Fearless Solar Tracker - Snowy Sunday Solar Stuff

[wtam69]

Nice and neat setup you now have. I remember when you used to have just one panel.

[Fearlessthinker]

@wtam69 I fear in a year you'll comment that you remember when I only had 6 panels. ;-)

[mjlorton]

Brilliant...how about a sunrise to sunset time lapse of the Fearless Tracker... :)

[Fearlessthinker]

@mjlorton I've never tried to do one of those.  That would be cool. I'll look into it. Thanks.

[EarthshipFreedom]

Great set up!

[dwm10251a]

Do you have a spreadsheet of the economics of all this hardware? I just started following you. I have a spreadsheet of panel economics only for my local utility bill and my particular lighting and appliances. I plan to make a video and share it.

Don

[Fearlessthinker]

@dwm10251a Um .... no. It's been a hobby and I haven't used rebates or credits. I do however get good deals on things, and many of my parts (all the GTIs and the charge controller) were used when I got them. Still, I should run the numbers now that I have some production data. The WANF meters provide total kWh and total days, so those can be used along with my utility rate do some calculations. The main economic benefit for me has been the paid consulting work that has resulted. Thanks.

[electrodacus]

Exterior temperature is not important on solar PV energy output the colder it is the better. 

[dwm10251a]

@electrodacus In central Texas I know we'd get a lot of sun in summer but it's hot air temp. I'll have to read up on the physics of PV.

[electrodacus]

@dwm10251a In the summer when is hot outside and the panels get hot the efficiency will be reduced so they will put out less than if they where cooled and with the exact same sun.

Solar tracker is good it can give you 20 to 25% more energy than a south orientated panel (that if you live in northern hemisphere)

100W PV + tracker or 120W PV will produce similar output so the less expensive of this two setup wins.

20W of PV at 3$/W cost 60$ so the tracker need to cost less to worth the investment.

[Fearlessthinker]

@electrodacus You have a good point, but I think the 20-25% figure is too low, especially if the tracker can cover sunrise to sunset everyday of the year, which for my location is a sweep of as much as 251 degrees. Many trackers cover less than 180 degrees. I hope to test fixed vs. tracking on the same day with 2 identical panels to at least get a sample measurement. Good comment.

[electrodacus]

@Fearlessthinker I do not have direct experience as of now but this seems to be the value others come to. See this on-line calculator rredcDOTnrelDOTgov/solar/calcu­lators/PVWATTS/version1/ has data on most locations on the globe is fun to see how it differs over the globe and there is an option for one axis or two axis tracker.

Same thing as for tracker apply for MPPT if is to expensive over PWM then it may be more convenient to get more PV they went down in price quite a lot.

[Fearlessthinker]

@electrodacus I've actually done at least one video featuring PVWATTS, it's a good general guide but I have talked to actual tracker users and in most areas they do far better than PVWATTS predicts. That is why I think we need to collect our own data sample if we can. If you live where there is fog many mornings, or live near mountains where there are "high horizons" then you can do far worse than PVWATTS predicts too! Thanks.

[electrodacus]

@Fearlessthinker The data there are quite old from the 70 to late 80 also there are some parameters that you need to input one of them is DC to AC derate factor that is 0.77 and depending on your cables and charger or inverter efficiency you can get better.

Also each year is quite different but is a good calculator to be able to size your array.

And of course if the solar panels are not clean (snow, ice) in winter you can get much less.

Hope I will be able soon to build my of grid house.

[shartne]

At what time of the day did you see the biggest difference between the tracker and the panels facing due south? Is there going to be a twin panel to set up with the single tracker panel next to double the results or how many do you think you can get up there? I guess you can just add them as you go to find out what works the best. Is it a 120 watter on the tracker?

[Fearlessthinker]

@shartne It turns out PV panels don't really need to be perfectly aligned with the sun. Tests show that even if they are 30-degrees misaligned, that 87% of the power still can be produced. This assumes a noon sun, as there is less atmosphere to get in the way. I did not measure it, but I suspect the early morning is when I see the largest difference, fixed vs. tracking, but that would make a good test. I think I can put 2 x 120w, or one 240w panel, on this rotator, but that's likely it.

[Xringer]

At the start of the video, those panels that were only doing a couple of watts, kinda makes me wonder.. Were they making or USING a couple of watts?

Because, maybe the GTI wasn't getting the full start-up power it needed from the PV to actually start putting some power onto the grid..?.

I've heard the PowerJack GTIs eat a good bit of power, if left plugged in at night..

[Fearlessthinker]

@Xringer It is true that the GTIs were just on the edge of converting power at dawn. You can see the activity lights just perking up. It is not true that they eat power at idle. My WANF power meters are all reading 0.0 - 0.2 watts, currently, and it is in the middle of the night here. They measure power going in either direction. Good comments, so thanks!

[Fearlessthinker]

@water4fuelh20 Thanks. We each contribute what we can, and together we are changing the world bit by bit. As for your heaters ... perhaps consider a "superlight" version design for 2012 that tracks or has reflectors that track.

[definitionofis]

That's great. I like it. I took your advice and added my wind turbine weights at a shorter radius.

[Fearlessthinker]

@definitionofis Cool! ... Note to my subscribers, definitionotis has some great videos ... check him out! He is an expert in many things and recently in solar thermal.

[MrHorsetail]

You're having too much fun with that. You could make a shadow stick to see if your elevation is correct.

[Fearlessthinker]

@MrHorsetail Well yes I could, but I'm afraid I'd be out there adjusting it all the time. Turns out there is only a 2% loss for being off 10-degrees in azimuth or elevation, so I'm not going to sweat it.