Pumped-storage hydroelectricity (PSH), or pumped hydroelectric energy storage (PHES), is a type of hydroelectric energy storage used by electric power systems for load balancing. A PHS system stores energy in the form of gravitational potential energy of water, pumped from a lower elevation reservoir to a higher elevation. Low-cost surplus off-peak electric power is typically used to run the pumps. During periods of high electrical demand, the stored water is released through turbines to produce electric power.
The Dinorwig Power Station, known locally as Electric Mountain, or Mynydd Gwefru, is a pumped-storage hydroelectric scheme, near Dinorwig, Llanberis in Snowdonia national park in Gwynedd, north Wales. The scheme can supply a maximum power of 1,728 MW (2,317,000 hp) and has a storage capacity of around 9.1 GWh (33 TJ).
The HVDC Cross-Channel is the 73-kilometre-long (45 mi) high-voltage direct current (HVDC) interconnector that has operated since 1986 under the English Channel between the continental European grid at Bonningues-lès-Calais and the British electricity grid at Sellindge. The cable is also known as IFA, and should not be confused with the new IFA-2, another interconnect with France that is three times as long but only half as powerful.
The National Grid is the high-voltage electric power transmission network serving Great Britain, connecting power stations and major substations, and ensuring that electricity generated anywhere on the grid can be used to satisfy demand elsewhere. The network serves the majority of Great Britain and some of the surrounding islands. It does not cover Northern Ireland, which is part of the Irish single electricity market.
India is the third largest producer of electricity in the world. During the fiscal year (FY) 2023–24, the total electricity generation in the country was 1,949 TWh, of which 1,734 TWh was generated by utilities.
Grid energy storage is a collection of methods used for energy storage on a large scale within an electrical power grid. Electrical energy is stored during times when electricity is plentiful and inexpensive or when demand is low, and later returned to the grid when demand is high, and electricity prices tend to be higher.
The Electric Reliability Council of Texas, Inc. (ERCOT) is an American organization that operates Texas's electrical grid, the Texas Interconnection, which supplies power to more than 25 million Texas customers and represents 90 percent of the state's electric load. ERCOT is the first independent system operator (ISO) in the United States. ERCOT works with the Texas Reliability Entity (TRE), one of six regional entities within the North American Electric Reliability Corporation (NERC) that coordinate to improve reliability of the bulk power grid.
Demand response is a change in the power consumption of an electric utility customer to better match the demand for power with the supply. Until the 21st century decrease in the cost of pumped storage and batteries, electric energy could not be easily stored, so utilities have traditionally matched demand and supply by throttling the production rate of their power plants, taking generating units on or off line, or importing power from other utilities. There are limits to what can be achieved on the supply side, because some generating units can take a long time to come up to full power, some units may be very expensive to operate, and demand can at times be greater than the capacity of all the available power plants put together. Demand response, a type of energy demand management, seeks to adjust in real-time the demand for power instead of adjusting the supply.
The United Kingdom is the best location for wind power in Europe and one of the best in the world. The combination of long coastline, shallow water and strong winds make offshore wind unusually effective.
Hybrid power are combinations between different technologies to produce power.
India's solar power installed capacity was 90.76 GW AC as of 30 September 2024. India is the third largest producer of solar power globally.
Load management, also known as demand-side management (DSM), is the process of balancing the supply of electricity on the network with the electrical load by adjusting or controlling the load rather than the power station output. This can be achieved by direct intervention of the utility in real time, by the use of frequency sensitive relays triggering the circuit breakers, by time clocks, or by using special tariffs to influence consumer behavior. Load management allows utilities to reduce demand for electricity during peak usage times, which can, in turn, reduce costs by eliminating the need for peaking power plants. In addition, some peaking power plants can take more than an hour to bring on-line which makes load management even more critical should a plant go off-line unexpectedly for example. Load management can also help reduce harmful emissions, since peaking plants or backup generators are often dirtier and less efficient than base load power plants. New load-management technologies are constantly under development — both by private industry and public entities.
The electricity sector in New Zealand uses mainly renewable energy, such as hydropower, geothermal power and increasingly wind energy. As of 2021, the country generated 81.2% of its electricity from renewable sources. The strategy of electrification is being pursued to enhance the penetration of renewable energy sources and to reduce greenhouse gas (GHG) emissions across all sectors of the economy. In 2021, electricity consumption reached 40 terawatt-hours (TW⋅h), representing a 0.2% increase compared to the consumption levels in 2010.
The Cruachan Power Station is a pumped-storage hydroelectric power station in Argyll and Bute, Scotland, UK. The scheme can provide 440 MW of power and produced 705 GWh in 2009.
The National Grid covers most of mainland Great Britain and several of the surrounding islands, and there are interconnectors to Northern Ireland and to other European countries. Power is supplied to consumers at 230 volts AC with a frequency of 50 Hz. In 2023 about a third of electricity used in Britain was generated from fossil gas and two-thirds was low-carbon power. Wind generates the most low-carbon power, followed by nuclear some of which is imported from France. The government is aiming for greenhouse gas emissions from electricity in Britain to be net zero by 2035.
South Australia is a leader in utility-scale renewable energy generation, and also produces gas and uranium for electricity generation. Gas production is mostly concentrated in the Cooper Basin in the state's north-east. Gas is delivered from these fields by pipeline to users interstate and to Port Adelaide where it fuels three separate gas-fired power plants. Uranium is also mined in South Australia, though nuclear power generation is prohibited nationally. The Olympic Dam mine is the world's single largest known deposit of uranium and represents 30% of the world's total uranium resource. Many utility-scale wind farms and solar farms have been commissioned during the 21st century and geology with potential for geothermal energy has also been identified but is yet to be developed.
Lithuania is a net energy importer. In 2019 Lithuania used around 11.4 TWh of electricity after producing just 3.6 TWh.
Solar power in Denmark amounts to 3,696 MW of grid-connected PV capacity at the end of June 2024, and contributes to a government target to use 100% renewable electricity by 2030 and 100% renewable energy by 2050. Solar power produced 9.3% of Danish electricity generation in 2023, the highest share in the Nordic countries.
The electricity sector in Australia has been historically dominated by coal-fired power stations, but renewables are forming a rapidly growing fraction of supply. In 2021, Australia's electricity production reached 265 TWh, with coal accounting for 52.9% and natural gas for 18.8%. Renewable sources, comprising solar, wind, hydro, and bioenergy with waste, collectively made up 26.7% of the total electricity generation mix.
