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Solar Panel help

  1. Nov 6, 2015 #1
    hi i wonder be able to help me i got a 150w solar panel , and a 20a charge controller and two marine 110Ah Leisure Batteries, 12V, i want to run the dvr box which is using around 12v 5a i want it to be on 24/7 do i have enough battery power to last that long ? also it be running off a 12v jack to the dvr box it self from the charge controller ?
    also i have got a 2000w (4000W peak) power inverter 2000 watt 12v UPS inverter battery charger for backup and using tools now and again
  2. jcsd
  3. Nov 6, 2015 #2


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    Staff: Mentor

    Welcome to PF!

    If the dvr is really pulling 5 amps, then no, you don't have enough power for it. Solar panels average 15-20% usage factor and obviously that is highly weather and season dependent. But if 5 amps is what the dvr nameplate says, it may not actually be pulling that much continuously. You may want to measure it.
  4. Nov 6, 2015 #3


    Staff: Mentor

    With 150 amps of solar panels and deep discharge batteries, you should be able to supply 60 amp-hours of energy per day at the latitude of Florida/Arizona. At the latitude of Maine/Seattle, you need 50% more panels. On stormy days with thick clouds, your panel will only make 25% as much as on a sunny day. So, Russ Waters is correct, you don't have enough panels or enough batteries for a continuous 5 amp draw.

    Six batteries and 400 watts of panels will be closer to serving your need, or you can maybe use a smaller amp or turn the volume down, or run it only part of the day.

    That 2000 watt inverter is huge. In a few minutes it will suck up all the energy your panel makes in a day. Figure 1 kwH per day for 200 watts of panels. Also figure that inverters are only 50% efficient.
  5. Nov 6, 2015 #4
    ah okay so you think if i get another solar panel think it be better ? like another 150 or 100w solar ? plus more batterys ? the cctv i can make it go to 12v 2amps
  6. Nov 6, 2015 #5


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    Gold Member

    The solar panel power rating needs to be 4-6 times that of the load if you want to run the load 24/7. You indicated a 60 W load (120V,5A), so you need at least ~300 W of new PV panel array, or 360 W on the nameplate to still be producing at least 300 W twenty years from now. Depending on your latitude, you'll need less PV in the summer and more in winter, and more still on cloudy days. If you want the most power averaged across the year, mount your panels south facing at an angle equal to your latitude. If you want to buy just enough panel to maximize winter production at the expense of a lower annual average power production, mount the panels more steeply.

    As RussW indicated, the 60 W may be the *rating* of the DVR, i.e highest momentary load, but its average draw might be considerably less. You'll likely have to measure the DVR amps to know.
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