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Wind and solar farms
have come up to be popular sources of renewable energy in
many parts of the world, in addition to other renewable
energy sources. The province of Ontario in Canada has turned
out to be one of the most popular locations for setting up
renewable energy facilities because of its strong
initiatives for sustainable policies and development along
with attractive rates offered for renewable energy through
Ontario Hydro’s popular Feed In Tariff (FIT) Program. In
addition to wind, numerous Solar PV Farms have been
completed; many are under construction while still more are
in planning and permitting stage in this province, varying
from 3MW to up to 260MW located in the suburbs of cities and
towns which are being benefited from these renewable energy
sources. Winter conditions and extreme frost in certain
areas in Ontario poses unique issues with construction of
such utility scale farms. Typical ground mounted
construction comprises of solar PV panels mounted on racking
tables supported on foundations usually comprising of
partially embedded steel pipes while foundations for
inverter houses, control houses, transformer foundations and
substation structures are either concrete pads or piles.
While the substation structures, I-House and E-House
foundations have well defined design procedures regulated by
different codes and standards, the procedures, codes and
standards for design and testing of lightly loaded solar PV
structures still need to be formulated. In the absence of
any specific codes and standards regulating the design
aspects of these lightly loaded solar PV structures with
frost uplift being the governing load in almost every case
for Ontario, Canada, frost heaving and its effects are not
very well understood and often create adverse conditions for
these structures thereby affecting the production and
continuous supply of renewable energy to the cities and
towns in vicinity who purchase this energy. This study
investigates these unique issues related with renewable
energy farms which are presented in this paper. The authors
have been involved in design reviews, pile selection/ design
and pile load testing in the majority of the solar PV farms
either operational or under construction in Ontario along
with being involved with the rehabilitation of farms
affected by pile heaving issues. This paper carries out a
critical study on the available design and installation
procedures for lightly loaded pile foundations in the
Canadian codes, regulations and engineering practices along
with a review on the associated research on such
foundations. Possible design, installation and testing
procedures are also suggested to cater for such harsh
conditions.
Keywords: Renewable Energy, Solar PV Farms, Solar Racking,
Racking Foundation, Panel Tables, Solar Panels
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