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by Jedd 88 days ago
> The solar energy you can collect is about 750W/sq meter.

> A car roof is about 5’x5’, and if we are generous and include a trunk and hood area, maybe you are getting 60 sqft?

We must think metric, every inch of the way!

Anyway, PVCs currently max out at about 300W / square metre - and that's in ideal conditions.

I believe theoretical maximum energy per square metre (when light actually arrives at the planet surface) is conveniently pretty close to 1000W, assuming you're in the right place, but maximum efficiency of contemporary panels is only about 30%.

2 comments

There is a tiny image hidden at the bottom on one of the race team pages which represents an interesting effort towards a road legal solar car.

https://en.wikipedia.org/wiki/UNSW_Sunswift#/media/File:Suns...

They are now working on the sunswift 8 which is to be a combination of solar battery and hydrogen.

They are not calling it a solar car anymore apparently.

https://www.unsw.edu.au/challeng/vertically-integrated-proje...

Pure solar is indeed to much of a constraint, it make it more challenging than propelling humans over roads in an enclosure needs to be.

A big problem is sharing the road with conventional vehicles. Many could probably drive straight though it, a Tesla could probably drive straight though it.

If the car must be a strong metal container the choices quickly reduce to the things on the market right now.

Totally agree, SI units for the win!

I was just trying to use “familiar” units. I could have led with 1 HP per square yard, and then you’d totally have license to call me out!

And yeah, I was just talking about solar flux, there’s a whole lot of real world losses to consider but my point was that none of this matters, it’s orders of magnitude away from ICE engine output.

It was the fact you started using units the world knows - albeit misspelling metre - but in the next sentence, comparing that same dimension, you used an apostrophe to allude to a unit that only 5% of the planet uses.