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Driverless Cars Are Giving Engineers a Fuel Economy Headache (bloomberg.com)

schwit1 shares a report from Bloomberg: Judging from General Motors' test cars and Elon Musk's predictions, the world is headed toward a future that's both driverless and all-electric. In reality, autonomy and battery power could end up being at odds. That's because self-driving technology is a huge power drain. Some of today's prototypes for fully autonomous systems consume two to four kilowatts of electricity -- the equivalent of having 50 to 100 laptops continuously running in the trunk, according to BorgWarner Inc. The supplier of vehicle propulsion systems expects the first autonomous cars -- likely robotaxis that are constantly on the road -- will be too energy-hungry to run on battery power alone. A fully autonomous subcompact car like a Honda Fit, for example, will get 54.6 miles to the gallon in 2025 in the best-case scenario, more than 5 miles below the U.S. emissions target, according to BorgWarner. A small pickup or SUV would be at 45.8 mpg, versus a target of 50. Engineers don't have much time to resolve this, as companies are planning to deploy their first fully self-driving cars in the next couple of years. One way for automakers to meet the power-hungry needs of self-driving systems will be to use gasoline-electric hybrid models rather than purely electric cars, said Mary Gustanski, chief technology officer of supplier Delphi Automotive Plc's powertrain business.

13 of 208 comments (clear)

  1. Didn't consider miniaturization? Moore's Law? by bit+trollent · · Score: 5, Interesting

    Really? These engineers didn't consider that processing power is constantly shrinking and becoming more efficient?

    I feel like I'm reading an article from 30 years ago about how computers will never fit inside your home because the take up large rooms!

    1. Re:Didn't consider miniaturization? Moore's Law? by ShanghaiBill · · Score: 5, Insightful

      Really? These engineers didn't consider that processing power is constantly shrinking and becoming more efficient?

      Also, the claim that SDCs will have computers consuming 2-4 kw seems implausible. Tesla Autopilot consumes WAY less than that, and is doing basically the same thing in terms of processing sensory data. Waymo will have access to TPUs that can process vision data eight times more efficiently than GPUs, which themselves consume no where near 2kw. There may be some heavily instrumented prototypes that have 2-4kw of computing power, but that doesn't mean the production version will do that.

    2. Re:Didn't consider miniaturization? Moore's Law? by viperidaenz · · Score: 4, Insightful

      Tesla Autopilot is not much more than lane keeping and auto cruise control.
      It can't handle cross traffic without crashing into a truck. It's designed to only be used on motorways. It can't drive through a city. It can't read signs at an intersection to determine who gives way.

      Autopilot != self driving. It does exactly what an autopilot does, keeps you on course at the correct speed, and hands back control to the pilot when it detects a scenario that requires a decision.

    3. Re:Didn't consider miniaturization? Moore's Law? by mysticgoat · · Score: 3, Insightful

      You are on to something with safety in redundancy through separate virtual machines.

      Except of course for the "virtual" part.

      There has to be physical redundancy such that there is backup when something bricks one of the computers. As will happen every so often when self-driving cars are doing millions of highway miles each year. Additionally, self-driving cars need enough AI to bee able to identify the car ahead in the fast lane with the nearly flat rear tire is a threat; that the hail that is bouncing off the road a hundred yards ahead is a danger; and that little Timmy in the back seat who is making urrping noises means that there is an urgent need to stop on the shoulder so you can get his head out the door before he pukes.

      The computer network that has the smarts to handle all the stuff that can happen on the road will easily require 4 kw power, including the cooling system that will keep it functioning when you are stuck in the commuter traffic jam.

      As far as driving on the open road is concerned, the best we can hope for in the foreseeable future is improved auto-pilots, that will still require a trained and experience driver, who is alert and paying attention, behind the wheel.

    4. Re:Didn't consider miniaturization? Moore's Law? by NicknameUnavailable · · Score: 4, Informative

      While it is possible that current designs are using 2-4kw, I'm not buying it is a long term problem. Optimize the software.

      It's possible it's not even mostly software. LIDAR powerful enough to cut through an intense hailstorm or overpower noise/reflections from other self-driving cars from its perspective could easily break 2KW.

  2. Easy Solution by freeze128 · · Score: 5, Funny

    The answer is simple: Outsource the processing power to an overseas call center where your virtual driver (Let's call him 'Steve') will steer the car in a simulator-like environment. A few webcams around the car will certainly use less power than that huge LIDAR pod on top of WAYMO cars.

  3. Self driving tech is a waste of money by SumDog · · Score: 4, Insightful

    Self driving cars in Europe might be neat where they don't have transportation shortages. In America, our mass-transportation infrastructure is non-existent. Except for a handful of cities, you have to own a car in order to simply function in society, or you have to find a job that lets you work from home or live in a very limited area of town.

    I wrote a post about this a while back:

    http://penguindreams.org/blog/self-driving-cars-will-not-solve-the-transportation-problem/

    Basically even if you had Interstates which only allowed self-driving cars and all of them could travel at over 120kph bumper-to-bumper and all of them were filled with four people each, you still wouldn't even get to 10% of the capacity of a traditional rail system, running on a single track, with trains arriving at 5 minute intervals (and most cities with rail systems have them arriving at 2 min intervals during rush hour. London has several automated trains. Singapore is fully automated).

    Before we start dumping billions into subsidizing self driving cars, how about we build up our self-driving train tech; a known technology which currently exists and transports millions of people every day.

  4. Big-rigs will be the first autonomous vehicles by ebrandsberg · · Score: 3, Interesting

    Consider: Many long-haul trucks operate mostly on well maintained highways between distribution centers. Ten or more of them could be linked together scanning for issues, and communicating with each other, possibly with a lead car in the front that can react to accidents and incidents before they even pass, similar to over-sized loads on the road today. Even if not driving between distro centers, they can use existing rest-areas as stopping points where local drivers can take over in shifts.

  5. Re: Very inefficient programming then by Anonymous Coward · · Score: 3, Insightful

    How much power does the omni directional LIDAR array of your cluster use? Oh, it doesn't have one that works at highway speed and distance, much less allow for cross traffic?

    Well then, my welcome mat at home uses zero power and is about as relevant as your anectdote. Thanks for telling us all about your cluster. Do you not have a TV? Oh wait you must, because you would have told us if you didn't. You are that guy.

  6. Nonsense by crow · · Score: 4, Interesting

    This is calculations based on wild assumptions about what is actually required for self-driving. If Tesla is right, then they can do it with the hardware that is already shipping, so power is not an issue--they just need to finish the software. You can also look at what Nvidia just released that they're billing as being designed for self-driving cars. AMD is apparently working on a similar product.

    This sounds like a typical naysayer making stuff up to get attention (and advertising hits).

  7. They didn't do the math by locater16 · · Score: 3, Interesting

    A Tesla Model S has a 90 kilowatt hour battery life for it's 275 mile range. A kilowatt hour is a thousand watts, and let's assume you're going 60mph. For argument, and maths, sake we'll assume you're going above efficiency and say you'll get 240 miles out of that. That's 4 hours, so 22.5 kilowatts an hour. That's a powerdraw of 22 thousand watts in 1 hour. The new self driving chip announced by Nvidia only draws 500 watts, that's 500 watts in an hour. Or better yet, here's the empirical evidence of Tesla owners discussing their average watts/min usage: https://forums.tesla.com/forum...

    Even there with more efficiency, the new Nvidia chip uses in an hour less energy than the car itself uses in 2 minutes. This article is absolute bullshit, they had 1 damned thing their job required and they didn't do it. Self driving electric cars are perfectly mathematically sounds.

  8. Re: 2-4KW my ass by Dog-Cow · · Score: 4, Funny

    Have you tried?

  9. Re:Not Another Story About Driverless Cars by kamapuaa · · Score: 4, Insightful

    The sort of person who lives at point A, and works at point B, and has to get up in the morning to drive the same route from A to B and then later in the day drives from B to A every day. Driving is an hour and a half a day (mostly) wasted. If I could sleep or work or jerk it for an extra hour and a half every single workday, I feel like my quality of life would be improved. Just that alone would be an extra 400 hours/year.

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