The "externality" most discussed is generally carbon emissions, for obvious reasons. It used to be particulates, for local health reasons. Noise rarely gets a mention.
But, if someone from an all electric future was dropped off in 2016 i think they'd really notice noise above everything else. Traffic noise in cities is a massive "silent" irritant. Even outside of cities, it's amazing how far you need to be from a road to hear unadulterated wilderness. Off-road, dirt bikes, quads, water craft and such can really impact enjoyment of outdoor recreational places.
I don't think the psychological impacts of this are fully understood, but it is understood that they aren't trivial. The whole world will get so much more peaceful with combustion engines out of the picture.
Air travel is the one area where reducing noise would carry an obvious economic benefit to airlines. Unfortunately it's the one of hardest ones to solve.
Unfortunately electric cars won't solve the noise problem. The graph on http://www.leiserstrassenverkehr.bayern.de/laerm/entstehung/ (a German government website) compares the engine noise ("Antriebsgeräusch") with the tire noise ("Rollgeräusch") for different speeds ("Gesamtgeräusch" means "total noise"). The yellow line is for trucks, the blue lines for cars.
As you can see at a speed of 40 kph (25 mph) a car's tire noise is already higher than the engine noise and at even higher speed the engine noise doesn't really matter anymore. So even if your electric car engine is absolute silent, the total noise at speeds above 30 mph won't be all that different.
The only real solution is electric cars plus significantly reduced speed limits.
That must only be comparing standard passenger sedans. I live at the intersection of a busy street and your typical motorized car is barely audible through the window. Cars are not the problem.
The vehicles that shake the apartment are pickup trucks (low rumble), sport cars (high pitched tear), transport trucks (big rumble), and motorcycles (little explosions that set off car alarms). Electric container trucks would be a huge win for ambient noise.
I also live close to a very busy intersection and I have to agree with you. I'll add though that when you leave your window open then general car noise definitely becomes a problem, and also wanted to add that I for myself would ban honking, it's one of the worst feelings in the world to be woken up at 8 in the morning by guys or ladies honking their car for 5 seconds or more.
I'm also living at such a busy street. It's a big difference compared to a house in a quiet street without any traffic.
Keeping the window open during night is a huge problem now. In my old home I did that always, now I have to fight against the heat in the rooms or the noise.
Also looking a movie with open windows is not much fun. The cars stop at the traffic lights, the engines start crying when the light turns green and I missed part of a dialog...
That beeing said, choose your home carefully. Especially when you lived before in a quiet neighborhood.
I lived in an intersection like you and now I have lots of health issues and I'm extra sensitive to smog..it makes life much harder and shortens life-span. All I can say is that it's not worth to live in a place like that...move somewhere else if you can
Yellow lines are trucks and blue lines are cars. The graph actually shows that until around 60 km/h it's mostly the motor noise that's a problem with trucks.
That analysis is missing a important factors. Engine output varies greatly, and they get a lot louder when the vehicle is accelerating hard or going up a hill. And average noise is not very important, peak noise is far more so.
I don't doubt that tire noise dominates on average, but engine noise from big trucks is far louder at peak. At least for the roads near my house, typical traffic is a steady ignorable hum, but when big trucks go by uphill or start moving from a stoplight, they make so much noise I can barely hear myself think.
Cars are similar, usually much smaller in magnitude. Every so often you get some silly person who thinks a bad muffler makes his car fast and compete with the big trucks.
Electrification may not bring down average noise levels much, but it'll still make it a lot more pleasant to be near a busy road.
Engines have a different sound profile that makes comparing the sounds produced a little more complex. Further, on a highway the worst offenders have much worse engine noise than average.
Concrete is the worst, you can hear the roar from concrete road miles away.
Porous tarmac is much quieter and much safer, in S Wales UK I remember vividly a trial many years ago on a section of the M4.
In very heavy rain, on the normal tarmac - much standing water, aquaplaning risk, low visibility, huge spray, then onto the porous section - zero spray, no standing water, was amazing like night and day.
They never implemented though, double the cost, so not worth the many lives it would save!
Almost all roads in the Netherlands are made with the porous tarmac, it solves many problems, but it will not last as long as the non porous variant and is indeed more expensive...
Thanks for sharing this graph! I've often wondered about tire vs. engine noise, and this answers all my questions in one succinct graph.
From my point of view, this data makes me optimistic, because I'm most bothered by noise when I'm walking beside the road on city streets, which are below 50km/h, and the graph promises a noticeable improvement in that area.
Doesn't the graph on that site show that electric trucks would be a huge win for lower noise in the city? I would be interested in the standard deviations of these line plots, because I would guess that the engine noise varies much more depending on the acceleration of the truck. I am not that much annoyed by a truck driving with constant speed, but much more annoyed by a truck which is heavily accelerating. And maybe 9 out of 10 trucks passing by are just driving with constant speed but the 10th will be the one which is annoying because it is accelerating.
Electric scooters are almost completely silent (at 40km/h). So I'd say there's a lot of potential for lower noise tires. I guess at the moment there's just no optimization towards low noise profile. And I assume it'll be with trade-offs.
On wet streets the noise from the tires is also a lot louder. Another thing we're completely used to. But once you pay attention to this, you realize just how much louder it actually is.
Electric scooters have a much smaller tire surface area, which is probably a big part of it. Wet roads, too, caused by that -- more area to slap water.
I don't even hear the tires on the little Google Pods they're driving around Mountain View these days, which seems to have little bitty tires like a smart (wise for efficiency), but the drive is quite audible. As an aside, it's oddly futuristic, though; I think they did that on purpose because when it goes by I get confused and think I'm in Star Trek for a minute. It genuinely sounds like background foley in Hollywood future movies, and I'm not sure I really mind it.
I'd laugh if Google put all this money and time into self-driving cars, a big executive-involved project at a behemoth, and in the end the engineers gave it the Star Trek background-whirr noise on purpose.
I live in the country and my house is about 100-feet off a rural highway with a 65-mph speed limit. Being Texas, most folks are going a bit faster.
One of my neighbors has a Tesla. It's no quieter at these speeds than the numerous diesel pickups that inhabit these parts -- the tire noise is amazingly loud. Luckily this road isn't very heavily traveled or I'd be tempted to build a berm or other noise abatement obstruction.
Or better engineering for the tires, emphasizing also their sound profiles. Tire tech has advanced a lot in the past 20 years, I imagine that adding another coordinate for optimization would be doable, albeit hard.
>>The only real solution is electric cars plus significantly reduced speed limits.
Which isn't a solution as it would be like saying "the only real solution is no automobile (cars/vehicles)", because people will want ever more speeds.
So I guess, we must look for other better solutions. Somewhere I read that some chemistry researchers (AFAIK at Purdue university) are trying to improve the road building material/tyre surface material such that the noise caused by the impact of tyres on the roads is reduced. They claim that the noise caused by the impact of the speeding tyres on the road-surface is a very large noise cause.
there were some experiments years ago that don't seem to have gone anywhere because of costs, where old tires were ground up and added into the asphalt for new roads - at a HUGE difference.
I think no one has really been making an effort in this area lately, but doesn't make it impossible.
I don't know german, does that account for road type? I know the tire noise in my car is freaking horrible on the lousy plain concrete highway, but drops off nicely as soon as I hit any nicer material.
Why boo? Reduced speed maps to vastly reduced pedestrian death and injury, encourages increased bicycle road share, and allows reduced lane sizes which increases the usable land in urban environments.
The speeds in the article are in km/h, not miles/h. Residential zones in Germany are 30 km/h, larger inner-city roads are usually 50 km/h, so this very much applies to cities too.
So what was that thing about wanting to add artificial noise to electric cars for safety reasons because you normally can't hear them coming? Was that just bogus stuff from someone?
This - after leaving the city to live by the sea I hugely notice all traffic noise when I come back to London - it's just never ending. Much of London is blighted by aircraft noise too - again I never gave it much thought and believed my London garden was tranquil and calm, but in my new place I can easily go hours without being disturbed. And when a plane does fly over it's so much higher - I can't believe West London puts up with it.
That said - I now really notice the diesel smell and the fumes in central London. I used to cycle through it every day and couldn't see what the problem was, but as soon as I get off the tube I can smell the stink of smoke lorries and buses.
> And when a plane does fly over it's so much higher - I can't believe West London puts up with it.
I lived at various times in Fulham, Putney and Richmond, and worked directly under the flight path.
What choice do most people have? All the MPs in the area are against adding a runway at Heathrow, as are all past and current mayors of London, but expanding the airport still hasn't been ruled out.
Anyone unfamiliar could look here, and see the trail of planes approaching LHR over London: https://www.flightradar24.com/51.51,-0.19/11 (flights are restricted at night, which will be about 2200-0400 UTC)
I lived in Fulham for 2 years and on the one or two days that Heathrow was shut down there was a strange unsettling silence. It would usually take a good 15 minutes to realize there wasn't a plane flying overhead every 90 seconds.
In Hounslow, around 1000ft to under 200ft as they cross the perimeter of the airport.
Many of these planes are large jets, 747s and similar. You can usually see the next plane before the first has disappeared from view, and hear both. Between 270,000 and 700,000 people are affected by the noise, depending who you believe.
After renting a house directly under the flight path as a student, I tried never to do so again. Places under the flightpath are slightly cheaper, although anyone new to the area probably doesn't realise the extent of the problem until it's too late.
I didn't think about it for my employer though, and worked for several years directly on the approach path. On some days it wasn't possible to hold a conversation outside. I felt it led to constant stress. On a rare day with no noise (e.g. after the volcanic eruption in Iceland) everyone seemed so happy and relaxed — as if it were the first day of nice weather in spring after a month of rain.
The airport publish this map: http://myneighbourhood.bksv.com/lhr/ which shows that in many areas, there is noise (by some definition) for more than half of the day. (Make sure to tick landing approaches at the bottom.)
I used to live under the approach/departure paths to one of the runways at MSP.
Landings are for all intents and purposes silent. I could sit on the deck and watch airliners landing all day long because they are completely throttled back at that point.
Takeoff, OTOH is a whole other issue. By the time they got over my house in south Minneapolis, they were already turning away (noise abatement procedures I guess), and you got used to it after a while but it was still grating. I learned pretty quick which days to keep the windows closed :-(
> Landings are for all intents and purposes silent
What altitude were the planes?
Over Fulham (in London), it's about 3000ft and they're audible as a background rumble. They're so frequent the noise never really stops.
By Richmond at 1800ft it's not possible to have a British-volume conversation outside (Americans might be OK…). By Hounslow (down to ~200ft as they cross the airport boundary) it's uncomfortable.
Heathrow's own numbers say 700,000 Londoners have >55dBA noise from flights. (This is mostly landings, as prevailing winds mean take-off is usually away from London.)
I went to a college which was a five minute car ride from an airport. An airport which is used for mixed civilian/military use. So we had fighter jets flying over campus almost every day along with the regular coterie of commercial jetliners.
It was really bothersome at first but eventually your mind can block it out. Now I live next to a rail track and the train noises don't bother me at all (although they are definitely much less severe).
YMMV though. It probably helped my brain was younger then.
I remember noticing it when I first moved there but you get used to it very quickly. I was always amused at how much my family commented on it when they came to visit because I didn't really register it anymore.
Maybe Heathrow Airport could follow the example of John Wayne Airport, which is in the middle of Orange County, California. Airplanes have to land in a corkscrew pattern and take off at very sharp angles in order to minimize the noise disturbance in the surrounding suburbs.
True - we don't have a lot of choice sadly (other than to live east) but the blight it adds to some stunning areas in London and to the south west is insane. We wouldn't put up with trains being that noisy!
If you are a bright young thing then the air in Central London matters not, neither does the noise or the ever present danger of getting run over. But, once you have seen the bright lights and spent some time working somewhere 'trendy', then the things like air quality, local community, noise, access to green space and less overcrowding really does matter, even if you are not with a family.
However, some people are more sensitive to noise (and pollution) than others. Peace and quiet is actually a nightmare to some, not something to be cherished. I would prefer to hear the wind breezing through the trees and bird song, most people would prefer to blot this out with music or TV. It does concern me that I share this planet with so many people that care so little about such things!!! What hope is there for a better world? How does anyone concentrate at the top of their faculties when their senses are just polluted with noise?
Regarding West London, this is the sweet spot for London. There is better air around Bushey Park, Richmond Park, Wimbledon Common and the bits of green in between. At the top of somewhere like Kingston Hill the air is not the same as down in the West End.
Due to prevailing wind directions, East London is not as good as the West. The transport links are not as good either, whether that be road or public transport.
Back to the plot of the article, I don't see why a hybrid variant can't be done with trucks to take them from the town centre to the ring road. In that way the engine can operate at peak efficiency on trunk roads and motorways and the electric drive train can deliver efficiencies in the city or town.
I am sure that the likes of Mercedes have considered this but there must be some economic reasons why this has not happened. I am amazed that basic stop-start technology has taken so long to happen. This is a no-brainer with no technical difficulties and an obvious saving to all. But we waited decades for that, probably phased out by lead in petrol...
> I now really notice the diesel smell and the fumes in central London.
Completely agree, the noise is pretty bad, that said you can tune it out or sound insulate your home. I find the fumes from traffic the real pain point of city living.
From what I understand ozone and particles with sizes of 2.5 microns or less (PM2.5) are a key part of it and are damaging to our bodies. Some of these particles are small enough to cross the air/blood barrier in our lungs and disrupt cell function. At a minimum you'll have increased inflammation of the respiratory passages which makes things like pollen and pet allergies wrose.
I'd recommend anyone living in a city to invest in a good air purifier from BlueAir or IQAir (if you can afford it).
It's amazing how bad particulate counts (which inflame our respiratory passages) get on certain days of the year.
Few great sites to track pollution in your area are:
When I flew into Heathrow last year, I was amazed by how visible the pollution was- over central London, there were no clouds (there were clouds around the outskirts) but this vague, blue haze was quite noticeable.
Although compared to Shanghai, London is really clean, if you live in Shanghai you keep your windows permanently shut and run an air purifier 24/7: http://aqicn.org/city/shanghai/
> I'd recommend anyone living in a city to invest in a good air purifier from BlueAir or IQAir (if you can afford it).
I'm on a balcony right up against national forest land as I'm typing this. My typing is the loudest thing I hear. If I stop typing, I don't just hear birds and wind, I hear insects. Lots of them. When I lived in NYC, it was incredibly loud, I was very aware of this, there's nothing at all silent about it. I think after a number of years people aren't merely used to it being noisy, they have some amount of permanent hearing damage, they're just not phased by delivery trucks banging around, sirens blaring, wheels on tracks squealing. There is certainly a lot of room for improvement when it comes to noise.
This will help reduce engine noise, as well as stink and heat from the truck's exhaust, both of which will be nice. Buses are also loud in city streets and both trucks and buses use braking systems that are fairly loud. I don't know what braking systems these will use but I'm guessing it still needs to be pretty heavy duty and could still be loud.
Regenerative brakes typically can't handle hard braking braking. In Teslas for example it's paired with regular disc brakes, but those brakes are rated for 100,000 miles because of the reduced wear. I would expect this truck to have regular (loud) air brakes installed, but they might be used less often if the driver brakes early & gently enough for regen to do the whole job.
Regenerative brakes can handle hard braking, but you need some place to dump the energy. Locomotives use big resistive iron grids and fans for this. Those are in the "ears" seen on the sides of modern Diesel-electric locomotives. Electric cars usually don't have that.
A heavy truck, though, probably should. Dynamic braking is great for going down long grades, because the motors and resistors can handle the load continuously without overheating. Some power can go back into the battery, but the battery may not be able to take it all, due to charging rate limitations.
Presumably if the motors are beefy enough to accelerate that 20-ton truck, they're beefy-enough to regeneratively brake it as well, right? I mean, still not as quickly as friction brakes can, but at a comparable level to passenger car regenerative braking.
Having daily driven a dual-motor electric car, two turbodiesel cars (both modern and classic), and a modern Honda V6, I can tell you that the electric car is significantly quieter, especially at lower speeds and when accelerating, both inside and outside the car.
You're right that tire noise is significant, though, and that electric cars (and trucks and buses!) are not completely silent. They are definitely MUCH quieter than the drum-drum-drum of an accelerating diesel truck engine, though!
Now, if only they could get rid of that annoying beep-beep-beep a reversing truck makes...
The reversing beep-beep ain't going to go any time soon -- it's a audio warning to prevent workers being crushed under reversing trucks.
(It might go if and when reversing cameras, which are now standard on automobiles, become standard on trucks ... but there are headaches implicit in adding them to articulated lorries: what about side blind-spots? What about the trailer, as opposed to the tractor? What if a trailer-camera isn't hooked up -- should it be impossible to reverse an electric tractor if it has a trailer hook-up but no signal from the camera on the trailer?)
As someone with construction taking place next door to me I really wish they would start getting rid of the beeping in more places. I'm pessimistic that it will happen in my area anytime soon though.
The beep-beep could be a lot quieter in general, just needs to have something so it's adaptive to the current ambient noise level. At the moment it has to be loud enough for any situation.
Well look I'm a big Tesla fan, too. When it comes for those _outside_ the vehicle the OP is right. Where I live I get engaged by Model Ss all the time in city traffic, either on bike or on foot. For me, there is no noticeable difference between a _modern_ car and a Tesla when it comes to the noise level. Perhaps it's bias as I might expect the Tesla to be more quiet than it is, but anyway that's my perception.
Here's my experience outside the vehicle - I live about two miles from Tesla HQ in an area where electric vehicles of all types are common, and bike frequently in close proximity to motor vehicles.
You're right that there is still noise, particularly from the tires, and that they are actually surprisingly loud if you are expecting silence (mostly tire noise, particularly when turning, plus a little high-pitched whine).
But when accelerating from a stop, compared to a gas car or especially a truck, the difference is noticeable. No 'vroom' or 'rattle' or 'rumble.' Trucks in particular can be window-shakingly loud. Priuses are also nice and quiet...
All true. Also important to note that it would be dangerous if the car was completely silent. Even if the car is autonomous and has a crazy smart AI, there can be accidents if people outside don't notice the car. Also, any car will spin up dust from the road that people outside breath up. I think, the only way to truly increase quality of life for pedestrian and bikers is to have zones and streets which are banned for cars, like many European city centers.
I'm surprised that many areas in Seattle don't ban cars during business hours.
There are many places in Europe that do that, except that they make just enough exceptions for this or that car that it still makes it hard to be a pedestrian.
At low speeds, it's not sedan cars that are a problem: even at idle, trucks and large SUVs are very loud, and accelerating from e.g. traffic lights they really roar. For busy city centers, quieting the trucks and buses (and goddam noisy-on-purpose motorcycles!) will make a big difference.
By my experience, IC engines are only quiet when the car is coasting, but not when it is accelerating or has to go uphill. Having compared the driving noises of electrical and ICE cars driving past me, the noise reduction is quite significant. Even more, when accelerating at traffic lights, or when cranking the car.
Dirt bikes and quads have pretty loud exhausts. And people with 4wd trucks like to put aftermarket exhaust on them because they think they get better performance.
Dirt bikes, or their barely civilized moped cousins, are a significant component of traffic in some countries.
Many small island communities are plagued by these nasty little things. It's two-strokes buzzing by all day long, and each one of them is louder than twenty cars.
One reason: It's much easier to carry a five gallon jerry-can of gas or diesel with you when you head out into the boondocks, just in case, as opposed to spare battery packs sufficient to get you back out to civilization.
However: plug-in hybrids would be an option. (Diesel pack and fuel tank for off-grid use, electric motor and battery good for ~20-50km as well for use on short trips about town/daily commutes.)
Most of a second drivetrain, system to make them work together, a bunch of batteries and the associated weight makes a lot of sense in a harsh environment, not to mention the increased cost for something that will get the crap beaten out of it.
There's a reason oil field trucks tend to be the most minimal trim available. More stuff -> more stuff to break -> more complicated service -> waste of money. Automatic windows are a convenient but hard to justify when they cost more up front and cause more downtime over the life of the vehicle. Ditto for most other luxury features.
You know what sucks, having a Prius that won't use its electric powertrain because the software is trying to protect the integrated A/C compressor from damage because a rock kicked up by another vehicle was the straw that broke the camels back and causes the condenser to leak out refrigerant. Now imagine not being able to use half the powertrain of a pickup you're trying to do work in. See the problem? Sure you could do a different A/c system but you're probably giving up some other important performance metric (like fuel economy) or you could let it ruin the compressor (but then the customer will complain or you'll waste money replacing compressors under warranty)
GMC made a hybrid pickup. It was cool because it could be used as a power source to run tools at a jobsite. It didn't sell. They canned it.
I'm on the waiting list for a Model 3 and plan on getting and e-bike some day http://www.ktm.com/gb/e-ride/ I own a loud KTM 300 2 stroke and a diesel truck. Tho I'll probably never sell my Harley evo, loud pipe save lives ;-)
The tires noise probably has to do with the road and tire quality. I remember walking on a quiet street in the suburbs and being very surprised by a seeing a Prius driving past me as I didnt hear it coming at all.
You can't rev an electric car when impatient. You don't have to shift gears. When using engine braking it's quietly absorbing energy, not letting out an angry BRAAPPPPP.
If you're deaf, sure, combustion engines are quiet. Otherwise they're often quite loud.
Noise is the main reason I'd like to leave the city to live in the country. To me it just feels insane how little of a concern this is to most people. Cities could be really nice places to live if they didn't allow cars in them, but instead they're ruined by pollution (noise and emissions).
> But, if someone from an all electric future was dropped off in 2016 i think they'd really notice noise above everything else.
Given the move to regulate hybrid and electric vehicles so that they make as much noise as traditional ICE vehicles (notionally, as a safety measure of visually-handicapped pedestrians), I'm not sure that that's the case.
So true, the only time I ever experienced true silence, was off piste skiing in St Anton, Austria.
Stopping for a rest in a deserted valley, it was so beautiful and the silence was so peaceful, I was mesmerised until the silence was broken by a bird singing a few miles away. An incredible experience I'll never forget.
apparently, such noise also affect the biosphere. Birds and animals change behavior based on this noise. Its one reason why traveling in developing/under-developed countries feels so different. The noise levels are very different.
Particulates and stuff that forms ozone are both still a big deal. The reason that the SF Bay area air-quality district funds free electricity at public car chargers is to reduce smog in the Bay area.
Indeed. For example, the VW emissions scandal was entirely about particulates and similar. The fix will likely increase CO2 emissions. Local pollution and CO2 emissions are somewhat at odds with each other, especially for diesels.
But, if someone from an all electric future was dropped off in 2016 i think they'd really notice noise above everything else. Traffic noise in cities is a massive "silent" irritant. Even outside of cities, it's amazing how far you need to be from a road to hear unadulterated wilderness. Off-road, dirt bikes, quads, water craft and such can really impact enjoyment of outdoor recreational places.
I don't think the psychological impacts of this are fully understood, but it is understood that they aren't trivial. The whole world will get so much more peaceful with combustion engines out of the picture.
Air travel is the one area where reducing noise would carry an obvious economic benefit to airlines. Unfortunately it's the one of hardest ones to solve.