<div dir="ltr"><div class="gmail_extra"><br><div class="gmail_quote">On Fri, Jun 20, 2014 at 7:09 AM, Ben Burrell <span dir="ltr"><<a href="mailto:baburrell@gmail.com" target="_blank">baburrell@gmail.com</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div dir="ltr">George:<div>I have a physics student who will be assembling and testing a solar setup similar to that described on the Unleash Kids site (<a href="http://www.unleashkids.org/2014/02/21/off-the-grid-suitcase-solar-solutions-for-power-in-haiti/" target="_blank">http://www.unleashkids.org/2014/02/21/off-the-grid-suitcase-solar-solutions-for-power-in-haiti/</a>). I understand that the system can re-charge about 10 xo1's each day with 6 hrs of sunlight where the battery is discharged no more than 50% (one of the things she'll test). </div>
<div>Can you give me some estimates about what is needed to power the NUC you're testing, a hard drive with iiab, and an access point?</div></div></blockquote><div><br></div><div>The average NUC power is about 9 watts, and the AP that I have running from village telco draws 1.5 watt (and runs on 9-15 volts -- good for lead acid batteries). I don't think village telco units are easily available from amazon. Maybe someone else knows. </div>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div dir="ltr"><div>1. Approx what # of watts per hour do the panel(s) need to generate to run the system for, say, 3 hours per day...assuming 6 hours of sunlight and maintaining a proper discharge of the battery.</div>
</div></blockquote><div>Well, if you need 300 whr for 10 XO's, and 30jwhr to run the NUC for 3 hours, the bar minimum is 330 watt hours per day. Then you need to factor in losses in charging of battery, overcast days, etc. So if you had a 100w solar panel working for 6 hours per day, with clouds, overhanging trees, lack of proper sun orientation, you'd probably be lucky to get 330 watt hours per day</div>
<div> </div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div dir="ltr">
<div>2. Is the 10 amp charge controller (described on the website) sufficient or would a 20 amp be better?</div></div></blockquote><div><br></div><div>depends a lot on the size of your solar panel. In my fixed single 100 watt solar installation, I've never seen more than 65 watts (5Amp). </div>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div dir="ltr"><div>3. Is more than one 12V battery needed?</div></div></blockquote><div>batteries come in different capacities. If you want to handle a few cloudy days the trojay 105 AHR 12v battery should really only be used to store 600 watthours (use half). With losses, that's not really enough for 2 days overcast. So probably two 6 volt trojan t-105's, which are rated at 225AHr, might be a better choice</div>
<div> </div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div dir="ltr"><div>4. Can you power an access point from DC (please pardon my ignorance) If not, is there a low cost true sine wave inverter that you can recommend?</div>
</div></blockquote><div><br></div><div>It's worth your time to find a 12 powered AP I think. I've been impressed with the support we can get for village telco units.</div><div> </div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
<div dir="ltr">
<div>Thanks.</div><span class="HOEnZb"><font color="#888888"><div>Ben</div></font></span></div><div class="gmail_extra"><br><br><div class="gmail_quote"><div><div class="h5">On Fri, Jun 20, 2014 at 6:10 AM, George Hunt <span dir="ltr"><<a href="mailto:georgejhunt@gmail.com" target="_blank">georgejhunt@gmail.com</a>></span> wrote:<br>
</div></div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div><div class="h5"><div dir="ltr">Tony,<div><br></div><div>I'm currently running the i3 NUC off of a solar charged LA battery. Boots fine. Per Richard Smith's analysis, I'd say that the NUC can handle the 14+ charging/equalizing cycles, but might not get a full 12v in really cold climates (with the internal 2.5 hard disk running on the 5 volt rail, and the motherboard probably using buck converters to much less than 12, I'd expect it to work well).<br>
<div><br></div></div></div><div class="gmail_extra"><br><br><div class="gmail_quote">On Fri, Jun 20, 2014 at 12:42 AM, Tony Anderson <span dir="ltr"><<a href="mailto:tony_anderson@usa.net" target="_blank">tony_anderson@usa.net</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">George,<br>
<br>
Great news! It sounds like this may turn into the hardware of choice for a school server in the coming<br>
year. I'll try to see how to get one in EU - may have to wait until I get back to Germany in a few weeks.<br>
<br>
If possible, could you verify that it boots and operates from a 12v battery? This is the environment in the Kokobe school in Lesotho. I would like to swap out the MSI and operate a server directly from the battery.<span><font color="#888888"><br>
<br>
Tony</font></span><div><div><br>
<br>
On 06/20/2014 01:54 AM, George Hunt wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
the i3 NUC arrived, has an upgraded bios, and is running the hard drive that I removed from the MSI, successfully headless. The annoying thing is that they changed the video output to micro hdmi. Fortunately I had an adapter.<br>
<br>
the Documentation is specific that it will run on 12-19. I was concerned that lead acid batteries might go lower than that during deep discharge, but referring to the charts suggests that at capacity in amp hours divided by 20 gets down to 12 volts at 30% remaining charge. Docs at <a href="http://downloadmirror.intel.com/23089/eng/D54250WYB_D34010WYB_TechProdSpec05.pdf" target="_blank">http://downloadmirror.intel.<u></u>com/23089/eng/D54250WYB_<u></u>D34010WYB_TechProdSpec05.pdf</a><br>
<br>
The NUC idles at 8 watts, spiking to 16 when it's doing anything intense.<br>
</blockquote>
<br>
</div></div></blockquote></div><br></div></div></div><div><div><div class="">
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