 <DocScrutinizer05> but yeah, 100°C is maybe too hot

01:57 <DocScrutinizer05> anyway the usual case is you don't even have 100% of solar energy and you want to boost it to just reach the projected maximum nominal power

02:36 <DocScrutinizer05> are the usual commercially available PV panels equipped with a IR reflective coating?