Hacker News new | past | comments | ask | show | jobs | submit login

It can certainly cause light issues, but I'm not sure why it would cause _congestion_?



More people in a smaller area?

Congestion doesn't just refer to car traffic

Edit: think about crowded grocery stores and restaurants. Think community spaces like parks and libraries being packed all the time. Think about never being able to stop and get a coffee without waiting in a long line. Congestion


> Think community spaces like parks and libraries being packed all the time.

They aren't, with dense housing there is so much room for parks that they are everywhere. I live in such a place, you go out and you mostly hear birds chirping, not people, it is a cheap suburb with high rise apartments next to public transit and everything you need in walkable distance including hospital and government services and hardware stores.

Dense housing means there is more room for everything else, not less, so everything is less crowded. Birds singing outside of my windows is the main noise pollution where I live.


That's only true if we hold the population constant, and get everyone to scrunch together onto smaller lots built taller.

The main aim of density is to turn cities of a million into cities of ten million, not to just stick with a million and have birds chirping in parks everywhere you go.


No, the aim is to have that one million people occupy a smaller area, so that there's more space for parks, open space, farms, etc.


Sorry, which density advocacy groups have this nice idea as their literal goal?

Density is the population of a metropolitan area divided by its total area. Not population divided by the footprint area of residential lots. Density advocacy is all about accommodating population influx; it is really burgeoning population advocacy.


Every group I know of that actually advocates for density does have this as their goal. It is a bit odd that the external reputation is that they do not, to the point that parallel orgs sometimes appear advocating for pretty much the same things but "with more emphasis on livability" or similar.


Really? Is this documented somewhere? What is the typical proposal for how they plan to keep the population constant, after creating all that space? I've not heard of this. It's always about how many more millions of people could live here if we rearranged things.

I've never heard of a density advocacy group being opposed to population growth. Density advocacy is practically synonymous with at least acceptance (if not advocacy) of urban population growth. Population growth is in fact like a sacred cow. You must never blame any urban problems on population growth; the cause is always not enough vertical build.

Is there any example of a density anywhere going on record that the metropolis in this local neck of the woods should somehow say no to more people, rather than building more?


> What is the typical proposal for how they plan to keep the population constant, after creating all that space?

Have other metropolitan areas do the same so there is no net migration.

> Is there any example of a density anywhere going on record that the metropolis in this local neck of the woods should somehow say no to more people, rather than building more?

There is a difference between refusing new people and having population growth as a goal. People exist, they have to live somewhere, increasing density increases the housing stock and gives them somewhere to live.

If one city is hostile to giving them somewhere to live and another isn't, people might move from the hostile place to the amiable place. But the solution to this is obviously to make the other city less hostile, not to make sure that all cities are maximally hostile.


paris proper is already one of the densest areas in the world (and definitely in europe). when i lived there i wouldn't have noticed any problems with crowded grocery stores or community spaces compared to the comparatively low-density city i currently live in.

there definitely were a lot more people in the streets, other cities feel deserted in comparison.


> i wouldn't have noticed any problems with crowded grocery stores or community spaces

There are so many of them. Every block seemed to have grocers and a small park.

Where I am it’s a massive supermarket every 5km, not a small one every 200m. You can shop different when it’s less hassle to go.


Delivery also lets you have more smaller stores carrying the 80% you need regularly, and the 20% that is less common can come via delivery in a day or two.


This seems like a fundamentally suburban perspective, and I don't mean that to be an insult, it's just what all of my small home town family members and friends think, and it overwhelmingly and ironically relates to the real traffic congestion they actually experience coupled with the hypothetical imagined congestion they pre-emptively avoid exposure to by driving instead of getting on the train.

Not that there's _no_ foot traffic congestion or lines, but it's the same thing that happens in a case where there's only one Starbucks in a sprawling suburb or business district at lunch time.

A high density area is likewise it's own complex economy and system that seeks balance, when there's too many people in one area, you just go somewhere else or enjoy or compete with it. That's partly why Tokyo is simultaneously the most populated city on earth and one of the most quiet, clean, and least congested places I've visited.

In my sparsely populated city that sprawls, it's extremely noisy, dusty, time consuming to get around, the infrastructure is failing, and I rarely bump into anyone I know, because people are only visible at the beginning and end of their journey. Meanwhile here in Vancouver I often run into people I know multiple times per day because we're in the same spaces, or I can go somewhere else and not see anyone just like any other place.


>Tokyo is simultaneously the most populated city on earth and one of the most quiet, clean, and least congested places I've visited.

Sorry, no this is culture. The same virtues exist in Japanese suburbs, nothing to do with a city.


"Partly why". It's just an example, I'm sure other cities are more hectic. I didn't get the impression that Japanese suburbs were particularly different than North American ones in terms of volume levels or how uninteresting they are.

It seems to me that it's mainly cars and a scarcity of places to be that make cities horrible and congested. More pollution, more noise, less space.


> Edit: think about crowded grocery stores and restaurants. Think community spaces like parks and libraries being packed all the time. Think about never being able to stop and get a coffee without waiting in a long line.

Have you lived (rather than just visited; extremely tourist-oriented areas can be broken in the way you describe, because all of the tourists stay there) in a large dense city? I'm sure there are exceptions (chiefly places with broken zoning/planning) but _in general_, if there's enough traffic for the cafe that people have to wait in long lines, _someone will open a cafe_. To the point where "there are a silly number of cafes" is a complaint people sometimes make about such cities.

Same goes for the rest of it, of course, but "dense cities have insufficient cafe provision" is a particularly bizarre take.

In Dublin (not a massively dense city; it's about a quarter the density of Paris, or a little less than San Francisco), we had an almost complete collapse of construction following the financial crisis, only really resuming around 2014. One interesting consequence of this was _fake cafes_. When you build an apartment block, you probably want to do _something_ with the ground floor, and in urban apartment blocks it'll rarely be used for housing; instead it'll be used for retail units. So if you build the apartment block, and then the next day the construction industry collapses and there's an unfinished site next door for five years, what do you do with the retail units? You don't want them to look derelict, so you put in fake cafes! (Via images on the windows).

Growth has since resumed, the unfinished sites are gone, and the fake cafes have become manifest, adding to the bafflingly large number of cafes in the city.


> think about crowded grocery stores and restaurants. Think community spaces like parks and libraries being packed all the time. Think about never being able to stop and get a coffee without waiting in a long line. Congestion

That depends on supply and demand, not simply demand. More people attract, open and staff more shops, etc. It's easier to find a restaurant in a major city than a quiet rural town.


Mixed use zoning solves that as businesses (grocery stores, cafes, pharmacies, etc.) are able to locate closer to people.


I would imagine that the answer would be to open more shops. Obviously, to avoid a NYC-like situation, you would have to bust the CRE cartels that keep retail square-footage absurdly expensive. Parks and libraries are harder... though building taller does tend to allow for more open land space.


I guess one person's congestion is another person's lively and bustling city?


> think about crowded grocery stores and restaurants. Think community spaces like parks and libraries being packed all the time. Think about never being able to stop and get a coffee without waiting in a long line.

It also changes behaviour. People are under stress all the time. It's not a nice or natural way to live. But it is easier to govern people.


I really think people underestimate how much of this is down to _taste_. Personally I've lived in pretty sparse suburbs of Dublin (by European standards, anyway; think semi-detached houses, as far as the eye can see), in the city centre, and in dense inner suburbs (walking distance to the centre, generally terraced houses and apartment buildings). I wouldn't consider going back to an outer suburb, never mind a rural area. But I know some people who live in the middle of nowhere and love it! Couldn't do it, myself.


...This is the state of people living under car-dependency, not dense urbanism supported by public transit and walkable areas. Car noises stress people out, make them irritable, impact their health. Driving in traffic makes people angry/furious/insane (literally - it is not sane to pull a gun on someone driving past you but it happens). Prioritizing parking and roads is a colossal misuse of land which causes crowded public spaces; imagine if every parking lot was an additional market or park.


But, they are closing roads making them one way etc, that creates the traffic problem. It's bad governance - creating pain to allow government to administer the preordained 'solution' - no cars!

Moving to car less city is the goal, but, as others note, the infrastructure is not there. So you're just pushing cars out... with no real answers being provided.

How is that good government?

And the roads you call mismanagement are already there! Removing them, deteriorating their use is what's new...


This has nothing to do with my comment or what I was replying to, which was a comment about crowded public spaces.


> People are under stress all the time. It's not a nice or natural way to live

You might be thinking of packed slums in a developing country.

> But it is easier to govern people.

Ah yes, like the French, a famously docile people who never, ever rise up against their government.


We just like to be vocal and share our disagreements publicly. It used to force a bit of honesty (it's not working much right now)


It causes congestion if the city refuses to invest in public transportation - which is more a problem in US cities - though some European cities could be behind on keeping up with changes to different degrees


Congestion is a problem even in cities with excellent public transportation. Have you ever been on the Tokyo subway at 8:30 am?


Yes, it always a balance of factors in the system, but what you're talking about is a higher threshold of capacity already. They've built up to higher rise density in Tokyo and are already managing much higher people movement in core higher density areas than the edges of Paris.


Oh, right, I see, yeah. Would not generally be an issue in Paris, I would've thought, at least not towards the centre.


You'd be mistaken. Public transit is extremely crowded in the centre during rush hour.

For example, two regional lines (RER B and D) need to share a tunnel in the middle of the city. They've been investigating digging another one for a long time, but, AFAIK. they haven't found an economical way of doing so. The solution is to try to move people to other lines, but those are already very crowded and I'm not aware of any project to build a new line inside of the city limits.


Ultimately you have more people coming and going from each building, which means more people on the streets, and more demand for all utilities and public services. Building up doesn't build out those other things. That's why you have things like Air Rights in NYC to limit building.


People aren't very noisy. Cars are


I don't know... I lived in Barcelona for two years recently and had pretty bad luck. In addition to one-off incidents, some consistent noise issues we had:

- The Pakistani restaurant below our apartment would regularly host receptions/weddings until 2-3am. The sendoff typically involved groups of 20-30 people banging large drums loudly and singing as the happy couple walked out and were driven away.

- We had a neighborhood drunk who frequently (multiple times a week) would wander down the street singing Flamenco-style ballads about his unfortunate love life. My assumption was that the ex he was singing to lived on the street? Anyway, he had quite a voice and was great at projecting.

- The building behind us was shorter than ours and our rear balcony faced their rooftop. In the summer one of the apartments there would semi-regularly hold parties until 1am.

Cars were an occasional issue too, but people were a much bigger problem in that particular neighborhood. That said, I've also lived in dense neighborhoods with none of those problems, so maybe better norms/regulations are the answer... but existing noise ordinances in the US are rarely enforced.

Beyond the noise issues though I did enjoy the convenience/amenities that a dense neighborhood provides!


Theoretically all those interactions breach the social contract and could be acted upon by making complaints. However, someone loudly driving a multi-ton car down your road is always "okay".

Also... I live in a low-density urban neighborhood currently and it's the loudest place I've ever lived. Mostly it's road noise, but also one of my neighbors parties 12+ hours every weekend playing music very loudly. Some people are just loud, but cars make everybody loud.


> However, someone loudly driving a multi-ton car down your road is always "okay".

Cars with fart pipes installed are the same kind of violation. Modern cars with functioning mufflers or electric powertrains... aren't actually that loud.


> Modern cars with functioning mufflers or electric powertrains... aren't actually that loud.

Until their tires hit asphalt. Cars have to go very slowly for the engine to be louder than the tires, and that noise is a function of weight, and electric cars are heavier than equivalent ICE cars.


Most of the sound from a modern car with a functioning muffler is wind noise. You can barely hear the tires unless you're standing right next to it.

"Electric cars are heavier" is some silly nonsense where people went looking for something to complain about. You can make an electric car as light as you want, with the trade off that it implies making the battery smaller and reducing range. But the Model 3 has a ~300 mile range and weighs the same as the average car.


> Most of the sound from a modern car with a functioning muffler is wind noise

What? Like wind hitting the extremely aerodynamic surface of the car designed specifically not to catch the wind? I have never heard or read this in my life - it is widely known that tires-on-pavement is the biggest contributor of car noise. That roar you hear standing a quarter mile from a busy highway is not wind, it's the tires.

> "Electric cars are heavier" is some silly nonsense where people went looking for something to complain about. You can make an electric car as light as you want, with the trade off that it implies making the battery smaller and reducing range.

Again, this contradicts everything I've read and/or is just willfully ignorant. You can't make EVs superlight by stripping down the body, for example. The battery is the heavy part and while they may get more mass-efficient over time EVs are now and for the foreseeable future strictly heavier than same-size ICE cars.

EVs aren't the savior of the environment, public transit is. EVs are better than ICE cars in most ways, but for noise all cars are a problem and EVs are worse.


> What? Like wind hitting the extremely aerodynamic surface of the car designed specifically not to catch the wind?

Like the sound of a hundred cubic feet of metal displacing the air at 40 MPH and leaving vacuum in its wake, yeah. That they're designed to be aerodynamic is the reason they're not that loud.

> That roar you hear standing a quarter mile from a busy highway is not wind, it's the tires.

Now you're talking about highways. People don't typically drive at highway speeds on city streets.

> Again, this contradicts everything I've read and/or is just willfully ignorant.

People have agendas. They need some reason for electric cars to be bad.

The Model 3 weighs around 4000 pounds, as do the Ford Taurus, Chevy Camaro and BMW 3 series, all vehicles of approximately the same size.

Some cars are lighter than this. Some are heavier. In general the existing production electric cars tend to be on the heavier side because premium car buyers prefer longer range to less weight, and that's the trade off. But there is nothing inherently requiring that, and in fact electric cars with smaller/lighter batteries would be cheaper, so that's likely to be what happens as more affordable electric cars become available.

> You can't make EVs superlight by stripping down the body, for example.

If you have an electric car with a 1500 pound battery and a 300 mile range, there is a fairly obvious way to make one that has a 100 mile range and weighs 1000 pounds less, and it doesn't require changing the size of the cabin. You might even get more than 100 miles of range by doing this, because now the car weighs 1000 pounds less and requires less energy to accelerate.

> EVs aren't the savior of the environment, public transit is.

Public transit is inapplicable to any place without enough density to support it. More than two thirds of Americans live in suburban or rural areas. We could build millions of new high density housing units and the majority would still live in suburban and rural areas -- and that's unlikely to change, because housing is scarce and only a fraction of those units would be converted specifically because of how many more units you can put on a lot for high density housing. If you build 20 units to a lot you could double the number of urban housing units while only reducing the number of suburban/rural units by 2.5%.

All of the people who live there will continue to need cars.


> Now you're talking about highways. People don't typically drive at highway speeds on city streets.

That was an illustrative example. Tires typically overtakes engine noise at about 25mph. That's city street speeds. (In most car-dependent cities 40-50 is also typical city street speed.) Again, this is why tires are the majority of car noise. When you hear a car pass by on a non-highway road, you're mostly hearing tires.

If wind is a serious factor either you need to publish your secret findings or link me to some research I'm not finding.


> Tires typically overtakes engine noise at about 25mph.

This is like saying "a person typically travels at 30MPH". It doesn't mean anything. An off-road truck with knobby tires is going to have more tire noise than a sedan with snow tires which will have more than the same sedan with low rolling resistance tires. An 80s muscle car will have more engine noise than a modern 4-cylinder sedan which will have more than an electric vehicle. A gasoline vehicle under acceleration (as in stop-and-go city traffic) will have much more engine noise at a given speed. Tire noise is affected by the roadway material in addition to the vehicle. Tire noise in a 4000 pound electric car might overtake "engine noise" at a lower speed than it does for a 4000 pound V8, but that's because it's quieter, not louder.

> When you hear a car pass by on a non-highway road, you're mostly hearing tires.

Then why does it make a "whoosh" sound?

> If wind is a serious factor either you need to publish your secret findings or link me to some research I'm not finding.

I suspect the problem here is that the studies are so old. Here's the relevant sentence from the Wikipedia article called Road Noise:

> Noise of rolling tires driving on pavement is found to be the biggest contributor of highway noise and increases with higher vehicle speeds.

For this sentence it has three citations. One discusses the effects of road material on tire noise and not tire noise relative to other noise, another lumps tire noise and aerodynamic noise into the same category. The third, which is presumably where it got the premise, is from 1973, when cars commonly used bias-ply tires, which are much louder.

But let's not lose track of the thread here. The premise is that electric cars would be louder. A Model 3 is ~4000 pounds, the same as a Ford Taurus, so that's not going to be louder. Some cars are lighter -- a Honda Accord is in the same class and is ~3200 pounds, only 80% as much. But then it has a gasoline engine, which is louder than an electric motor. Does the 20% weight difference cause more noise than the gasoline engine vs. the electric motor? Somebody would need a dB meter to even answer it, and that's rather the point. Either way the difference is going to be small and people are just looking for something to complain about.


> This is like saying "a person typically travels at 30MPH". It doesn't mean anything.

No. It's very different. It's more like saying "a person is usually about 5'7"." It is obvious there are difference, but it's not something that varies minute by minute, and the range of differences is not stated. There's definitely not cars moving 40+ mph without making a lot of tire noise.

You're right those aren't good citations, I looked at it earlier myself and didn't like them, but I didn't go through the work of finding better ones. But seriously, can you find a single study saying wind is a dominant factor in road noise? Again, I've never heard anyone claim that.

> Then why does it make a "whoosh" sound?

Because, that's the sound it makes.

> But let's not lose track of the thread here.

This started because you claimed modern cars are not noisy except for those with modified exhaust pipes. I'm saying cars are fucking loud, all of them. Electric cars are also loud and do not solve for the problem of road noise at all. The fact that we're trying to figure out if wind or tires is the source of the noise that we both acknowledge is quite noticeable makes no difference except to support my actual point, that cars are loud.


> There's definitely not cars moving 40+ mph without making a lot of tire noise.

Based on what? A car with low resistance tires on concrete isn't going to make a lot of tire noise even at fairly high speeds.

> But seriously, can you find a single study saying wind is a dominant factor in road noise?

The one lumping tire noise and aerodynamic noise together is obviously contemplating that aerodynamic noise is a thing.

> Because, that's the sound it makes.

Tires make a rumbly sound, when you can hear them, as for example with the types of tires that make more tire noise.

> The fact that we're trying to figure out if wind or tires is the source of the noise that we both acknowledge is quite noticeable makes no difference except to support my actual point, that cars are loud.

There is a difference between something not being absolutely perfectly silent and something emitting a loud noise. Road noise for most modern cars at city speeds isn't loud. Exhaust noise for cars with negligently or intentionally defective mufflers is loud.


> Road noise for most modern cars at city speeds isn't loud.

If you can hear it and you're not next to the road, that's too loud. It's noise pollution. You can personally draw an arbitrary line anywhere you want to determine what counts as "loud", but the actual phenomenon is that cars make an amount of noise that is detrimental to our health, sanity, and wildlife.


As you note, no two dense neighborhoods are the same. Those experiences would be rare in Tokyo or Kuala Lumpur. I would say that cultural norms dominate density when it comes to explaining late-night partying.


recently moved half a mile further out from city center and can attest to all of this. Hookah bar in my case was blaring music at 1AM. People in various states of inebriation shouting to each other outside my bedroom window.

There's less car traffic too but that was such a background noise that I hardly noticed it. Though truthfully the first week or so at the new place I was conscious of it's absence.


NYC started making certain streets pedestrian-only during COVID. The silence was astonishing.


Same thing on snow days in Manhattan. It's eerily quiet


I have never met a car that had a fight with her spouse that woke up the whole block at 3AM


Cars get into wrecks all the time :) Seriously though we just normalise it. If there is a car accident on your street everyone is awake. How about cop cars and ambulances racing by sirens blaring at all hours. People blast horns way louder than anyone will shout.


You need better walls, aren't there standards that apartment walls need to be sound proof?


Remember that in the US at least, many dense buildings are incredibly old, from before soundproofing and such was really common.

Living in a 1900s building in Brooklyn is vastly different from living in a 2020 building in Manhattan.


My early 1910s Manhattan building was fantastically quiet, with very thick walls. The only noise I ever heard was floor noise directly above me, never to the sides.

I'm guessing mid-1900s to early 2000s buildings are the problematic ones.


The higher the density, the more vehicles get in each others way.

If your reply is that the vehicles are not needed because everyone can just walk: it takes more energy and more carbon emissions to walk a mile than it takes to drive a vehicle a mile -- and that's before we get to transporting things other than people. (Growing food is very energy intensive; walking burns food.)


A 155lb human burns 177kcal when walking at 2.5mph[1], so that's 71kcal per mile

There are 340kcal in 100g of wholemeal wheat flour[2], so walking one mile takes around 21g of wheat

Wheat flour creates carbon emissions of 0.80 kg CO₂e/kg [3], so walking one mile creates carbon emissions of 170 g CO₂e

Driving a vehicle powered by gasoline produces tailpipe emissions of around 400g per mile [4]

[1] https://www.healthline.com/health/calories-burned-walking#Wa... [2] https://knowledge4policy.ec.europa.eu/health-promotion-knowl... [3] https://apps.carboncloud.com/climatehub/product-reports/id/9... [4] https://www.epa.gov/greenvehicles/greenhouse-gas-emissions-t...


However if the calories from your walk come from beef ...

100g of beef gives you 217 kcal [1], so you need 33g of beef for your walk

Carbon cost for beef is 99.48 kg CO₂e/kg [2]

So walking one mile fueled by beef creates ~3.3kg of carbon emissions, over 8 times what would be emitted if you drove

[1] https://www.healthline.com/nutrition/foods/beef#nutrition [2] https://www.statista.com/statistics/1201677/greenhouse-gas-e...


Oh and it turns out the carbon footprint for beef varies significantly by where the beef is raised. Average carbon footprint per 1kg of beef in the EU is 22.1 kg CO₂e [1], so if you're in the EU your beef-fueled 1 mile walk emits ~730g of CO₂e, a little under twice what you'd have emitted if you drove

[1] https://www.thebeefsite.com/news/33676/uk-beef-carbon-footpr...


If I'm reading this right it's not quite apples for apples, as it's comparing the cost to create and move the beef, but doesn't consider the cost to create the car, only the movement of the car.


Except the only people who eat that much beef are certainly not walking anywhere so it’s a fun “statistic” that has no basis in reality.


A car driver could easily eat the same amount of food as a walker, the extra calories would be stored as fat. This also ignores upfront CO2 output from assembling and delivering the car and increased CO2 output from maintaining car infrastructure vs. pedestrian infrastructure. Not to mention numerous other externalities.


Don't forget that the person would be burning calories even if they weren't walking.


The figure for calories consumed when walking is excess calories consumed (compared to sitting still)


Are you sure? It doesn't say that.


I am sure. Think about it for a minute and you'll see why


I don't. Could you explain what you mean?

Here's what I found: the formula given in the article is "calories burned = BMR x METs/24 x hour"

But the METs for lying quietly is 1. The author certainly forgot to subtract 1 from METs in that equation, and could easily have also forgotten to do so when calculating the given numbers.

https://pacompendium.com/inactivity/


It just wouldn't make any sense to tell people "you burn X calories when walking/running/whatever for an hour" if they had to subtract their base metabolic rate from the number.


I agree it should state the excess calories burned. I think the author probably misunderstood the formula.


"it takes more energy and more carbon emissions to walk a mile than it takes to drive a vehicle a mile"

I've never heard that before, can you expand on that?


I wouldnt be completely surprised if it were true, though I lack the background and willpower to try to get an actual answer lol.

My thought process is that food also implies some level of driving (delivering pesticides/fertilizer, driving crops away), the fertilizers are fossil-fuel derived, and if you count the sun it takes to grow crops to eat (or worse, as feed for meat).

The whole chain is pretty inefficient, too. Crops are pretty good at converting sunlight to stored energy, but animals and us are bad at retrieving that stored energy. The losses compound if we're eating meat.

Walking isn't a particularly efficient method of movement either, to my understanding.

The energy gets a bit spurious though. One could argue that if we're going to count sunlight going into the crops, we should do the same for the sunlight that raised the dinos so they could become oil.

I also would wager that starts and stops would impact this heavily. The human weighs a lot less so they can accelerate/decelerate much cheaper. The car would have a better edge on a long, straight mile with no stops.


A human walking is absurdly efficient, as anyone who's ever tried to outrun a bad diet can tell you. Running or walking a mile burns ~100 extra calories relative to sitting on your couch. Unless you're putting active effort into not doing so, most diets fluctuate by far more than that.


Sure, but it is also true that food that is healthy for people is an absurdly expensive form of energy compared to gasoline.


If we make free the largest costs of gas, greenhouse gas emissions.


Even if we count the cost of the co2 emissions: it probably takes more petroleum products to grow the food for the walking delivery workers than it takes to fuel the delivery truck.


I don't remember where I heard it, only that it was an expert on agriculture saying it.

The easiest way to see that it is plausible is to note that only 400 years ago, something like 90% of all human labor went into growing food, which is the way agricultural societies had always been everywhere. The way society was able reduce that to the 5% or so it is today was to use fossil fuels. The first big reduction came with the mechanization of textile production, freeing the food-growers from the need to make their own yarn and weave it into fabric to make clothes with. The tractor was of course also responsible for a drastic reduction in human labor as input to food-growing. Also, the replacement of horses with trucks for transportation of food from the farm to the nearest rail head or port or river (and transportation of inputs like fertilizer to the farm) meant that the food-growers could concentrate on growing food for people now that horses were much less needed.

It's not just the extra calories needed to walk as opposed to rest or to watch television: it's the fact that a single person in a delivery truck can do the work of a dozen people who have to do the deliveries on foot, and keeping one person alive and productive costs only one twelfth as much as keeping a dozen alive and productive -- even if no one walks anywhere or does any exercise. Sometimes for example in order to remain alive and productive, one of the dozen will need to visit a doctor. The doctor requires food to stay alive and productive. Doctors don't live forever and so need to be replaced, and that is an expensive process in part because medical students need food and lots of other energy-requiring things to stay alive and able to learn (and to grow from babies to people mature enough to go to medical school).

My guess is that that analysis continues to hold even if the dozen delivery workers can take public transportation as well as walk although maybe we have to replace "dozen" with "six".

I'm not saying that restricting vehicles in Paris is a bad move: I'm just saying that the effects on, e.g., carbon emission is not obviously good and that the planners who chose (e.g., https://en.wikipedia.org/wiki/Haussmann%27s_renovation_of_Pa...) to devote a large fraction of the area of cities to make it easy for vehicle traffic to flow were not just stupid benighted fools or evil people bent on making life worse for everyone.


When people suggest that we reduce the number of cars driven, they are generally not talking about reducing commercial delivery vehicles [1]. Obviously our civilization depends on moving essential stuff around, and we need to do continue doing that, albeit with a electrified fleet of trucks/vans. The problem is with private cars, electric or internal combustion.

[1] Excluding Uber style car-based food delivery services.


OK, but some people here are asserting that the more urban density, the better, and neglecting to consider that if the density gets high enough, the commercial delivery vehicles are stuck in traffic most of the time or the residents of the city refrain from buying things that would enhance their lives if it weren't so expensive or tedious to move things around the city.


Which is why if you've ever lived far outside the city, you're tired of people from the city coming out to visit you to buy all the stuff they can't get in the city.

Oh, no, it's the other way round, mostly. It's easier to deliver a quantity and variety of goods to a dense area than the sticks. Which is why "go shopping" is a suggestion for people going to NYC, not Tucson.


In deciding between a city where personal vehicles are banned or discouraged and a city where they are allowed, noting the virtues of cities over rural areas is relevant how?


High density is what enables mass rail transportation, which is much more efficient than personal vehicles.


Mass rail is most efficient when it's full.

https://afdc.energy.gov/conserve/public_transportation.html - a full car gets amazingly close to a average train (USA).

And this is seen in that trains are most common where they can be mostly full.

What's scary about that is how quickly busses just get outclassed - they have to be as big as their biggest loads, but they're usually empty.


How often do you see a full car? Average vehicle occupancy is 1.67, and has been for years.


Quite often! But usually in the mirror/kid cam, because I'm driving the family somewhere.


> it takes more energy and more carbon emissions to walk a mile than it takes to drive a vehicle a mile

Do you have a source for this? Sounds questionable.


It's false. People will not go into suspend mode when not walking; they still burn calories. A very large person would burn about 130 calories walking a mile. i.e. one large latte. And most people who are this large are not at risk of a caloric deficit by burning an extra 130 calories.


Humans are INSANELY efficient at walking. That's why walking and running are terrible ways to lose weight.



Yeah well I'm not exactly 4000 pounds or going 60mph hah


I agree that OP's assertion sounds dubious (especially considering the entire supply chain) but calories are a measure of energy, not CO2. You need to know the rate of CO2 emitted per kcal.


I'm not claiming that the CO2 exhaled by people is relevant. I'm claiming that growing food requires significant energy inputs unless you want to go back to the world where most human labor went into growing food.


A single mile, no.

100 miles? That seems very likely. That happens far quicker for the energy leaking heat machine sitting in the seat.

So, while maybe the theme of the statement is correct?


It's simply not.


The problem that this is the wrong measure to use emissions per mile, when it's really about emissions per trip.

A car flying down the freeway uses less emissions per mile, but if one is traveling 50 miles versus just walking to down the block the former is using a lot more emissions even if it is more efficient per mile.


This is simply abject nonsense. I know the research you obliquely referenced and it assumes you specifically fuel that movement by eating beef burgers. And even that's on shaky ground.

You can use your eyes to instantly observe that car drivers are not reducing their caloric intake to compensate for the fact that they "save" that energy by not walking.




Guidelines | FAQ | Lists | API | Security | Legal | Apply to YC | Contact

Search: