Wow.. I find that extremely interesting
Id LOVE to find a way (or rather spend the time finding the right way) to do this at my house. My electrical bill at my house is typically around $400/month. The challenge is that even at $4800/year or $48k over 10 years lets say for simple math Im not really sure there is anything in that price range that could provide for the power I need to be completely off grid (and sustain for 24-48 hours of limited daylight). Am I totally wrong on this? Thanks, Paul From: Af [mailto:af-boun...@afmug.com] On Behalf Of Bill Prince Sent: Friday, September 11, 2015 1:01 PM To: af@afmug.com Subject: Re: [AFMUG] a new one, I think... According to a friend of mine "Anything can be built." We have several solar sites, and when they have enough battery and panels, they are every bit as reliable as utility power. In fact, one site we have had installed for 4 years without a single power issue. Our older sites have had some relatively minor issues, as we learned how to do it. But first, I would guess that your power requirements are closer to 90 or 100 watts just doing a rough mental calculation. Take the number of watts you really need (say 100 watts in your case). You need that 24 hours a day, so multiply that by 24 for 2,400 watt-hours per day. Multiply that by 10 (now 24,000 watt-hours). That's how much "battery" you need. Because batteries are rated on 100% discharge, you then need to double that amount (now at 48,000 watt-hours). Size your batteries according to that. You want ~~ 48,000 watt-hours of battery (close to 4,000 amp-hours if using 12 volt batteries). Then decide on how many watts you can get out of your solar panels on the worst day (generally December 21). You want your panels capable of fully recharging the batteries in about 1/2 of the solar time you have on that worst day. Where we are south of San Francisco, we get about 5 good hours on December 21 (37th parallel). You're at the 27th parallel, so you probably get another hour or so. Just one more anecdote, we have numerous neighbors that live "off the grid". When the big storms hit, they are usually the only ones that still have power. bp <part15sbs{at}gmail{dot}com> On 9/10/2015 6:00 PM, Paul McCall wrote: OK, so I am working with a grounding expert today, getting some opinions on a couple difficult towers, and one of the first suggestions he has for me as I mention that I am looking to do fiber / DC up this tower is� �Have you considered going solar up the tower?�� (to eliminate power surges completely from going up the tower) � Hmmmm� � So my brain starts wrestling with that��� Is it practical?�� � Say on a tower with a Netonix DC powered switch running at 48v or 24v, powering �6 ePMP APs �and 2 �320APs, 2 Mikrotik Bhs, and a small Mikortik router.� � Would be about 50 watts maximum according to my quick calcs.� � Not knowing anything about solar, has battery technology developed enough that it would be practical (size wise) to have enough batteries and a charge controller up in a box on a tower?� And what size solar panel would I need to drive that? � Paul
