Tower of Power
Solar tower collects rays
from concentrating mirrors
to drive steam turbine.
As we pulled up to the Abengoa Solar facility an hour’s drive out of Seville, we could see rays of sun reflecting off the solar mirrors lighting up the mist in the air near the collector. The SEPA delegation was treated to two fully operating solar towers, one at 10 MW and another at 20 MW. These towers use steam as the working fluid with the steam running through a GE steam turbine to generate electricity.
Among all the cool experiences in touring the plant, I would rate the trip to the control center at the top. Operators could see the exact thermal profile of the 316 stainless steel heat exchange tubes. Slick. I also took a photo of the giant window-washing machines that run every day. The actual focusing of individual mirrors was not the problem that Abengoa engineers thought it might be.
To give you an idea of the scale of the endeavor, a circular array of 624 tracking mirrors or heliostats concentrate the sunlight up to 600 times onto the receiver located at a tower height of 380 ft (115m).
The SEPA contingent posing
in front of the heliostat field.
This facility takes up 18.5 acres (75,000 sq meters) and generates 24 GW of energy annually. About an hour of capacity of steam can be stored at the facility and back up gas fired steam is available to supplement the sun on cloudy days.
I’ve read about these solar towers before, but seeing is believing.
May 22nd, 2009 at 7:02 pm
Nice reporting! I noticed in the picture that the transmission line towers are very tall. Do you know if this has any thing to do with the solar facilities?
May 27th, 2009 at 4:10 pm
The tower height has to do with the size of the facility and the number of heliostats required to focus the solar energy to the solar receivers. So the larger megawatt plants will by nature will have taller towers.
Thanks for the question.
Leave a Comment
About
Rick is joining a U.S. contingent traveling with the Solar Electric Power Association to tour large-scale grid connected solar installations in Southern Spain. Check out Rick’s daily blog and experience the world of solar that is in the here and now.Categories
Recent Posts
Calendar
Archives
Your Account
Subscribe