Skip navigation to main content.
NREL - National Renewable Energy Laboratory
About NRELEnergy AnalysisScience and TechnologyTechnology TransferTechnology DeploymentEnergy Systems Integration

Parabolic Trough Technology Models and Software Tools

Here you'll find information about models and software tools used to analyze parabolic trough power plant technology. They include:

Annual Simulation Software

Because solar power plants rely on an intermittent fuel supply—the sun—it is necessary to model the plant's performance on an hourly (or finer resolution) basis to understand and predict its annual performance.

A number of performance and economics models are available for evaluating parabolic trough solar technologies. Industry also has developed a number of proprietary models for evaluating parabolic trough plants.

Solar Advisor Model

NREL, partnering with the U.S. Department of Energy's Solar Energy Technologies Program and Sandia National Laboratories, developed the Solar Advisor Model (SAM). This model supports the implementation of projects within the program, and also supports industry calculations of the cost of energy.

The Solar Advisor Model—a comprehensive solar technology systems analysis model—allows users to investigate the impact of variations in physical, cost, and financial parameters to better understand their impact on key figures of merit. Figures of merit related to the cost and performance of these systems include, but are not limited to, the following:

  • System output (hourly, monthly, and annual)
  • Peak and annual system efficiency
  • Levelized cost of electricity
  • Net present value
  • System capital costs
  • System operating and maintenance (O&M) costs.

For more information, see the following NREL documents related to SAM: "Sensitivity of Concentrating Solar Power Trough Performance, Cost and Financing with Solar Advisor Model" (PDF 909 KB) and "Modeling Photovoltaic and Concentrating Solar Power Trough Performance, Cost, and Financing with the Solar Advisor Model" (PDF 373 KB). Download Adobe Reader.

You can download the current version of SAM, which contains a parabolic trough system. A version of SAM for dish/Stirling systems will be available later this year. Power tower and linear Fresnel systems will be available in the future, as well.


The University of Wisconsin developed TRNSYS to analyze renewable energy systems, including parabolic trough solar technology. Also, several recent efforts have developed TRNSYS models for modeling specific parabolic trough technologies:

For more information, demos, and downloads for a transient systems simulation program, visit the University of Wisconsin's TRNSYS Web site.

In addition, SolarPACES maintains a special library of TRNSYS components for modeling parabolic trough and other concentrating solar power systems.

Back to Top

Other Software Analysis Tools

The following tools may be valuable in evaluating parabolic trough systems and components.


NREL developed SolTrace—a ray tracing model—to model solar power optical systems and analyze their performance. The model can be used to develop new, complex solar optical designs that previously couldn't be modeled.

SolTrace can model parabolic trough concentrators as well as dishes, towers or other unique geometries (linear power towers, solar furnaces, etc.). In addition, it can model any number of stages containing any number of different elements. It features an extensive variety of available shapes and contours. The software rapidly displays and saves data as scatter plots, flux maps, and performance graphs. It also can model optical geometries as a series of stages composed of optical elements that possess attributes including shape, contour, and optical quality.

Download SolTrace.

Receiver Model

NREL developed a one-dimensional model—called the Forristal model—based on an approach developed by Sandia National Laboratories to predict the thermal performance of parabolic trough receivers.

Researchers developed the model to assess the trade-offs of different designs and properties of materials used in the receiver for a range of operating and ambient conditions. The model can also account for different levels of vacuum and gas compositions in the annulus.

Figure 1 shows the modeled thermal losses of a new receiver with good vacuum, and receivers with different pressures of air, hydrogen, and helium in the annulus space.

A chart showing the thermal losses from a parabolic trough receiver with various gasses or levels of vacuum between the glass envelop and the steel tube for a receiver at 350C. Thermal losses for a receiver that has lost vacuum and has air in the annulus double. If helium permeates into the receiver up to the atmospheric partial pressure, thermal losses increase by about one third. If hydrogen permeates into the annulus, the thermal losses may increase by a factor of four.

Figure 1. Thermal losses from a parabolic trough receiver

For more information on the Forristal receiver model, read NREL's technical report, Heat Transfer Analysis and Modeling of a Parabolic Trough Solar Receiver Implemented in Engineering Equation Solver (PDF 1.9 MB). Download Adobe Reader.


DView, for data viewer, is a data visualization program used for viewing hourly time-series data. It allows plots of hourly data or summarizes the data into daily or monthly totals as well as calculating various statistics.

DView gives the user the ability to select which data to view and over which time interval. It uses DMap (data map) to display time-series data with the day of the year on the x-axis and time of day on the y-axis. Using this format, it's also possible to make sense of a year or more of time-series data in a single graph, and identify both daily and seasonal patterns.

Figure 2 shows the direct normal solar radiation in Boulder, Colorado, from the TMY2 data set. It is possible to see that the days are longer in the summer than the winter. The most intense direct radiation values tend to occur in the spring and fall. And summer afternoons tend to be cloudy.

A computer screen shot image of the DView display showing the time-series fluctuations in radiation.

Figure 2. DView display of direct normal solar radiation in Boulder, Colorado

Mistaya Engineering developed DView for NREL. For more information or to download DView at no cost, visit the Mistaya Engineering Web site.

Job and Economic Development Impact (JEDI)

NREL's Strategic Energy Analysis and Applications Center developed several Job and Economic Development Impact (JEDI) models that are easy-to-use, spreadsheet-based tools. The JEDI models estimate the economic impacts of constructing and operating power generation plants at the state level.

First developed in 2002 to model wind energy development impacts, JEDI has been expanded to offer more technologies, including concentrating solar power. Running in Excel, users download the appropriate JEDI model and enter basic information about a project, including: the state, location, year of construction, and facility size. Using these data, the model then estimates the following:

  • Project costs (i.e., specific expenditures)
  • Economic impacts from
    • Jobs
    • Earnings (i.e., wages and salary)
    • Output (i.e., value of production).

More information on the models, how to download them, and their applications are available on the JEDI Web page.

Back to Top

More Information

See our publications on parabolic trough models and software tools.

Also learn more about NREL's modeling and analysis capabilities for concentrating solar power technologies.

Back to Top