The DLOOP is a structure of non-overlapping tiles (typically
corner connected) occupying two layers. Interest in the DLOOP
arises from Photo-Voltaic (PV) tracking applications.
The tiles (PV modules) of contemporary tracking systems are
within one contiguous layer, i.e. a side-by-side platform (SSP).
Trees collect solar energy using branching structures to support
leaves which are, similar to PV modules, planar surfaces of solar
energy transformation. The tree's form is naturally excellent for
lowering structural stress in limbs and thermal stress in leaves.
For analogous reasons, related to the creation of flow paths that
would otherwise be blocked, this research hypothesised (and has
subsequently shown) that:
* the fluid (wind) dynamic force on tiles of high inclination SSP
may be reduced (up to 30%) adopting DLOOP arrangements; and
* the temperature of heated tiles in SSP may be reduced (up to 5K
within nominal and hot terrestrial environments), by passive
convective cooling, adopting DLOOP arrangements.
Fluid (wind) dynamic force is significant in PV applications
because it typically exceeds the force of gravity on the tiles of
SSP in 13m/s winds and increases with velocity squared. Hence
reducing wind force by 30% should allow 40% more tiles to be
fitted to contemporary tracking mechanisms.
Temperature is significant in PV applications because the
performance of PV tiles typically falls 0.4%/K. Hence a 5K
reduction in temperature should improve efficiency 2%.
A combination of wind-tunnel tests, Particle Image Velocimetry
and Computational Fluid Dynamic (CFD) simulations using Reynolds
Averaged Navier Stokes and Large Eddy Simulation turbulence
models was used for the fluid dynamic research.
A combined Finite Element/CFD simulation of PV panels in
platforms was developed to model temperature outcomes of thermal
diffusion in solid materials and thermal diffusion, radiation and
convection in the fluid (air).
If PV-tracking ranges are limited below those of the
solar-vector, shading of the DLOOP lower by the upper layer
occurs. This DLOOP self-shading raises unique cost-benefits
associated with tracking ranges. Consequently, this research
develops a means to quantify the insolation received by platforms
accounting for technology and tracking range in diverse
(Australian) climates.
Additionally, multiple tracking platforms may be placed in close
proximity and suffer "Parasitic" energy losses when shaded by
self-similar neighbours. Therefore, this research study
introduces a natural no-shade scale to describe and optimise
field layouts according to local insolation and economic
conditions
