While there may be more cars doing return journeys I suspect there will not be the same level of traffic jams as the cars return.
1. Most outward trips would be chained: drop 1, drop 2, drop 3, return to base; rather than: drop 1, return to base, drop 2, return to base, drop 3, return to base. As would most return journeys.
2. The roads would be clearer in cities due to fewer parked cars. In some cases there would be an extra lane now available.
3. Cars could still have multiple bases, especially if they are shared. Car parks could be re-utilised as a stop-off points where empty cars could 'swap out' and remove themselves from the system briefly.
4. Chains could be linked: do the early run, do the late run. Do the Smiths; do the Joneses.
5. Empty cars with no urgent pick-up could wait for the roads to clear before embarking on a return journey.
6. Would anyone care if a car returns to base slowly if there wasn't an urgent passenger waiting?
Cars could be more efficiently used and that would certainly imply that the fewer number of cars in existence would be being used for more trips throughout the day.
I admit that it will be hard to remove the rush-hour problem entirely without a significant amount of car-sharing. However with a fully self-driving system cars could do clever passenger shares (and/or mid-route swaps). Passengers would be free to only car-share within their sex / family / workplace / social networks etc.
1. Most outward trips would be chained: drop 1, drop 2, drop 3, return to base; rather than: drop 1, return to base, drop 2, return to base, drop 3, return to base. As would most return journeys.
2. The roads would be clearer in cities due to fewer parked cars. In some cases there would be an extra lane now available.
3. Cars could still have multiple bases, especially if they are shared. Car parks could be re-utilised as a stop-off points where empty cars could 'swap out' and remove themselves from the system briefly.
4. Chains could be linked: do the early run, do the late run. Do the Smiths; do the Joneses.
5. Empty cars with no urgent pick-up could wait for the roads to clear before embarking on a return journey.
6. Would anyone care if a car returns to base slowly if there wasn't an urgent passenger waiting?
Cars could be more efficiently used and that would certainly imply that the fewer number of cars in existence would be being used for more trips throughout the day.
I admit that it will be hard to remove the rush-hour problem entirely without a significant amount of car-sharing. However with a fully self-driving system cars could do clever passenger shares (and/or mid-route swaps). Passengers would be free to only car-share within their sex / family / workplace / social networks etc.