Earths glorious/cursed orbit...

CALLD
CALLD Solar Expert Posts: 230 ✭✭
Alright ok alright - I know 99.9% of you are rubbing hands with glee this time of year, but spare a thought for your brothers down south...

Rapidly shortening days, sun slipping north at a rate of over 42km/26miles per day, power declining noticibly day by day on the meters. It's a reality for us all at some point of the year (even those of you lucky enough to reside in the tropics - the dreaded wet-season).

There is an upside though for me - cooler weather means less aircon use and lower refrigerator demand. Panels also operated at higher efficiency.

Have to start adjusting loads now - what are you guys in the north doing? Switching on as much as possible no doubt hehehehehe:)

Comments

  • verdigo
    verdigo Solar Expert Posts: 428 ✭✭
    Actually I was making more power in the colder weather on the clearer days, but as of late there have been more of the clear days.
  • BB.
    BB. Super Moderators, Administrators Posts: 33,613 admin
    We in California (South West US), are running short on water/rain/snow. Heard today that we are at 5% of normal for snow in the California Mountains. State Governor has mandated 25% water reduction (that details are probably going to be ugly and unfair--Generally these restrictions hurt those who have been been conserving with a lower average consumption start rate--And those who have been "wasting water" have higher average consumption as the starting point for 25% reduction).

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • cupcake
    cupcake Solar Expert Posts: 254 ✭✭✭
    Here in the desert the panels produce less as it heats up and the days get longer...

    So it's not what you may think...

    When it gets to 120F here the panels drop to 40%-50% output...
    ~1.5Kw PV in parallel
    Morningstar MPPT-60 controllers (2) in parallel
    3 Trojan tr-1275's in parallel 450ah total
    Samlex 2,000 watt 12-volt inverter hardwired


  • Alaska Man
    Alaska Man Solar Expert Posts: 252 ✭✭
    I'm starting to run my fridge and freezer again, during the transition times I have to run heat and refrigeration which does strain the system. Usually I run one or the other. The good thing is that when I have to start running both at this time of the year, I'm getting lots of help from Ole' Sol. Days are around 13.5 hours right now. Screaming on to the Midnight Sun Festival. Soon enough I'll be fishing in the daylight at 2:00 AM.
  • Dave Angelini
    Dave Angelini Solar Expert Posts: 6,891 ✭✭✭✭✭✭
    BB. wrote: »
    We in California (South West US), are running short on water/rain/snow. Heard today that we are at 5% of normal for snow in the California Mountains. State Governor has mandated 25% water reduction (that details are probably going to be ugly and unfair--Generally these restrictions hurt those who have been been conserving with a lower average consumption start rate--And those who have been "wasting water" have higher average consumption as the starting point for 25% reduction).

    -Bill


    The california desert near arizona is doing well in the drought. Too bad it is a desert.
    "we go where power lines don't" Sierra Nevada mountain area
       htps://offgridsolar1.com/
    E-mail offgridsolar@sti.net

  • Dave Angelini
    Dave Angelini Solar Expert Posts: 6,891 ✭✭✭✭✭✭
    cupcake wrote: »
    Here in the desert the panels produce less as it heats up and the days get longer...

    So it's not what you may think...

    When it gets to 120F here the panels drop to 40%-50% output...


    There are solar panels designed with very gentle power drop-offs at temperature BTW.
    "we go where power lines don't" Sierra Nevada mountain area
       htps://offgridsolar1.com/
    E-mail offgridsolar@sti.net

  • CALLD
    CALLD Solar Expert Posts: 230 ✭✭
    cupcake wrote: »
    Here in the desert the panels produce less as it heats up and the days get longer...

    So it's not what you may think...

    When it gets to 120F here the panels drop to 40%-50% output...

    That seems like a lot to lose due to temperature alone, what is the low temp you're comparing the high temp to? I've seen a maximum clear sky production shift of 15% with a 35°C difference in panel temperature with identical irradiance. The 35°C temperature change was achieved simply by hosing down the array on a calm and blistering day in the middle of summer. Production climbed from 1250w to 1430w after the cooling. Array voltage rose from 75v to 86v while current remained more or less the same at around 16 to 17 amps. The panels in question are polycrystalline.

    Btw I've seen a lot of production lost to hazy conditions - conditions ordinary folk would still call "sunny", but to us solar folk we know when the sky goes milky white the light hitting the ground is a lot dimmer. Also I've witnessed a lot of hazy and dusty weather during my visit to the Sahara in 2010. Lots of hot weather but not much in the way of powerful crisp sunshine...