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Engineering and Techno-Economic Assessment

The concentrating solar power (CSP) program at the National Renewable Energy Laboratory (NREL) measures and models the solar resource, develops and uses computer models for engineering design and modeling of system performance and technology deployment, and investigates the environmental benefits and impacts of utility-scale solar power.

Learn more about the capabilities discussed below by contacting the CSP Research Staff.

System Advisor Model

The System Advisor Model (SAM) is a performance and financial model that provides performance predictions and cost-of-energy estimates for grid-connected power projects, based on specified installation and operating costs and system design parameters. NREL, partnering with the U.S. Department of Energy's Solar Energy Technologies Office and Sandia National Laboratories, developed SAM. This model supports the implementation of projects within the program, and also supports industry calculations of the cost of energy.

SAM window showing a power project's parameterized storage (LCOE), parameterized storage contour (LCOE), stacked costs (base case), and monthly output (base case). Image by NREL.

SAM is a comprehensive solar technology systems analysis model that 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 costs.


SolarPILOT allows engineers to design and optimize complex solar field configurations for power tower systems.

SolarPILOT, or the Solar Power tower Integrated Layout and Optimization Tool, addresses the performance and layout requirements for power tower systems. It integrates the rapid layout and optimization capability of the analytical DELSOL3 program with the accuracy and precision of SolTrace ray tracing.


This NREL tool for optical modeling of CSP applications allows users to create geometric models for all types of CSP technology options (dish, tower, trough) to design and analyze optical performance of these systems.

SolTrace uses a Monte Carlo ray trace method, here being applied to a linear Fresnel CSP configuration.

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 could not be modeled.

SolTrace can model parabolic trough concentrators as well as dishes, towers, or other unique geometries (linear power towers, solar furnaces). 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.


The Resource Information and Forecasting group provides the necessary solar data, satellite imagery, and geographical information systems to help analysts and stakeholders better understand the feasibility of locating a CSP plant in a particular area.

Grid Optimization

Dispatch of California Independent System Operator (CAISO) generator fleet for two days in spring, summer, and winter in a 33% renewable portfolio standard case. The black line shows total load.

Photovoltaic and wind technologies are considered variable-generation sources of electricity because they depend on the sun shining and the wind blowing. Therefore, if connected to the power grid, these technologies contribute electricity into the grid intermittently. CSP plants can even out the ebbs and flows of such inputs by ramping up output from thermal energy storage. In our grid-optimization research, NREL analysts use utility production cost models such as PLEXOS to determine the impact on the power grid of renewable energy systems—especially the variable generation from photovoltaic and wind technologies.


Regional Energy Deployment System (ReEDS) is a software model used to determine energy and environmental impacts. Learn more[BROKEN LINK].

ReEDS output from a scenario that shows increasing cumulative installed capacity from renewable energy technologies.


Jobs and Economic Development Impact (JEDI) is a user-friendly model that estimates the economic impacts of constructing and operating power generation and biofuel plants at the local and state levels.

Developed by NREL's Strategic Energy Analysis and Applications Center, JEDI's models are easy-to-use, spreadsheet-based tools.

First developed in 2002 to model wind energy development impacts, JEDI has been expanded to offer more technologies, including CSP. 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: (1) Project costs (i.e., specific expenditures), and (2) economic impacts from jobs, earnings (i.e., wages and salary), and output (i.e., value of production).

More information on the models, how to download them, and their applications are available on the JEDI[BROKEN LINK] web page.