Streetcar Technology. Today the definition of these terms is becoming. Mexico Horse Drawn Streetcar. Wilbur Smith Associates. Streetcar Technology

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1 What is in a name? Are streetcars, trams, trolleys and light rail all the same or are they different? Definitions tend to be a little blurred for these terms. In general, streetcars are rail borne vehicles which at least in part operate within a public street right of way. They are not necessarily electric powered, but most streetcars are electric powered. Trams are generally the same as streetcars, but sometimes cable cars are included as trams. Trolleys historically derived their name from the term troll (as in trolling for fish). The first electric streetcars obtained their power from an overhead catenary line via a rooftop cable pulling a shoe collector, which used gravity, to maintain contact with the catenary wire. Thus, the streetcars appeared to be trolling for electricity. Later versions of electric trolleys used a pole rather than cable and applied spring pressure to the pole to pick up power from the bottom of the overhead wire. Light rail is a more recent term and is generally used to describe transit vehicles with lower capacities and speeds than passenger rail and urban metro systems and which primarily operate in exclusive rights of way, but often with some in street running sharing traffic lanes. Today the definition of these terms is becoming Mexico Horse Drawn Streetcar more muddled as alternative propulsion systems are coming to the market. The broad generic term streetcar however continues to encompass most options potentially of interest to Fresno. Streetcars differ in style, performance, propulsion and costs. Styles of Streetcars There are two basic styles of streetcars and two categories within each of these styles. The two basic styles are historic and modern. Historic streetcars include refurbished vintage cars and replica cars. The former are not air conditioned and lack some modern amenities (on board passenger information technologies etc.). They typically require stops to have ADA compliant mini high platforms to board wheelchair passengers. The replica cars appear similar to the vintage streetcars, but are built new and can be air conditioned. Examples of the vintage streetcar include the Market Street Streetcar in San Francisco which uses refurbished streetcars from around the world Melbourne, Milan, Zurich, England and from around the USA San Francisco, Philadelphia, St Louis, Birmingham, New Orleans, Baltimore etc. Vintage streetcars include double deck cars (Hong Kong) and systems pulling a non powered trailer car behind 1

2 the main powered streetcar (Christchurch NZ). Replica operations include Tampa, New Orleans (Riverfront Line), Little Rock and Galveston. Modern streetcars include light rail vehicles and smaller trams. Examples of light rail include Sacramento, San Diego, San Francisco MUNI and Denver. Examples of modern streetcars include the South Lake Union Trolley in Seattle, Tacoma Streetcar and the Portland Streetcar Line (Portland also operates a historic trolley and light rail). cars and replica cars. The former are not air conditioned and lack some modern amenities (on board passenger information technologies etc.). They typically require stops to have ADA compliant mini high platforms to board wheelchair passengers. The replica cars appear similar to the vintage streetcars, but are built new and can be air conditioned. Examples of the vintage streetcar include the Market Street Streetcar in San Francisco which uses refurbished streetcars from around the world Melbourne, Milan, Zurich, England and from around the USA San Francisco, Philadelphia, St Louis, Birmingham, New Orleans, Baltimore etc. Vintage streetcars include double deck cars (Hong Kong) and systems pulling a non powered trailer car behind the main powered streetcar (Christchurch NZ). Replica operations include Tampa, New Orleans (Riverfront Line), Little Rock and Galveston. Modern streetcars include light rail vehicles and smaller trams. Examples of light rail include Sacramento, San Diego, San Francisco MUNI and Denver. Examples of modern streetcars include the South Lake Union Trolley in Seattle, Tacoma Streetcar and the Portland Streetcar Line (Portland also operates a historic trolley and light rail). Light rail vehicles tend to be 100 feet long and are often combined into trains more than 200 feet in length. Modern trams like those deployed in Portland, Tacoma and Seattle are about 66 feet in length. The trams also are Washington Historic Poleless Streetcar Memphis Vintage Streetcar San Francisco Blackpool England Boatcar 2

3 slightly narrower (six inches) than conventional light rail and buses. The 66 foot length is comparable to the length of modern articulated buses (bend in the middle buses). Vintage and replica trams are about 40 to 50 feet in length. Most seat about 40 passengers. Propulsion systems range from horses/mules to flywheel powered and include steam, overhead electric power, underground electric power and diesel. The horsecart systems evolved from omnibus (horse drawn passenger vehicles on roads) with the street rails reducing the rolling resistance and allowing horses to pull larger passenger carts. The rails also provided a smoother ride than the potholed and rutted streets. A few cities opted for steam propelled streetcars either with a tug pulling unpowered carts or with powered passenger carts. Shortly, before the San Francisco PCC Streetcar Tampa Replica Streetcar Christchurch New Zealand Streetcar Trailer 3

4 Tacoma Modern Streetcar Modern Portland Tram beginning of the 20th Century Frank Sprague developed the electric streetcar technology that was widely applied and continued to be popular until about World War II. The electric powered streetcars depended on a single overhead power wire (catenary). Historically trials were also conducted for petrol driven streetcars (Stockholm) and compressed air (Paris). Some of the new propulsion technologies on the market today are hybrids using both conventional overhead electric power to supplement the new technology power. Use of super capacitors and perhaps even fuel cells are on the horizon. Overhead Electric Power The overhead contact system (OCS) is the most common form of propulsion for vintage, replica, modern tram and light rail vehicles. It was the system employed on Fresno s former streetcar system. It is efficient, reliable and quiet. Some people, however, do not like the visual presence of the overhead wires and there are maintenance costs associated with maintaining the power distribution system. The vintage and replica streetcars typically collect the power from the overhead wire using a simple shoe UTA Trax Light Rail device attached to the end of the trolley pole. Modern trams and light rail vehicles more often use a pantograph V shaped collector with a flat bar contacting the wire. The power wire is typically 18 feet above the street and is held in place by span wire connected either to special poles along the curbfront or to eyebolts connected to adjacent buildings. Overhead wire is also sometimes suspended directly beneath special trolley poles located along the curbfront or in the street median. The technology has been 4

5 used for more than 120 years, can be inexpensive to build and maintain and the overhead can be effectively masked with urban design and sensitive engineering. Diesel Power Galveston constructed a diesel powered vintage streetcar system in The decision to use diesel power in lieu of conventional electric overhead power reportedly was to minimize hurricane weather related problems. The on-board diesel engines do not provide sufficient power for air conditioning and limit operating speeds. Diesel power has become increasingly less popular for bus transit operations due to clean air concerns. The Galveston streetcars operate relatively quietly. The car has four 40 horse power motors one for each axle. Maximum speed is 25 mph, but operating speeds are lower. Siemens has also developed a hybrid light rail system that can be powered by electric overhead catenary in urban settings and by diesel power in rural settings. It is in operation in Norhausen Germany. Galveston Diesel Powered Historic Streetcar Battery Power Most of these new systems are hybrids and also operate as conventional streetcars getting electric power from an overhead wire. Alstom has deployed battery light rail in Nice. Kawasaki is testing a battery powered streetcar in Sapporo. Siemens has also developed a battery streetcar system which has been deployed in Portugal.. TIG/m (Transportation Innovations Group) has been operating a battery powered trolley since 2002 at a Los Angeles area shopping mall (The Grove at Farmers Market). The theme cars are specially built using PCC wheel trucks. They are double deck cars with a top speed of 8 mph. The cars operate 8 to 10 hours a day with full charging of batteries Nice Battery Powered Modern Streetcar Kawasaki Battery Powered Modern Streetcar 5

6 Siemens Modern Streetcar overnight and end of line layover charging and regenerative braking charging during the operating day. Unlike the Kawasaki and European systems, the TIG/m system only operates on battery and does not operate with overhead power. Other American applications have proposed battery replica systems in Puerto Los Cabos Mexico (vehicle in production), Polo Square Indio CA. Eilan San Antonio TX (vehicle in production). Alstom s Nice light rail system, which has been in service since 2007 allows a 1km run using the nickel metal hydride batteries. Current application is understood to involve short segments of battery running (about 100m). Batteries are fully rechargeable after about 20 minutes of operation using conventional overhead catenary power. The Siemens system, which is branded Sitras HES, reportedly can operate up to 2500m on battery power before needing to connect to overhead catenary power. It uses two energy storage devices (a double layer capacitor and a nickel hydride battery. Double layer capacitors also sometimes known as Super or Ultra Capacitors are used by the military to start tanks and submarine engines. The Siemens system uses a short double articulated light rail vehicle (estimated at 100 feet in length). Kawasaki s SWIMO system claims to allow a 10km battery run with a five minute charge. SWIMO uses nickel metal hydride batteries. Grove at Farmer s Market Battery Streetcar Kawasaki is also investigating a nickel hydrogen battery that recharges in only ten seconds and allows for recharging at passenger platform power docks. Savannah s streetcar system, which started in February 2009 is a vintage sytem that uses super capacitor technology along with batteries to operate without overhead power wires. The system was developed by Electric Motor and Supply in Altoona (Buy America) and can also operate with overhead power. Recharging batteries occurs at the end of the line. Seville Spain is in the process of deploying a super capacitor light rail system which will operate for about one mile without overhead catenary power supply. Granada and Zaragoza Spain are also planning on operations without overhead wires for segments of service. The Spanish 6

7 systems require about 20 seconds to charge the super capacitors. Underground Power Historically an underground third rail was employed for power in Washington DC and Brooklyn for streetcars. A slot between the running rails was used to pick up power from the underground third rail. More recently Alstom installed a hybrid underground power light rail system in Bordeaux France. Bombardier has also been testing hybrid underground light rail systems. The underground power is used in visually sensitive areas to complement conventional overhead power sections on other parts of the line. The Bordeaux system uses retractable collector shoes to obtain power from the underground third rail. It has been in operation since 2003 and encountered maintenance issues, particularly in its first years of service. Full size light rail trainsets are used for this service. The Bombardier system being tested in Bautzen Germany is a contactless system with the underground third rail energized only when the train is overhead. The Bombardier system, which is branded as PRIMOVE, relies on electromagnetic fields released from buried cables (inductive power) located under the rail tracks. The technology uses full size light rail trainsets. Savannah Streetcar Bordeaux Modern Streetcar Flywheel Power Alstom has installed a flywheel powered tram in Rotterdam. The flywheel power augments the overhead catenary powered line for a short section traversing a new bridge. The flywheel system uses a carbon fibred rotating permanent magnet motor-generator located on the tram roof. Kinetic energy is stored during braking. Full size light rail trainsets are used in Rotterdam for the poleless segment. Bombardier Modern Streetcar 7

8 Rotterdam Modern Streetcar Summary A wide range of technologies are being explored to free streetcars from dependence on overhead power requirements. It should be noted that many streetcar advocates actually like the overhead wire and the traditional streetcar technology. Most of the new technologies are more costly and less proven than conventional streetcar technologies. Most of the poleless systems also are hybrids that run using overhead power for most of the line, but switch to battery or underground power for short segments of the line. The new off wire technologies can tend to limit running speeds and require larger trainsets. Buy American rules associated with federal funding also are a factor for imported systems. Most recent streetcar projects have used modern tram technology (Portland, Seattle and Tacoma) and several have used special built technologies like Savannah and private development sponsored systems in development for Texas and Mexico. The latter probably could not operate on public streets. Hong Kong Double Deck Streetcar modern Portland type trams. Portland Ironworks makes the trams and would be consistent with Buy American Rules. Vintage and replica cars could also comply. The modern tram s advantages are its air con, better ADA compliance and high possible speeds. Trams are available in low floor designs. Overhead wire is not likely to be a huge issue in Fresno. The technology options therefore primarily are vintage/replica style cars versus 8