Abstract
This chapter provides a basic description of OLEV and its enabling technology of SMFIR (Shaped Magnetic Field In Resonance). It then briefly compares OLEV/SMFIR with other vehicles that use IC engines and other electric vehicles in terms of environmental impact, performance, and cost, which are explored further in Part IV of the book. It also explains the potential benefits of electrifying ground transportation systems (EGTS) with a technology like OLEV and connecting these systems to smart electric grids. Finally, it describes efforts made to commercialize OLEV and lessons from these efforts.
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Notes
- 1.
Attempts to use wireless technology to charge electric vehicles have a long history. In 1894, Nikola Tesla, who spent many years experimenting with the wireless transmission of electricity, received a U.S. patent for his invention of an electric railway system using inductive coupling, although his idea was never put to use. In the 1990 s, General Motors and Toyota experimented with inductive charging in their first electric vehicles, and in 2002 a system of inductive charging (manufactured by the German firm Conductix-Wampfler) was implemented on city buses in Turin and Genoa, Italy. The Italian buses, however, use stationary charging, meaning that the vehicles can be charged only when stopped over induction coils installed in the road. See Markkus Rovito, “OLEV Technologies’ dynamic wireless inductive system charges vehicles while in motion,” Charged, 5/1/14, https://chargedevs.com/features/olev-technologies-dynamic-wireless-inductive-system-charges-vehicles-while-in-motion/ (originally in Charged Issue 12–FEB 2014).
There are many ways of sending electric power over a large distance. One of oldest technologies for this is the electromagnetic radio signal transmitted by TV or radio antennas. The signal is propagated over a long distance, but because it is weak it must be picked up and amplified by supplying external electric power to the TV or radio. The technologies for wireless power transfer to EVs that have been tried may be classified into the following three types:
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1.
Magnetic induction
AC current flowing through a circular ring will generate three-dimensional magnetic waves. This field is picked up by a pickup unit mounted on a vehicle. This inductive technology has a basic limitation for EVs: the three-dimensional shaped magnetic field it generates cannot be picked up by another coil (on top of it) unless the two coils are in close proximity. Therefore, in some wireless power transfer technologies that use this technology, the top pickup unit is lowered to bring it into the requisite proximity to the bottom coil align precisely to obtain acceptable efficiency. This technology cannot be applied to moving vehicles.
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2.
Magnetic resonance
WiTricity Corp. has developed a technology based on an invention by Professor Marin Soljačić of MIT. In this technology, the coils generate electromagnetic waves that are picked up by a resonator at a large distance. This technology cannot be used to transmit the high power needed for transportation, however.
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3.
Shaped Magnetic Field in Resonance (SMFIR)
This technology, pioneered by OLEV, is different from the above technologies in several important ways:
-
(a)
It uses ferrite cores to shape the two-dimensional magnetic field in order to create a “magnetic field path” from the bottom ferrite core to the core attached to a moving vehicle. The high-intensity field is confined in a relatively well-defined space between the ground and the vehicle. This is equivalent to creating a loop from the poles of the underground ferrite core (think of the top two ends of the letter U as the two poles) through the poles of the top ferrite core (an inverse-shaped U) of the pickup unit attached to the vehicle. As the magnetic field oscillates through these ferrite “loops,” we pick up the energy associated with the magnetic field using the resonance effect. In order to pick up the magnetic field, the top pickup unit must be in resonance with the field frequency of the lower unit imbedded in the ground, which creates a “continuous loop” of magnetic field. This is why we call our technology “Shaped Magnetic Field in Resonance” (SMFIR), which is a patented technology.
-
(b)
We control the height of the heavy magnetic power transfer by changing the width of the two ends of U-shaped ferrite cores; the farther apart they are, the greater is the height the field can reach.
-
(c)
Unlike magnetic induction, which generates a three-dimensional magnetic field, OLEV generates a two-dimensional magnetic field along the direction of the vehicle motion by having a series of U-shaped ferrite structure of the lower unit imbedded in the ground, which creates a “continuous loop” of magnetic field. This is why we call our technology “Shaped Magnetic Field in Resonance” (SMFIR), which is a patented technology.
Additional technical detail about SMFIR is provided in later chapters of this book. The technology for shaped magnetic field in resonance (SMFIR) system, a critical part of the development of OLEV, was designed and implemented by researchers at KAIST under the leadership of Professor D.H. Cho, using the theoretical design framework of axiomatic design. There are a large number of patents covering these technologies. For further discussion of wireless technology and its various uses, and of future applications for SMFIR, see Chap. 19.
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1.
- 2.
Typical high-speed trains in Korea run at about 300 km/h. What limits their speed is the mechanical sliding contact between catenary electric wires and the pantograph on top of the train for transmission of electricity. Since the OLEV train runs on rails, its efficiency is expected to be up to 90% higher than that of the OLEV bus, because the pickup unit can be closer to the emitting unit. For additional discussion of wireless power transfer technology for trains, see Chap. 17.
- 3.
One interesting application area is the use of SMFIR to transmit electric power wirelessly to ships. Since the magnetic field is not affected by water, the SMFIR system can be deployed in water. A ship can charge its battery while in dock or while in motion in shallow waters.
- 4.
Implementing such a system, this study found, would cost approximately $900,000 per bus for purchase of the vehicles plus installation of the OLEV infrastructure. This compares with a cost of approximately $600,000 per bus for the purchase of six CNG buses (factoring in the government subsidy of $300,000 for each OLEV bus and $100,000 for each CNG bus; typical heavy-duty diesel buses cost from $200,000 to $600,000 [3]). However, the initial cost for the OLEV system would be offset by fuel savings over a ten-year period (during which the fuel costs for CNG buses would significantly surpass the fuel costs for OLEV buses). To make one round trip, a CNG bus uses $20.58 worth of fuel, but the OLEV bus uses just $3.92 worth of electricity. Over ten years, this adds up to $4,500,000 of fuel for the six CNG buses, and just $860,000 of electricity for the six OLEV buses. Adding in the carbon tax of $401,000 for the use of natural gas, the total operating and capital cost of the CNG buses is about $5,510,000 over ten years, while the OLEV buses cost $2,659,000—about 50% less than the CNG bus system. Even without the government subsidy for the buses, the OLEV bus system still costs about $1.5 million less. This study also estimates that over a ten-year period, the overall cost of an OLEV system is 40–60% that of an equivalent diesel bus system, because of fuel savings.
- 5.
This analysis was based on a proposal submitted to the government by a city in Korea for a bus rapid transit (BRT) system. It assumed a 20 km bus line traveled by fifteen buses running at four-minute or ten-minute intervals (except for the PEV system, which would require an additional seven buses due to the thirty-minute battery charging time). The analysis also assumed an amortization period of nine years. The total operating cost was calculated based on the costs of the buses, the infrastructure, the fuel, and the CO2. The CO2 cost was calculated under the assumption that 50% of the electricity was generated by nuclear power plants, via a formula advanced by a national environmental research institute in Korea.
- 6.
Regardless of the speed of the OLEV vehicle, the time required to recharge the battery for use on roads without the underground power supply system remains the same. Therefore, as the average speed of OLEV increases, the length of the underground power supply system must be longer to maintain the same charging time.
- 7.
Energy Data Handbook 2013.
- 8.
The cost of petroleum fluctuates. In 2015, it came down to about $50 a barrel.
- 9.
This is lower than Rao’s estimate of 60%.
- 10.
The system installed in Gumi City cost $1.4 million for 35 km (~22 miles), or $64,000 per mile. It incorporated six charging stations, each costing about $230,000. A new installation in the same city is budgeted to cost $150,000 per charging section. The number of charging stations required increases with average vehicle speed, so highways require more of them than city streets. Two million dollars per mile is a generous allowance to cover costs such as installing electric power supply lines in Korea. In America the cost of the power supply infrastructure will be higher than $2 million per mile, and in China it will be lower, due to differences in the cost of power components and equipment in the two countries.
- 11.
Per Liljas, “America’s Safest Car Ablaze After Fire Starts in Battery Pack,” Time, October 3, 2013 (http://business.time.com/2013/10/03/americas-safest-car-ablaze-after-fire-starts-in-battery-pack/, accessed December 5, 2015.) In January 2016, a 2014 T Model S was destroyed after bursting into flames while charging at one of Tesla’s “Supercharger” stations in Norway; see Clifford Atiyeh, “Tesla Model S Catches Fire at Supercharger Station in Norway,” Car and Driver, January 4, 2016 (http://blog.caranddriver.com/tesla-model-s-catches-fire-at-supercharger-station-in-norway/, accessed January 5, 2016).
- 12.
Joshua Parlow and Joby Warrick, “A Dangerous Export—America’s car-battery wastge is making Mexican communities sick”, Washington Post, February 26, 2016 (http://www.washingtonpost.com/sf/national/2016/02/26/a-dangerous-export-americas-car-battery-waste-is-making-mexican-communities-sick/).
- 13.
As battery technology continues to evolve in the direction of greater efficiency and safety, OLEV will benefit, as it uses small batteries for free autonomous mobility on roads without the underground power supply system.
- 14.
U.S. Energy Information Administration. http://www.eia.gov/tools/faqs/faq.cfm?id=77&t=11.
- 15.
U.S. Energy Information Administration. http://www.eia.gov/tools/faqs/faq.cfm?id=307&t=10.
- 16.
To manage the dynamic nature of an electric grid with many diverse energy sources, sinks, and storage sites (and where some individual nodes can act as either a source, sink, or storage unit at various times), information must be measured and transmitted among all the elements on the grid including central power generation plants, distributed generation and storage systems, transmission nodes and plants, and consumers (stationary or mobile). This is the reason for making the electricity grid “smart.”.
- 17.
As this report notes in another place, “In high renewable penetration scenarios, curtailment of renewable generation occurs seasonally when load is low and renewable generation is high. Electrified roadway scenarios move some of the load that would have occurred in the evening to the daytime periods and thus offers new load that can utilize the excess renewable generation.” Laura Vimmerstedt et al., Transformative Reduction of Transportation Greenhouse Gas Emissions: Opportunities for Change in Technologies and Systems (Golden, CO: National Renewable Energy Laboratory, April 2015), pp. 45, 47. The author is grateful to one of the report’s co-authors, Tony Markel of NREL , for answering questions about its findings.
- 18.
These two angel investors were Dr. A. Neil Pappalardo, the founder and CEO of MEDITECH, Inc., and Dr. “BJ” Park, the founder and former CEO of MTL, Inc.
- 19.
The first president of OLEV Technologies, Dr. Hikyu Lee, attempted to sell the patented and proprietary OLEV system for use with buses in the United States. As each OLEV 20 kW power unit weighs 400 lbs., the technology is currently too heavy for smaller vehicles but still lighter than the battery packs carried on battery-powered electric buses. A regional port authority showed interest in purchasing the system for airport buses but balked at the idea of OLEV Technologies, a for-profit company, making a profit from the sale.
In 2013, with OLEV Technologies having gone through its first round of funding, the board wanted new leadership to pursue opportunities for sales to the private sector. We brought in Bryan S. Wilson, who had spent the previous twelve years developing infrastructure for the wireless communications industry. The company’s two angel investors put in a second round of funding and Wilson began to looking to sell the OLEV technology to concerns including shuttle operators, ports (where electric vehicles are an attractive option for transferring cargo from ships to trucks and trains and vice versa), and mining companies. A major multinational corporation with mining interests showed interest in OLEV for electric mining vehicles that operate underground (making battery charging and swapping challenging), but wanted to have a product to try out; not being in the business of producing vehicles, or having relationships with OEMs that could produce vehicles equipped with OLEV pickup units, OLEV Technologies was unable to supply a product. A company that makes vehicles for airport baggage transfer expressed interest in having its vehicles equipped with OLEV technology, but the technology costs more, at present, than the vehicles it would have been installed for. A heavy equipment manufacturer making electric vehicles for which OLEV would be a good fit appeared to be another prospect, but was still trying to develop its own customer base for its products. As these sales efforts came up short, OLEV Technologies began seeking grant money from government agencies interested in trying out its system, only to have these initiatives founder on the complexities of doing business with government.
- 20.
For a description of Bombardier’s PRIMOVE wireless power transfer system for trams, see Chap. 17.
- 21.
Sweden and the U.K. are two countries where the government has been funding, or has pledged to fund, research on the feasibility of electrified roads for vehicles using wireless dynamic power transfer. In Sweden, a project launched in 2010, managed by Volvo Group Trucks Technology, and partly financed by the Swedish Energy Agency studied and proposed means of transmitting electrical energy from highways to vehicles via both conductive and inductive (i.e., wireless) technology. Scania AB, the Swedish commercial vehicle manufacturer, and Bombardier developed the project’s “inductive energy transfer solution” based on Bombardier’s PRIMOVE. In 2014, two organizations involved in this study, the Swedish Transport Administration and the research institute Viktoria Swedish ICT, partnered with the independent Swedish National Road and Transport Research Institute to test electrified roads employing both conductive and inductive technology in a “driving simulator.” In 2015, the U.K.’s Transport Minister, Andrew Jones MP, announced that the government was allocating £500 million ($781 million) over five years to finance off-road trials for road electrification using dynamic wireless power transfer technology. Both countries have also begun implementing wirelessly charged city buses. See Viktoria Swedish ICT on behalf of Volvo GTT and Scania CV, “Slide-in Electric Road System, Inductive project report” (Scania CV, October 18, 2013), pdf available at https://www.viktoria.se/sites/default/files/pub/www.viktoria.se/upload/publications/slide-in_inductive_project_report_draft_phase_1_2013-10-18.pdf (accessed January 6, 2016); VTI (Swedish National Road and Transport Research Institute), “Electric roads: a solution for the future,” press release January 16, 2015 (http://www.vti.se/en/news/electric-roads-a-solution-for-the-future/, accessed January 6, 2016); Highways England and Andrew Jones MP, “Off road trials for ‘electric highways technology,” press release August 11, 2015 (https://www.gov.uk/government/news/off-road-trials-for-electric-highways-technology, accessed January 6, 2016); Federico Guerrini, “The UK Will Be Trialling Roads That Wirelessly Recharge Your Electric Vehicle While You Drive,” Forbes, August 13, 2015 (http://www.forbes.com/sites/federicoguerrini/2015/08/13/the-uk-will-be-trialling-roads-that-wirelessly-recharge-your-electric-car-while-you-drive/, accessed January 6, 2016); Scania Group, “Scania to test wirelessly charged city bus for the first time in Sweden,” press release December 17, 2014 (http://www.scania.com/media/pressreleases/N14050EN.aspx. accessed January 6, 2016); and Neil Bowdler, “Wirelessly charged electric buses set for Milton Keynes,” BBC News, January 9, 2014 (http://www.bbc.com/news/technology-25621426, accessed January 6, 2016).
- 22.
The size and weight of the pickup unit mounted on an OLEV vehicle should be able to be reduced so that the weight drops from 400 lb to about 100—perhaps by laminating thin layers of ferrite to get rid of eddy current fields and skin effects. (This is pure speculation at this point, not based on firm physics.) Meanwhile, we can do a rough lower-bound estimate of the cost of EVs and EGTS. We will assume that there are six billion people on earth and one billion cars on the road. If we assume that cars are used for ten years, we will have to replace 100 million cars a year. If we further assume that the cost of the battery in each EV is $1000, we will be spending $100 billion a year on batteries. If we assume that the infrastructure for EGTS lasts six years, each year we could invest $600 billion for infrastructure rather than in batteries. The need for additional cost-benefit analysis for OLEV is discussed in Chap. 16.
- 23.
The production cost of airplanes decreases by 10% each time the production volume doubles. Assuming a similar pattern in bus production, if Korea were to produce 1000 OLEV buses a year, the cost of the buses would be reduced by 65%. The U.S. market for buses in 2012 was around 74,000 [3]. Using the same mass production algorithm, we would expect a similar reduction in manufacturing cost. Mass production of key components of the ground transportation system, including buses, inverters, and ferrite cores, could reduce the cost per component by two-thirds (Willcox 2004). Overall, I believe that the cost of the components that go into OLEV and EGTS will decrease by 50% or more if demand increases sufficiently. The price for the ferrite core, for example, should come down through redesign and more R&D when demand for the product increases.
- 24.
Vimmerstedt et al. “Transformative Reduction of Transportation Greenhouse Gas Emissions: Opportunities for Change in Technologies and Systems,” National Renewable Energy Laboratory/U.S. Department of Transportation (NREL/TP-5400-62943 April 2015), p. 72. For an analysis of how EV penetration will be affected by choices made about plug-in versus online infrastructure, see Chap. 22.
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Suh, N.P., Cho, D.H. (2017). Wireless Power Transfer for Electric Vehicles. In: Suh, N., Cho, D. (eds) The On-line Electric Vehicle. Springer, Cham. https://doi.org/10.1007/978-3-319-51183-2_2
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