The comeback of the trackless trolley
The trackless trolley - or the trolleybus as it is called in Europe - is scheduled for a comeback.
The diesel bus emit carcinogenic particulates which may account for several thousands of cancer deaths in major cities. It is true that recent developments of emission technology has reduced the toxic emissions, but diesel exhaust is still the major contributor to high levels of nitrogen oxides and fine particulates in city centers.
Ethanol and natural or bio gas can also fuel buses, but the use of ethanol and gas fuels will also contribute to the environmental impact. Extensive production of ethanol from sugar cane in countries like Brazil is a danger to the rainforests. Natural or biogas is to 95-98% constituted of methane. Part of the methane is emitted and methane emissions are a powerful contributor to global warming since the 'greenhouse effect' is 17-20 times higher than that of carbon dioxide, CO2.
Electricity can be produced without emissions from a variety of sources like hydro, wind and nuclear. A comeback for nuclear energy - as suggested by Pres. Bush recently - will increase the odds of the trackless trolley as a means of transportation in the big cities.
Trackless trolleys are cheaper to install than light rail and other rail systems. They can be included in a 'Bus Rapid Transit' scheme with segregated busways.
They survive in 7 North American cities, and several hundred European. Once they were introduced as substitutes for streetcars in many cities.
San Francisco has the most extensive network of trackless trolleys in North America. It is constantly being extended, and is comprised by 17 lines. In addition to the trackless trolleys, San Francisco has several other environmentally sound transportation systems like cable cars, light rail, streetcars, subways and commuter rail. All the electric energy consumed by the trackless trolleys in SF comes from hydroelectric power - a clean energy source without any harmful emissions.
Seattle has a smaller network of trackless trolleys. Other cities in the US with trackless trolleys include Dayton, Boston and Philadelphia. Philadelphia recently decided to invest in new trackless trolleys in their southern suburbs where traffic was suspended for a number of years.
In Canada, Vancouver has an extensive network of trackless trolleys. The city of Vancouver also recently decided to invest in a large batch (more than 200) of new trackless trolleys of a futuristic design, and the first buses are delivered right now. Edmonton is the other Canadian city with trackless trolleys. They will soon have to decide about the future for the system, but environmental groups are optimistic that the city will invest in new trackless trolleys of maybe the same kind as in Vancouver.
The trackless trolley is cheaper than diesel buses given that the traffic density is sufficient. The life span of a trackless trolley is about double that of a diesel bus. Even if a trackless trolley is more expensive to buy due to the few items produced the capital costs as well as the running costs are lower. A trackless trolley uses about 2 kwh/km of electric energy compared to 0.5 liters of diesel per km for a diesel bus. In especially Europe, this means much lower energy costs for the trackless trolley.
So, when diesel prices are expected to rise further, while gas and ethanol prices also are high, the trackless trolley might be an environmentally attractive alternative for more and more cities sized 50.000 inhabitants and up. This is true both for North America and for Europe.
Bo Persson
The diesel bus emit carcinogenic particulates which may account for several thousands of cancer deaths in major cities. It is true that recent developments of emission technology has reduced the toxic emissions, but diesel exhaust is still the major contributor to high levels of nitrogen oxides and fine particulates in city centers.
Ethanol and natural or bio gas can also fuel buses, but the use of ethanol and gas fuels will also contribute to the environmental impact. Extensive production of ethanol from sugar cane in countries like Brazil is a danger to the rainforests. Natural or biogas is to 95-98% constituted of methane. Part of the methane is emitted and methane emissions are a powerful contributor to global warming since the 'greenhouse effect' is 17-20 times higher than that of carbon dioxide, CO2.
Electricity can be produced without emissions from a variety of sources like hydro, wind and nuclear. A comeback for nuclear energy - as suggested by Pres. Bush recently - will increase the odds of the trackless trolley as a means of transportation in the big cities.
Trackless trolleys are cheaper to install than light rail and other rail systems. They can be included in a 'Bus Rapid Transit' scheme with segregated busways.
They survive in 7 North American cities, and several hundred European. Once they were introduced as substitutes for streetcars in many cities.
San Francisco has the most extensive network of trackless trolleys in North America. It is constantly being extended, and is comprised by 17 lines. In addition to the trackless trolleys, San Francisco has several other environmentally sound transportation systems like cable cars, light rail, streetcars, subways and commuter rail. All the electric energy consumed by the trackless trolleys in SF comes from hydroelectric power - a clean energy source without any harmful emissions.
Seattle has a smaller network of trackless trolleys. Other cities in the US with trackless trolleys include Dayton, Boston and Philadelphia. Philadelphia recently decided to invest in new trackless trolleys in their southern suburbs where traffic was suspended for a number of years.
In Canada, Vancouver has an extensive network of trackless trolleys. The city of Vancouver also recently decided to invest in a large batch (more than 200) of new trackless trolleys of a futuristic design, and the first buses are delivered right now. Edmonton is the other Canadian city with trackless trolleys. They will soon have to decide about the future for the system, but environmental groups are optimistic that the city will invest in new trackless trolleys of maybe the same kind as in Vancouver.
The trackless trolley is cheaper than diesel buses given that the traffic density is sufficient. The life span of a trackless trolley is about double that of a diesel bus. Even if a trackless trolley is more expensive to buy due to the few items produced the capital costs as well as the running costs are lower. A trackless trolley uses about 2 kwh/km of electric energy compared to 0.5 liters of diesel per km for a diesel bus. In especially Europe, this means much lower energy costs for the trackless trolley.
So, when diesel prices are expected to rise further, while gas and ethanol prices also are high, the trackless trolley might be an environmentally attractive alternative for more and more cities sized 50.000 inhabitants and up. This is true both for North America and for Europe.
Bo Persson
posted by LH at
11:04 AM
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