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No, that could easily happen. The parent was right, that panel should be secured in some way. Wind gusts can do some crazy things.
First, there are no hurricanes or tornadoes in that area. So, you can work out max wind via historical data, but 85MPH is not going to be enough to move it over that lip. The skin effect around a building drastically reduces the forces involved.
These already exist as self-contained kits: https://www.amazon.com/dp/B00GV3XRDW/ref=asc_df_B00D5RVMAM50... What I think would be interesting is to use a relay to fall back to grid power once the battery dies.
For heating, you could bring in a small refrigerator rather than a resistive load. Get something besides heat for your power.
I built a very similar system into my Jeep-house. I have two 100W panels on the pop-top roof, a charge controller and a dedicated solar battery (isolated from the engine-starting battery) that runs my fridge, water pump, UV treatment lamp, interior lights, air compressor and charges all my electronics (laptop, kindle, cameras, etc.) directly from 12V DC. I can leave the Jeep parked without running the engine for days…
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You really need to stop replying to every reasonable comment pointing out a very real risk with all this ignorant nonsense. You know not a thing about air flow on that roof (or anyone else's), and you seem to be utterly clueless as to how powerful even mild gusts of wind can be. Trying to convince people they DONT need to take reasonable safety steps, even when presented with knowledgeable arguments that are clearly…
Run some actual math > fear. Yes, in a slightly different situation this would be an issue. But, wind is not magic fairy dust that can lift arbitrary loads.
Just stop with the flawed logic.
Quite a side note: If you're renting in SF, your landlord needs to provide you with heating ( http://sfrb.org/topic-no-257-minimum-heat-requirements )
Please bolt the panel down, if wind picks it up and blows it off the roof it could easily kill someone.
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>I really doubt the wind is going to pick up a 2'x4' ~20lb panel like that when it's flat on a roof. thus the difference between the air speeds over the panel and under the panel in this case equals to the wind speed. To compare - Cessna wing loading is 15lb per square foot and it is generated at the minimum no-stall speed required by the FAA for general aviation of something around 70 miles/hour, and in that situati…
That's not how wings work. https://www.grc.nasa.gov/www/k-12/airplane/wrong1.html Most obvious problem aircraft can fly upside down.
"{The upper flow is faster and from Bernoulli's equation the pressure is lower. The difference in pressure across the airfoil produces the lift.} As we have seen in Experiment #1, this part of the theory is correct."
Re-read my original comment - it is pretty much stating the same as the cited text above.
The link you posted refutes the "Equal Transit" Theory which is deriving the speed difference from the wing asymmetrical shape using very simple approach. Which has nothing to do with my original comment as i was applying the [correct according to Bernoulli law and your link] theory of pressure difference generated by airflow speed difference to airfoils without regard to whether they assymetrical (Cessna wing) or symmetrical (solar panel).
Will the landlord notice? Maybe not. Will the wife notice all the wires all over the place? You bet!
Because men love electronics projects and women love keeping a tidy house and ruining their dreams, am I right?
I don't think this is accurate. Personally, I've had a lot of trouble finding people of either gender who are interested in electronics.
I might be overstepping here, but it sounds like maybe you should talk to you wife and see what can be done to minimize the negative externalities caused by your hobby? It's hard to imagine she would actually want to ruin your dreams. I don't have a wife, but I know my girlfriend became a lot more supportive once I started keeping half-finished projects in the spare bedroom, and started putting in an effort to clean up my projects a bit more before letting them out. Just my $0.02 obviously.