Electricity generation

There are exotic and speculative methods to recover energy, such as proposed fusion reactor designs which aim to directly extract energy from intense magnetic fields generated by fast-moving charged particles generated by the fusion reaction (see magnetohydrodynamics).

[5] However, in 2023, it was reported that the global electricity supply was approaching peak CO2 emissions thanks to the growth of solar and wind power.

[6] The fundamental principles of electricity generation were discovered in the 1820s and early 1830s by British scientist Michael Faraday.

His method, still used today, is for electricity to be generated by the movement of a loop of wire, or Faraday disc, between the poles of a magnet.

The new technology was quickly adopted by many cities around the world, which adapted their gas-fueled street lights to electric power.

This conversion of heat energy into mechanical work was similar to that of steam engines, however at a significantly larger scale and far more productively.

Throughout the middle of the 20th century many utilities began merging their distribution networks due to economic and efficiency benefits.

[12] Until recently, photovoltaics were most commonly used in remote sites where there is no access to a commercial power grid, or as a supplemental electricity source for individual homes and businesses.

Recent advances in manufacturing efficiency and photovoltaic technology, combined with subsidies driven by environmental concerns, have dramatically accelerated the deployment of solar panels.

Installed capacity is growing by around 20% per year[2] led by increases in Germany, Japan, United States, China, and India.

The selection of electricity production modes and their economic viability varies in accordance with demand and region.

The daily minimum[citation needed] is the base load, often supplied by plants which run continuously.

In general, some form of prime mover such as an engine or the turbines described above, drives a rotating magnetic field past stationary coils of wire thereby turning mechanical energy into electricity.

[14] The only commercial scale forms of electricity production that do not employ a generator are photovoltaic solar and fuel cells.

Almost all commercial electrical power on Earth is generated with a turbine, driven by wind, water, steam or burning gas.

There are many different methods of developing mechanical energy, including heat engines, hydro, wind and tidal power.

The combustion of fossil fuels supplies most of the energy to these engines, with a significant fraction from nuclear fission and some from renewable sources.

The modern steam turbine, invented by Sir Charles Parsons in 1884, currently generates about 80% of the electric power in the world using a variety of heat sources.

Supercritical carbon dioxide blends, that are currently in development, can further increase efficiency by optimizing its critical pressure and temperature points.

Total world generation in 2021 was 28,003 TWh, including coal (36%), gas (23%), hydro (15%), nuclear (10%), wind (6.6%), solar (3.7%), oil and other fossil fuels (3.1%), biomass (2.4%) and geothermal and other renewables (0.33%).

[19] In the United States, fossil fuel combustion for electric power generation is responsible for 65% of all emissions of sulfur dioxide, the main component of acid rain.

[20] Electricity generation is the fourth highest combined source of NOx, carbon monoxide, and particulate matter in the US.

[26] Nuclear power plants can also create district heating and desalination projects, limiting carbon emissions and the need for expanded electrical output.

Processes such as coal and gas not only release carbon dioxide as they combust, but their extraction from the ground also impacts the environment.

These facilities are usually located far away from consumers and distribute the electricity through high voltage transmission lines to a substation, where it is then distributed to consumers; the basic concept being that multi-megawatt or gigawatt scale large stations create electricity for a large number of people.

Many of the largest operational onshore wind farms are located in China, India, and the United States.

[41][a] They generate about a third of the world's electricity,[42] but cause many illnesses and the most early deaths per unit of energy produced,[43] mainly from air pollution.

The furnace heat converts boiler water to steam, which is then used to spin turbines that turn generators.

[60] Normal emissions due to nuclear power plants are primarily waste heat and radioactive spent fuel.

In a reactor accident, significant amounts of radioisotopes can be released to the environment, posing a long term hazard to life.