Air Pollution: Energy's Dark Side?

Air pollution is one of the most significant environmental risks to human health, with one in nine deaths linked to poor air quality. The World Health Organization (WHO) estimates that 92% of the world's population lives in areas where air pollution exceeds recommended limits. The primary sources of air pollution include the energy sector, with oil being the most significant contributor to energy consumption and air pollution, followed by the transport sector, which was responsible for 28% of total energy consumption in 2016. Other sources of air pollution include natural gas, nuclear power, and coal-based electricity generation. The effects of air pollution are detrimental to human health and the planet, causing respiratory and cardiac issues, and contributing to climate change. Transitioning to cleaner fuels and improving energy efficiency are crucial steps in mitigating air pollution and its associated health and environmental risks.

Oil and gas extraction and refinement

One of the main sources of air pollution from oil refineries is the refining of crude oil, which includes processes such as distillation, hydrotreating, and reforming. These processes release volatile organic compounds, including hydrocarbons, greenhouse gases (such as carbon dioxide and methane), nitrogen oxides, and sulphur dioxide. These gases contribute to climate change and the degradation of ecosystems, affecting both nearby communities and distant ecosystems. Oil extraction also generates greenhouse gas emissions, with refineries being the third-largest global emitter of greenhouse gases.

Natural gas extraction also contributes to air pollution. Natural gas wells often produce semi-liquid condensates, which are composed of hydrocarbons, including aromatic hydrocarbons like benzene, toluene, xylenes, and ethylbenzene (BTEX). These compounds have characteristic odours and can be detected by smell at certain levels. The combustion of natural gas can release pollutants such as carbon dioxide, carbon monoxide, sulfur dioxide, nitrogen oxides, and other compounds. Additionally, engines used in natural gas wells and pipelines produce additional air pollutants and noise.

The development and extraction processes of oil and gas release a variety of air contaminants from multiple sources. For example, drilling wastes, fracking wastes, and produced water are often stored in open earthen or metal pits, leading to the potential escape of chemicals and compounds into the atmosphere. Fugitive emissions, or unintentional leaks, can occur from breaks or small cracks in seals, tubing, valves, or pipelines, releasing natural gas, methane, volatile organic compounds (VOCs), and other contaminants.

To mitigate the air pollution caused by oil and gas extraction and refinement, a transition to cleaner fuels and industrial processes is necessary. This includes adopting renewable energy sources, improving fuel efficiency, and electrifying transportation. Regulatory precautions and monitoring solutions are also crucial to minimizing the environmental impact of the oil and gas industry.

Nuclear power

Nuclear reactors emit virtually no air pollutants, and their use has prevented about 1.8-2 million air pollution-related deaths over the years. A 2019 study by the International Energy Agency found that over 60 gigatons of net greenhouse gas emissions were avoided globally in the last 50 years due to nuclear power. This has had a significant impact on reducing air pollution and its associated health risks, such as respiratory health conditions.

However, nuclear power does produce radioactive waste that can be harmful to the environment if not properly managed. This waste includes spent nuclear fuel, which contains carcinogenic radionuclide isotopes, and contaminated tools, protective clothing, and other disposable items from nuclear fuel processing facilities. These materials are subject to strict regulations for their handling, storage, and disposal to prevent them from contaminating the outside environment.

Despite the potential risks associated with nuclear power, studies have shown that shutting down nuclear power plants could lead to an increase in air pollution. This is because the energy gap left by nuclear power would likely be filled by coal, gas, and oil sources, which are more polluting and harmful to human health. According to an MIT study, retiring nuclear power plants could result in an additional 5,200 pollution-related deaths over a single year.

Overall, nuclear power plays a crucial role in reducing air pollution and GHG emissions while meeting global energy needs. It is an essential part of the clean energy transition, providing secure and flexible electricity supply. However, the safe handling and disposal of nuclear waste are critical to minimizing the environmental impact of nuclear power.

Renewable energy sources

Air pollution is the fourth-largest risk factor for premature death globally, with 4.5 million deaths linked to outdoor air pollution in 2019 and a further 2.2 million caused by indoor air pollution. The transition to renewable energy sources is the most effective way to reduce air pollution. Renewable energy sources are naturally replenishing, virtually inexhaustible, and typically have a low- or zero-carbon footprint.

Wind Power

Wind power is the largest producer of renewable electricity in the UK and the US. Wind farms generate electricity by spinning the blades of wind turbines, which convert the kinetic energy of the spinning blades into electric energy. Wind power accounted for 9.2% of US electricity generation and is one of the cheapest energy sources in the country.

Solar Power

Solar power generates electricity by capturing sunlight on solar panels through a joint chemical and physical reaction known as the photovoltaic effect. Despite being one of the planet's most freely available energy resources, solar power is dependent on the amount of sunlight, which varies depending on location, season, and time of day.

Hydropower

Hydropower relies on water flowing through a dam to spin turbines and create electricity. It is considered a clean and renewable source of energy because it does not directly produce pollutants, and the source of power is regenerated. Hydropower is the largest renewable energy source for electricity in the US, though wind energy is expected to take over soon.

Bioenergy

Bioenergy is generated when organic matter, such as plants, timber, or food waste, is burned as fuel. Carbon dioxide is emitted when bioenergy is produced, but these fuel sources are considered renewable because they can be regrown, and they absorb as much carbon as they emit over their lifespans.

Transport emissions

Transport is a major contributor to air pollution, with the sector accounting for around one-fifth of global carbon dioxide (CO2) emissions. Road travel accounts for the majority of these emissions, with passenger vehicles such as cars and buses contributing the most. The reliance of transport on oil and combustion engines that run on fossil fuels is a significant factor in this.

In recognition of the impact of transport emissions, various jurisdictions have implemented policies to encourage the adoption of electric vehicles (EVs) and the development of alternative fuels. For example, the United States has made strides with the Inflation Reduction Act, which includes measures to accelerate EV adoption and the production of biofuels, synthetic fuels, and hydrogen. The US Environmental Protection Agency (EPA) has also proposed multi-pollutant emissions standards for light and heavy-duty vehicles. The European Union has similarly pushed for the transition to EVs through the Green Deal Industrial Plan and the Alternative Fuels Infrastructure Regulation, which will mandate member states to roll out public charging for electric vehicles.

In addition to policy efforts, technological innovations offer a promising solution to reduce transport emissions. The rise of electric vehicles and the development of low-emissions fuels, such as hydrogen technologies, are crucial in this regard. According to the International Energy Agency (IEA), some transport sub-sectors could achieve decarbonization within decades through electrification and hydrogen technologies. However, it is important to note that certain transport sectors, such as aviation, will be more challenging to decarbonize.

While progress is being made, stronger efforts are needed to align with the IEA's Net Zero Scenario, which requires transport sector emissions to fall by around a quarter by 2030. This involves not only the rapid electrification of road vehicles but also the implementation of energy efficiency measures and policies that promote less carbon-intensive travel options, such as walking, cycling, and public transportation.

Health impacts

Air pollution is the presence of one or more contaminants in the atmosphere, such as dust, fumes, gas, mist, odour, smoke, or vapour, in quantities and durations that can be harmful to human health. It is the fourth-largest risk factor for premature death worldwide, with 4.5 million deaths linked to outdoor air pollution exposure and another 2.2 million caused by indoor air pollution in 2019. Fine particulate matter (PM2.5) is the air pollutant driving the most significant health problems, including premature mortality. In 2021, 97% of the urban population was exposed to concentrations of fine particulate matter above the health-based guideline level set by the World Health Organization.

The main pathway of exposure from air pollution is through the respiratory tract. Breathing in these pollutants leads to inflammation, oxidative stress, immunosuppression, and mutagenicity in cells throughout the body, impacting the lungs, heart, and brain, among other organs, and ultimately leading to disease. Almost every organ in the body can be impacted by air pollution, as some pollutants are small enough to penetrate the bloodstream via the lungs and circulate throughout the entire body, leading to systemic inflammation and carcinogenicity. The health impacts of air pollution include a wide range of diseases, such as stroke, chronic obstructive pulmonary disease, trachea, bronchus and lung cancers, aggravated asthma, and lower respiratory infections. The World Health Organization (WHO) also provides evidence of links between exposure to air pollution and type 2 diabetes, obesity, systemic inflammation, Alzheimer's disease, and dementia.

Maternal exposure to air pollution is associated with adverse birth outcomes, such as low birth weight, pre-term birth, and small gestational age births. Additionally, a growing body of evidence suggests that air pollution may affect diabetes and neurological development in children. Older people, children, and those with pre-existing health conditions are more sensitive to the health impacts of air pollution. Lower socio-economic status is also linked to increased exposure to air pollution, as people with lower incomes often live closer to busy roads or industrial areas.

The best way to control air pollution and mitigate its health impacts is to transition to cleaner fuels and industrial processes. This includes adopting renewable energy sources such as wind and solar power, improving fuel efficiency in vehicles, and transitioning to electric cars and trucks. These measures will not only limit air pollution at its source but also help curb the global warming that intensifies its worst health impacts.

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