World's first electrified road for charging vehicles opens in Sweden | Hacker News Reader

World's first electrified road for charging vehicles opens in Sweden

theguardian.com

162 pointsrb80898 comments

I hope Sweden and Germany can make a common DIN Deutche industri normen standard for charging electric vehicles on roads. There would be an added benefit if we could build rail tracks among the electric guidance line. Rail tracks to lower the rolling resistance, metal on metal vs rubber on asphalt. We would then have a hybrid car rail track which should make it easy for autonomous driving. The aim would to bring down the total co2 emissions of transportation. Building both in ground and above ground electrification of cars would be the best system as then cars can charge during good weather conditions and trucks can always charge even during winter time. A system with electric guidance in the ground is a bit vulnerable to snow during winter times.

Here is another more rail like track which can be used by trucks but not by cars. https://www.scania.com/group/en/worlds-first-electric-road-o...

Rolling resistance coefficient c of rail c=0.001, dirty tram rails c=0.005, car c=0.02. Ie rails resistance is at least 25 times lower than rubber on asphalt 0.005/0.02. https://en.wikipedia.org/wiki/Rolling_resistance https://www.engineeringtoolbox.com/rolling-friction-resistan...

Let's just only have train tracks? We can still have electric trucks for the last mile, but then they won't need electrified roads.

Long-distance goods transport with trucks is such a ridiculous concept, it's really time we just face it: it only ever made sense because the state funds the roads and road repair from general taxation, we have ridiculous subsidies for the fossil fuels that make it run and trains had the misfortune to be invented such a long time ago that the government has suffocated the industry.

Rolling resistance is somewhat of a rounding error, by the way. The big killer is aerodynamics: the power needed to push air out of the way increases quadratically with speed. But there is a cheat code: if you make the vehicle longer or add something to the back, it can ride in the slipstream. Only you can't make trucks very long at all because they need to work on public roads. Trains on the other hand can be made ridiculously long, saving massively on energy - multiple miles of wagons if you so wish.

Moving goods from the train to the truck is not a negligible cost. Also, you have to move lots of things in batch with the train, which makes product and supply chains unless nimble. Perishable agriculture products, for one thing, benefit greatly from truck transport.

A nimble supply chain, or "just in time" as they call it, is a hack large companies use to shift quantities from one column of their quarterly reports to another that the stock market looks more favourably upon. Analysts can't very well quantify the risk of a JIT supply chain but they know cash flow over finished goods.

That isn't true. It means you need less storage space, and you need less capital tied up in parts you aren't using. It also means your cabbages don't rot.

> Moving goods from the train to the truck is not a negligible cost.

Really? I was under the impression that this was one of the primary benefits of standard shipping containers.

That goods transfer costs would be negligible?

Between shipping modes, yes. Hence the name "Intermodal Container".

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

Yes. Unloading stuff from a container is not a negligible cost, but transferring the whole thing from a train to a semitruck really should be. It is a very large part of their purpose.

Tracks are a superior design in theory but fail to be flexible enough to work in varying weather conditions and complex dynamic routes. It's better to have invisible guidance rails and let vehicles maneuver easier.

> We can still have electric trucks for the last mile

I think you're grossly underestimating how spread out truck destinations are. You would have to have a very extensive rail network to get cargo anywhere near all the destinations where it's currently trucked. And if the rail network doesn't fall within X average distance of every destination, the value proposition of this idea rapidly becomes negative.

At high velocities (> 40 km/h?) the main drag comes from aerodynamics (turbulence, air viscosity…), not rolling resistance.

perhaps with autonomous cars and rails the cars can follow each other very closely so improves aerodynamics too.

indeed

They already trialed that with trucks where several trucks form a convoy, controlled from the first one. Saves ~30% fuel for the following trucks. That could be used flexibly and probably contain 5-6 trucks minimum without disturbing traffic.

This doesn't make much sense as an urban project, where chargers are close by, lane-switching is frequent, people are likely to be on the road, and which the article invites you to think about by comparing the cost to an urban tram.

but it makes ton of sense for long-distance highway journeys, which is a problem that really needs solving before electric vehicles can be practical.

This is what the article states. They think the 20K km of highways would be more than enough and based on distance from smaller populated areas as little as 5K km.

Although if you had this everywhere, you could probably do away with most of the batteries on electric cars, making them a lot cheaper and lighter.

It would never be everywhere at not in somewhere as vast as Europe or US.

To jump on OPs bandwagon. It would make sense to have this on highways as opposed to surface streets. Distance is one of the limiting factors for a lot of people buying electric.

In the US interstates are at least maintained by the Feds and are pretty standard in look and feel. It would probably be easier to implement nationwide.

>In the US interstates are at least maintained by the Feds and are pretty standard in look and feel.

I don't believe that's true. At least in California, CalTrans does all of the maintenance on state and federal highways alike. AFAIK CalTrans does get paid by the Federal government for interstate maintenance, but that's the extent of the USDOT's involvement in interstate maintenance.

Yes as it turns out they oversee the projects and standards but the actual work is done by state contractors.

> In the US interstates are at least maintained by the Feds

No, they aren't. States are encouraged to focus federal funds given to them for road maintenance on the National Highway System, which includes the Interstates, but the maintenance is done by the states.

EDIT: missed responding to this bit—

> and are pretty standard in look and feel.

The look and feel is due to the AASHTO [0], on which the federal government (via DOT) has only non-voting membership, the same as a number of foreign transportation authorities.

[0] https://en.m.wikipedia.org/wiki/American_Association_of_Stat...

You’re right. What I meant was funded by a federal program.

Not going to work in the snow belt. Maintenance on this will be crazy.

Pretty sure Sweden gets snowy? :)

Pretty sure this tech demo will be shelved after they get tired of it breaking down.

No way this is another thing they can tax.

At close to $1m per km though, it isn't going to be everywhere.

Even on highways, you wouldn't need this to be on 100% of the roads to be useful. You could have, say, a mile of charging rails for every ten miles of road and on lanes that go uphill.

I guess the limit comes down to how much power the rails can produce and how fast the vehicles can charge. If a vehicle can charge at N times the rate they use that energy at highway speeds, then it needs to have at least 1/N of the road populated with charging rails.

If this becomes a widely adopted standard, maybe car manufacturers will look into using a low-capacity battery that can accept high current as a buffer. (Maybe a supercapacitor?)

You can get by with significantly less than 1/N I think. The goal doesn't need to be infinite travel distances, just enough to get to the next destination. Personally, I'm unlikely to drive more than 1000km in a day. Any more than that, and I need to rest for longer than it takes a car to charge.

If electric rails are placed in the road frequently enough to extend the range of an electric car from 400km to 1000km, they've suddenly made electric more practical than gasoline for long distance travel.

That assumes personal cars, which is one of the things that autonomous cars is likely to change; ideally cars will be in use almost all the time, not sitting idle.

Slotcar track that has been scaled up, so: arcing, dangerous, will wear, finicky as hell and impossible to change lanes without losing contact. Probably not the best idea but props for trying.

I'd like to see how it works with a salted wet road too - do they turn it off?

They address that concern in the article. They said the voltage on the surface of the track is only 1 volt when the road is flooded with salty water.

Apparently they tested just that -

Säll said: “There is no electricity on the surface. There are two tracks, just like an outlet in the wall. Five or six centimetres down is where the electricity is. But if you flood the road with salt water then we have found that the electricity level at the surface is just one volt. You could walk on it barefoot.”

They also mentioned they turn off each segment if there is not a car on it. Each segment is 50 meters.

But will slugs be able to safely cross the road?

No. But in a few generations they'll learn not to. In a few more they'll be expert jumpers.

That's actually reassuring, I'm glad they looked into this.

My follow-up concern is, what if, under these salty and wet conditions, something causes a short circuit between the powered rails?

e.g., either a defective vehicle-side contact where the anode and cathode allow for the water and salt to close a much smaller gap, or if someone deliberately sticks a piece of metal on there.

You'll get a small steam explosion but there are lots of ways for the pressure to escape, and if the circuitry protecting the 50 meter stretch is fast enough that might not even happen.

They said nothing about the wear characteristics of the rail when covered in salty road crap.

Stray current wreaks all sorts of havoc on electric light rail systems. I don't see why this would be different.

It is Sweden. If anyone knows salty road crap it is Scandinavians.

It is used for charging batteries, not providing constant power. It disengages on lane change according to the article, but that should not be a problem if there are batteries.

Sure, but you'll be disconnected for that and you're going to have to reconnect on the far side. That's going to cause some arcing and wear. On the plus side, self driving cars will have something to aim for. Provided there isn't any snow or ice to deal with.

Arcing seems trivially prevented by utilizing two-phase connect and disconnect processes. Don't flow current when changing states.

Arcing from a rail that when filled with salt water gives off 1 volts up at road level?

Water under voltage forms a resistor network (effectively). After some distance it's not that deadly if you don't have potential to neutral.

Arcing may also occur under high current situations with low voltage as long as an arc forms early in the disconnect (just test it on your car battery)

Now with Magna-Traction Cars, Headlights for Night Racing!

Why is this considered "the world's first electrified road for charging vehicles"? Compared to https://www.wired.com/2013/08/induction-charged-buses/ for example. Does induction based charging not count as electrified? Is it that the Korean one was for their buses only, not general passenger cars?

"The world’s first electrified road that recharges the batteries of cars and trucks driving on it".

Well, that's a buss.

Jokes aside, the concept is quite old.

https://en.wikipedia.org/wiki/Trolleybus#History

Not easy to disengage though.

The difference is that the one you link has a few induction plates along the route while the other has rails from one end to the other. It's like saying "why do we need electric cars? We already have hybrids!" There are also buses around here that charge at special points along the route. That doesn't make the roads electrified though. Great job from Sweden, no matter if it is world first or not.

That's fair, thanks for the explanation. I legit didn't know the specifics of the Korean technology, just that I had heard the bus can get charge from the road while driving on it.

Wow I always assumed plugin batteries would be the only way to run electric cars, this is great.

Also searching I saw these trucks using overhead electric lines, also in Sweden

https://www.youtube.com/watch?v=27100u7IcII

It seems they're trying a few approaches out to see what works best.

A lot of electric busses in San Francisco also use pantographs, though usually without a substantial battery, meaning they can't disconnect and reconnect like these cars could.

Many of the electric buses in SF do have a backup battery. Not much range, but enough to get it back to the wire if one gets out of position. The older buses needed a tow truck if they became disconnected from power.

When I saw the title I thought it was going to be the first deployment of the Qualcomm system featured on fullycharged[1] back in November. What they've actually done looks... kinda flakey.

[1] https://www.youtube.com/watch?v=2t0E4AcVu6o

Yeah I hoped for something like that too :(

And wet become fantastic skating slopes for motorcycles.

Why cant they just supply kinetic energy? Cars have electric generators themselves. It would be cheaper and safer, just basic cable-car technology. The end-product is kinetic energy, anyway, so basically lossless.

We could have cable-slots at every uphill, and if there is too much traffic, all energy goes just to moving cars. But they have now acquired kinetic energy and can harness it at next downhill section with breaking generators.

I guess this would be very costly and have too many risks of damaged cars and/or injuries by a broken cable.

SanFrancisco-style cable-car has a cable in a slot. It is 200 year old technology, safe to pedestrians and horses.

It could be made even safer with magnetic coupling. The cable has strong permanent magnets and you can attach to these or use alternating magnetic field to generate energy.

Yes but they were all built for that system specifically. And they are significantly slower than cars on a motorway.

I don't think cars going 70mph and frequently linking in & out of the cable would be safe.

This is probably the worst idea I've seen materialize in a long time.

What is the voltage of the track?

If filled with salt water, 1 volt at the surface, but beneath?

Cool, now I can play F-Zero in real life.

I am somehow reminded of when I was a kid playing with my Scalextric and I'd get some no-name brand of car that would be used on a different circuit and voltage, then suddenly having it run 5x as fast as normal on the Sca. track.

Is fast charging and short periods of stopping really that much of an issue?

What happens when the tracks are flooded by rain water. Would it not shortcircuit the tracks? How does one get rid of rain water filled in the tracks to make them operational again?

Sounds like it's a low voltage system with recessed terminals. The article claims that if the road is flooded with saltwater, it's only ~1 volt at the surface.

Next step: wireless induction charging in parking spaces

Unless a revolution comes along in the field, it's too inefficient. Best condition inductive chargers can yield 90% efficiency, and that is not too bad. But that require perfect alignment, and no distance between the coils. Neither is realistic in a "park and charge without doing anything" scenario.

I wonder what is the charging power with this? Can the car sustain its battery infinitely if you drive over electrified highways only?

Yes, but it's still not enough to power your smartphone while it's doing turn-by-turn navigation.

This isn’t all that new - in fact London’s tram system was using it c100 years ago:

http://1.bp.blogspot.com/-UIyXE_Fv3vA/TkLYU8vbHRI/AAAAAAAALb...

Try taking that off the rails and go shopping and see how it works. No comparable at all.

It would be cheaper and more easily scalable to fit more charging points in parking spaces at shopping centres, motorway service stations and so on.

Why do we keep on inventing new complicated ways of doing things instead of standardising and exploiting the things that we already know work?

Electrified rails on trains have been around much longer than parking stations. Plus batteries are the biggest problem (and most expensive) part of ecars, so this is a good idea to try out.

But those rails are on otherwise off-limit tracks and 'third rail' solutions are notoriously dangerous. This system has the two rails closely spaced side-by-side so it may be a bit safer but in the presence of moisture it could be dangerous too.

It's basically a scaled up version of a slot car track.

> This system has the two rails closely spaced side-by-side so it may be a bit safer but in the presence of moisture it could be dangerous too.

Did you read the article? This is addressed.

Yes, I did read the article, otherwise I would not have been able to write what I did, note that the title says nothing about how the electrodes from the car connect to the road. So you could have known that I had read the article. Yes, the article addresses it, no, the article does not address it in a way that gives me a good feeling about the safety of this system in the presence of moisture. It really doesn't take a lot of power to kill a person and even though you can ground-fault-protect the crap out of a setup like this the fact is that such measures can fail and if you start deploying it en-masse in a hostile environment they will fail in large enough numbers that it will not longer be safe.

Note how industrial power is hardly ever ground fault protected because the leakage currents in the standard setup are too high already to reliably detect a ground fault.

In other words: if the system delivers enough power to electrical cars to meaningfully affect their state of charge there is inherent danger.

> the article does not address it in a way that gives me a good feeling about the safety of this system in the presence of moisture

It clearly states that salt water in the rail only gives off 1 volt at road level and that you can walk on it barefoot.

Highways are already off-limit and notoriously dangerous.

Unfortunately, we need to accommodate the future Darwin Award winners. Besides, there's dangerous, and then there's 'the government caused the death of someone who stepped on the highway'. Getting zapped, even mildly, would distract someone and decrease a person's chances of getting out of the way quickly.

Batteries are expensive and heavy. Plus range anxiety.

If this allows for cars to have a 50 mile battery range while still being able to travel unlimited miles on highways, it would be a huge win.

Exactly. The article doesn't expand on this point but this is capable of charging multiple vehicles in motion. More charging points at stations, shopping centers, etc would still require people to stop and wait.

If electric vehicles only had to have a range of a few tens of km (similar to many existing plugin hybrids) they could be built dramatically cheaper. This would also be ideal for buses, lorries and similar.

Something like this? https://www.micro-mobility.com/en/experience-micro/microlino

Good for them for actually trying something.

You actually have to try and make something. Sometimes you get it wrong. That's ok, sometimes you'll get it right. As long as the general trend line is going up, you're doing good.

Because I want to stop for at most 10 minutes every 2 hours. (better yet I want a self driving car where 8 hours latter I wake up where I'm going, and the farther I get in that 8 hours the better) With gas cars we can do this, with batteries that requires a lot of expensive, heavy batteries (the heavy is important because energy is expended just hauling them around).

I don't know if this is a good/useful solution to the problem, but it is an obvious idea to consider.

is this the actual real world implementation of SOLAR FREAKIN ROADWAYS?

I can’t help but be amused at the way people fear cell phone towers but love wireless charging devices

The difference is that the frequencies required for wireless charging are typically much lower if the coupling is magnetic.

The 'wireless' form in the article is more akin to what a trolleybus would use and likely would not survive for long in the presence of either a large amount of traffic (more demand than the rail could handle, imagine a traffic jam) or arcing as well as danger to the public (think subway third rail).

I do not think this concept will survive in the long term.

This one isn't wireless; there's an arm descending from the vehicle.

I'm sure people will fear this too. Driving by the same people who probably will make a ton of money speaking about how bad it is for you. Of course in both cases that science says there is no harm is best shouted down.

I would comment only about the wireless charging case: In medicine there is a wireless device to treat an aggressive form of brain cancer: TTFields. It is approved by the FDA [0]

It works by disrupting microtubules in the cell, a kind of micro-skeleton that gives its shape to the cell.

The TTFields electrical fields have a low frequency, very similar to the Qi wireless charging standard.

[0] https://www.accessdata.fda.gov/cdrh_docs/pdf10/p100034a.pdf

>I can’t help but be amused at the way people fear cell phone towers but love wireless charging devices

how do you know they're not a disjoint set?

Sun can charge battery thru solar panels we all know that. Can Musk use his sattelites network to shoot down a precisely guided laser to charge your Tesla i.e. thru roof/hood made off of solar panels?

"The Deliverator's car has enough potential energy packed into its batteries to fire a pound of bacon into the asteroid Belt. Unlike a bimbo box or a Burb beater, the Deliverator's car unloads that power through gaping, gleaming, polished sphincters. When the Deliverator puts the hammer down, shit happens. You want to talk contact patches? Your car's tires have tiny contact patches, talk to the asphalt in four places the size of your tongue. The Deliverator's car has big sticky tires with contact patches the size of a fat lady's thighs. The Deliverator is in touch with the road, starts like a bad day, stops on a peseta."

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