Cybertruck with massive solar panels

Newton

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p̶r̶i̶u̶s̶ c̶,̶ y̶o̶t̶a̶ p̶i̶c̶k̶u̶p, ⼕丫⻏?尺セ尺ㄩ⼕长
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people keep posting this. its super cool for sure.

27 sqmtrs is 290sqft, panels r about 3lb per sqr ft = 870lbs

*note, I could be doing this wrong.
each panel is about 17sqr ft, so 17 panels i think they are 300watt's x17= 5100watts so about 5kw/h
if tesla battery pack is 100kw/h it would take 20 hours in direct sun to charge fully


mounting with sliding rails, and electronics would be another probably 1000-1500lbs maybe {just guesstimating really}
so total weight about 2000-2400lbs( a mazda miata weights about the same) i wonder how much this would decrease range
 
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Crissa

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Weight doesn't decrease range as much as you might think. Since regen gets you it back when you stop, more weight means more regen.

But still... panels can be super-light, the actual cells are light, it's the frame that weighs.

My latest panels weight about four pounds per 40w panel with mounting gear, which is about three square feet.

But ultra flexible panels meant to be mounted on steel (or like the vault) or even raw cells are about a tenth of a pound per 100 watts.

So the raw cells you want would weigh like five pounds. We're talking paint weight at that.

-Crissa
 

Newton

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p̶r̶i̶u̶s̶ c̶,̶ y̶o̶t̶a̶ p̶i̶c̶k̶u̶p, ⼕丫⻏?尺セ尺ㄩ⼕长
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oh yea, im sure it can me made extremely light. We could make the whole frame and (most) mechanisms out of carbon fiber wrapped foam, or something like that. but I was just giving a very basic, if i went and made it right now weight and specs, not thinking about optimizing anything.
 

ajdelange

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Weight doesn't decrease range as much as you might think. Since regen gets you it back when you stop, more weight means more regen.
Lets say you are driving on the freeway at 90 kmph and see the opportunity to accelerate to 110. Consider a 1000 kg component of the load. The energy you must deliver to that to speed up these 20 kmph is
1000*(110000/3600)^2/2/3600 - 1000*(90000/3600)^2/2/3600 = 42.8669 Wh
You get that from the battery. But the car is not 100% efficient so you actually draw perhaps
1000*(110000/3600)^2/2/3600 /0.9 - 1000*(90000/3600)^2/2/3600/0.9 = 47.6299 Wh.
If you have to slow back down to 90 kmph that energy is lost to drag and or the brakes. If you have to do this twice per mile that's 95 Wh per mile per 1000 kg of load so for a 2500 kg X it would be 238 Wh/mi. Thus in situations where acceleration and deceleration are necessary the inertial load is the largest.

Were perfect regen available we would get the 43.9 Wh back when we slowed back to 90 kmph. But the machine is no more 100% efficient as a generator than it was as a motor. Using the same 90% efficiency number we did for motoring we would get 0.9* 42.8669 = 38.58. Thus the cost of a 90 - 110 - 90 cycle is 47.6299 - 38.58 = 9 Wh per 1000 kg. For the 2500 kg X and two episodes per mile that means an inertial load reduced to 45 Wh per mile. Much better than 238, of course, but not 0. Drag thus moves up into first place in the heirarchy of loads when regen is available.
 


hridge2020

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Last year, Zirbel and Trease collaborated with origami expert Robert Lang and BYU professor Larry Howell to develop a solar array that folds up to be 8.9 feet (2.7 meters) in diameter. Unfold it, and you’ve got a structure 82 feet (25 meters) across. Their 1/20th-scale tabletop prototype expands to a deployed diameter of 4.1 feet (1.25 meters).



Tesla Cybertruck Cybertruck with massive solar panels Solar array
 

CappyJax

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If you have to slow back down to 90 kmph that energy is lost to drag and or the brakes.
You are completely ignoring the fact that the vehicle is still moving forward while using no energy from the batteries while it is coasting. OR actually sending power to the batteries when regen braking, while again, still moving forward.
 

Crissa

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Yeah, more mass means regeneration has a longer 'sweet spot'.

It means I can two-up on my motorcycle and in the mountains here I don't see a difference in range... The numbers go down a tiny bit more up the hills but they go up much more when going down the hills.

Why the contradiction? Because regen works better at higher, longer bursts. Everything is curves, and you put weight behind your regen, and that curve becomes longer. Longer means more energy of the momentary regen is saved.

tl;dr no numbers? You're missing the effective amperage load for regeneration from your calculation.

-Crissa
 


CappyJax

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Yeah, more mass means regeneration has a longer 'sweet spot'.

It means I can two-up on my motorcycle and in the mountains here I don't see a difference in range... The numbers go down a tiny bit more up the hills but they go up much more when going down the hills.

Why the contradiction? Because regen works better at higher, longer bursts. Everything is curves, and you put weight behind your regen, and that curve becomes longer. Longer means more energy of the momentary regen is saved.

tl;dr no numbers? You're missing the effective amperage load for regeneration from your calculation.

-Crissa
What electric bike do you have?
 

Crissa

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What electric bike do you have?
A Zero!

There's a spot in the profile for people to put their vehicles. Yours says you have a Forester. ^-^ It normally shows on the left under your profile picture; if it's not showing, click on the little arrow under the profile pictures.

-Crissa
 

CappyJax

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A Zero!

There's a spot in the profile for people to put their vehicles. Yours says you have a Forester. ^-^ It normally shows on the left under your profile picture; if it's not showing, click on the little arrow under the profile pictures.

-Crissa
I was on my phone when I saw your post. I see it now on the computer.

Looks like a fun ride. You have had it for 6 years? What is your real world range?
 

Crissa

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Looks like a fun ride. You have had it for 6 years? What is your real world range?
It's my first bike! My spouse has ridden for thirty years. She got this one for me, used, last August. So I'm coming up on a year ownership and almost four thousand miles.

This is the 'three battery' 2014 which is 8.5KWh supposedly, but it gets bout the same range as the new 7.2KWh bikes. It's not the fastest electric, but beats most ICE off the line ^-^ I get about eighty-some miles of real-world range. Enough to get almost anywhere in the county and back. Freeway range is just under sixty miles.

Which is part of the reason I'm into getting an electric truck: I want to extend my bike's range, I want to do road and camping trips carrying more substantial loads, and I have a house that needs lots of maintenance and my poor Mazda 3 only holds so many bricks.

-Crissa
Sponsored

 
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