Wirelessly charging electric cars as they drive
news.stanford.edu
news.stanford.edu
It’s a good point, though outside the US there are also entrepreneurs. Politics/regulations might work differently. There could also be incentives to do things like this.
EVs already provide enough range for commuting. The vast majority of the population commutes tens of miles, and EVs can regularly do hundreds of miles. So there’s really no need to modify roads for the sake of commuters.
For longer distance travel we really should be talking less roads and more high speed rail. They’re faster, safer, and more efficient than cars. It’s also a less uncertain technology; there are several countries with highly successful high speed rail systems that we could copy.
For freight we should use regular rail for similar reasons, plus the fact that using semi trucks, diesel or EV, creates a large financial burden on the public to undo the damage that heavy trucks do to our roads.
Even if real-world use was a tiny fraction of miles traveled, I think people would be much more apt to buy electric if they knew that the cars could charge as they drive. You could implement it such that the car communicated with the road and was delivered a charge only if it was beyond a certain number of miles that day to reduce load on the network and incentivize overnight charging.
Regarding high-speed rail, the whole point of driving your car to the destination is to have a car at the destination; high-speed rail where you arrive and have to walk is a non-starter for a lot of destinations right now. I agree that we should reduce the effective subsidy that heavy freight trucking currently benefits from so businesses are economically motivated to switch to more rail freight.
Besides, any solution to range anxiety has to be tuned to the social benefit it would generate. I’d be more a fan of simply making gasoline more expensive, since what we really need is not people using EVs, but people not using fossil fuels.
- L1 charging is 3-4 miles / hour. - Charging infrastructure is horrendously unreliable. (non-Tesla). I don't do much outside charging, but in 40% of my experiences, chargers are often out of service, throw errors, or not maintained well. (I was at an popular Electrify america spot and 3 of 6 chargers were out of commission, 2 of them were like that for weeks)). - Charging is expensive. More expensive than gas, sometimes ripping you off. Session fees of $3 just for plugging in, plus 4x residential kwh rates.
In cities, in where lots of people don't have a personal parking space, there's the charging problem, just like now there's the parking problem.
Some days I had to search for more than 30 minutes for a spot to park in. Add the charging requirement and I would feel anxious in less than a week.
Yes, and EV drivers are used to charging up their cars at charging stations.
Wireless on-route charging is not needed for the same reasons that we don’t need to refuel our cars while driving down the highway.
The real cause of range anxiety in modern EVs is that in many parts of the world there aren’t enough charging stations. But it’s much cheaper to build more charging stations than to dig up roads and retrofit them with wireless charging infrastructure!
(As another data point, I see Teslas regularly parked in my London neighbourhood outside homes that do not have any off-street parking/charging. So at least some EV owners get by without any home charging at all)
[1] https://www.thisismoney.co.uk/money/cars/article-8263039/UK-...
Again, it seems like selection bias, in that those high-mileage drivers who can use electric do, and those that can't buy diesel. Presumably there is a cohort of diesel drivers who would switch to electric if they offered sufficient range or faster charging, especially as diesels outnumber electrics ~2.5:1 in the UK [2].
[1] https://www.autoexpress.co.uk/tesla/352144/tesla-drivers-cov... [2] https://www.statista.com/statistics/299031/fuel-types-of-new...
There's still a significant price gap between comparable diesels and electrics.
Norway's experience (60%+ market share for electric vehicles) suggests that if the price is comparable, and charging is convenient enough, the majority of buyers will choose electric.
No, in the Bay Area, people buy SUVs to "feel taller" when driving in traffic.
The 50mins I takes me to charge my Kona every ~210 miles is roughly when I should be taking a break of roughly an hour anyway. "Technology Connections" on YouTube has a really fantastic (and old) video on this subject: assuming level 1 (110V) at home and at work, you'd basically never need anything more than level 1 charging for commuting. EVs require a surprisingly small amount of energy.
> high speed rail
I have understood the efficiencies in rail since I was maybe 12. It blows my mind that it is such a niche mode of transport (especially for goods, transporting humans isn't where the real savings are) in so many places around the world. From a purely economic standpoint (forgetting environmental issues entirely), it makes complete sense to aim to have zero semis on roads between cities. Trains should be long-haul, semis should be last-mile.
There is a reason semi's are long-haul. A fleet of semi's is tremendously flexible, with single loading and single unloading.
The fleet can be driven in a myriad of ways and constantly re-routed for suit the present requirement.
Trains are good for a specific types of cargo, ex. to and from ports.
And if I'm shipping something in the form-factor of a parade float, I'd want to load it once on a truck, not on a truck and then a train.
Interestingly, the US is actually pretty good at rail freight. They de-regulate most rail freight a few decades ago and are doing fine. The Economist had a special report about it a few years ago (https://www.economist.com/briefing/2010/07/22/high-speed-rai...) proudly proclaiming: "America’s system of rail freight is the world’s best."
> Amtrak's passenger services are sparse compared with Europe's. But America's freight railways are one of the unsung transport successes of the past 30 years. They are universally recognised in the industry as the best in the world.
> Their good run started with deregulation at the end of Jimmy Carter's administration. Two years after the liberalisation of aviation gave rise to budget carriers and cheap fares, the freeing of rail freight, under the Staggers Rail Act of 1980, started a wave of consolidation and improvement. Staggers gave railways freedom to charge market rates, enter confidential contracts with shippers and run trains as they liked. They could close passenger and branch lines, as long as they preserved access for Amtrak services. They were allowed to sell lossmaking lines to new short-haul railroads. Regulation of freight rates by the Interstate Commerce Commission was removed for most cargoes, provided they could go by road.
> Before deregulation America's railways were going bust. The return on capital fell from a meagre 4.1% in the 1940s to less than 3% in the 1960s. In 1970 the collapse of the giant Penn Central caused a huge shock, including a financial crisis. By 1980 a fifth of rail mileage was owned by bankrupt firms. Rail's share of intercity freight had slumped to 35% from 75% in the 1920s. Tracks were neglected and fell into disrepair, leading to a downward spiral of speed restrictions and deteriorating service. The term “standing derailment” was coined to describe the toppling-over of stationary freight wagons when the track gave way beneath their wheels.
(You can use outline.com to get past the Economist's paywall.)
Being able to directly store energy into their batteries (or maybe even have the vehicle directly use it, without having to store it in its battery, just as many portable PC can do) as it is produced and without any intermediate storage (maybe even without the usual AC<->DC transformation(?)) may justify such a system.
Consider how much more virulent the 5G panic would be if 5G involved these kinds of power levels. I feel like politically this is at least 50 years from being viable even if the technology were perfect today.
https://www.latimes.com/archives/la-xpm-1996-06-28-mn-19436-...
Maybe, the whole idea is just a marketing stunt to catch the eye and interest of the average person to prop the technology in the media. Because wireless charging definitely has many applications.
More specifically, this specific results builds on an insight from the same research group which led to a Nature paper in 2017: https://www.nature.com/articles/nature22404/ - that using an non-linear saturable gain element in a parity-time symmetric configuration enables robust power transfer in a range of conditions such as moving and the presences of obstacles. There's interesting underlying science here that shouldn't be missed for the focus on the application.
https://www.greencarcongress.com/2020/05/20200508-witricity....
There are academic connections between the group at Stanford publishing this work and the group at MIT that founded WiTricity.
I'd look for applications where a system cannot stop moving, otherwise isn't in physical contact with infrastructure / cannot be accessed, or absolutely can't tolerate additional weight.
This is a good idea, which hasn't even been demonstrated to work with electric cars and roads.
What it has been demonstrated to work for, is robots in warehouses, and in that context it's great: this would allow ~99% utilization and obviate laying out warehouse space for charging docks.
Well, yes, moving tens of kilowatt-hours of energy in milliseconds wirelessly to a moving target with a lithium based rechargeable battery is an unsolved problem.
Who woulda thunk.
This has a much better application for parking lots. Dedicate some percentage of spaces as charging spaces and power vehicles at rest. It doesn't need to deliver a high power charge to be useful.
Heck, this even makes sense for loading docks/semi. Put these induction chargers at every loading bay and let the electric semis charge while they load and unload.
As mentioned elsewhere in the thread, charging forklifts or something in a warehouse in motion, or while briefly stopped drives up how long you can use an electric powered device, and the added utility pays for efficency loss.
Of course, it's easier to add this to cover enough of a warehouse than to cover enough of a highway system.
I love the idea of using magnetic inductance to charge at a distance but with all that flux even small loops of conductors might be in danger of generating a serious voltage potential across them.
Or smaller yet - slot cars.
(Not technically wireless or battery powered, but still)
So adding a road tax for EVs eventually would have to happen to offset the loss of revenue.
In their first breakthrough three years ago, the researchers developed a wireless charger that could transmit electricity even as the distance to the receiver changes. They did this by incorporating an amplifier and feedback resistor that allowed the system to automatically adjusts its operating frequency as the distance between the charger and the moving object changed. But that initial system wasn’t efficient enough to be practical. The amplifier uses so much electricity internally to produce the required amplification effect that the system only transmitted 10% of the power flowing through the system.
In their new paper, the researchers show how to boosts the system’s wireless-transmission efficiency to 92%. The key, Assawaworrarit explained, was to replace the original amplifier with a far more efficient “switch mode” amplifier. Such amplifiers aren’t new but they are finicky and will only produce high-efficiency amplification under very precise conditions. It took years of tinkering, and additional theoretical work, to design a circuit configuration that worked."
A resonant structure (AKA "antenna") can be thought of as Star Trek's Transporter, version 0.0000001...
A resonant coil, 0.0000002...
A resonant coil to transport electricity, 0.0000003...
Then of course there's this:
https://www.youtube.com/watch?v=NB_hF_K_7cc
2:28:
Montgomery Scott: "What's that?"
Alternate Universe Mr. Spock: "Your equation for achieving transwarp beaming..."
[He shows Mr. Scott the equation on screen...]
Montgomery Scott: "Imagine that! It never occurred to me to think of space as the thing that was moving!"
It's straightforward to do that with a split transformer. Berkeley used to have an electric bus which recharged at bus stops that way. More trouble that it was worth, but it worked. There's an old patent from, I think, GE, for a scheme for long transformers below highway lanes to do the same thing. The practical question is whether this new thing is substantially better.
Parity–time symmetry is a concept from quantum optics. The author, from his papers, used to do optical work. There's been work on this in the magnetic domain, but at very small scales, like nanometers.[3] Doing this on a scale of meters is new.
No idea whether this makes any sense. None of the non-paywalled papers have anything useful to read. Anybody enough into quantum magnetics to make sense of this?
[1] https://web.stanford.edu/~sca/
[2] https://www.livescience.com/59487-wireless-power-systems-cha...
Either way, it's an interesting application. I'm not sure how wild you could go with this right now, given all the roads that exist already, and the cost that would come along with it. Or maybe the traffic implications of people climbing to get on those free charging roads?
But public transit seems like a smart use for this kind of thing. Takes a predictable path, for a (somewhat) predictable about of time, on a loop all day. If you designed it right, perhaps you could drive that bus along that route until it breaks down?
https://mst.org/news_items/media-invitation-cord-cutting-for...
There is aleady a decades-old system in widespread use for delivering electrical energy to moving vehicles. It isn't rocket science. It's called a "wire".
"In their new paper, the researchers show how to boosts the system’s wireless-transmission efficiency to 92%. The key, Assawaworrarit explained, was to replace the original amplifier with a far more efficient “switch mode” amplifier."
There are other comments about political feasibility, but what if the same system became a way to re-produce the tax for use we originally built into gasoline.
Obviously theres a bunch of tax evasion / self charge cases that would need to be considered.
That way if you're taking a long trip (when you usually need extra luggage) you can also bring all the other stuff. Skis, food, clothes, bikes, kayaks, whatever it is you're doing. It all goes on the trailer.
Yeah it's not all that great that it's burning diesel (or biodiesel or whatever) but if you could convince people to drive strictly electric cars the other 355 days a year I think you'd see big improvements in nearly all metrics people care about nonetheless.
...and you have a Chevrolet Volt, BMW i3, or Fisker Karma.
How about truck by-lanes across the country are equipped with electric cables on poles, and trucks have those train type extenders to get charged. Or even charging stations in truck stops.
And wireless charging is in-efficient.
Solar voltaic has its own weird reliability issues but the panel does produce unusable amounts of power most of the day. (if your plan is to transport it)
Good weight/kwh ratio batteries are expensive.
If you can have the batteries roll along the power source for free the wind and sun could be offered very cheaply.
Wireless I dunno, overhead cables or contact rails in the road seem fine. Still costly but reasonable.
Pondering this it struck me how wonderful this ancient tech is.
https://www.rac-info.nl/lv/images/lvtrekschuitenpaard.jpg
Its A horse pulling a boat!
We could put rails by the side of the road with drones on them (mechanical horses) hook up any old clunker by its towing ring, cut dramatically into fuel consumption, reduce tire wear and get rid of much of the driving idiocy.
It gets more spectacular where you can dump mechanical energy into vehicles while it is available.
I have no idea at what speed conventional cars are still usable but I see far less need for a speed limit if everyone drives in formation. If someone hits the breaks the drone can detect it and slow down the car behind it. Perhaps 2 cables, one at the front and one at the back.
Charging the battery over cables gets pretty obvious at this point. (there is regenerative breaking too!)
To add a final bit of hilarity: If we stop gluing batteries into appliances (ffs?) fit them to the bottom and make them easy to swap by driving over a swapping station... then the fully charged battery is more valuable than the empty one.
This can drive the cost per km down below zero.
Pretty glib considering the current 5g controversy
I wonder if putting the system before lights at intersections would help to buy, so to say, people. If it would be cheaper and more convenient for them directly. I think the problem with 5g is that it is not entirely clear how better is it. Also there are probably more people driving, then using mobile Internet. Or at least more people that would protest such undertaking.
Did science ever carry any authority on it's own? In the last few decades I've been living in the United States, I honestly don't think it has.
> I'm not sure what to do about it though.
I think what we're seeing now is really organized emotional manipulation on a massive scale. I seriously doubt that any of these conspiracies are truly organic, or if they are, that their current scale is organic.
Worse still is it's impossible to determine who is doing the pumping. Is it "activist" groups looking for funding? Is it "corporate" groups looking for legal leeway? Is it bored kids on the internet looking for entertainment?
As to what to do about it, I think the answer basically starts with a lot more investigative journalism. We don't do that anymore. It creates a vacuum that allows these groups to thrive.