Sustainable Energy

A Solar Field for a Hybrid Power Plant

How solar-thermal energy could trim coal plants’ carbon footprint.

Feb 9, 2009
Flagsol GmbH, a technological subsidiary of Solar Millennium, has received the contract for the design and supply of the solar field for a hybrid power plant in Egypt. The solar field will be completed in cooperation with Orascom Construction Industries, a large Egyptian general contractor in Cairo, for NREA, the Egyptian authority responsible for renewable energy. The total cost of the hybrid power plant is over $320 million, and approximately 30 percent of that applies to the solar field. The Global Environment Facility is providing a subsidy of $50 million. According to plans, construction will take 30 months. Flagsol and Orascom Construction Industries will operate the plant for two years, before it is finally handed over to the end owner.

These assemblies of parabolic mirrors installed by German engineering firm Flagsol in Kuraymat, Egypt, mark the beginnings of a solar-thermal energy collector field that will span 130,000 square meters. Solar heat collected in the field will be combined with combustion of natural gas in a 150-megawatt hybrid power plant under construction at the site south of Cairo.
Glass tubes filled with heat-transfer fluid will be mounted above the mirrors to absorb the focused sunlight. The heat-transfer fluid will be pumped to the power plant, where it will generate steam to drive a steam turbine.
By the time the plant is operating next summer, a total of 53,000 mirrors will gather enough solar heat to generate about 20 megawatts of power.
The hybrid power plant at Kuraymat will operate 24-7, since its solar-thermal collectors are just one of two sources of energy. When the sun goes down, it will continue generating power by burning natural gas.
This hybrid power plant is the first of its kind in Egypt but not the only one in the region. Similar hybrid solar-thermal/natural-gas power plants are under construction in Algeria and Morocco and under consideration in California.