Trains' Impact: Air Pollution And Possible Solutions

Trains are widely considered to be one of the greenest modes of transportation. However, they still contribute to air pollution, especially when powered by diesel engines. Electric trains, on the other hand, are emission-free. Diesel trains emit large quantities of pollutants, threatening the health and well-being of travellers and workers. Locomotive exhaust contains harmful substances such as particulate matter (PM) and nitrogen oxides, which are linked to serious health issues, including heart, lung, and cardiovascular disease and asthma. In the United States, freight trains are a significant source of pollution, impacting communities of colour and low-income populations disproportionately. While the transport sector accounts for about 22% of global emissions, rail travel only contributes a small fraction of that amount. Nevertheless, efforts are being made to transition to cleaner locomotives and reduce rail idling to improve air quality and protect public health.

Diesel trains emit large quantities of pollutants, causing poor air quality

While trains are considered a low-carbon mode of transportation, diesel trains emit large quantities of pollutants, causing poor air quality and threatening the well-being of frequent travellers and workers. According to a study, the potential for diesel trains to emit pollutants is particularly high in enclosed stations. Globally, rail travel is considered one of the greenest modes of transportation, with rail accounting for only 0.8% of global emissions between 1990 and 2009. However, diesel trains contribute significantly to air pollution, especially in areas with non-electrified train lines.

Diesel engines used in trains release various pollutants, including particulate matter, nitrogen oxides, hydrocarbons, and carbon monoxide. These emissions have severe health impacts on individuals living or working near railway infrastructure. Locomotive exhaust containing particulate matter can burrow deep into the lungs, causing poisoning. Nitrogen oxides emitted by diesel trains create smog, which is directly linked to heart, lung, and cardiovascular disease and asthma. The impact of diesel train emissions is particularly pronounced in low-income communities and communities of colour, who are disproportionately affected by transportation pollution.

In the UK, only 41% of train tracks are electrified, leaving a significant number of diesel-powered trains in operation. Public Health England estimates that 29,000 deaths per year in the UK are caused by air pollution, highlighting the urgency of improving air quality. While there have been efforts to replace or retrofit older diesel locomotives with more efficient engines, it is technically and economically challenging. The most feasible approach to reducing emissions is through fleet renewal, as older locomotives are remanufactured to extend their lifespan instead of being replaced with zero-emission alternatives.

To address the issue of diesel train emissions, several measures can be implemented. Firstly, there should be a focus on electrifying more train tracks to reduce the reliance on diesel locomotives. Additionally, rail companies should be incentivized to replace old, polluting locomotives with clean, zero-emission alternatives. Governments can play a crucial role by enforcing environmental standards for diesel engines and setting emission reduction goals, as outlined in initiatives like the Low Carbon Sustainable Rail Transport Challenge. Furthermore, improving air quality inside train stations is essential, as poor station air quality can pose a significant risk to travellers and workers, especially in enclosed stations.

Electric trains are emission-free, but many countries still rely on diesel locomotives

Diesel trains contribute to air pollution by releasing gases and particles into the atmosphere during the combustion of diesel fuel. This includes pollutants such as particulate matter (PM), nitrogen oxides, hydrocarbons (HC), and carbon monoxide (CO). These emissions have severe health impacts, especially for communities living near freight railroad infrastructure. Locomotive exhaust containing nitrogen oxides, for instance, creates smog, which is directly linked to heart, lung, and cardiovascular disease and asthma.

The use of diesel trains is particularly prevalent in Europe, with about 20% of rail traffic hauled by diesel locomotives. Countries like the UK, Greece, Estonia, Latvia, and Lithuania are highly dependent on diesel traction. In the UK, only 41% of train tracks are electrified, and poor air quality within train stations has been a concern. While efforts have been made to improve air quality, such as the EU's Stage IIIA and IIIB standards for diesel engine emissions, the challenge of reducing emissions from older diesel locomotives remains.

The solution lies in transitioning to electric trains, which are emission-free at the point of use. Electrifying train tracks and replacing or retrofitting older diesel locomotives with electric engines can significantly reduce pollution. California, for example, has passed rules to fund cleaner, zero-emission locomotives, setting an example for other states and countries to follow. By accelerating the adoption of electric trains and improving the utilization of railway networks, countries can effectively reduce air pollution and mitigate the health risks associated with diesel locomotive emissions.

While electric trains offer a cleaner alternative, it is important to acknowledge that the transport sector as a whole contributes significantly to global emissions. Trains, including electric trains, are still responsible for a small percentage of these emissions. However, compared to other modes of transportation, such as cars and planes, trains, especially electric trains, are a much lower-carbon option for medium-to-long-distance travel.

Rail companies remanufacture old, polluting trains, causing health issues for nearby communities

Rail companies remanufacturing old, polluting trains is causing health issues for nearby communities. While trains are considered a lower-impact mode of transport than flying, the rail industry's practice of "remanufacturing" old locomotives is contributing to air pollution and health issues for those living near rail infrastructure. This process involves repairing and extending the life of older trains, which can result in decades of continued pollution and negative health impacts for surrounding communities.

In the United States, freight trains are a significant source of pollution, particularly in communities of color and low-income areas. More than 13 million people in the U.S., predominantly people of color and lower-income individuals, are directly impacted by locomotive pollution. Locomotive exhaust contains particulate matter (PM) and nitrogen oxides, which are linked to serious health issues such as heart, lung, and cardiovascular disease, as well as asthma.

The practice of remanufacturing old trains is a key concern. By keeping these "'zombie trains" in operation, rail companies are effectively poisoning communities with huge health consequences. Environmental justice leaders and affected communities are demanding change, calling for the replacement of these old trains with clean, zero-emission locomotives.

To address this issue, California's Air Resources Board has passed a rule to fund cleaner, zero-emission locomotives, reduce rail idling near residential areas, and drive the turnover of older, polluting trains. This state-level initiative is crucial in pushing for industry-wide decarbonization and setting a precedent for national action. However, rail companies are resisting these efforts, employing aggressive legal strategies to maintain the status quo.

The remanufacturing of locomotives is a global issue, with companies in North America and Europe offering services to extend the life of older trains. While this may provide cost-effective solutions for rail operators, it comes at the expense of the health and well-being of nearby communities. It is essential to prioritize the adoption of cleaner technologies and fuels in the rail sector to mitigate the health and environmental impacts of train pollution.

Freight trains emit more carbon pollution than many US states, impacting over 13 million people

Trains are a significant contributor to air pollution, and freight trains, in particular, are a major source of carbon pollution. The impact of freight trains on air quality is especially pronounced in the United States, where these trains emit more carbon pollution than many individual states, affecting the lives of over 13 million people.

Freight trains, which transport goods rather than passengers, make up the vast majority of trains in the US. Unlike passenger trains, freight trains are typically not electrified and rely on diesel fuel, which has a high carbon footprint and contributes to climate change. The burning of diesel fuel releases carbon dioxide (CO2), a greenhouse gas, and other harmful pollutants into the atmosphere.

The emissions from freight trains are not limited to carbon dioxide. Locomotive exhaust contains particulate matter (PM) and nitrogen oxides. Particulate matter is a toxic pollutant that can penetrate deep into the lungs, causing serious health issues. Nitrogen oxides contribute to the formation of smog, which is linked to respiratory and cardiovascular diseases, including asthma.

The impact of freight train pollution is disproportionately felt by communities of colour and low-income communities. More than 13 million people from these communities live and work near railyards, rail lines, and ports, bearing the brunt of the pollution from these vehicles. The pollution from freight trains results in poor air quality, leading to dangerous health issues and reduced life expectancy for those exposed.

Recognizing the urgency of the situation, states like California have taken the initiative to address freight train pollution. California's Air Resources Board has passed rules to fund cleaner, zero-emission locomotives, reduce rail idling near residential and educational areas, and phase out old, remanufactured locomotives. These measures are expected to significantly reduce nitrogen oxide pollution and greenhouse gas emissions, saving lives and improving air quality for millions of people.

Trains are a low-carbon mode of transport, reducing emissions by 80% compared to cars

Trains are a much more environmentally friendly mode of transport than cars. Taking a train instead of a car for medium-length distances can reduce emissions by around 80%. Electric vehicles are nearly always lower-carbon than petrol or diesel cars, and the longer you keep and use an electric vehicle, the lower its carbon footprint compared to a petrol or diesel car. Trains are also more energy-efficient than cars, even when the emissions generated by both car and train infrastructure and the materials used in their production are taken into account.

However, it is important to note that the environmental impact of trains can vary depending on the energy mix used to power them. For example, in Germany, the increased use of coal-fired power generation in 2021 led to higher CO2 emissions for electric trains. Similarly, in the UK, diesel trains that run north of Edinburgh, where electric trains cannot operate, produce more carbon emissions than those powered by electricity from the national grid, which is decarbonizing by removing fossil fuel power stations.

In addition to the environmental benefits of trains over cars, it is also worth considering the social impact. Polluting freight trains and trucks often pass through or near communities of color and low-income communities, subjecting them to poor air quality and health issues. Locomotive exhaust contains pollutants such as particulate matter (PM) and nitrogen oxides, which have been linked to heart, lung, and cardiovascular disease and asthma. Therefore, transitioning to cleaner, zero-emission locomotives is crucial to improving the health and well-being of these vulnerable communities.

While walking, cycling, and long-distance buses are generally considered the most climate-friendly modes of transport, trains offer a more sustainable alternative to cars, especially for medium-to-long-distance travel. By choosing trains over cars, individuals can play a significant role in reducing their carbon footprint and contributing to the fight against climate change.

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