Electricity's Pollution Footprint: What's The Impact?

Electricity generation has a significant impact on the environment, and almost all methods of electricity generation produce some form of waste. The burning of fossil fuels, such as coal, gas, oil, and biomass, releases harmful pollutants into the atmosphere, affecting air, water, and land, and posing risks to human health. Nuclear power plants produce radioactive waste, which can remain dangerous for thousands of years, while renewable energy sources such as wind, solar, and geothermal power have less environmental impact but still present some challenges. The generation and delivery of electricity can also harm local wildlife, and power plant accidents have caused long-lasting damage to animal populations. While there are laws and regulations in place to control emissions and minimise environmental impacts, the complex system of electricity generation, delivery, and end-users continues to present challenges for sustainability.

Electricity generation and air pollution

Electricity generation is a major source of air pollution, which has been linked to premature deaths and health issues, particularly in certain racial and ethnic groups. The burning of fossil fuels, such as coal, gas, oil, and biomass, releases harmful pollutants into the atmosphere, including sulfur dioxide, nitrogen dioxide, carbon monoxide, and mercury. These emissions contribute to particle pollution, with ash and soot forming directly and indirectly through the conversion of sulfur and nitrogen dioxide emissions.

In the United States, the electric power sector is responsible for about 31% of energy-related CO2 emissions, with power plants burning fossil fuels or materials derived from them being a significant contributor. The transportation and storage of fuels can also create additional emissions, impacting the health of workers and communities near extraction sites and along transportation routes.

To address air pollution from electricity generation, the United States has implemented laws such as the Clean Air Act, which regulates air pollutant emissions from power plants. Emission standards limit the amount of certain substances power plants can release, and various technologies are employed to meet these standards, including burning low-sulfur-content coal, co-firing wood chips with coal, and using particulate emission control devices.

The transition to renewable and distributed energy sources, such as wind, solar, geothermal, and tidal power, is crucial for reducing air pollution and its associated health impacts. These "zero-emission" sources can significantly decrease health risks and premature deaths, providing cleaner and more reliable power to customers.

While electricity generation methods vary, with some sources being natural gas, coal, and nuclear power, the adoption of energy-efficient technologies and practices can also help reduce the environmental impacts of electricity generation and the need for electricity generation overall.

Fossil fuels and climate change

Electricity generation is a major source of pollution. Power plants that burn fossil fuels to generate electricity produce air pollutants that are harmful to human health and the environment. These pollutants include particulate matter (PM), heavy metals such as mercury, and hazardous air pollutants (HAPs). The combustion of fossil fuels also releases carbon dioxide (CO2), a greenhouse gas that contributes to climate change. In 2022, power plants burning fossil fuels were responsible for about 31% of total US energy-related CO2 emissions.

Fossil fuels, such as coal, oil, and natural gas, are formed from the decomposition of carbon-based organisms that died millions of years ago. These fuels are non-renewable and currently supply around 80% of the world's energy. When burned, they release large amounts of carbon dioxide into the atmosphere. Carbon dioxide and other greenhouse gases, such as methane, trap heat in the Earth's atmosphere, leading to global warming and climate change.

The effects of climate change are already being felt worldwide. The average global temperature has increased by 1°C, and global temperatures passed the critical 1.5°C milestone in 2024. Warming above this level poses significant risks, including sea-level rise, extreme weather events, biodiversity loss, species extinction, food scarcity, and worsening health and poverty for millions of people. Climate change is also impacting water availability, making it scarcer in many regions and increasing the risk of agricultural and ecological droughts.

To address these issues, there have been efforts to transition to cleaner energy sources and reduce fossil fuel emissions. The Paris Agreement of 2015 committed governments to reducing carbon emissions. However, fossil fuel companies remain major polluters, and a recent report indicates that global fossil fuel production is on track to exceed the limits necessary to keep warming below 1.5°C. As a result, scientists and organizations emphasize the urgent need for a mass switch to renewable energy sources, such as solar, wind, and geothermal power, which produce little to no greenhouse gas emissions or pollution.

Nuclear power and radioactive waste

Nuclear power plants do not produce greenhouse gases, PM, SO2, or NOx, but they do produce radioactive waste. Radioactive waste is a major environmental concern related to nuclear power. There are three types of nuclear waste, classified according to their radioactivity: low-, intermediate-and high-level. Low-level waste includes contaminated protective shoe covers, clothing, wiping rags, mops, filters, reactor water treatment residues, equipment, and tools. It is stored at nuclear power plants until the radioactivity in the waste decays to a level safe for disposal as ordinary trash, or it is sent to a low-level radioactive waste disposal site.

High-level waste, which includes highly radioactive spent nuclear fuel assemblies, must be stored in specially designed storage containers and facilities. The radioactivity of nuclear waste decreases over time through a process called radioactive decay. The amount of time it takes for the radioactivity of radioactive material to decrease to half its original level is called the radioactive half-life. Radioactive waste with a short half-life is often stored temporarily before disposal to reduce potential radiation doses to workers who handle and transport the waste. This storage system also reduces radiation levels at disposal sites.

By volume, most of the waste related to the nuclear power industry has a relatively low level of radioactivity. Uranium mill tailings contain the radioactive element radium, which decays to produce the radioactive gas radon. Most uranium mill tailings are placed near the processing facility and are covered with a sealing barrier of clay to prevent radon from escaping into the atmosphere. The sealing barrier is then covered by a layer of soil, rocks, or other materials to prevent erosion.

Nuclear waste has never caused harm to people, and the idea that it remains a threat for billions of years is a misconception. While nuclear waste remains weakly radioactive for a few hundred thousand years, the radioactivity will have decayed to safe levels within a few hundred years. The quantity of materials that would be found in the environment in the event of a leak would be very small and would make no difference to the natural environment or future humans. The environment and the human body are naturally radioactive, and the doses from a nuclear waste repository would be almost 50 times smaller than the average background radiation.

Some countries have used plutonium recycling to generate electricity while also reducing the radiological footprint of their waste. However, some by-products will still require disposal in a repository and are immobilized by mixing them with glass through a process called vitrification. Direct disposal is a strategy where used nuclear fuel is designated as waste and disposed of in an underground repository without any recycling. The waste is placed in canisters that are sealed with rocks and clay.

Renewable energy and clean power

The generation and transmission of electricity can have a significant impact on the environment, and the extent of this impact depends on how and where the electricity is generated and delivered. Power plants that burn fossil fuels, such as coal, gas, oil, and biomass, release harmful pollutants into the atmosphere, affecting both the environment and human health. These emissions include sulfur dioxide, nitrogen dioxide, carbon monoxide, mercury, and hazardous pollutants that can cause cancer and other health issues.

To address these environmental concerns, the transition to renewable and clean energy sources is crucial. Renewable energy sources, such as solar, wind, hydropower, biofuels, geothermal, and tidal power, are at the forefront of this transition. These sources offer a more sustainable and carbon-intensive approach to energy generation. Hydropower, or hydroelectric power, is one of the oldest and largest sources of renewable energy, generating electricity through the natural flow of moving water.

The expansion of the renewable energy sector is well underway, with global renewable electricity generation expected to reach over 17,000 terawatt-hours by the end of the decade. This growth is driven by increased policy support and cost reductions, particularly for solar photovoltaics and wind power. The European Union, for example, has proposed increasing its renewable energy target for 2030 to 45% through initiatives like the REPowerEU Plan and The Green Deal Industrial Plan.

In the United States, the clean energy industry is experiencing significant growth, generating hundreds of billions in economic activity. The country is investing in renewable energy technologies and aiming to advance technologies that drive down the cost of solar energy. Additionally, states along the east coast have set offshore wind targets, with the Biden administration supporting the development of 30 GW of offshore wind energy by 2030.

To further accelerate the adoption of clean energy, various incentives and policies are being implemented. Production tax credits, loans, and grants can incentivize research, innovation, and procurement in the clean energy sector. Bonus tax incentives for developers investing in low-income communities and areas affected by dirty power plants are also crucial for a just transition. Additionally, energy efficiency plays a vital role in reducing electricity demand and can be achieved through the adoption of energy-efficient technologies and practices.

The impact on human health

The generation of electricity has a significant impact on human health. The burning of fossil fuels for electricity production results in the emission of harmful pollutants, including carbon dioxide, nitrogen oxide, and sulfur dioxide, contributing to global warming and climate change. These emissions degrade air quality and pose risks to lung health, with those living near power plants being particularly vulnerable. Additionally, the mining, extraction, and transportation of fuels can directly harm workers and nearby communities. Diesel locomotives used to transport coal contribute further to pollution emissions.

Power plants using coal, oil, and gas are the largest sources of carbon pollution and are responsible for releasing hazardous particulate matter, such as ash and soot. Ash sludge, a mixture of ash and water, is often stored in unlined retention ponds, posing risks to groundwater. Coal-fired power plants also produce fly ash, which contains hazardous materials captured by pollution control devices. While nuclear power plants do not produce greenhouse gases or particulate matter, they generate radioactive waste that must be carefully stored and can remain radioactive for thousands of years. This waste can cause cancer and genetic mutations in humans and animals.

The use of renewable energy sources, such as wind, solar, geothermal, and tidal power, is critical for improving lung health and reducing premature deaths associated with air pollution. These "zero-emission" sources of electricity do not burn fuel and thus emit no air pollution, helping to limit climate change. However, wind farms can have a significant visual impact on the landscape and may affect people living in close proximity to the turbines.

The electric power sector is a significant contributor to carbon dioxide emissions, with power plants burning fossil fuels or materials derived from them being the source of about 31% of total U.S. energy-related CO2 emissions in 2022. These emissions enhance the greenhouse effect, leading to global warming and its associated health impacts. Climate change threatens public health and affects ecosystems, influencing plant growth, animal behaviour, and the interactions between organisms and their physical environment.

To mitigate the health impacts of electricity generation, the United States has implemented laws such as the Clean Air Act, which regulates air pollutant emissions from power plants. Additionally, power plants employ various methods to meet air pollution emission standards, including burning low-sulfur-content coal, co-firing wood chips with coal, and using particulate emission control devices like bag-houses and electrostatic precipitators. These efforts aim to reduce the presence of harmful pollutants in the air and minimize their impact on human health.

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