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sustainable construction world
don’t compensate well for excess electricity
that is exported onto the grid. A rooftop plant
should be incorporated into an organisation’s
long term operational plan in order to optimise
the business case. We always recommend that
we optimise the PV plant size to what the load
should be, not necessarily what it is currently,”
said Turner.
Advantages
There are a number of advantages to incorp-
orating PV into building design at inception:
1. Incorporating solar power into the original
concept and plans will result in a system that is
aesthetically integrated into the overall design
and simpler to install.
“Well-integrated plants can add to the
appearance of a building, and by planning
ahead, the available roof area can be designed
to accommodate the optimal size plant with
simplified cable routing, and objects on the roof
such as chimneys and aerials can be placed
where they won’t impact the performance of the
PV plant.”
2. In roof PV installations, the building will be
designed to carry the weight of the PV plant, as
well as optimising roof angles to get maximum
solar exposure.
“It tends to cost more to add PV post-build
than incorporating a PV plant in the original
design. When working on existing buildings,
if the original roof was not designed to carry
the additional load of a PV plant, the cost of
strengthening the roof can negatively impact the
business case.”
3. A PV plant that is planned upfront can be better
integrated with back-up power solutions
“By adopting a holistic systems view when
designing a building, a PV plant can be better
integrated with available back-up generation
and storage technologies, reducing costs and
improving operations. This is important as
business owners grapple with the challenge
of energy security and cost-effective solutions
to loadshedding”
4. It is often easier to combine the cost of the
rooftop PV plant into upfront asset financing
structures than to finance these projects at a
later stage.
“Although juwi doesn’t cater to the residential
solar market, it is probably easiest to use the
example of a residential PV system to illustrate
this. A R100 000 solar energy solution would be
easy to absorb into the original bond amount
if it was integrated from conception, whereas
financing this amount without a secured loan at
a later stage can be more complex. It’s almost
always cheaper and easier to finance upfront,”
says Turner.
With the rapidly increasing cost of electricity
in SA, RE is the logical next step for those
companies that have already implemented all
economically viable energy efficiency initiatives.
According to Turner, juwi has been able to
undercut tariffs of 80 - 90 cents per kWh, which
“is exciting, because it opens up a huge market
for rooftop solar all over South Africa”.
∞