Burning fossil fuels for electricity generation produces large quantities of gaseous emissions:

• Carbon dioxide (CO₂) is the main greenhouse gas. At its current level of concentration in the atmosphere, CO₂ has been essential for maintaining the present temperature on Earth, making it habitable.

• Sulphur dioxide (SO₂) is a cause of acid rain. However, it also forms sulphate aerosols in the atmosphere which helps reduce some of the greenhouse effect from carbon dioxide.

• Nitrogen oxides (NO_X) and particulates are health hazards and irritants. Nitrous oxide is also a greenhouse gas.

Emissions that come directly from burning fuels for electricity generation are called direct emissions. They have been increasing in line with economic development and are expected to continue to increase in the future.

Source: IEA Net Zero by 2050 Scenario (May 2021)

Emissions of Energy Sources

According to the Climate Change 2021: The Physical Science Basis report of the Intergovernmental Panel on Climate Change (IPCC) concludes that the emissions of greenhouse gases from human activities are responsible for approximately 1.1°C of warming since 1850-1900, and it is estimated that global temperature may reach or exceed 1.5°C of warming over the next 20 years. Energy-related greenhouse gas emissions account for the majority of all anthropogenic emissions which are responsible for over 40% of all energy-related emissions. The impacts of electricity generation go beyond the emission of CO₂ and other greenhouse gases. Therefore, stabilising the climate will require cleaner electricity generation, and sustained reductions in greenhouse gas emissions. On a life-cycle basis, nuclear and renewable energy emit far less CO₂ than conventional fossil fuel are the most readily decarbonised. 

Environmental Impact and Monitoring

A nuclear power station discharges a small amount of radioactivity during its normal operation. However, the amount is regulated by the state licensing authority and is carefully monitored to ensure a very low, if not insignificant, environmental impact. See more in Performance Monitoring.