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This is a good analysis reaching a solid conclusion. The author is quite correct that the world cannot support billions of cars using long-range Lithium-based b

by nkoren 12y ago

This is a good analysis reaching a solid conclusion. The author is quite correct that the world cannot support billions of cars using long-range Lithium-based batteries. However, it probably will not need to. First: most cars are used for urban journeys, and most urban journeys are relatively short-range (roughly 12km in the US; half that in Europe). You could have a vehicle with a 30km range and it would suffice for >95% of your travel needs. Hydrocarbon fuels, with their high energy densities, made range a secondary design consideration -- there was little downside to designing for the 99.9th percentile of use cases. But range is fundamentally more costly in battery-based vehicles, which changes the design logic. I expect both users and the industry to recognise that it's better to design for the 95th percentile of use-cases, and rent larger vehicles for the rest. Second: infrastructure will be developed which mitigates/eliminates range concerns. Things like in-road inductive charging on motorways would make intercity travel possible even on a tiny battery. Third: In contrast to most of the 20th century, in the 21st century, cities are becoming denser and more walkable, public transport is generally becoming better, and younger generations are less enamoured with the car than they used to be. These trends don't look to reverse anytime soon. Fourth: Cars which require drivers spend > 95% of their lives parked. Vehicles which don't require drivers can provide taxi-like on-demand personal transport -- but as a public mode, for a fraction of the price of an actual taxi -- and they can be in essentially continuous service. Depending on the nature of the demand patterns and consumer acceptance of ride-sharing, one Robotaxi can do the job of 20-40 cars. Given the cost and convenience of such a transport system, it can be reasonably assumed that many people would forego private car ownership altogether, and rely on Robotaxis exclusively. While this wouldn't take cars off the road per se, it would certainly reduce vehicle sales dramatically (while rendering parking lots anachronistic). I expect that these trends, over the next 30-40 years, will produce a roughly 20-fold reduction in car ownership in the developed world. This will be offset somewhat by still-rising car ownership in the developing world, but the bottom line is that the industry is likely to shrink down to a size which the earth's lithium supply can handle.

swimfar 12y ago
If we assume that people continue to drive the same number of miles per year, the robotaxi concept won't actually reduce the number of cars being produced* . (number of cars produced/year=number of people * average number of miles driven per (person* year) * (1/average life of a car in miles) ). But it would do two other things. It would reduce the number of cars in existence at any given time potentially freeing up space (garages, driveways, parking garages, street parking, etc.) for other things. Also, cars would wear out faster (in time) which means you would shift the average age of cars on the road down. So on average it would also increase the safety and efficiency of cars on the road as well. Imagine 10 people who drive 10k miles per year who own cars that last 100k miles (just for the sake of simplicity). Right now, those people would each own one car for 10 years. In the system you suggest they would all share one car which would be replaced every year. So they would be driving a (technologically) new car every year. Of course this assumes that none of them ever want/need to drive at the same time. Perfect usage like that is not likely, but you can see that shared usage would still have this effect (even if it is not as large). * Neglecting the damage to cars which is not due to driving wear, e.g. corrosion. Taking this into account we would expect to see a reduction in the production due to being able to get more miles out of a car before it "can't" be driven anymore.
- nkoren 12y ago
  Your formula is incorrect; time is more of a factor than mileage, when it comes to vehicle deterioration. This is why you routinely see taxis with more than 300,000 miles on their engines. Furthermore, automation itself will reduce wear-and-tear. I worked on the driverless pod system at Heathrow Terminal 5. One of the things we found was that wear-and-tear on the system was almost negligible -- probably less than 10% of what you would see in a human-driven vehicle. This was partially due to the fact that it was driving on a smoother surface than an ordinary roadway -- but also due to the extremely conservative and consistent acceleration/braking behaviour which the vehicles achieved, which put much less stress on many parts of the system. Although those are essentially hand-built prototype vehicles, I expect them to last ~400,000 miles before requiring significant refurbishment. Based on these observations,I feel quite comfortable predicting a dramatic decline in the rate of vehicle sales within the next several decades.

by nkoren 12y ago

swimfar 12y ago

If we assume that people continue to drive the same number of miles per year, the robotaxi concept won't actually reduce the number of cars being produced* . (number of cars produced/year=number of people * average number of miles driven per (person* year) * (1/average life of a car in miles) ). But it would do two other things. It would reduce the number of cars in existence at any given time potentially freeing up space (garages, driveways, parking garages, street parking, etc.) for other things. Also, cars would wear out faster (in time) which means you would shift the average age of cars on the road down. So on average it would also increase the safety and efficiency of cars on the road as well. Imagine 10 people who drive 10k miles per year who own cars that last 100k miles (just for the sake of simplicity). Right now, those people would each own one car for 10 years. In the system you suggest they would all share one car which would be replaced every year. So they would be driving a (technologically) new car every year. Of course this assumes that none of them ever want/need to drive at the same time. Perfect usage like that is not likely, but you can see that shared usage would still have this effect (even if it is not as large). * Neglecting the damage to cars which is not due to driving wear, e.g. corrosion. Taking this into account we would expect to see a reduction in the production due to being able to get more miles out of a car before it "can't" be driven anymore.

nkoren 12y ago
Your formula is incorrect; time is more of a factor than mileage, when it comes to vehicle deterioration. This is why you routinely see taxis with more than 300,000 miles on their engines. Furthermore, automation itself will reduce wear-and-tear. I worked on the driverless pod system at Heathrow Terminal 5. One of the things we found was that wear-and-tear on the system was almost negligible -- probably less than 10% of what you would see in a human-driven vehicle. This was partially due to the fact that it was driving on a smoother surface than an ordinary roadway -- but also due to the extremely conservative and consistent acceleration/braking behaviour which the vehicles achieved, which put much less stress on many parts of the system. Although those are essentially hand-built prototype vehicles, I expect them to last ~400,000 miles before requiring significant refurbishment. Based on these observations,I feel quite comfortable predicting a dramatic decline in the rate of vehicle sales within the next several decades.