Hello again. You might remember my "Ballad of Greg Watson" which made
gentle fun of the wild claims for Sunball and Suncube.
I'd like to settle an argument about the oft repeated claims that CPV
generates more energy per acre and is therefore much better for
commercial rooftops, solar farms etc.
The triple junction cells used in CPV are claimed to have twice the
efficiency of silicon but require 2 axis tracking.
My understanding is that for a single collector a tracker will give
about a 30-40% improvement in collection over the year compared to a
fixed panel (depends somewhat on the location).
However if using multiple collectors e.g. solar farms then adequate
spacing must be allowed to prevent shadowing.
My contention is that because CPV requires 2 axis trackers the spacing
requirement means less power will be produced per acre than can be
obtained from a fixed flat panel array.
David Williams wrote:
True, but then near the equator, with the sun high in the sky, a simple flat
panel non-tracking collector would have a higher output as well.
So the question still remains, does the dual tracking version really buy you
that much more output than simple flat panels when talking a large land area