386. New Solar Power Plant Can Generate Electricity at Night

By Terrence Aym, Setyoufree News, June 13, 2011

Torresol Energy, a bold joint venture between the Spanish engineering firm SENER and an Abu Dhabu energy company called Masdar has accomplished a feat few in the energy production business thought possible scant years ago: a solar powered facility that generates electricity at night.

Employing a unique solution to the problem that has stymied legions of engineers for decades, the two firms designed a maverick system designed to skirt the problem presented by nighttime.

Using a gigantic array of solar mirrors, called heliostats, laid out in a circular pattern, the Gemasolar Power Plant located near Seville, Spain reflects sunlight off its 2,650 panels onto a huge receiver located at the epicenter of the plant.

The highly polished mirrors, trained on the locus at the center, efficiently reflect as much as 95 percent of the solar radiation. In turn, the incredible thermal energy that's captured is directed towards tanks containing molten salt. As the salt heats from the heat—sas high as 1650 degrees Fahrenheit—superheated, highly pressurized steam is created. The steam drives the power station's turbines.

Solar powered utilities normally have a great drawback at night: they cannot generate power. But Gemasolar can; it can continue running the turbines and generating electricity for up to 15 hours of darkness by drawing off the stored heat and steam generated within the salt tanks.

Miguel Domingo, a spokesperson for Spain's SENER, told the UK's Daily Mail that "The on-schedule and on-budget completion of the construction and commissioning of the Gemasolar plant is a milestone for SENER. Currently, SENER is the only company in the world that has developed and built a commercial plant with central tower molten salt receiver technology that has already started operation."

Company spokespeople explain that the region of Spain where the power plant is located enjoys sunshine at least 270 days annually. They point out that means Gemasolar can produce as much as 300 percent more power than other renewable energy technologies. That makes the plant one of the most efficient and reliable green energy producers in the world.

The chairman of Torresol Energy, Enrique Sendagorta, addressed the economics of the plant. He told the Daily Mail "The standardization of this new technology will mean a real reduction in the investment costs for solar plants. The commercial operation of this plant will lead the way for other central tower plants with molten salt receiver technology, an efficient system that improves the dispatchability of electric power from renewable sources."

According to SENER, the plant—that took two years to build and bring to operational status—is expected to power about 25,000 homes. It will accomplish that by generating an impressive 110 gigawatts annually.