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. The method 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. Although the losses of the pumping process make the plant a net consumer of energy overall, the system increases revenue by selling more electricity during periods of peak demand, when electricity prices are highest. If the upper lake collects significant rainfall or is fed by a river then the plant may be a net energy producer in the manner of a traditional hydroelectric plant.
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 km long high-voltage direct current (HVDC) interconnector that operates 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.
In the electricity sector in the United Kingdom, 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 it can be used to satisfy demand elsewhere. The network covers the great majority of Great Britain and several of the surrounding islands. It does not cover Northern Ireland, which is part of a single electricity market with the Republic of Ireland.
India is the third largest producer of electricity in the world. During the fiscal year (FY) 2021–22, the total electricity generation in the country was 1,719 TWh, of which 1,484 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 eight regional entities within the North American Electric Reliability Corporation (NERC) that coordinate to improve reliability of the bulk power grid.
Hybrid power are combinations between different technologies to produce power.
Solar power is a fast developing industry in India. The country's solar installed capacity was 63.303 GWAC as of 31 December 2022. Solar power generation in India ranks fourth globally in 2021.
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 Cruachan Power Station is a pumped-storage hydroelectric power station in Argyll and Bute, Scotland. The scheme can provide 440 MW of power and produced 705 GWh in 2009.
The United Kingdom has a National Grid that covers most of mainland Great Britain and several of the surrounding islands, as well as some connectivity to other countries. The electrical sector supplies power at 50 Hz AC, and ~240 volts is supplied to consumers. In 2020 the electricity sector's grid supply came from 55% low-carbon power, 36.1% fossil fuelled power, and 8.4% imports. Renewable power is showing strong growth, while fossil fuel generator use in general and coal use in particular is shrinking, with historically dominant coal generators now mainly being run in winter due to pollution and costs, and contributed just 1.6% of the supply in 2020.
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. Primary energy use in Lithuania was 98 TWh, or 29 TWh per million people in 2009.
As of 2018, hydroelectric power stations in the United Kingdom accounted for 1.87 GW of installed electrical generating capacity, being 2.2% of the UK's total generating capacity and 4.2% of UK's renewable energy generating capacity. This includes four conventional hydroelectric power stations and run-of-river schemes for which annual electricity production is approximately 5,000 GWh, being about 1.3% of the UK's total electricity production. There are also pumped-storage hydroelectric power stations providing a further 2.8 GW of installed electrical generating capacity, and contributing up to 4,075 GWh of peak demand electricity annually.
Solar power in Denmark is at 2,339 MW (grid-connected) by mid-2022, and contributes to a goal to use 100% renewable energy by 2050. The goal of 200 MW of photovoltaics by 2020 was reached eight years early, in 2012, and 36 MW was being installed each month. Denmark had 790 MW in late 2015. A total of 3,400 MW is expected to be installed by 2030. Many solar-thermal district heating plants exist and are planned in Denmark.
Energy in California is a major area of the economy of California. California is the state with the largest population and the largest economy in the United States. It is second in energy consumption after Texas. As of 2018, per capita consumption was the fourth-lowest in the United States partially because of the mild climate and energy efficiency programs.
The Australian electricity sector has been historically dominated by coal-fired power stations, but renewables are forming a rapidly growing fraction of supply.
A battery storage power station is a type of energy storage power station that uses a group of batteries to store electrical energy. Battery storage is the fastest responding dispatchable source of power on electric grids, and it is used to stabilise those grids, as battery storage can transition from standby to full power in under a second to deal with grid contingencies.
