A dual-mode bus is a

bus A bus (contracted from omnibus, with variants multibus, motorbus, autobus, etc.) is a motor vehicle that carries significantly more passengers than an average car or van, but fewer than the average rail transport. It is most commonly used ...

that can run independently on power from two different sources, typically electricity from

overhead lines An overhead line or overhead wire is an electrical cable that is used to transmit electrical energy to electric locomotives, Electric multiple unit, electric multiple units, trolleybuses or trams. The generic term used by the International Union ...

like a

trolleybus A trolleybus (also known as trolley bus, trolley coach, trackless trolley, trackless tramin the 1910s and 1920sJoyce, J.; King, J. S.; and Newman, A. G. (1986). ''British Trolleybus Systems'', pp. 9, 12. London: Ian Allan Publishing. .or troll ...

or from batteries like a

hybrid bus A hybrid electric bus is a bus that combines a conventional internal combustion engine ground propulsion, propulsion system with an electric power, electric propulsion system. These types of buses normally use a diesel–electric powertrain and ...

, alternated with conventional

fossil fuel A fossil fuel is a flammable carbon compound- or hydrocarbon-containing material formed naturally in the Earth's crust from the buried remains of prehistoric organisms (animals, plants or microplanktons), a process that occurs within geolog ...

(generally

diesel fuel Diesel fuel, also called diesel oil, heavy oil (historically) or simply diesel, is any liquid fuel specifically designed for use in a diesel engine, a type of internal combustion engine in which fuel ignition takes place without a spark as a re ...

). In contrast to other hybrid buses, dual-mode buses can run forever exclusively on their electric power source (wires). Several of the examples listed below involve the use of dual-mode buses to travel through a tunnel on electric overhead power. Many modern trolleybuses are equipped with auxiliary propulsion systems, either using a small

diesel engine The diesel engine, named after the German engineer Rudolf Diesel, is an internal combustion engine in which Combustion, ignition of diesel fuel is caused by the elevated temperature of the air in the cylinder due to Mechanics, mechanical Compr ...

or battery power, allowing movement away from the overhead wires, called "off-wire" movement, but such vehicles are generally not considered to be dual-mode buses if their off-wire capability is very limited. Examples include the fleet of about 300 trolleybuses in

San Francisco San Francisco, officially the City and County of San Francisco, is a commercial, Financial District, San Francisco, financial, and Culture of San Francisco, cultural center of Northern California. With a population of 827,526 residents as of ...

and the trolleybuses used on a 2005-opened system in

Rome Rome (Italian language, Italian and , ) is the capital city and most populated (municipality) of Italy. It is also the administrative centre of the Lazio Regions of Italy, region and of the Metropolitan City of Rome. A special named with 2, ...

, Italy,Webb, Mary (ed.) (2009). ''Jane's Urban Transport Systems 2009-2010'', p. 195. Coulsdon (UK):

Jane's Information Group Janes is a global open-source intelligence company specialising in military, national security, aerospace and transport topics, whose name derives from British author Fred T. Jane. History Jane's Information Group was founded in 1898 by Fred T. ...

. . which are capable of running on battery power only for short distances or short periods of time before needing recharging. The Rome vehicles are powered from overhead trolley wires over most of the 11.5-km route and only use battery power on the 500-metre section closest to the city centre. Dual mode trolleybuses in a number of Chinese cities can operate significant distances (8 to 10 km) off-wire on battery power.

Examples

Beijing Beijing, Chinese postal romanization, previously romanized as Peking, is the capital city of China. With more than 22 million residents, it is the world's List of national capitals by population, most populous national capital city as well as ...

China China, officially the People's Republic of China (PRC), is a country in East Asia. With population of China, a population exceeding 1.4 billion, it is the list of countries by population (United Nations), second-most populous country after ...

uses a fleet of over 1,250 dual-mode trolleybuses for its trolleybus network. * Bergen, Norway features dual-mode MAN-Neoplan buses in the Bergen trolleybus system *

Boston Boston is the capital and most populous city in the Commonwealth (U.S. state), Commonwealth of Massachusetts in the United States. The city serves as the cultural and Financial centre, financial center of New England, a region of the Northeas ...

, Massachusetts, USA installed dual-mode Neoplan DMA-460LF buses on the Waterfront portion of its Silver Line in 2005 and removed in 2023. Electric power was required in the exclusive right of way that runs in a tunnel under Fort Point Channel to South Station; diesel power was used to run on city streets and highways, including the Ted Williams Tunnel to Logan Airport *

California California () is a U.S. state, state in the Western United States that lies on the West Coast of the United States, Pacific Coast. It borders Oregon to the north, Nevada and Arizona to the east, and shares Mexico–United States border, an ...

MUNI's

30 Stockton 30 Stockton is a trolleybus line operated by the San Francisco Municipal Railway. The line is notable for being the slowest trolleybus route in the city of San Francisco because it travels through the densely populated neighborhood of Chinatown, ...

uses battery power on a short section of the route, and trolleybus power on the rest of it. *

Castellón de la Plana Castellón de la Plana (in ), or simply Castellón (), is the capital city of the province of Castellón, in the Valencian Community, Spain. It is located in the east of the Iberian Peninsula, on the Costa del Azahar by the Mediterranean Sea. Th ...

, Spain installed a new trolleybus line that went into operation 25 June 2008. The Irisbus Civis vehicles are optically guided and are capable of switching to diesel engine power for turning in front of the Parque Ribalta. *

Seattle, Washington Seattle ( ) is the List of municipalities in Washington, most populous city in the U.S. state of Washington (state), Washington and in the Pacific Northwest region of North America. With a population of 780,995 in 2024, it is the List of Unit ...

, USA used 236 dual-mode Breda ETB buses in its downtown bus tunnel from 1990 until late 2004, when the fleet of dual-mode buses were retired, except for 59 converted to electric-only service and were replaced in the tunnel by hybrid diesel-electric buses. *

Shanghai Shanghai, Shanghainese: , Standard Chinese pronunciation: is a direct-administered municipality and the most populous urban area in China. The city is located on the Chinese shoreline on the southern estuary of the Yangtze River, with the ...

uses a fleet of over 300 dual-mode trolleybuses for its network. *

Ploiești Ploiești ( , , ), formerly spelled Ploești, is a Municipiu, city and county seat in Prahova County, Romania. Part of the historical region of Muntenia, it is located north of Bucharest. The area of Ploiești is around , and it borders the Ble ...

Romania Romania is a country located at the crossroads of Central Europe, Central, Eastern Europe, Eastern and Southeast Europe. It borders Ukraine to the north and east, Hungary to the west, Serbia to the southwest, Bulgaria to the south, Moldova to ...

features ex-Lausanne Neoplan N6121 dual-mode buses in the Ploiești trolleybus system. *

São Paulo São Paulo (; ; Portuguese for 'Paul the Apostle, Saint Paul') is the capital of the São Paulo (state), state of São Paulo, as well as the List of cities in Brazil by population, most populous city in Brazil, the List of largest cities in the ...

Brazil Brazil, officially the Federative Republic of Brazil, is the largest country in South America. It is the world's List of countries and dependencies by area, fifth-largest country by area and the List of countries and dependencies by population ...

also has a dual bus that operates in the Jabaquara district, in the south zone. One of these is a Superarticulated Bus that operates in the Corredor ABD. *

Gdynia Gdynia is a city in northern Poland and a seaport on the Baltic Sea coast. With an estimated population of 257,000, it is the List of cities in Poland, 12th-largest city in Poland and the second-largest in the Pomeranian Voivodeship after Gdańsk ...

and

Lublin Lublin is List of cities and towns in Poland, the ninth-largest city in Poland and the second-largest city of historical Lesser Poland. It is the capital and the centre of Lublin Voivodeship with a population of 336,339 (December 2021). Lublin i ...

, both

Poland Poland, officially the Republic of Poland, is a country in Central Europe. It extends from the Baltic Sea in the north to the Sudetes and Carpathian Mountains in the south, bordered by Lithuania and Russia to the northeast, Belarus and Ukrai ...

have the dual-mode buses running as part of their

networks Network, networking and networked may refer to: Science and technology * Network theory, the study of graphs as a representation of relations between discrete objects * Network science, an academic field that studies complex networks Mathematics ...

, in case of Gdynia, their (PKT's) duobuses are Solaris Trollinos and Mercedes Citaros (which were converted into trolleybuses in 2012). Both of these types, unlike typical dual-mode buses, are trolleybus and

electric bus An electric bus is a bus that is propelled using electric motors, as opposed to a conventional internal combustion engine. Electric buses can store the needed electrical energy on board, or be fed mains electricity continuously from an external ...

hybrids.

References

External links

{{Buses Buses by type ja:バス (交通機関)#その他の特殊なバス

Examples

See also

References

External links