A city in South Korea just turned on its first network of roads that power electric vehicles as they drive. 
 
 It sounds like science fiction, but it could be a look at the future of transportation. 
 
 As ExtremeTech's Sebastian Anthony reports, the city of Gumi, South Korea has "electrified" 15 miles of road. 
 
 It works by transmitting electricity through cables about a foot below the road. By running power through the cables at a specific frequency, an electromagnetic field is generated. 
 
 A coil located underneath vehicles interacts with this field and generates a current, charging the vehicle's batteries. 
 
 While the city is currently only using the technology with a few electric buses, it's easy to see how the technology would completely change the logistics and cost of owning an electric vehicle. 
 
 It would ameliorate the range problems people have with electric cars. Currently, most electric cars that don't also have a gasoline engine (like the Chevy Volt does) can only travel about 100 miles or less before they need to recharge. Many Americans don't like the idea of having to make frequent stops to recharge on road trips, making range a dealbreaker. 
 
 With roads that charge your car as you drive, range is less of a factor. And if that's the case, then batteries can become smaller and cheaper. 
 
 Forbes' Bob Lutz estimates that the Chevy Volt's battery costs about $6,000. If Chevy could assume that drivers don't need to worry about range, they could move to a cheaper battery with less capacity, like Toyota's Prius Plug-In. That would shave several thousands of dollars off the price of the battery and make the car more profitable to produce. 
 
 An obvious point to bring up is the cost of rolling out electrified roads. The research study behind Gumi's network concluded that only 5-15% of roads need to be electrified for the concept to be viable. 
 
 Basically, local and state governments would need to bury the necessary cables as they repave roads. While that's easier said than done, it seems like an easier step than asking Americans to change their driving habits. ||||| South Korea has rolled out the world’s first road-powered electric vehicle network. The network consists of special roads that have electrical cables buried just below the surface, which wirelessly transfer energy to electric vehicles via magnetic resonance. Road-powered electric vehicles are exciting because they only require small batteries, significantly reducing their overall weight and thus their energy consumption. There’s also the small fact that, with an electrified roadway, you never have to plug your vehicle in to recharge it, removing most of the risk and range anxiety associated with electric vehicles (EVs). 
 
 The network consists of 24 kilometers (15 miles) of road in the city of Gumi, South Korea. For now, the only vehicles that can use the network are two Online Electric Vehicles (OLEV) — public transport buses that run between the train station and In-dong. 
 
 Exact details of the system are hard to come by, but we believe that the power is delivered by cables that are around 12 inches (30cm) below the road surface. The power is transmitted wirelessly via Shaped Magnetic Field in Resonance (SMFIR), a technology developed by the Korea Advanced Institute of Science and Technology (KAIST) that essentially runs 100 kilowatts of power through some cables at a very specific frequency (20 kHz in this case), creating a 20 kHz electromagnetic field. The underside of the bus is equipped with a pick-up coil that’s tuned to pick up that frequency, and thus AC electricity is produced via magnetic resonance. (Read: How wireless charging works.) Transmission efficiency is an impressive 85% thanks to the “shaped” part of the technology, which targets the electromagnetic field at the vehicle, so that less energy is lost to the environment. 
 
 The OLEV receives 100 kilowatts of power via SMFIR, while maintaining a 17cm gap between the underside of the bus and the road surface. Because each OLEV has a small battery (about one-third the size of the battery in a conventional EV), only small portions of the road (5-15%) need to be electrified. Further increasing efficiency and reducing the radiation received by other road users and pedestrians, the electrified sections only turn on when an OLEV approaches. (In case you do get caught near a strip of electrified road as an OLEV passes by, the level of radiation produced by SMFIR is well within the limits imposed by international EMF standards.) 
 
 Moving forward, 10 more buses will be added to the network by 2015 — and presumably there are also plans to add more stretches of electrified roads. The fact that only 5-15% of the road needs to be dug up and replaced might sound positive at first blush, but it’s still a massive undertaking in any kind of built-up area. Trains and trams might require electricity for their entire runs, but it’s much easier to install overhead power lines than to dig up a road. 
 
 Still, if we push the logistical issues aside for a moment, it’s hard to overstate the advantages of a nationwide electrified road network. You would never need to stop at a filling/charging station ever again. The design and engineering of cars would change dramatically, as large engines, fuel tanks, and batteries would no longer be required. Reducing our reliance on fossil fuels would of course be a boon to the environment, too. The electric road would be a network in the computer sense of the word, too, potentially allowing for all sorts of vehicle tracking, autonomous driving, vehicle-to-vehicle networks, smart braking, and more. 
 
 It’s just a shame that we’re probably decades away from a nationwide electrified road; the installation costs, in terms of construction work and lost productivity due to traffic delays, would really be quite phenomenal. 
 
 Now read: German student creates electromagnetic harvester that gathers free electricity from thin air 
 
 Research paper: Application of Shaped Magnetic Field in Resonance (SMFIR) Technology to Future Urban Transportation [PDF]
– The future is now—in the South Korean city of Gumi, anyway, which just enabled 15 miles of road to recharge electric cars as they drive along, Business Insider reports. Cables about a foot underground generate a 20-kHz electromagnetic field, which is absorbed by a coil in the bottom of the vehicle, ExtremeTech explains. The system now works with two public buses, but 10 more are planned by 2015. Each has a battery one-third the size of a standard electric vehicle's, which makes the system even more efficient, as the buses weigh less and consume less energy.