DIY Solar panel tracker - need help..

strange fruit in the garden.



this is a little 5 watt toy to test our time based tracker.

hoping to get some good storms (electrical) through here to give it a good test.

cheers, dave

update.

not sure if there is still any interest in a diy solar tracking solution.

its been over two weeks since we reported deploying our prototype tracking array for testing. the thread has been viewed 400 times since that time and ive recorded traffic to my project page- so will assume someone may still be interested.

now.. two weeks of testing is not two years or even two months, but this is our findings so far.

the array moves to its assigned locations at its set times. stepping through the sky in 10 degree western increments throughout the day and returns back to the east at the end of the day to repeat the same thing the next day..and so on.

the gains measured (dave with cheap watthour meters) from the tracked array and several non tracked matching arrays seem to be in the 30% range.

one big surprise is the gains measured on the not so pv friendly days, the days of overcast and rain that the sun never breaks through.
on these bad days the tracked module can make real power gains. from almost no output on the non tracked arrays to useable power on the tracked array. gains in the 200% range and better were noted.

a few observations made during testing.

curious neighborhood dogs are bad.

weep holes in the corners of junction boxes are good.

measuring array output while the battery is under load is good.

lawnmovers mixed with ground mounted pv arrays are bad.

curious neighborhood kids are good.

thinking that wooden stakes driven into the ground will stay aligned is bad.

the cool factor of a tracking array is good.

on to phase two.

cheers, dave

I just chased you over here from Fieldlines. Pretty neat project.

Im using off the shelf redrock trackers with good results but we average 300+ sunny days/year at my location. A timed tracker may indeed be a better choice for a more cloudy location.

This timer is the thing Im most interested in. I have a few 24/7 loads here that Id like to switch off, especially at night. Can you confirm that the thing actually switches, using only the CR2 battery, and no AC? Also, you think the battery might last for years doing this daily switching? If so, I have really been looking for a timer like this!

Volvo Farmer

hi volvo farmer,

300 plus days of sun sounds like a nice place to live with pv power. and a perfect match for a controller that tracks with light sensors.

as for this timer, if someone told me this prior to august.4th i would have said no way...but i can absolutely confirm that this timer runs stand alone, full function, without any outside power source of any kind be it grid or otherwise.

can i explain it? no. in fact this has had me totally baffled for over six weeks! this CR2 battery is 3volts and 800ma thats a grand total of 2.6whs. i have one of these timers here on the coffee table that i have cycled upwards of 10,000 times so far! if i thought i was sure i could explain it i would have taken a clam knife to it by now..still may! heres a bit of speculation, they may be capturing the coil collapse energy somehow?

on of the first things we did was to power one of these timers up with a series pair of D cells with no trouble. also, i bet even i might be able to work up a stable 3volt supply from our battery bank if it proved necessary. this timer is a hidden gem to us involved in these battery based systems..on a sad note the company just destroyed about 400,000 of these timers in a recall because the old model had the ac (when used in ac applications) exposed..so when people were changing the batteries..bad things would happen.

so many things are still a mystery to me.

kind regards, dave

Thanks for the reply. Im gonna get me one of these and play with it

Six weeks is a good enough time trial for me. I think Id like to try and use one of these for a defrost timer in my refrigerator too. Our fridge only uses 1.1KWhr/day, but if I could force defrost into mid-afternoon, when the sun is shining and batteries are floating, instead of randomly seeing the thing in defrost after the sun is down, it would make me happy.