A Geek Goes Flying

So, I picked up a Storm 2 battery pack , for the capacity, the screen showing charging / discharge details, and because it can be charged via a DC port. I figured it would be a good companion for the Renogy E.Flex 50 solar panel. The panel puts out 21.6V and 3.04A to an open circuit, and has a nominal output of 18V at 2.77A (49.86W). In reality , of course, I usually see the panel top out in the low 30W range, almost always around 17V with the available current dictating the watts transmitted: 17.23V 1.76A 30.3W (12/15 9:25 a.m. direct sun) 13.96V 0.03A 00.4W (12/14 12:13 p.m. shade) 17.12V 1.00A 17.1W (12/14 10:11 a.m. direct sun) 12.12V 1.02A 17.4W (12/17 10:45 a.m. thin cirrus cloud cover) 17.06V 0.62A 10.5W (12/17 10:01 a.m. thin cirrus cloud cover) Into a full battery pack, I was seeing higher voltages but minimal current, with correspondingly reduced wattage, e.g.: 1 9.51V 0.04A 00.7W (12/20 9:52 a.m. direct sun). This should work with the Storm 2 pack, which purportedly...

A week into my wildly unscientific solar power experiment, I’ve come to mistrust all capability / capacity specifications.     Solar panels. I was told to expect about 1/2 the rated power from even the highest quality solar panels. I’m getting a bit better than that (I’m seeing the 50W Renogy top out around 32W in direct, morning, SoCal winter sunshine). Battery pack: Capacity. Just like with “normal” portable battery packs, the capacities are overstated vis-a-vis what you can actually expect them to provide in the real world. One reviewer, with instrumentation far in excess of what I have access to, observes 92% of advertised capacity is par for the course. ( https://www.californiaskys.com/blog/ebl-voyager-1000-review ) Battery pack: Efficiency.  Renogy states in its manual for the battery pack “The charging conversion rate of this power bank is around 80%-90% (the 10%-20% conversion loss is due to the heat generation when power is transferred in batteries and charging ...

Renogy power bank connected to MacBook Air It looks like the Renology R50EF E.FLEX 50 portable solar panel, and maybe also the RPB-72000PD 72,000 mAh / 266 Wh portable power bank, might be discontinued, so I grabbed ‘em while I could. The power bank comes with a Lyangel LY005SPS-200200U 40W (20V 2A) wall wort (5.5x2.1mm DC, positive pin negative shield). I used that to charge the bank to full (it arrived with a ~50% charge). So far I’ve tested wireless charging with an iPhone 12 Pro (works) and now through the Klein meter I have USB-C PD (1) connected to a MacBook Air and it’s supplying 19.73V 1.89A (36.7W). (The Mac sees it as a 60W charger.) The power bank is a beast, about the size and heft of a dense hardback book. It comes with that AC adapter, a ~19" DC to DC cord (5.5x2.1mm (“DC5521”) male connectors on both ends, about 10mm long), a set of (8) adapter tips (5.5x2.1mm female, and 8 various male ends), a soft case with a pouch for accessories, and a manual . It charges via t...