Using a nuclear fission reaction and uranium as fuel, nuclear power plants generate a high amount of electricity. As nuclear power plants are considered to be a low-carbon energy source, the technology is widely thought of as a more environmentally-friendly option. When compared to renewable sources of energy such as solar and wind, the power generation from nuclear power plants is also considered to be more reliable. Although the investment required to bring a nuclear power plant online is significant, the costs involved in operating them are relatively low.
Hydroelectricity is produced by harnessing the gravitational force of flowing water. Compared to fossil fuel-powered energy plants, hydroelectric power plants emit fewer greenhouse gases. But the construction of hydroelectric power plants and dams requires huge investment. According to the International Hydropower Association’s 2017 Hydropower Status Report, an estimated 31.5 gigawatts (GW) of hydropower capacity was put into operation in 2016, bringing the world’s cumulative installed capacity to 1,246 GW
According to the World Coal Association, coal-fired power plants accounted for about 37% of global electricity in 2018, with China possessing the world’s largest fleet. Coal-fired power plants use steam coal as a source to generate electricity and consequently emit a significant amount of harmful gases into the atmosphere.
A gas-fired power plant burns natural gas – a rapidly growing energy source across the world – to generate electricity. Although natural gas is a fossil fuel, the emissions produced from its combustion are much lower than those from coal or oil, according to a study by the Union of Concerned Scientists. Data from the International Energy Agency (IEA) shows that gas-fired power generation expanded by 3% in 2019, taking its power generation in the global mix to 23%.
In recent years, there has been a rapid growth in the number of wind farms across the world, underpinned by technological advancements. Global installed wind-generation capacity onshore and offshore has increased by a factor of almost 75 in the past two decades, jumping from 7.5 GW in 1997 to 564 GW by 2018, according to the IRENA. After the wind turbines are built, operational costs involved in maintaining wind power plants are low and they are generally considered to be relatively cost-effective.
Solar energy plants convert energy from the sun into thermal or electrical energy using one of the cleanest and most abundant renewable energy sources. They generally do not require high maintenance and last for about 20 to 25 years. According to the International Renewable Energy Agency (IRENA), global solar power capacity will increase by 9% each year between 2018 and 2050, in which time it will grow from 480 GW to more than 8,000 GW.