An analysis of the performance and development of a model to estimate the output for a Parabola Trough Concentrator based solar thermal system
Student name: Mr Vineeth S
Guide: Mr N S Prasad
Year of completion: 2014
Host Organisation: THERMAX
Supervisor (Host Organisation): Mr Kiran Deshpande
Abstract: Parabolic Trough Concentrators (PTC) are the most advanced solar thermal technologies.
Solar thermal energy is a potential source of renewable energy for industrial process heating
and parabolic trough collectors are the most common technology used. System designers
have to optimally size the solar field so as to provide techno-economically viable solution for
industrial heat. Therefore it is important to have a model to estimate the annual output from a
PTC system. An excel based model was developed to estimate the output from the parabola
trough system mounted in any axis or slope. Analysis was done to determine the orientation
with maximum output, different optical loss. It was found that the North South orientation of
collector gives the maximum annual output when it is mounted horizontal to surface. The
output further increases and becomes maximum when the axis tilted at an angle equal to the
latitude of the location.
The output of PTC is sensitive to tracking. If there is an error in axis orientation from
design value, then tracking will not be optimum, hence the output is impacted. A model was
also developed to find out the loss due to error in orientation. It was found the East West
orientation was more sensitive to error.
Literature study was done to understand the equations and formulas for the optical loss.
Field experiments were carried to determine the receiver thermal loss correlation. A
commercial plant using the PTC system for process heating was chosen for a case study. The
study was done for Thermax PTC collector.
The model does not consider the Incident Angle Modifier (IAM). As the angle of
incidence increases, IAM will have an impact on the optical efficiency. The current model
can be improved by accommodating IAM in the future.
Keywords: Parabola trough concentrator, Optical Losses, Model, Efficiency
