Explainer: what is hydroelectricity?

● By Prof. Vladimir Strezov, Macquarie University (Austrailia) ● Hydroelectricity is an established power-generation technology with over 100 years of commercial operation. Hydroelectricity is produced when moving water rotates a turbine shaft; this movement is converted to electricity with an electrical generator. According to Euromonitor, hydroelectricity made up 17% of the total world electricity production in 2012. The top four largest electricity producing power stations in the world are all hydroelectric: the Three Gorges in China (18.5 GW), Itaipu in Brazil (14.8 GW), Guri in Venezuela (10.1 GW) and Tucuri in Brazil (8.4 GW). Australia has more than 100 hydroelectric power stations, with the majority located in New South Wales and Tasmania. The annual production of hydroelectricity in Australia for 2012 was slightly over 6% of the total annual power generation, contributing only 0.4% of the world’s total hydroelectricity production. The largest hydropower station in Australia is Snowy Mountains Hydroelectric Scheme with a capacity of 3.8 GW, representing almost half of the total hydropower capacity in Australia. Hydropower technologies There are three main categories of hydropower technologies: run of river, impoundment, and pumped storage. The run-of-river technology relies on the flow of the river at an elevated point, which, through gravity, is fed to a turbine generator. Impoundment hydropower systems employ one or more dams to store water. The potential energy stored in the dam is converted to electricity by passing the stored water from an elevated point through a turbine generator located at the lower point. Pumped hydropower is a two-dam system, where one dam is installed at a higher point to the other. During off-peak hours when the cost of electricity is low, the water from the lower reservoir is pumped up to the elevated reservoir using electricity from the grid ...Zum vollständigen Artikel
