Concentrated solar power - slide bearing drives supplant bearing points / Innovative drive technology offers new possibilities for cost reduction in parabolic troughs and Fresnel plants

Nuremberg, Germany (ots) - Driven by the trend of renewable
energies, international solar EPC companies (Engineering, Procurement
and Construction), plant manufacturers, and investors are setting
their focus more and more on large scale solar thermal plants using
CSP technology (Concentrated Solar Power). In countries with a high
number of direct and powerful sunlight hours, CSP plants are being
used to generate heat for the production of electricity, the
operation of seawater desalination plants, and for industrial drying
processes.

By using the slide bearing drives from Inter Control in parabolic
troughs and Fresnel plants, it is possible to support and move pairs
of collectors or segments (supporting structure with mounted
mirrors). Especially in parabolic troughs the synchronous rotation of
many slide bearing drives - a so-called electronic shaft - is
realised. In the process the collectors connected to the drives are
each turned individually by a defined moment and with high precision
towards the actual position of the sun. Also, this technology greatly
reduces the effort to stiffen the support structure of the solar
mirrors.

> High demands of precision and torsional stiffness are required
when using central drives in long support structures <

These days an industrial parabolic trough has a bearing point on a
pylon every twelve metres. On these bearings the support structure -
which is 100 to 120 meters long - is rotated by a central drive
system. The curved mirrors - with a total aperture (span width) of
about six meters - and the absorber tube are mounted to the support
structure. The support structure consists of many collectors which
are connected for the complete length to each other.

With this kind of parabolic trough the support structure has to
ensure that all mirrors are best oriented towards the sun and towards
the absorber tube - this is also required in cases of extreme side
winds. Consequently, the support structure requires a high precision
of orientation and high torsional stiffness along the complete
length. This is necessary for a high yield of today's plants.

> Reduce investment costs by using application optimised
technology <

In addition to the location, the operation time, and the
investment cost, the use of application optimised technology is
important for the economical operation of a CSP plant. Therefore
companies and institutes work on increasing reflexion yields of
mirrors, improving absorption yields of absorber tubes, as well as
optimising materials used which includes cost intensive support
structures.

Additionally, in parabolic troughs a complete system consisting of
special drives, controls and sensors is required. With the drive
technology from Inter Control new possibilities of reducing
investment costs as well as increasing yields can be achieved.

> Potential of drive technology by Inter Control <

Due to the symmetrical design of the housing and the rotating
lateral flange connections, the slide bearing drives are easily
integrated into the customer construction. The drives perform best
when the collectors' mass is centred in the rotation axis of the
drives.

For optimal efficiency the drive rotates the connected trough
segments and, at the same time, regulates the bearing function
between two segments.

By doing so the support structure is divided into many segments.
The segments are oriented separately and most accurately towards the
actual position of the sun. Ideally, the collectors are mounted in
pairs onto one drive.

With this approach a parabolic trough does not have to be
stiffened over the complete length. Only the suitable stiffness from
one bearing point to the next bearing point has to be ensured. As a
consequence the material usage in the support structure is
considerably reduced.

> Multiple benefits of the slide bearing drives <

In contrast to conventional drives the slide bearing drives of
Inter Control have the drive and bearing in one single unit. The
drives are optimised for use in parabolic troughs and Fresnel plants.
They offer a high degree of holding accuracy at high torsion moments,
are extremely robust, and can be configured to a complete drive
system. The drives can be supplied with suitable motor gear
combinations, with integrated limit switches, and with BUS-compatible
angle sensors as well as controls. This means the drive units are
delivered to the construction site ready-for-installation into the
CSP plant.

Today the completely enclosed, durable, and almost
maintenance-free drive units are used for mirror areas of up to 100
square metres. Inter Control's competitive pricing of drive units
leads to a low investment cost to the CSP plant. And the drive units'
high functionality guarantees a highly economical operation.

Each product sold for solar tracking by Inter Control conforms to
the actual European Machine Directive and EMC directive.

About Inter Control

Inter Control was founded in 1964 and is today one of the leading
suppliers of future-oriented electromechanical products and
electronic controls as well as innovative product solutions.

In trusting collaboration with our customers we already supply
drive units for CSP projects in Europe and other parts of the world.

As a medium-sized group of companies with headquarters in
Nuremberg and a worldwide workforce of 600, we provide solutions to
complex tasks in the field of drive, sensor and control technology,
mainly in technically ambitious outdoor applications. We achieve this
by engineering and manufacturing our own products - these are used
worldwide and have been proven a million-fold.

We serve our customers through six international subsidiaries and
30 international traders. Our industrial customers value us as a
reliable development partner and producer with high application
knowledge and superior customer service.

Meet with us at INTER SOLAR EUROPE 2012 in hall C2 / booth 174
from 13th to 15th of June 2012 at New Exhibition Centre, Munich,
Germany

Contact:
Inter Control
Schafhofstraße 30
D-90411 Nuremberg, Germany
www.intercontrol.de

Further information:
Contact Joachim Klawonn
Phone +49 (0)911 9522-817
E-Mail joachim.klawonn@intercontrol.de