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CONSTRUCTION WORLD
SEPTEMBER
2017
48
ALTERNATIVE POWER
Engenamic, with their team’s leading
specialist professional engineering
expertise in the field of lightning safety
and lightning protection, observe that there
are particular general characteristics of
such sites and applications that contribute
to their exposure and vulnerability to the
deleterious effects of lightning.
Engenamic CEO and principal advisor/
consultant Ian McKechnie noted that “in
particular, they present a complex site
and application environment, and this
complexity impacts directly on the broad-
based risks and engineering (and other)
management challenges associated with
lightning safety and lightning protection”.
Engenamic noted that these are
typically large and geographically extended
sites, with factors such as the extensive
interconnected electrical and electronic
equipment and system elements adding
to the complexity and challenges to be
addressed and managed in a holistic and
integrated manner. Often these sites are
located in areas with difficult grounding
conditions such as poor soil resistivities,
which together with the extended and
interconnected nature of these plants, adds
to the challenges presented in respect
of ground potential rises and differential
voltages across the site and between
elements, and consequent risks to the
interconnected systems and equipment.
Plant equipment is also relatively
exposed to both direct strikes and to the
induced effects of the electromagnetic
fields associated with lightning strikes.
Engenamic commented, for example, that
these fields can potentially affect and
damage buried services (such as cables)
as well as above-ground equipment.
The damage to buried services (such as
insulation damage) can also potentially
only become apparent at a later stage
(‘latent damage’).
Engenamic also stated that while plants
of this nature might not be extensively
manned, this can vary during different
times (for example during construction and
maintenance) and the risks associated with
injury must still be carefully considered, in
addition to the risk of economic loss.
On the topic of risk, Engenamic noted
that the nature and characteristics of such
plants required a careful consideration of
the risk assessment methodology, including
the judicious use of risk areas or zones as
appropriate. In particular a qualitative risk
assessment should inform any quantitative
assessment (with appropriate selection
of parameters), as well as form part of a
‘broad-based’ risk assessment.
McKechnie commented that the nature
of such plants and the associated risks
emphasises the need for an effective,
holistic lightning protection solution
that is coherent across all aspects.
Important aspects and elements of such a
solution include, for example, direct strike
protection, site-wide equipotentialisation,
and the careful, considered and consistent
definition and application of lightning
protection zones (and of their boundary
management) – the latter includes the
appropriate and coherent application of
surge protection as well as appropriate
cabling practices (including shielding).
Engenamic professional team members
have been at the forefront of developing
and internationally publishing a structured
systems engineering and strategic
approach to holistic lightning safety and
protection solutions. Engenamic advocates,
in principle, the use of such an approach
philosophy, tailored to the application and
applied through the use of appropriate
professional expertise, as key to achieving
effective and sustainable lightning safety
and protection solutions.
Engenamic’s professional services are
offered and available internationally on a
worldwide basis. In addition to engineering
and project consulting, these services also
include the Engenamic team’s particular
expertise and experience in ‘troubleshooting
and fixing’, including forensic engineering,
and dispute resolution support.
Engenamic professional team members
are also available for appointment as
mediators and adjudicators.
Solar plants –
MANAGING
the
LIGHTNING RISK
Solar plants, particularly (but
certainly not only) large facilities
such as utility-scale PV plants,
present particular challenges in
respect of lightning protection.
Engenamic CEO, Ian McKechnie.
The nature and characteris-
tics of such plants required a
careful consideration of the
risk assessment methodol-
ogy, including the judicious
use of risk areas or zones
as appropriate.