Of Sunflowers and Solar Plants

When looking for ways to increase solar energy efficiency, MIT researchers simply stopped and smelled the…sunflowers.

Using the flower as inspiration, a team of researchers led by Professor Alexander Mitsos developed a solar panel layout that mimics the arrangement of sunflower florets, a pattern called Fermat’s spiral.

From MIT News:

“The MIT team…looked to nature for inspiration — specifically, to the sunflower. The florets of a sunflower are arranged in a spiraling pattern, known as a Fermat spiral, that appears in many natural objects and has long fascinated mathematicians: The ancient Greeks even applied the patterns to buildings and other architectural structures. Mathematicians have found that each sunflower floret is turned at a ‘golden angle’—about 137 degrees—with respect to its neighboring floret.”

The new layout takes up to 20 percent less space than Spain’s PS10 Solar Power Plant, Europe’s first concentrated solar power plant, which can covert enough electricity to power 6,000 homes.  Compared with the PS10’s configuration, where mirrors are arranged around in circles and the distance between mirrors akin to the seats in a movie theater, the new layout reduces shading and blocking, and increases total efficiency.

The research team, which includes Corey Noone SM ’11 and Manuel Torrihon of RWTH Aachen University in Germany, found that their new pattern could reduce shadowing and blocking throughout the day. Their findings were published in the journal Solar Energy, and the team has recently filed for patent protection.

From MIT News:

“…the spiral pattern reduced shading and blocking and increased total efficiency compared with PS10’s radially staggered configuration.

Mitsos says arranging a CSP plant in such a spiral pattern could reduce the amount of land and the number of heliostats required to generate an equivalent amount of energy, which could result in significant cost savings.”