In May 2011, in Spain, was commissioned in solar thermal power plant, which concentrates solar energy using mirrors and store it in the form of heat at night and even during periods of low insolation. In an average year, it is able to work 6400 hours, which is three to four times more than the norm for such structures in this climate zone.
GelioTES Gemasolar, owned by Torresol Energy, — the world's first commercial geoliotermalnaya station with heat storage in the molten salts. As conceived by the designers, it is designed to demonstrate the ability to store large amounts of energy for a long time. Now, at the end of the winter of 2011-2012, the test can be considered successfully passed: the average capacity factor was 74% power. Such stories in solar thermal and solar plants is the first time.
Around this central tower gelioTES having a height of 140 meters, placing 2650 reflecting mirrors, each of which has a surface area of 120 m². The total area of power — 195 hectares (1.85 km ²), although the area of the reflecting mirrors (effective area of solar collectors) — total 304,000 m². Building, located in the municipality of Fuentes de Andalucía (Seville province), is the first commercial power plant of this type, designed for round the clock work greater rigor of the year.
Power station is small — only 19.9 MW, but the annual output of 110 GW • h And it is not a theory, but the bottom line over the past 9 months (annualized). Although the year of continuous work is not yet over, but the worst part for solar power is over: the length of daylight increases — and thus, by May weighted average station can only increase.
The key point of the project — is thereby Gemasolar can produce so much energy. The station works (although not always at full power) 6400 hours a year of 8670 hours total time, with a capacity factor of 74%. For energy storage for night-time and non-durables sunless periods (winter) used container with molten salts that have been circulating at temperatures up to 560? C. Thermal receiver stores up to 600 MW • hour of energy that operates the station up to 15 hours without any sunlight. Thus, more than four months of the year, from May to September, gelioTES operates around the clock at maximum capacity. And even from October to April can work harder for other stations of this type without the storage tank (up to 14 hours on sunny winter days.)
Molten salt heat the water in the secondary circuit, and produced with low-temperature steam turns a turbine. According to the statement, the two containers of molten salts with relatively small: they only 6250 tons, for heat storage capacity of 600 MW • hour is not much. Practical efficiency of the station is 18%, it is this part of the sunlight falling on the mirrors, converted to electricity.
Gemasolar construction cost was approximately € 200 million ($ 260 million, including the settlement of land issues), which provides more than $ 13 thousand per kilowatt of installed capacity. Of course, this figure is slightly deceiving: no ordinary Solar thermal power plants or solar panels on the solar cells are not working 6 400-6 500 hours a year, so a direct comparison of the cost of the input power is inapplicable here. Even the representatives of Gemasolar recognize that they had to order his special turbines and thermal equipment, since conventional thermal power plants have very different parameters of the coolant. Naturally, the cost of the individual order exceeds the normal industry prices, but the massive construction of such stations would greatly improve the price situation.
Will this be the basis for the construction of cyclopean power of Spain, who is now only the second place in Europe for solar energy generated?
In particular, the operating staff is rested on the lack Gemasolar need fuel. Santiago Arias, managing gelioTES, and notes that in 2003, when the project started, everyone thought Torresol Energy cranks, invest in "green", but the non-profit project. "But then a barrel of oil cost $ 28, but now he is more than $ 120. Allow the power industry for 10 years in the same spirit, and already they seem eccentric." According to Mr. Arias, after only 18 years after the start of operation of the plant operator intends to pay all the borrowed money. And then "Gemasolar be printing press, producing tysyacheevrovye bills." According to the manager, even the most dramatic decline in prices for photovoltaic cells gelioTES not close the road to the future, because the electrical energy commercially viable yet, but hundreds of MW thermal receiver is not only possible, but already operational.