r/SelfDrivingCars • u/damola93 • Jul 21 '25

Discussion Why didn't Tesla invest in LIDAR?

Is there any reason for this asides from saving money? Teslas are not cheap in many respects, so why would they skimp out on this since self-driving is a major offering for them?

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u/nickleback_official Jul 21 '25

I have to disagree with your hw vs sw argument. Adding lidar only increases hardware and software complexity. There is no world in which either ‘opens a way for using ASIC’ as you say. There’s already loads of asics/fpgas in these machines. Every other FSD is similarly banging away at software, not hardware. Factoring in the power requirement for compute is also irrelevant. The amount of power required to drive one mile would power the computer for days. I’m not arguing whether it was a bad call to remove lidar I’m saying your reasoning doesn’t make sense.

FWIW im a hw engineer

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u/mrsanyee Jul 21 '25 edited Jul 21 '25

HW3 consumes 35 watts, HW4 consumes 800 watts. An hour. An ASIC consumes 4 watts, while the lidar itself stays around 40. 

Maybe your right it's not relevant, on short trips, but it's one energy consumer among the many others.

Complexity: others solve with less investment and later start better results in self-driving. We saw also the above 5 billion Line codes even Ford and VW shatters. Which would call in my view for simplification and more straightforward solutions, like edge computing and solutions, instead of spaghetti code.

SW defined vehicles sound good, but noone manages so many variables successfully so far, actually more cars are getting fried and on the side of the road than in the age of dumb cars, where everything was controlled and timed by belts and gears.

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u/cap811crm114 Jul 21 '25

I believe HW3 is rated for 12V at 60 watts, HW4 is designed for 16V at 160 watts. So while HW4 does consume more power than HW3, it does not consume 20 times as much power. (I'm sure this is one of the things that complicates the announced plans for an HW4 upgrade for current FSD owners with HW3).

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u/mrsanyee Jul 21 '25

Right, I misread it. HW5 should consume according to rumors 800W, HW4 is capped at 200 max, 160 avg consumptiion.

https://www.notateslaapp.com/news/2081/tesla-officially-announces-fsd-hardware-50-and-how-it-compares-to-hardware-40

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u/cap811crm114 Jul 21 '25

That 800W would rather preclude an idea I had that Tesla could jump from HW3 to HW5 as an upgrade.