Deep Foundations for Solar Arrays
We recently completed extensive design work for the foundations required for Phase
I of a very large (300+ MW) solar project, generating designs for three racking
systems being investigated by the developer. The structural, geotechnical, and environmental
engineering aspects were considered, as well as advanced supply-chain, local component-based
manufacturing, installation, and pricing methodologies. The preliminary criteria,
provided by the racking companies to perform the engineering, included the spacing
of supports, panel layouts, panel angles, and preferred posts. Some wind tunnel
test results were also supplied and used to determine alternate designs.
Four foundation designs for each racking system were developed: a Helical Anchor
(rotary installation), a Wide Flange Pile, a Pipe Pile, and a Pipe Pile with accompanying
wind test results (all vibration installation).
In summary, the installed cost of each of the four foundation designs, ranging from
$11.70 - $22.96 per ft, is significantly less than the installed cost of a concrete
pile, which can easily run over $45 per ft.
In addition, the total cost per foundation of the four designs ranges from $176 -
$427 (with an average of $285), also significantly less than the $450+ total cost
of the 10 ft. driven concrete pile previously assumed. This represents a difference,
when multiplied by the hundreds of thousands of foundations necessary for all phases
in the project, equating to tens of millions of dollars.
Click on the document below and read about the 'Engineered Difference' we bring
to providing foundations for solar projects. Included in the document are graphics
of sample designs, as well as a set of optional connections to racking systems.
It just may be the 'difference' your project will need!