CETE FAQs

There are a number of methods that can be followed to increase the amount of time an electric bus can be operated in service. The first is to perform battery change outs. Many systems, including Chattanooga, regularly swap battery packs. In a span of 10-15 minutes, the bus can be back in service.

The second way to increase the amount of time an electric bus can be operated is to fast charge the batteries. Several research projects are underway utilizing this process. The Cape Cod National Sea Shore utilizes a fast charger on their trams to keep them running throughout the day.

Another method for increasing the amount of time an electric bus can be operated is to purchase advanced technology batteries, such as nickel-cadmium batteries. Although much more expensive, ni-cads can double the range of electric buses and have a longer life span than conventional lead-acid batteries.

A final method for increasing the amount of time an electric bus can be operated is to integrate an auxiliary power unit (or APU) on the bus for range extension. By utilizing a second fuel and an engine/generator, electricity can be created that can significantly add to the range of the bus. Electric vehicles that use two fuels are referred to as "hybrids"

Do electric buses have transmissions?

Can cells in a battery pack be replaced?

Is an electric vehicle more energy efficient than an ICE vehicle?

The 22-foot bus, which is the predominant electric bus in operation today, is governed around 45 miles per hour. The 40-foot hybrid-electric bus operating in New York is governed at 55 miles per hour.

It should be noted that "fuel" costs can vary based on battery size and/or the efficiency of the battery charger, along with local electricity costs of course.

There are three different types of hybrids; series, parallel, and dual-mode. Today, most of the hybrid-electric buses are series hybrids with propulsion power coming from the batteries with the engine/generator fueling the batteries. Most of the hybrid automobiles, however, are parallel hybrids; the vehicle can be moved by either the batteries or the engine; whatever is most efficient.

A third type of hybrid is emerging, one that will operate on both the batteries and the engine at the same time. This is referred to as a dual-mode hybrid.

Energy draw for air-conditioners and heaters is more significant. Therefore, many electric buses do operate the AC and heat through a separate system that is powered by an alternative fuel such as compressed natural gas or propane. There are a number of efforts underway to produce low energy and high efficient air-conditioning systems.

Although electric buses are more expensive to purchase than comparable sized diesel buses, remember that the cost of fueling the bus is significantly less. Additionally, because there are fewer components and daily maintenance is normally limited to batteries, regular maintenance costs are also much lower. Thus, the life cycle cost of an electric bus (including purchase and operating costs) is, today, equal to or even lower than comparable diesel buses.

 Is special training required for drivers and mechanics?

Maintenance training on electric buses is extremely important. Electric buses are not any more complicated than buses with internal combustion engines, but they are different. An alternative fueled bus utilizes all of the same components as a diesel bus with the exception that the fuel is different (and some fuel delivery components). An electric bus utilizes a propulsion system that is unlike any other motor vehicle. Thus, understanding the unique elements of electric propulsion systems is critical to ensure dependable operation.

  Can electric buses operate up hills?

A charge non-sustaining hybrid utilizes a generator that may or may not maintain the batteries, depending on the application. Thus, if the bus runs out of the fuel necessary to operate the APU, and the batteries are depleted, the bus will not operate, even if more fuel for the APU is added.

AC and DC motors come in different sizes with different torque curves. As each have different characteristics and advantages, it is important to discuss the types propulsion systems available during the purchase of an electric bus.

And, of course, power plants are not located where people live and work. Additionally, it is easier to scrub for emissions at the relatively low number of power plants then the millions of motor vehicles traveling our streets.

It should be noted that the way the electricity is created will play a major role in determining this percentage. Clearly, power generated from water or wind will result in a 100% reduction in emissions.

And one other point must be made. Power plants which operate on coal or similar types of fuels have made great strides to reduce emissions. It is much easier to maintain and police the few power plants then the millions of cars, trucks, buses, etc., used by the public.

What is better...conductive charging or inductive charging?

Conductive chargers are used by many other automobile manufacturers and use the more traditional electrical plug concept.

For electric vehicles to become more viable, a single type of charging connection will need to be agreed on.