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Re:The Netherlands is making moves to ban all non-electric v... by mantas on Monday April 18, 2016 @09:49AM (#11519833)
> Electric vehicles – including self-driving cars – are clearly the future

Partially off-topic, but it feels very weird when people put electric and self-driving cars into the same basket. Those are 2 different problems. There're electric cars which are not self driving. There're cars aiming to be self-driving, that are not electric.

Re:The Netherlands is making moves to ban all non-electric v... by cyphax on Monday April 18, 2016 @10:28AM (#11520125)
I noticed that too. It's maybe because both are some pretty big advances that are happening somewhat simultaneously?

I seriously doubt this whole thing will actually happen. The plan was made by one of the governing parties but the other party in the coalition thinks the plan is idiotic and I'm not sure there's enough backing for it overall. I for one hope to be able to drive an electric vehicle in a few years (self-driving or not; but the Dutch road network probably really need this kind of solution to the congestion problems it has) but there are all kinds of smaller hurdles. It still takes a bit too long to charge mid-trip but I'm not entirely sure I could charge at home, not having a driveway (and probably be disallowed by regulation to just leaving a cable laying across the street where I park). Or at work, actually we don't really have any kind of parking provided by my employer (which is the government in this case). I dunno if I have to add 20 minutes a day to my commute to charge the batteries. Some also say our electric network cannot really handle the shift from fossil fuels to electricity in terms of bandwidth. Again, I hope to see this happen but we need a whole lot of people on the bandwagon or it's not going to happen in the time period the plan describes (but I do think it'll happen sooner or later).

Re:The Netherlands is making moves to ban all non-electric v... by infogulch on Monday April 18, 2016 @11:14AM (#11520537)
Electric vehicles are many many times simpler than their gas-powered cousins. This simplicity is passed onto the self-driving computer as fewer variables.

Also, the primary downsides to electric vehicles -- longer refuel times, reduced range -- are mostly irrelevant when a computer is doing it by itself. Nobody cares if their self-driving taxi spends 10 minutes recharging itself between every pickup.

Re:The Netherlands is making moves to ban all non-electric v... by arijun on Monday April 18, 2016 @11:42AM (#11520790)
> Electric vehicles are many times simpler than their gas-powered cousins

What does engine complexity have to do with driving complexity? I imagine that a computer would drive a car using interfaces analogous to those we use; namely gas, brake, steer (and I guess a shifter to put it in drive).

Re:The Netherlands is making moves to ban all non-electric v... by ZeroGravitas on Monday April 18, 2016 @03:25PM (#11522472)
Electric cars can react to changing inputs faster than gas powered cars. They can also have two, three or even four, independent motors driving the wheels. This makes it much easier for a computer to achieve high performance, though the difference may not be noticeable until you hit a gravel patch and attempt to recover at high speed.
Re:The Netherlands is making moves to ban all non-electric v... by rlidwka on Monday April 18, 2016 @01:03PM (#11521412)
Potentially, higher acceleration/deceleration would allow a computer to use simpler collision prevention algorithms. Also, there is no shifter there.
Re:The Netherlands is making moves to ban all non-electric v... by djschnei on Monday April 18, 2016 @01:21PM (#11521558)
improved acceleration/deceleration aren't givens for electric vehicles. You shouldn't let the Teslas cloud your perception here - usually they are slower than their internal combustion peers. Also, no reason for a self driving algorithm to worry about shifting. In an automatic car do you worry about shifting?
Re:The Netherlands is making moves to ban all non-electric v... by schwap on Monday April 18, 2016 @12:57PM (#11521354)
> Electric vehicles are many many times simpler than their gas-powered cousins. This simplicity is passed onto the self-driving computer as fewer variables.

From the self-driving computer's perspective they are the same. Running the engine by computer is a solved problem.

Re:The Netherlands is making moves to ban all non-electric v... by fullshark on Monday April 18, 2016 @01:03PM (#11521407)
They are the two advances people are excited by. Putting both in the first sentence is a way to lure people in to read the article.
Re:The Netherlands is making moves to ban all non-electric v... by sonnyp on Monday April 18, 2016 @10:27AM (#11520116)
One could argue that self-driving cars potentially consume less energy by driving more efficiently than humans.
Re:The Netherlands is making moves to ban all non-electric v... by Houshalter on Monday April 18, 2016 @10:54AM (#11520356)
Self driving cars will almost certainly use much more energy than regular cars. It will reduce the cost of shipping by a lot, increasing the amount of things which are shipped. It will reduce the price of taxis a lot, so people will drive more. And it will make long commutes and road trips much more convenient.
Re:The Netherlands is making moves to ban all non-electric v... by toomuchtodo on Monday April 18, 2016 @11:54AM (#11520889)
Maybe, but you're still limited by atoms not occupying the same physical space at the same time ("traffic", "congestion", etc).

There's limited road to use, so you'll still hit finite limits; if limits are reached, congestion charges will be used to bring demand inline with roadway supply.

Re:The Netherlands is making moves to ban all non-electric v... by Heliosmaster on Monday April 18, 2016 @12:10PM (#11520998)
ideally the throughput of highway would be increasing with self-driving vehicles: no need for start/stopping when they can drive at optimum total velocity.
Re:The Netherlands is making moves to ban all non-electric v... by agumonkey on Monday April 18, 2016 @01:01PM (#11521390)
Yes but the swinging hours pattern will melt since cars are now decoupled from humans cycle. Freeing a lot of pseudo-space.
Re:The Netherlands is making moves to ban all non-electric v... by vkou on Monday April 18, 2016 @10:30AM (#11520146)
We already have an energy-saving self-driving mechanism - cruise control (and obeying the speed limit.)

I drive a hybrid. Except for a few parts of my commute, cruise control and slow acceleration push me from 42 mpg to 50 mpg on my commute.

Re:The Netherlands is making moves to ban all non-electric v... by vonmoltke on Monday April 18, 2016 @10:43AM (#11520253)
> We already have an energy-saving self-driving mechanism - ... (and obeying the speed limit.)

Obeying the speed limit is irrelevant; the actual speed is. A given car at a given speed consumes the same amount of fuel per unit distance regardless of what the speed limit is.

All the data indicating that "speeding wastes fuel" is basically just proving that fuel economy is a function of engine power output.

Re:The Netherlands is making moves to ban all non-electric v... by Houshalter on Monday April 18, 2016 @10:59AM (#11520399)
Actually it's more to do with air resistance. It increases exponentially at higher speeds. You also don't burn less by driving really slow, since the engine burns some amount of fuel just by running at any speed. 40 mph is the sweet spot, supposedly.

Driving at the speed limit will definitely save you more fuel than speeding.

Re:The Netherlands is making moves to ban all non-electric v... by vonmoltke on Monday April 18, 2016 @11:41AM (#11520777)
> Actually it's more to do with air resistance. It increases exponentially at higher speeds. You also don't burn less by driving really slow, since the engine burns some amount of fuel just by running at any speed. 40 mph is the sweet spot, supposedly.

Actually, the sweet spot is dependent on the design and condition of the car. I'm not sure where exactly it is, but I think you are right that it is usually around 40.

> Driving at the speed limit will definitely save you more fuel than speeding.

How does a number on a sign affect how much fuel I'm burning? If, as you indicated, the sweet spot for my car is 40 but the speed limit is 30, how am I saving fuel by going 30 instead of 40? What if the speed limit is 65? If they drop it to 60 am I suddenly using more fuel? If they increase it to 70 can I now go faster without using more? The speed limit is totally irrelevant to fuel consumption.

Re:The Netherlands is making moves to ban all non-electric v... by Houshalter on Monday April 18, 2016 @11:48AM (#11520848)
Of course it depends on the design of the car, but 40 is an average.

>How does a number on a sign affect how much fuel I'm burning?

I never claimed that it would. I said "Driving at the speed limit will definitely save you more fuel than speeding.", which is definitely true. If you speed you are going faster and using more fuel.

Re:The Netherlands is making moves to ban all non-electric v... by vonmoltke on Monday April 18, 2016 @12:19PM (#11521061)
> I never claimed that it would. I said "Driving at the speed limit will definitely save you more fuel than speeding.", which is definitely true. If you speed you are going faster and using more fuel.

That statement has nothing to do with the speed limit, though. It may be trivially true, but adding the speed limit ties an irrelevant variable to it. Speed limit is a semi-arbitrary number that has nothing to do with how much fuel a car uses and how efficiently it uses it.

Re:The Netherlands is making moves to ban all non-electric v... by phpnode on Monday April 18, 2016 @01:09PM (#11521449)
The implication is that driving over the speed limit is likely, on average, to be less fuel efficient than obeying it. Due to the laws of human nature, very few people drive significantly below the speed limit, and very few people prioritise their fuel economy over everything else so this translates to a reasonable guideline.
Re:The Netherlands is making moves to ban all non-electric v... by tremon on Monday April 18, 2016 @04:06PM (#11522776)
The implication is that driving over the speed limit is likely, on average, to be less fuel efficient than obeying it.

Not necessarily, because of gear changes. Not all cars can use 5th gear in a 50km/h zone, so they'll drive in 4th gear. It seems likely that doing 60km/h in 5th gear is more efficient than 50km/h in 4th gear.

Re:The Netherlands is making moves to ban all non-electric v... by Alupis on Monday April 18, 2016 @01:32PM (#11521652)
> Of course it depends on the design of the car, but 40 is an average.

Funny, I had always heard 55 MPH was the "sweet spot".

Drag Coefficient will be dramatically different on all car models.

Driving slower can have as dramatic of an impact on MPG as driving too fast. Your engine has to work quite hard to keep the car moving in both cases. Once up to a cruising speed, your engine will have to work less hard (and burn less gas) to maintain momentum. This is why your foot is not on the accelerator pedal harder while cruising on the highway when compared to driving on the streets. This is also part of the reason overdrive gears work (<1:1 ratio).

From a dead-stop, you dump the most unburned hydrocarbons (as a bunch of fuel is dumped into the chamber suddenly). So, constant highway driving will be more efficient than a slower city-street driver.

Re:The Netherlands is making moves to ban all non-electric v... by pflanze on Monday April 18, 2016 @12:52PM (#11521313)
> increases exponentially at higher speeds

Exponential with regards of the speed? That sounds odd. So I looked it up:

https://en.wikipedia.org/wiki/Drag_equation

    F = (1/2) * \rho * u^2 * C * A

    F: drag force
    u: flow velocity relative to the object
So, quadratically.
Re:The Netherlands is making moves to ban all non-electric v... by Retric on Monday April 18, 2016 @10:46AM (#11520286)
You're ignoring breaking. If you go significantly faster than the speed limit your far more likely to break at highway speeds.

Further, IC cars often get better fuel efficiency by mixing slow acceleration periods at optimum RPM and coasting. (Car engines get ~10-30 efficiency based on usage.) You can do this manually, but it's hard.

However, air resistance is going to be the dominate factor at high speeds.

Re:The Netherlands is making moves to ban all non-electric v... by vonmoltke on Monday April 18, 2016 @12:12PM (#11521014)
> You're ignoring breaking. If you go significantly faster than the speed limit your far more likely to break at highway speeds.

I'm not ignoring braking. Aggressive driving wastes a lot of fuel, but aggressive driving happens regardless of the posted speed limit. In fact, that rapid acceleration-brake cycle is more likely to happen when the flow of traffic is below the speed limit.

> Further, IC cars often get better fuel efficiency by mixing slow acceleration periods at optimum RPM and coasting. (Car engines get ~10-30 efficiency based on usage.) You can do this manually, but it's hard.

I don't think it's hard. It just requires paying attention to the traffic around you.

Re:The Netherlands is making moves to ban all non-electric v... by sliverstorm on Monday April 18, 2016 @02:54PM (#11522264)
I think you're being deliberately obtuse. For 99% of people, obeying the speed limit will result in slowing down, which is what your parent was alluding to.