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[Angel And The Wolf]

Originally Posted by Shortie771

Not sure why I said trackers take up more space in my previous post... Still waking up I guess.

Thanks for doing the numbers.If you mount each panel separately, you Do have to worry about each panel throwing a shadow. I guess that is why you said that. To make economic sense, you would have to DIY your tracker, like the gentleman in the video. Yes, a commercial tracker is too expensive.

[Snax]

Yep, ultimately from every angle I've tried to approach it: If you have additional space, just adding more stationary panels has a higher payoff.

Even large local utility arrays play by that mantra.

I could build something, but it is definitely in the realm of hobby to do so.

[Angel And The Wolf]

Originally Posted by Snax

If you have additional space, just adding more stationary panels has a higher payoff.

If you don't mind me asking, how much did you pay for your panels?

[Snax]

Then there is the idea of using mirrors like this -

How to boost any solar panel output by 75%

I had a different spin on the idea just a bit ago however that would actually work, again with the added complication of a tracker: Move the mirrors instead.

Something like this with a diffuse reflecting surface to better scatter and prevent hot spots. If the reflectors track inline with the sun, there is no shadowing, and much of the light reflected off the surface is scattered back to the panels.

[Snax]

I think that is the best in terms of both maximum output and minimal complexity without overheating panels.

Another spin on this idea would allow for the reflectors to act as covers or fold down against the panels in inclement weather.

[redpoint5]

Would be neat to use mirrors to boost solar output, and then use water for liquid cooling the panels, that then gets used as hot water.

[Snax]

Originally Posted by Angel And The Wolf

If you don't mind me asking, how much did you pay for your panels?

I don't really have a cost breakdown on the panels for the existing system. I paid to have them installed before the end of 2017 when the 30% state tax break expired. I was in a rush, so didn't haggle, but it seemed to jive with other installs I had read about. I probably paid a $10k premium for the labor and everything, but all of that and then some came back in the tax credits. My net out of pocket ends up being about $5700 on 4.96kW with a SolarEdge optimizer system. (SE is similar to microinverters, but with DC optimizers, that cost less instead of converting to AC at the panels as Enphase does.)

For the new system, I am going to go with microinverters by APsystems, which are about half the price of Enphase. It ups the cost a little, but with a 240V bus on the roof and down to the panel simplifies the electrical substantially. I was quoted $7200 shipped for a 5.4kW DIY kit just yesterday including RENVU doing the permitting for me.

DIY for the shed as well, figuring about $3500, almost $11k total out of pocket. But 30% would come back to me from from the feds, knocking that down to $7700. Factor in the tax deduction for the HELOC as well, and it will probably be just shy of $7k total out of pocket.

That is probably a touch on the high side, but RENVU is making it really freaking easy by including virtually everything I would need to DIY short of the structure to mount it and labor.

[Angel And The Wolf]

Originally Posted by redpoint5

Would be neat to use mirrors to boost solar output, and then use water for liquid cooling the panels, that then gets used as hot water.

I think you are talking about this:

https://www.youtube.com/watch?v=MYmfF4Sqc3g

Of course, standard solar cells can't handle 2,000 suns, but they can handle several. Haven't been able to read their limits, but you could experiment with a
flipped solar cell and several flat mirrors. The one below will reflect 2 suns onto the solar panel. Use four (one on each side) for four suns. Coll the panel's back side with water, and run that water to a hot water tank.

[Angel And The Wolf]

Thanks, SNAX.

[RedDevil]

Beware - I read more than once that using mirrors to boost PV panel output voids their warranty. And if you have the space to put them down, just adding PV panels equal to the cost of the mirror system may boost the output just as much.

I had another idea, which is to use powered mirrors to reflect sunlight (and infrared) towards your windows as a means of heating your house in winter. I do not know how effective PV panels mirror IR, but if they do it could be double efficient that way.

The downside is extra light in your house, and of course it does little at night or when overcast (although IR penetrates clouds better than visible light does, so some heat will find its way). Also, the most effective setup would be north of your house (in the northern hemisphere, or south down under) where there probably aren't big windows.