Here is the graph straight from the charge monitor for our solar panels, to give you an idea what the charging pattern looks like. This is for a pair of 60w panels.
http://www.thelar.com/gallery2/v/Wireless/Hogback/graph_image1.png.html Matt Larsen vistabeam.com Christopher Erickson wrote: > First, the Sun never shines 24 hours in a day unless you are above > the Arctic circle. And even then, that only happens for a few days > of the year. > > Second, there isn't much charging going on when the Sun is near the > horizon, which is most of the time when in Northern latitudes. > > For example, an 80 watt panel will NEVER output 80 watts in Anchorage, > Alaska because even at solar noon in the summer, the Sun is only > around 60 degrees up in the sky. And below about 25 degrees, there > isn't any charging going on at all. > > So anyway think of an amperage sine wave that builds up in the morning, > peaks at solar noon and then diminishes in the afternoon. > > The math is more complicated than it first appears. > > "My advice is always free and worth every penny!" > > -Christopher Erickson > Network Design Engineer > 5432 E. Northern Lights Blvd., Suite 529 > Anchorage, AK 99508 > > > > >> -----Original Message----- >> From: wireless-boun...@wispa.org [mailto:wireless-boun...@wispa.org]on >> Behalf Of Mike >> Sent: Wednesday, August 26, 2009 9:06 PM >> To: WISPA General List >> Subject: Re: [WISPA] solar site >> >> >> I'm not sure I buy into your math. If I have a repeater site that is >> pulling 1A @ 12V, then it is consuming something like 12W, right? If >> I have 60W of solar panel (2 toys) then when conditions are optimal, >> I have 48W left over to charge the battery. >> >> Lets say I am REALLY north, and the panels are only producing 45W. I >> still am consuming 12W with the radios, and have 33W left over to >> charge the battery. If I have an 800AH battery 24 Hours of sun will >> run the radios AND fully charge the battery. If the sun shines 24 >> hours out of 33.3 days, I will stay ahead of the curve and the >> battery will stay charged. >> >> No sun for 33.3 days and my 800AH battery will finally die. I NEVER >> see those conditions here in the midwest. I'll still maintain you >> can do a repeater site for $500 in solar power costs and if you >> monitor battery condition it will work just fine. >> >> At 09:54 PM 8/26/2009, you wrote: >> >>> Here in the north, I wouldn't bother with anything less than 100w of >>> panel. >>> >> >> >> ---------------------------------------------------------------------- >> ---------- >> WISPA Wants You! Join today! >> http://signup.wispa.org/ >> ---------------------------------------------------------------------- >> ---------- >> >> WISPA Wireless List: wireless@wispa.org >> >> Subscribe/Unsubscribe: >> http://lists.wispa.org/mailman/listinfo/wireless >> >> Archives: http://lists.wispa.org/pipermail/wireless/ >> > > > -------------------------------------------------------------------------------- > WISPA Wants You! Join today! > http://signup.wispa.org/ > -------------------------------------------------------------------------------- > > WISPA Wireless List: wireless@wispa.org > > Subscribe/Unsubscribe: > http://lists.wispa.org/mailman/listinfo/wireless > > Archives: http://lists.wispa.org/pipermail/wireless/ > > -------------------------------------------------------------------------------- WISPA Wants You! Join today! http://signup.wispa.org/ -------------------------------------------------------------------------------- WISPA Wireless List: wireless@wispa.org Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/
