Inside Cestas

300 MW Cestas project 300 MW Cestas project
To provide the context of the scale of Cestas, the size of a football field is indicated by the small red rectangle alongside the vast PV plant.
Such challenges applied not only to
the inverters, but also the substation that
Schneider Electric supplied. The plant
connects directly to a 225 kV transmission
line, and as such required a significant
step-up in voltage. Such high voltages
allow for less power lost in transit,
but also require specialized components,
and higher voltages mean greater safety
risks. In supplying the substation, Schneider
Electric stresses its mastery of supply
chain issues. The company notes that the
lead times for high-voltage transformers
are in the range of 10 to 12 months. As a
result, any delays could seriously impact
the economics of the project.
Finally, there were considerations due
to the east-west orientation of the modules.
“The integration to the grid is quite
interesting because the load curve will get
wider and a bit more flat, compared to
standard south[-facing] design,” explains
de Prest. “So I think that the production
curve is closer to the consumption, to the
daily consumption curve.”
O&M
De Prest says that an advantage in securing
the contract for the project was
its ability to offer a complete solution,
including a competitive operations and
maintenance (O&M) package, in collaboration
with Eiffage subsidiary Clemessy
and Krinner.
“On such a volume, O&M can make a
big difference,” notes de Prest. “In France,
the customer never retains a technical
solution without also securing the maintenance
plan.”
Schneider Electric maintains a service
center in Bordeaux, only 20 kilometers
from Cestas, and is keeping parts on
hand in the event that replacements are
needed. The company has also dedicated
full-time staff to manage the project.
While de Prest notes that it does not
have a major impact, Schneider Electric
must also consider the plant’s atypical
output profile due to the east-west
orientation of the modules. “What we
have achieved in terms of optimizing the
maintenance has probably been a key
point as well in winning this project,”
concludes de Prest.
A global showroom
De Prest alludes to the ambition of the
Cestas project, noting that it was a “big
challenge”, even for Schneider Electric.
However, the issues that the company
faced may be less unique than indicative
of the directions in which utility-scale
solar is headed.
With fewer nations employing feed-in
tariffs and solar PV competing in more
locations with fossil fuels directly on
price, cost considerations are critical.
Also, as more PV is deployed there will be
more pressure to align the output of projects
to daily demand curves, and as such
the east-west orientation of the modules
may be an indicator of changes to come.
And so aside from the economic value
of the contract, the project is of benefit to
the company as a way to demonstrate its
many offerings. “We are creating a kind
of large-scale showroom of our capabilities,”
states de Prest.
This showroom is global. While
Schneider Electric’s history and headquarters
are in France and it is part of
a distinctly French consortium on the
Cestas project, it is a global company and
supplier to the global PV market. “Today,
we have almost no customers in France
for utility-scale projects that are active
only in France,” notes de Prest.
“We can supply this capability for
such a project, in another country – in
whatever country in the world. Where
you have solar projects in the country,
the capabilities of Schneider will also be
competitive.”
Components supplied by Schneider Electric include 200 of its PV Box RT units, each of which houses two Conext Core XC 680 inverters, including its Conext
Control monitoring solution.
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