Subj : Solar TV Battery Test To : Nancy Backus From : Barry Martin Date : Fri Feb 07 2020 08:57:00 Hi Nancy! BM> Finally semi-tested the recharging of a 12v UPS battery using a solar BM> cell charger. -- Overall the run a TV off a 12v battery when the BM> power fails project. BM> In a word: failed. Also have to add there are a lot of known details BM> working against. The project could work, just not here conveniently. NB> Well, at least now you know... :) True. LIS later in that reply or in an interim message the only window here without the UV Block that gets Sun is the one in the basement. Now can get to it (clean-up project coming along!), workbench a bit crowded -- will hold off a little longer as no big rush and keep things focused. Even if the power failed right now there are three batteries available which should run over three hours each. Not planning on keeping that many charged: one is the battery from the UPS that failed because the second battery was bad. Second is from a UPS right now is a spare (not for too much longer!), and the third was a spare/replacement battery. BM> Using an inexpensive 1.5 Watt solar battery charger; different one BM> from the one in the basement window (will go down and continue that BM> clean up project later). Temporarily mounted it to the south-facing BM> window up here in the Computer Room. A bit hazy out, but otherwise BM> bright. Sun being filtered a bit through leafless tree branches. BM> Measured ~4 volts -- we want 12 v! And the manual says up to 24 volts! BM> (I can build something to regulate down; technically I can up-convert BM> too but there's other losses.) BM> Later the Sun moved and essentially unobstructed: 7 v at noon. Still BM> insufficient. BM> Several problems with the test setup: BM> -- The window has 'UV Block'. So do all the other windows in the BM> house except for the ones in the basement. NB> That will do it... all on its own... means that the solar NB> charging isn't going to get through... Richard had a similar NB> problem with using a security camera at church... the UV and IR NB> blocks on the newer windows are useful for some things, but not NB> for cameras in the IR range and charging from the UV range.... :) For every action there is an opposite reaction! ...Could set up outside -- temporary would probably be dealing with freezing conditions and burst batteries. Running wires to inside -- has possibilities. BM> -- Going through a window screen. Keeps bugs out but doubt does that BM> much to sunshine. Using this position because there's a screw BM> hole at the window frame from the window air conditioner's side BM> flaps: used a wire clamp to keep the solar panel in position. (Did BM> test later: moved to the top window: glass only, no screen. Got BM> less voltage [!] but also the Sun had moved.) NB> I wouldn't think that the screen would have much effect... Nor I but figured worth the experimental time. BM> Didn't try outside: warm enough today but in winter quite possible BM> well below freezing, could freeze and therefore break the battery. BM> Solar cell outside, run wires to inside.... Thinking this is more of a BM> now-emergency than something planned and semi-permanent. NB> And might be that you'd do better to test that aspect come later NB> spring through summer and early fall.... In warmer weather, you NB> could try doing it just through the screen... I'd think that NB> you'd also need to protect it from the elements... Hmmm: now that's a possibility! Thanks! At this point not sure if the solar charger is sufficiently weather resistant to stay outside permanently.... BM> So appears the throw-it-together solar charging isn't going to work BM> here. Do want to state I think solar works, just needs to be outside BM> and properly aligned. The manual for this little portable critter BM> even says may need to realign 10ø. Will discontinue the solar charger BM> option; will have to semi-plan ahead and maintain a battery or two to BM> be charged a different way, right now electricity. NB> For now, it's good you have other options... ;) And now re-open later for the between the screen and window consideration. May end up simply maintaining a battery on electricity -- the battery I snagged from the UPS (the other battery had failed) also appears to be slightly damaged (or maybe just because older) and doesn't seem to hold a charge quite as well as the other two batteries. Does hold a charge for at least a couple of weeks.... BM> ... Useless Invention: Solar powered night light. NB> Not necessarily useless... if it can store up enough during the NB> day when the sun is shining, it could last the night as a night NB> light... ;) After all, that's what those solar lights that one NB> puts along the sidewalk or driveway do... soak in the power NB> during the day, and when it gets dark, shine the lights.... Right: when working I had in my pocket a small flashlight where the coin cell battery inside was recharged by a small solar panel. That also barely recharged through the window because of the UV Block. I had purchased three or four -- inexpensive and gave one or two away. Still have two: theoretically alike but one somewhat charges inside (dim) and the other not at all. Outside both charge to full brightness. ¯ ® ¯ Barry_Martin_3@ ® ¯ @Q.COM ® ¯ ® .... Geriatric Party Games! Sag, You're It --- MultiMail/Win32 v0.47 þ wcECHO 4.2 ÷ ILink: The Safe BBS þ Bettendorf, IA --- QScan/PCB v1.20a / 01-0462 * Origin: ILink: CFBBS | cfbbs.no-ip.com | 856-933-7096 (454:1/1) .