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> All the environmental damage. Environmental damage is the argument against traffic calming measures. Vehicles are most efficient traveling at a consistent, r
by AnthonyMouse 2y ago
> All the environmental damage.
Environmental damage is the argument against traffic calming measures. Vehicles are most efficient traveling at a consistent, relatively high speed. The reason the national speed limit was historically set at 55MPH was that was the approximate speed at which aerodynamic losses overcome mechanical losses from low gearing at low speeds, i.e. it was the speed that vehicles of the time were most fuel efficient. Modern vehicles have even better aerodynamics. Moreover, fuel efficiency for electric vehicles is essentially moot, because they have built-in storage that can be charged from intermittent renewable sources during times of oversupply when the power is "free".
Conversely, traffic calming generally results in vehicle speed changes as motorists slow down and then speed back up again in response to obstructions or areas with intentionally low visibility, which not only wastes fuel by operating vehicles below their optimal speed, it results in braking and acceleration that increases brake dust and tire wear.
Environmentally, the optimal road is flat and straight with no traffic control devices or other reasons for vehicles to change speed, i.e. a highway.
- pfg_ 2y agoEnvironmentally, the optimal road is the road with no cars on it. Ideally, traffic calming is paired with cities where things are put closer together and where walking, biking, and transit are the most viable options for most trips. Traffic calming a road in a suburb a mile from the nearest store might help with safety, but people will still use cars to get everywhere.
- AnthonyMouse 2y ago> Environmentally, the optimal road is the road with no cars on it. But then why is there even a road there? How to reduce the amount of travel required and how to most efficiently get from A to B are two different issues. Doing the former is good, but it requires things like new higher density housing construction, which takes a long time and is not going to cause most of the existing homes in the suburbs to cease to exist under any plausible expectation. One of the reasons for this is that high density doesn't require much land; if you build 20 units to a lot then you could double the existing suburban housing stock as high density units, but you'd have only bulldozed 5% of them to do it, so the other 95% would still exist. This would reduce housing costs but you'd still have someone living in most of those existing homes, which are in places it's not viable to walk or use mass transit. And then you might want to ask a question like "how do we make transportation more efficient in the short term, i.e. on a 5-10 year timescale"? To which the answer is things like "make new cars electric" and "optimize high-traffic roads to maximize the efficiency of existing vehicles".
- dghlsakjg 2y agoThis assumes that cars are the only way to get around. A bus that starts and stops as it goes through traffic calming with 100 people on it will make an absolute joke of the efficiency of even the most fuel efficient of cars. In areas where transit is given its own lane, or is a train, the time efficiency is much better as well. Plus if you give buses their own lanes you can remove traffic calming measures for them and give them signal priority, thus making them even more efficient from a resource, and time perspective.
- AnthonyMouse 2y ago> This assumes that cars are the only way to get around. Which is true in many cases, and would take decades of construction to do anything about, e.g. because people would have to move out of the suburbs or else at least one end of the trip will require a car, which would require massive long-term new housing construction in urban areas and has no short-term solution. > A bus that starts and stops as it goes through traffic calming with 100 people on it will make an absolute joke of the efficiency of even the most fuel efficient of cars. A city bus will get around 5MPG. The most efficient cars get more than 50MPG, so a city bus isn't even as fuel efficient as the cars until it's carrying more than 10 passengers. In theory they can carry 30-40 passengers, but generally in practice they don't, and in theory that 50+MPG car can carry five or more passengers too. > In areas where transit is given its own lane, or is a train, the time efficiency is much better as well. "In areas where the time efficiency of car traffic is purposely degraded, car traffic has lower time efficiency" is kind of tautological, but that's a silly argument for doing it, especially when the proposed alternative isn't available, e.g. because one of the endpoints is in the suburbs and the bus doesn't go there. > Plus if you give buses their own lanes you can remove traffic calming measures for them and give them signal priority, thus making them even more efficient from a resource, and time perspective. It's kind of odd that the same people who talk about wasted space from parking want to allocate entire bus lanes worth of space for a vehicle that only uses them 0.2% of the time. Also, what are you proposing here? 50+MPH buses traveling next to bike lanes and pedestrians? It would have to be even higher than that, because the bus is constantly starting and stopping to pick up passengers (and is then stationary for several seconds), so to achieve an average speed of e.g. 30MPH, its cruising speed would have to be above 60MPH, which is not only dangerous if adjacent to pedestrians, it's extremely inefficient as you're repeatedly accelerating a huge bus to highway speeds and then back again. When the alternative is a car traveling a constant 60MPH on a highway, the bus compares unfavorably in terms of both time and fuel efficiency.
- oblio 2y agoLOL, ever heard of particulates from road wear and tire wear? Guess how the production of those scales with higher speeds? > Vehicles are most efficient traveling at a consistent, relatively high speed. Guess what, that's changing with EVs. Hybrid or not. > Environmentally, the optimal road is flat and straight with no traffic control devices or other reasons for vehicles to change speed, i.e. a highway. Awesome, put those where nowhere lives.
- AnthonyMouse 2y ago> LOL, ever heard of particulates from road wear and tire wear? Guess how the production of those scales with higher speeds? I didn't have to guess because I looked it up. Turns out it's much more proportional to acceleration/deceleration than absolute speed. > Guess what, that's changing with EVs. Hybrid or not. But EVs can charge from renewable sources and then they don't have any fuel-related emissions. > Awesome, put those where nowhere lives. Roads are used for going from where people live to where they want to go.
- oblio 2y ago> But EVs can charge from renewable sources and then they don't have any fuel-related emissions. That was my point. Maybe the paragraph order was confusing. > Roads are used for going from where people live to where they want to go. They (or stroads, or highways) shouldn't be used in place of streets. A city should have the minimal set of roads to get the job done, everything else should be traffic calmed streets.
- blackeyeblitzar 2y ago> Guess how the production of those scales with higher speeds? I am guessing you don’t know yourself which is why you’re posing questions as an argument. > Guess what, that's changing with EVs. Hybrid or not. It’s not changing. Consistency of speed is important no matter what. Regenerative braking is imperfect.
- oblio 2y ago1. I do know, higher speeds, higher particulate production from road and break wear. 2. Yes, it is changing, LOL. And this is not about breaks. I was talking about power consumption. EV power consumption, unlike ICEs, is linear. So EV are obviously more power efficient at lower speeds. Besides the particulate generation aspect outlined before.