Energy storage is the capture of energy produced at one time for use at a later time to reduce imbalances between energy demand and energy production. A device that stores energy is generally called an accumulator or battery. Energy comes in multiple forms including radiation, chemical, gravitational potential, electrical potential, electricity, elevated temperature, latent heat and kinetic. Energy storage involves converting energy from forms that are difficult to store to more conveniently or economically storable forms.
A power station, also referred to as a power plant and sometimes generating station or generating plant, is an industrial facility for the generation of electric power. Power stations are generally connected to an electrical grid.
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.
Hydroelectricity, or hydroelectric power, is electricity generated from hydropower. Hydropower supplies one sixth of the world's electricity, almost 4500 TWh in 2020, which is more than all other renewable sources combined and also more than nuclear power. Hydropower can provide large amounts of low-carbon electricity on demand, making it a key element for creating secure and clean electricity supply systems. A hydroelectric power station that has a dam and reservoir is a flexible source, since the amount of electricity produced can be increased or decreased in seconds or minutes in response to varying electricity demand. Once a hydroelectric complex is constructed, it produces no direct waste, and almost always emits considerably less greenhouse gas than fossil fuel-powered energy plants. However, when constructed in lowland rainforest areas, where part of the forest is inundated, substantial amounts of greenhouse gases may be emitted.
The Eildon Dam is a rock and earth-fill embankment dam with a controlled spillway across the Goulburn River, is located between the regional towns of Mansfield and Eildon within Lake Eildon National Park, in the Alpine region of Victoria, Australia. The dam's purpose is for the supply of potable water, irrigation, and the generation of hydroelectricity. The impounded reservoir is called Lake Eildon.
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.
Peaking power plants, also known as peaker plants, and occasionally just "peakers", are power plants that generally run only when there is a high demand, known as peak demand, for electricity. Because they supply power only occasionally, the power supplied commands a much higher price per kilowatt hour than base load power. Peak load power plants are dispatched in combination with base load power plants, which supply a dependable and consistent amount of electricity, to meet the minimum demand.
Old Hickory Lock and Dam is a dam located in middle Tennessee on the Cumberland River at river mile 216.2 in Sumner and Davidson Counties, approximately 25 miles (40 km) upstream from Nashville. The reservoir behind the dam is Old Hickory Lake. The dam and lake are named after President Andrew Jackson, who lived in the vicinity at The Hermitage.
Nagarjuna Sagar Dam is a masonry dam across the Krishna River at Nagarjuna Sagar which straddles the border between Nalgonda district in Telangana and Palnadu district in Andhra Pradesh. The dam provides irrigation water to the Nalgonda, Suryapet, Krishna, NTR, Bapatla, Eluru, Palnadu, Khammam, West Godavari, Guntur, and Prakasam districts along with electricity generation.
The Shoalhaven Scheme is a dual-purpose water supply and Pumped-storage Hydroelectricity scheme located on the South Coast region of New South Wales, Australia.
The net capacity factor is the unitless ratio of actual electrical energy output over a given period of time to the theoretical maximum electrical energy output over that period. The theoretical maximum energy output of a given installation is defined as that due to its continuous operation at full nameplate capacity over the relevant period. The capacity factor can be calculated for any electricity producing installation, such as a fuel consuming power plant or one using renewable energy, such as wind or the sun. The average capacity factor can also be defined for any class of such installations, and can be used to compare different types of electricity production.
The Murray Region Hydroelectric Power Stations refers to two of the original seven hydroelectric power stations, both located near the town of Khancoban in the Snowy Mountains region of New South Wales, Australia. The two power stations are part of the Snowy Mountains Scheme, a vast hydroelectricity and irrigation complex constructed in south-east Australia between 1949 and 1974 and now run by Snowy Hydro. Although both power stations are physically located in New South Wales, since 1 July 2008 all power generated has been allocated to the Victorian region of the National Electricity Market. The stations are not located on the Murray River.
The Tumut Hydroelectric Power Stations is a series of three hydroelectric power stations on the Tumut River in New South Wales, Australia, that are part of the Snowy Mountains Scheme.
Bear Swamp Generating Station or Jack Cockwell Station is a pumped-storage hydroelectric underground power station that straddles the Deerfield River in Rowe and Florida, Massachusetts. It is one of many hydroelectric facilities along the river, giving that waterway the nickname of "the hardest working river in the county".
Run-of-river hydroelectricity (ROR) or run-of-the-river hydroelectricity is a type of hydroelectric generation plant whereby little or no water storage is provided. Run-of-the-river power plants may have no water storage at all or a limited amount of storage, in which case the storage reservoir is referred to as pondage. A plant without pondage is subject to seasonal river flows, thus the plant will operate as an intermittent energy source. Conventional hydro uses reservoirs, which regulate water for flood control, dispatchable electrical power, and the provision of fresh water for agriculture.
A load-following power plant, regarded as producing mid-merit or mid-priced electricity, is a power plant that adjusts its power output as demand for electricity fluctuates throughout the day. Load-following plants are typically in between base load and peaking power plants in efficiency, speed of start-up and shut-down, construction cost, cost of electricity and capacity factor.
The Siah Bisheh Pumped Storage Power Plant, also spelled Siyāhbisheh and Siah Bishe, is located in the Alborz Mountain range near the village of Siah Bisheh and 48 km (30 mi) south of Chalus in Mazandaran Province, Iran. The power plant uses the pumped-storage hydroelectric method to generate electricity during periods of high energy demand, making it a peaking power plant, intended to fulfill peak electricity demand in Tehran 60 km (37 mi) to the south. When complete it will have an installed generating capacity of 1,040 megawatts (1,390,000 hp) and a pumping capacity of 940 megawatts (1,260,000 hp). Planning for the project began in the 1970s and construction began in 1985. It was delayed from 1992 until 2001 and the first generator went online in May 2013. The remaining generators were commissioned by 1 September 2015. The power plant is the first pumped-storage type in Iran and will also use the country's first concrete-face rock-fill dam – two of them.
Castaic Power Plant, also known as the Castaic Pumped-Storage Plant, is a seven unit pumped-storage hydroelectric plant, operated by the Los Angeles Department of Water and Power, which provides peak load power from the falling water on the West Branch of the California State Aqueduct. It is a cooperative venture between the LADWP and the Department of Water Resources of the State of California. An agreement between the two organizations was signed on September 2, 1966, for construction of the project.
Variable renewable energy (VRE) or intermittent renewable energy sources (IRES) are renewable energy sources that are not dispatchable due to their fluctuating nature, such as wind power and solar power, as opposed to controllable renewable energy sources, such as dammed hydroelectricity or biomass, or relatively constant sources, such as geothermal power.
Northfield Mountain is a pumped-storage hydroelectric plant and reservoir located on and under the similarly named Northfield Mountain in Erving and Northfield, Massachusetts. It is currently owned by FirstLight Power Resources, which purchased the facility from Northeast Utilities in 2006.
