Light metro

Some trains are in the middle.

They carry more people than a bus. But they carry fewer people than big city trains. These trains use short cars. They also use small stations.

These trains stay on their own tracks. They do not cross paths with cars. This keeps them safe and fast. Some of these trains have no driver. A computer moves them instead.

Because the trains are light, they can go fast. They can speed up and slow down quickly. This helps people get to where they are going. They are a smart way to move many people.

A light metro is a special way to move people.

It sits in the middle of two other systems. It carries more people than a light rail. But it carries fewer people than a big rapid transit system.

Light metros use shorter trains. These trains usually have only 2 to 4 cars. They also use smaller stations. This helps make the system cheaper to build.

These trains stay on their own tracks. They do not cross paths with cars or buses. This is called being grade separated. This keeps the trains safe and fast.

Some light metros use automatic train operation. This means a computer moves the train without a driver.

Because they are driverless, they can run very often. Some trains arrive every 90 seconds during busy times. This helps them carry many people.

Some systems use rubber tyres instead of metal wheels. This helps them make tight turns. It also makes less noise. The Taipei Metro uses this way to move people.

A light metro is a clever way to move people through a city.

It sits right in the middle of two other types of trains. It carries more people than a light rail system. However, it carries fewer people than a large rapid transit system. Planners use math to decide which system a city needs. They look at how many people will use the trains each day. If the number is between light rail and rapid transit, they choose a light metro.

These systems work in a very specific way. They run on a path that is completely separate from cars or buses. This is called being grade separated. Because they have their own space, they are very safe and fast. Most light metros use shorter trains with only 2 to 4 cars. They also use smaller stations than big metro systems. This helps cities save money when they build them. Some systems even use rubber tyres instead of metal wheels. This helps the trains climb steep hills and make tight turns.

Many light metros use automatic train operation. This means a computer moves the train without a human driver.

This technology allows trains to run very often. During busy times, a train might arrive every 90 seconds. This high frequency helps the system carry many passengers. Even with smaller trains, they can sometimes rival big metro systems. This is because they move so many people in a short time. A report from the World Bank says they carry 15,000 to 30,000 people per hour.

Different parts of the world use these systems in unique ways. The Vancouver SkyTrain in Canada opened in 1985. In Armenia, the Yerevan Metro began using these trains in 1981. The Copenhagen Metro in Denmark has been running since 2002. Some systems, like the Taipei Metro, use the VAL system. The VAL system is a type of light metro that uses rubber tyres. In Hong Kong, the Ma On Shan line used 4-car trains. It later grew to use 8-car trains in June 2021.

Light metros connect to the parts of travel you already know. They often act as a bridge to bigger transport networks. For example, they can link a city to a large airport. They can also connect to a main metro line. Some systems are built underground, but others stay above the ground. A system like the Ottawa O-Train uses 2-car trains that are 100 metres long. This shows how many different ways these trains can look and work. They help cities grow by moving people efficiently every single day.

A light metro is a specialized rail transport system designed for medium-capacity needs.

It occupies a unique space in urban planning between light rail and rapid transit. While it shares infrastructure similarities with rapid transit, it differs in scale. Light metro systems typically utilize shorter trains, often consisting of only two to four cars. They also feature smaller stations to help reduce construction costs. Planners use statistical modeling to determine the correct size for a rail network. If the predicted ridership falls between the requirements for light rail and heavy rapid transit, a light metro is the ideal solution.

The mechanism of a light metro relies on total separation from other traffic. This is known as an entirely grade-separated exclusive right of way. Because the tracks are completely isolated, the trains can operate safely and efficiently. Some systems utilize rubber-tyred technology, such as the VAL system used in Taipei.

Rubber tyres allow the vehicles to climb steeper grades and navigate tighter curves. This provides more flexibility for the alignment of the tracks through a city. Many of these systems also employ automatic train operation. This means computers control the movement of the trains without a human driver. This automation allows for extremely high-frequency service. During peak hours, headways—the time between trains—can be as short as 90 seconds.

Capacity is a defining metric for these systems. According to a report from the World Bank, a light metro carries between 15,000 and 30,000 passengers per hour per direction (p/h/d). In comparison, light rail systems generally carry between 10,000 and 18,000 p/h/d. Rapid transit systems are defined by carrying more than 30,000 p/h/d. However, these boundaries can vary by region. The Taiwan Ministry of Transportation and Communications defines medium-capacity systems as carrying 6,000 to 20,000 p/h/d. Meanwhile, the Taiwan Department of Rapid Transit Systems uses a higher range of 20,000 to 30,000 p/h/d. In Hong Kong, the Ma On Shan line was once classified as a medium-capacity system because it used shorter 4-car trains.

It eventually reached capacities of 32,000 p/h/d, which rivals rapid transit.

History and development show how these systems evolve. The Yerevan Metro in Armenia began operations in 1981 using 2 and 3-car trains. The Vancouver SkyTrain in Canada opened in 1985 and uses 4- to 6-car trains on its Expo line. The Copenhagen Metro in Denmark has operated since 2002 using a driverless system. In Hong Kong, the Ma On Shan line transitioned to full-length 8-car trains in June 2021 to accommodate growth. Some systems, like the South Island line in Hong Kong, opened in December 2016. These historical examples show how cities adapt their rail technology to meet changing demographics and ridership needs.

There are distinct advantages and disadvantages to choosing a light metro. The primary advantage is cost reduction. Smaller trains and shorter stations require less investment than heavy rapid transit. Additionally, light metros can be faster due to lighter trains. These vehicles often feature faster acceleration and braking. They also benefit from shorter dwell times, which is the time a train spends stopped at a station. However, they face restricted growth capacities. It is difficult to extend station platforms once a system is running, especially underground. To prepare for this, some cities make advance provisions. The Taipei Metro, for example, built extra space for two additional cars in all its Wenhu Line stations.

Notable examples exist across many different environments. The Ottawa O-Train in Canada uses 2-car trains that are 100 metres long. The Sofia Metro Line 3 in Bulgaria began using a driverless system in 2020. In Macau, the Light Rapid Transit uses Mitsubishi Crystal Mover vehicles. These vehicles run on rubber tyres on concrete tracks and are fully automated. The Disneyland Resort line in Hong Kong has operated since 2005 using driverless 4-compartment trains. These diverse examples demonstrate the many ways light metro technology can be applied to different urban landscapes.

Light metros often serve as vital connections to broader transport networks. They are frequently used for branch line connections to heavy-capacity systems. This might include linking a main metro network to an airport. They can also act as a bridge between different modes of transport. Because they can be built above ground or underground, they fit into various urban structures.

Whether they are part of a massive metropolitan web or a specialized shuttle, they provide a scalable solution for moving people through a modern world.