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electrical:solar:rationing

Words of Wisdom: It is cheaper and easier to use less power than it is to make more power. – highdesertranger1)

Rationing solar power

Sometimes normal awareness is not enough to keep a solar setup functioning with usable power. In these situations one might need to take steps to minimize loads and maximize power generation.

Here are some examples:

  • smaller solar installations
  • a stretch of rainy days
  • a forest campsite with no good access to sunlight
  • smoke from forest fires
  • very short winter days

minimizing loads

  • find and eliminate parasitic loads
  • make it a habit to turn off anything you don't need right now. Channel your Inner Dad who says “turn off the lights when you leave the room!” :-)
  • timeshift charging of phones, laptops, etc to periods of excess power
  • charge light sources during full sun and use them at night
  • go to bed with the sun, rise with the sun
  • use low-power entertaining like reading instead of power-hungry entertainment like TV, gaming console, etc
  • turn down screen brightness on phones, tablets, TVs
  • Inverters
    • minimize the use of inverters by using 12v appliances and adapters when possible
    • turn inverters off when not in use
    • size the inverter to meet the needs of your biggest loads. Oversizing wastes power because bigger inverters have more parasitic draw. It may be worthwhile to have a small inverter for small loads and a big inverter for big loads; this stops the inefficient use of small loads on a big inverter.
    • use MSW unless your intended uses need PSW; MSW have lower parasitic draws.
  • open your refrigerator as little as possible after sundown
  • cook with propane instead of electricty

maximizing solar harvest

  • ensure the panels are not shaded by natural obstructions: move out from under trees, overhangs, etc.
  • ensure the panels are not shaded by manmade obstructions on your own RV: antennas, A/C units, vents, etc. One way to minimize shading is to park so that the greatest expanse of panel is facing south and any obstructions are on the north side of the van.
  • tilt panels if possible
  • ensure no tarps, awnings or other obstructions are preventing cooling breezes from passing under/over the panels; panel output drops as cell temperature rises.
  • framed panels (mono and poly) should be mounted with some space underneath them for cooling airflow. Cell temperature affects panel voltage output.
  • clean the solar panels. Dust or dirt on the panels can decrease panel output by 5-10% in some cases.2)
  • tweak your PWM controller to produce more power, and be ruthless about not running loads until the battery bank is out of bulk mode.
  • invest in an mppt controller if you can, and configure it to battery manufacturer specifications
  • install an isolator for alternator charging
  • use shore power charging (via converter) anytime it is available
electrical/solar/rationing.txt · Last modified: 2019/12/13 04:33 by frater_secessus