Archive for the ‘Buses’ Category

KAIST (Korea Advanced Institute of Science and Technology) has replaced a ICE (Internal Combustion Engine) train that runs inside Seoul Grand Park in Gwacheon City with an online electric vehicle (OLEV).  The EV bus gets power from cables that are buried underground through a non-contact magnetic charging method, called electromagnetic induction. The OLEV receives electricity when it passes over the cables and that power can be used to operate the vehicle or charge the batteries.  This electric vehicle proves that there is no need to create charging stations, schedule time for recharging batteries or even equipping EVs with large banks of batteries.  This particular OLEV only has about 1/5th of the batteries typically installed in electric vehicles.  It is estimated that a city could have a viable environmentally friendly all electric public transportation system by strategically installing the underground power cables at particular: curbs, bus stops, parking lots, and intersections along approximately 20% of any bus route to power one of these electric buses.

This technology solves many of the battery issues that relate to EVs such as: expense, charging time, maintenance and general size and quantity requirements.  This non-contact method of powering EVs is safer because it eliminates electric shock hazards that are possible with overhead wire streetcar and tram systems.

The recharge strips are several meters in length and feature a sensor that basically operate as an on/off switch for the power transfer for a properly equipped EV bus or car.

KAIST’s OLEV research team has previously demonstrated that their system can have a 70% efficiency level of power transmission with a air-gap of 12 cm (and up to 17 cm).  The KAIST system proves the viability of electric vehicles for commercial use by making major advances in terms of capacity and efficiency of wireless powered roadway systems.  They have also been able to get the electromagnetic field (EMF) of their system well below the international standard of 62.5mG.

The particular OLEV (one engine and three passenger cars) at the Seoul Grand Park has a electric pick-up capacity of 62kw/h using an air-gap height of 13 cm from a road to the bottom of the vehicle, which translates to a 74% energy transfer efficiency. The system is functioning well with underground power supply cables only covering 16% of the total route.

Even though it may take a few years for individual consumers to start buying EVs and hybrids en masse, manufacturer’s are currently finding that their best customers are green fleet buyers for various large businesses and city/municipalities eager to even pay a premium to switch over to cleaner/greener more efficient models. One reason for this is that EVs and many hybrid designs eliminate the need for a mechanical transmission which means no expensive transmission overhauls, a major maintenance item on conventional city and mass transit buses. In addition for EV’s they can also eliminate oil changes, differential/transfer case service, fuel injection service, maintenance/inspection of timing belts, starting systems, and proper exhaust and clutch operation.  They can also permanently omit the standard periodic replacement of transmission fluid, spark plugs, air filters and fuel filters.

With such maintenance cost benefits especially when computed over the life of the vehicle it’s not surprising for instance that Daimler Buses North America (from Riskany N.Y. and Mississauga, Ontario) recently announced that sales for their diesel-electric hybrid buses have surpassed 3,000 units and they have an additional 850 firm orders from cities such as New York City, Seattle, Houston, Ottawa and Puerto Rico. Their Orion hybrid buses use lithium-ion energy storage technology, which reduced the weight of the overall bus and thereby further improving fuel economy. Their buses also feature regenerative braking systems that uses the electric drive motor to slow the bus, effectively turning the motor into a generator to help recharge the bus batteries and significantly reduces brake wear.

US based telecom giant AT&T  says it plans to develop a fleet of more than 15,000 alternative-fuel vehicles over the next 10 years and more recently the Florida energy firm FPL Group and Duke Energy announced that they would transition their entire fleets – totalling over 10,000 vehicles to low carbon EV and hybrid models.