Coal-fired power station

A coal-fired power station is a special kind of power plant that uses coal to make electricity. It works by burning coal in a very hot furnace. This heat turns water into steam, and the steam spins big machines called turbines. These turbines then power generators, which create electricity for our homes and cities.

There are many of these plants around the world. They help give us the electricity we need, but they can also cause problems for our health and the environment. The air pollution they create can make people sick. They also release large amounts of carbon dioxide into the air, which helps warm our planet.

Even though some countries are trying to use cleaner ways to make electricity, many new coal plants are still being built. This makes it important to think about better, safer ways to power our world.

History

See also: Power station § History

The first coal-fired power stations were built in the late 1800s. They used special engines to make electricity. Later, bigger plants used steam turbines to bring electricity to more places.

Transport and delivery of coal

Coal can reach power stations in many ways. It may come by trucks on roads, by rail, on boats, by collier ships, or through special pipelines. Sometimes, power stations are built near coal mines, especially for lignite. In these cases, coal may arrive by conveyor belt or in large diesel-electric-driven trucks.

Very long trains, called “unit trains,” can be over 2 kilometers long and carry a lot of coal in one trip. Big power plants may need one of these big trains each day, and sometimes they get even more trains a day, especially when it is very hot or very cold.

Operation

See also: Thermal power station

A coal-fired power station makes electricity from coal. First, coal is broken into small pieces and burned. The heat turns water into steam. The steam makes big machines called turbines spin, and these turbines help make electricity.

Coal power stations have to deal with ash left over from burning coal. This ash is kept in special ponds or landfills so it does not hurt the environment. Some of this ash can be used again in building materials.

Coal power generation

Most of the coal we burn is used to make electricity. In 2020, coal was the biggest source of electricity around the world, giving us about 34% of all the power we use. China, India, and Indonesia got most of their electricity from coal.

In 2020, the world had about 2,059 GW of coal power stations. By 2023, this grew to 2,130 GW, mostly because China added more. Some countries promised to stop using coal in 2021, but many places, like Indonesia and Vietnam, still find it hard to change away from coal.

Efficiency

Coal-fired power stations come in four main types. They are listed from least efficient to most efficient: subcritical, supercritical, ultra-supercritical, and cogeneration (also called combined heat and power or CHP). Subcritical plants are the least efficient, but new improvements have made older subcritical plants more efficient.

Integrated gasification combined cycle design

Main article: Integrated gasification combined cycle

Integrated gasification combined cycle (IGCC) is a way to make electricity from coal. It uses a special machine called a gasifier to change coal into a gas. This gas can then be used in a combined cycle generator, which usually makes electricity more efficiently. IGCC can also help clean the gas before it makes electricity. But this method costs more money than regular coal power plants.

Carbon dioxide emissions

See also: Fossil fuel power station § Carbon dioxide

Coal-fired power stations release a lot of a gas called carbon dioxide, which is bad for the environment. They make more of this gas than most other ways we create electricity.

Mitigation

Phase out

See also: Coal phase out

Some older coal power stations are being shut down, but new ones are still being built in some places. Leaders have said that we need to stop using coal to make electricity by certain years to help protect our planet.

Ammonia co-firing

See also: Ammonia

Scientists are testing a new way to use a substance called ammonia to help cut down on carbon dioxide from coal power stations. This is being tried in Japan.

Conversion

Some power stations are changing so they can burn things like gas, plant material, or waste instead of coal.

Carbon capture

See also: Carbon capture and storage

Some people think we could add special equipment to coal power stations to catch the carbon dioxide, but this is very expensive and might not work for all stations.

Pollution

Main article: Environmental impact of the coal industry

Coal-fired power plants create smoke that can make people sick. This smoke has tiny particles that can get into our lungs and bodies. Some places have rules to try to reduce this pollution. Burning coal can also pollute water with dangerous metals, which can harm animals and fish.

Economics

Coal power plants are used for steady electricity because they can run almost all the time. But this makes them less flexible when market conditions change.

In 2020, the coal industry got $18 billion in subsidies.

Financing coal projects can clash with international climate goals, such as those in the Paris Agreement. The Paris Agreement wants to limit global warming. Supporting coal makes it harder to reach these goals.

Some countries have helped coal projects in other countries. This can create long-term risks. As renewable energy gets cheaper, the benefits of coal projects shrink. There is a push for better policies to limit funding for coal projects.

Politics

In May 2021, the G7 agreed to stop supporting coal-fired power stations. This is important because using coal for energy has gone down. However, countries like China and India still use a lot of coal.

As of 2023, the Group of Twenty (G20) controls most of the world's coal power stations. Decisions made by China about coal will affect the future of these power stations, as the country has many of them.

People have also protested against coal mining and new power plants in places like Hambach Forest, Akbelen Forest, and Ffos-y-fran.