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Buses can be charged as they drive

The Korea Advanced Institute of Science and Technology has developed a pair of electric buses called Online Electric Vehicles or OLEV. These buses are different from your typical electric vehicles that have to be parked to recharge the batteries. Instead, they can recharge while driving down the road.
Electricity is sent to the bus via cables buried in the road with an 85% maximum power transfer efficiency rate (the wireless charging technology is able to supply 60 kHz and 180 kW of power at a stable and constant rate). There is a gap of just under seven inches between the underbody of the electric bus and the road surface. The charging system uses Shaped Magnetic Field in Resonance [PDF] to transfer power to the bus while it’s in motion.

The underbody of the bus has a receiving device that is able to convert the magnetic fields into electricity. The power strips needed to power the bus only cover 5 to 15 percent of the road surface, so only small sections of road have to be rebuilt to provide service.

Both of the OLEV buses are currently operating in the city of Gumi, South Korea. As of August 6, the buses are running an intercity route between the Gumi Train Station and In-dong district spanning 15 miles round-trip.
The technology used in the OLEV buses is an offshoot of tech used to power trams at an amusement park in South Korea.

Sources:, KAIST

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By Jeffk464 on 8/7/2013 11:05:25 AM , Rating: 4
Interesting if you had coverage all over the city you could get away with a pretty small "buffer" battery.

RE: huh
By Brandon Hill on 8/7/2013 11:07:47 AM , Rating: 3
You are exactly correct. From the PR:

OLEV has a small battery (one-third of the size of the battery equipped with a regular electric car).

RE: huh
By M'n'M on 8/7/2013 12:15:26 PM , Rating: 2
This is how electric cars will become practical. When the major roads are "electrified", battery range becomes a non-concern for all but rural America. The huge expense of a big battery gets mitigated. It's akin to the PRT concept but w/o the rail.

Now we just need to build the nukes to power the system.

RE: huh
By ClownPuncher on 8/7/2013 3:05:41 PM , Rating: 3

RE: huh
By btc909 on 8/7/2013 4:52:24 PM , Rating: 2
Ring, Ring:

Big Oil: Hi this is Big Oil.
Average Joe: Hi, just an average Joe and I had a question.
Big Oil: Sure; what was your question.
Average Joe: Can we build Thorium Reactors.
Big Oil: NO! Click.

RE: huh
By ClownPuncher on 8/7/2013 5:50:30 PM , Rating: 3
If I was Big Oil, I'd be investing in building Thorium reactors.

RE: huh
By Mint on 8/9/2013 2:08:11 PM , Rating: 2
Something like this is actually likely to happen in Canada:

The founder, David LeBlanc, has made a very good case that molten salt is the big advantage of the ORNL experiments, and sticking with a uranium non-breeding design only adds 0.1c/kWh and needs 1/6th the uranium of today's reactors. Thorium and breeding add regulatory hurdles and reprocessing costs all to solve a problem that is insignificant (uranium supply).

His design is the IMSR, and he partnering with oil sands developers to fund it. They need a cheap heat source with high temperature (which current CANDU/LWR designs can't provide) for steam assisted gravity drainage, which allows extraction of bitumen from the ground.

He's trying to simplify it as much as possible: No thorium, no breeding, no reprocessing, and at first, no steam turbine either.

RE: huh
By Breathless on 8/7/2013 4:56:13 PM , Rating: 2
Too bad most of the practicality will be mostly / wholly negated by new taxes.

RE: huh
By Motoman on 8/7/2013 5:12:43 PM , Rating: 2
cables buried in the road with an 85% maximum power transfer efficiency rate

The 85% is what's going to stop that from happening.

They can probably get away with that for the purposes of a relatively small number of city buses in a given metro area.

But it's a non-starter issue for widespread use.

RE: huh
By Jeffk464 on 8/7/2013 5:46:52 PM , Rating: 2
Electric motors have a much higher efficiency rating than gasoline engines. So I'm thinking a loss of 15% is probably really do-able.

RE: huh
By Hoser McMoose on 8/7/2013 6:36:45 PM , Rating: 2
Electric motors do have higher efficiency, but this 15% loss is only one of many places where energy is lost in the whole chain of things, the biggest of which is simply in generating the electricity in the first place.

Probably not a fatal flaw overall, and even with a wired connection there is going to be some loss in transfer power from the wall to the car (a lot less than 15%, but greater than zero), but it is just one more area of efficiency loss that makes the solution less attractive.

RE: huh
By Paj on 8/8/2013 7:29:47 AM , Rating: 2
I;d say that pretty good, when you consider that conventional ICEs lose up to 75% of the energy generated as waste heat.

RE: huh
By Hoser McMoose on 8/7/2013 6:43:51 PM , Rating: 2
There are two really big problems I can see with this setup for widespread use of such a technology:

1. *HUGE* infrastructure cost to dig up the roads and put in the electric grid. Sure you can wait until you need to dig up the roads and repave them anyway, but that means that it will take a VERY long time before you have decent enough coverage to make it practical.

2. Along with the issue of generating and transmitting the electricity, this would tend to make things much worse than batteries that are charged after a trip is ended. Since these cars would need to be getting charged while they are driving you need to generate the electricity when people are driving most, and that means a lot of extra generating capacity required at rush hour times. Unfortunately the afternoon/evening rush hour already closely corresponds to peak electricity demand. Where the 'charge after the trip' batteries could mostly be scheduled to charge overnight (low demand), these 'charge on the fly' cars will add a lot of demand at near peak times.

The result is a lot more generating capacity required, more upgrades to transmission facilities and less efficient spread of when electricity is generated. The latter is particularly bad for nukes which really work best when they can generate full power 24/7 rather than having to ramp up for a few 'peak' hours in the late afternoon then scale back down to almost nothing overnight.

RE: huh
By Jeffk464 on 8/7/2013 8:07:17 PM , Rating: 2
2 is a really good point

RE: huh
By ShieTar on 8/27/2013 9:09:43 AM , Rating: 2
I'm going to say it is a semi-good point. As long as batteries remain rather heavy, there might still be a point in storing electricity in static batteries and supplying the energy to the lighter cars with the smaller batteries. This also has the benefit that all the battery-capacity is always connected. When the batteries remain in the cars, they will still often be parked without a connection to the power network.

Setting up a nation-wide system seems unlikely for now, but it might by an interesting perspective for a single big city. Once you installed it on all streets for your public transport, at least cabs and local delivery services could adopt their cars to also use it. Your trash trucks and maybe firetrucks, police cars can be equiped with it. And possibly a good number of people will buy themselves city-cars for the daily trips, and keep a second long-distance car. Or you just set up an effective Car-Sharing service for such city-cars.

RE: huh
By DT_Reader on 8/7/2013 8:18:16 PM , Rating: 2
If they had coverage all over the city, you could run your personal car free by leeching off the bus system! I can see quite the black market in Prius retro-fits :-)

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