For the alternative name for a sack truck (trolley truck), see Hand truck
A trolleytruck (also known as a freight trolley or trolley truck) is a trolleybus-like vehicle used for carrying cargo instead of passengers. A trolleytruck is usually a type of electric truck powered by two overhead wires, from which it draws electricity using two trolley poles or two pantographs. Two current collectors are required in order to supply and return current, because the return current cannot pass to the ground (as is done by streetcars on rails) since trolleytrucks use tires that are insulators. Lower powered trucks, such as might be seen on the streets of a city, tend to use trolley poles for current collection. Higher powered trucks, such as those used for large construction or mining projects, may exceed the power capacity of trolley poles and have to use pantographs instead. Trolleytrucks have been used in various places around the world and are still in use in cities in Russia and Ukraine, as well as at mines in North America and Africa.
Use throughout the world
Trolleytrucks were used in Gümmenen and Mühleberg Switzerland between 1918 and 1922 during the construction of the dam that retains Lake Wohlen. The trucks were built by Tribelhorn, and they used the Stoll system of current collection.
Trolleytrucks were used by the AEM electric utility company of Milan, Italy to supply construction materials and service to the San Giacomo Dam (constructed 1940-1950) and the second Cancano Dam (constructed 1952-1956). The two trolleytruck lines in the Valtellina valley that helped to build then supply the dams along the Spöl river were used from 1938 to 1962.
Trolleytrucks were used in St. Lambrecht, Austria by the Nobel Industries dynamite factory from 16 November 1945 to 21 April 1951. Trolleytrucks were used to carry dynamite over the Alps just after World War II due to the shortages of material that for a time prevented the use of diesel trucks. In the 1950s the material shortages had been alleviated so the trolleytrucks were replaced with diesel trucks and the former power lines were taken down. Some trucks from the abandoned line were reconverted to passenger trams and used along streets in Kapfenberg.
From 1939 to 1964 the International Salt Company mine in River Rouge, Michigan used trolleytrucks that were converted Euclid 20 short tons (18 t) models. This was an underground salt mine. Batteries were used to power the trucks when they strayed away from the overhead wires. For use within a mine the overhead wires may occasionally be relocated as excavation activity progresses. Hence the trolleytrucks used in mines do not necessarily have a travel route that is as fixed as the trolleytruck routes used in cities.
From 1956 to 1971 the Riverside Cement Company in Bloomington, California operated Kenworth 30-short-ton (27 t) dump trucks converted to trolleytruck use at the Crestmore Quarry near Riverside, California. The trucks were equipped with "extension cords" for use of electric power near the shovel down in the mine. The long extension cords stored on powered reels aboard the trolleytrucks offered them increased mobility right at the load point.
In 2015, a demonstration phase will start for an eHighway system in the area served by the Port of Los Angeles and Port of Long Beach. Initially, the eHighway will be a one-mile two-way stretch of road on the north- and south-bound sections of Alameda Street where it intersects with Sepulveda Boulevard in Carson, California. Construction of the system is expected to start immediately, and the first trucks should connect to the system in July 2015. When the trucks aren’t travelling the eHighway, they can run on diesel, compressed natural gas (CNG), battery or other energy source. They are build by Mack Trucks in cooperation with Siemens. The demonstration phase is scheduled to last for one year. 
The El Chino Mine near Santa Rita, New Mexico installed trolleytrucks in 1967. The trucks are equipped with diesel engines and the trolley power is used to assist the trucks up and down the ramp that leads into the mine. This type of double power arrangement is known as a trolley assist system.
Barrick's Goldstrike mine, Nevada used trolleytrucks from 1994 to 2001 when the trolley system was decommissioned due to a large reconfiguration of the mine. The system was similar to the one used in the Palabora copper mine in South Africa.
Soviet Union, Russia, Ukraine
Many cities in the Soviet Union operated trolleytrucks. The MAZ-525 truck model was converted to a trolleytruck design in 1954 in Kharkiv, Ukraine. The Kharkiv experiment with trolleytrucks was stopped because of disadvantages.
Nowadays trolleytrucks operate in several cities in Ukraine such as Donetsk and Sevastopol as well as cities in Russia such as Bryansk and Saint Petersburg. One type, the KTG-1, is made for service and repair of the urban trolleybus vehicles; while another, the KTG-2, is used for transporting goods.
Trolleytruck KTG-1 in St. Petersburg, Russia in 2006
The Québec Cartier Mining Company used trolleytrucks in its iron ore mine in Québec from 1970 until 1977 when the iron ore deposit was exhausted and the mine closed down. Interestingly, the power supply for this remote mine was a power plant taken out of a diesel electric railroad locomotive.
The South African Iron and Steel Industrial Corporation (ISCOR) installed a 7.7 kilometres (4.8 mi) trolley power assist line for 170 short tons (150 t) diesel electric trucks at its Shishen mine in March 1982. Afterwards the company also installed a trolley power assist system at its Grootegeluk coal mine in Lephalale, South Africa. ISCOR (now known as Mittal Steel South Africa) is the largest user of trolley power assist trolleytruck systems in the world.
Trolleytrucks were used in the Zambia Consolidated Copper Mines Nchanga Mine in Zambia from 1983 until later in the 1980s. Inexpensive hydroelectricity is generated at the Kariba Dam along the Zambezi river and distributed throughout the "copper belt" of Zambia. The current delivery for the trolley power assisted diesel trucks (120 short tons (110 t)) was done through custom designed bus bars and large current collection shoes mounted on very large trolley pole-like collectors.
The Rössing Uranium Mine mine in Namibia installed a trolley assist system around 1986. The diesel electric drive Komatsu 730E dump trucks were converted at that time to use trolley power assist for the climb out of the mine to the crusher. The fleet numbered more than 10 vehicles as of 2001.
- In the United Kingdom a trolley may refer to the hand operated wheeled vehicle called a hand truck in North America. In North American usage the term trolley truck may also be used to refer to the wheelset or bogie that a streetcar rides upon.
- Trams may collect current from a single wire with a single trolley pole or pantograph and return the current to earth via the rail.
- "Siemens History - Industry & Automation". 2009-01-12.
- Dave Hutnyak. "Trolley History". Hutnyak Consulting. Retrieved 2009-01-12.
- "A2A - Cancano Dam". Retrieved 2009-01-12.[dead link]
- "A2A - San Giacomo Dam". Retrieved 2009-01-12.[dead link]
- "A2A - AEM". Retrieved 2009-01-12.[dead link]
- "Trolleytrucks". Retrieved 2009-01-10.
- Wolfgang Auer. "St. Lambrecht Trolley-truck Line". Retrieved 2009-01-10.
- "Kenworth Trolleytruck in Seattle, Washington; May 1956". Retrieved 2009-01-04.
- The Riverside Cement Company was sold to the SsangYong Group which then sold Riverside Cement to Texas Industries.
- Dave Hutnyak's "Trolley History" page mentions that Kennecott Utah Copper operated the "Chino" mine in New Mexico in the 1960s. Note that the mine is now owned by Freeport-McMoRan.
- "Trolley Overview". Retrieved 2009-01-13.
- "Barrick Gold Corporation - Global Operations - North America - Goldstrike Property". Retrieved 2009-01-13.
- "Sevastapol-TG104.JPG". Retrieved 2009-01-10.
- "Palabora Mining Company". Retrieved 2009-01-13.
- "ISCOR Mining, South Africa - 1982 to 2001". Retrieved 2009-01-13.
- "Pleven and its trolleybus system - The trolleybuses of Pleven, Bulgaria". Retrieved 2009-01-13.
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