Switching from Earlier Versions

Solar Advisor Model 2009 maintains the same capabilities as the version 3.0, but adds several new capabilities, has a new look and feel, and runs more efficiently.

One conceptual difference between the two versions is that in SAM 2009, the input variables on the input pages are separate from the simulation configurations. In SAM 3.0, you configure parametric analyses and set up linked spreadsheets directly from the input pages. In SAM 2009, all simulation configurations are handled in one place: The Configure Simulations page. The input pages only contain input variables, and each variable has a single "base case" value, or in the case of variables with annual schedules, a series of annual base case values.

Contents

►	New Look and Feel describes some of the changes in the user interface's appearance and organization.

►	Working with Files from SAM 3.0 explains how to import SCIF files from SAM 3.0 into SAM 2009.

►	Results Graphs and Tables explains some of the differences between the two versions' results pages.

►	General Model Improvements describes some changes to the cost, financing, and performance models that will cause results to differ between the two models.

►	Improvements to Parametric Analysis explains how the parametric analysis feature has changed in the new version.

►	Improvements to Linked Spreadsheet Functionality explains the differences between SAM 3.0 linked spreadsheets and SAM 2009 Excel Exchange.

►	Weather Data Enhancements explains SAM 2009 weather data handling improvements.

New Look and Feel

SAM 2009 uses a redesigned user interface that preserves the general layout of SAM 3.0 and earlier versions, but runs more efficiently. In SAM 2009 you still aaccess input pages using the navigation menu just like in SAM 3.0, but the menu has been slightly reorganized.

•	The navigation menu buttons in SAM 3.0 have been removed. In SAM 2009, you can click an item on the menu to open the input page.

•	The Program page in SAM 3.0 where you define the project's technology and market has been replaced by the Technology and Market window.

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Right-clicking variables no longer displays the Input Type window. The Parametric Analysis and Excel Exchange (linked spreadsheets) features that were available by right-clicking variables in SAM 3.0 are now handled as simulation configuration options. Variables that can be entered as Annual Schedules display a button next to the label that you can click to edit the annual schedule.

•	A new Annual Performance page displays annual degradation and availability variables, which are used consistently across all technologies to facilitate comparison.

•	The Costs page in SAM 3.0 has been replaced with the system costs page for each technology, and its position on the navigation menu has been moved.

Working with Files from SAM 3.0

You can open a project file created in SAM 3.0 by saving it as a SCIF file and opening it in SAM 2009.

A SCIF file contains a complete set of input values for one or more cases in a project file. Note that SAM 2009 cannot save files in the SCIF format. Because the new .zsam project file format used by SAM 2009 is much more compact than the SAM 3.0's .sam format, the SCIF format has been deprecated in the new version.

Note. SAM 2009 does not convert parametric variables or variables linked to spreadsheets from SCIF files. If your SAM 3.0 project files includes those features, you will need to set up the parametric analysis or Excel exchange in SAM 2009. See Parametric Analysis and Excel Exchange for details.

To convert a file from SAM 3.0 to SAM 2009:

1.	Start both SAM 2009 and SAM 3.0. The two versions can run simultaneously on your computer without interfering with each other.

2.	In SAM 3.0, on the File menu, click Save As SCIF.

3.	In the Save As SCIF window, choose the cases from the file that you want to include in the SCIF file.

4.	Click the Browse button to open the Save As window.

5.	Navigate to the location on your computer where you want to save the file.

6.	In File name, type the name of the file, including the .scif extension. For example, type the complete name "MySolarProject.scif"

7.	Click Save. It may take several seconds to convert and save the file.

8.	In SAM 2009, on the File menu, click Open SCIF File.

9.	In the Choose a SCIF File window, browse to the folder containing the SCIF file.

10.	In the Save Converted File As window, choose a location to save the SAM 2009 project file. You can save the file to any location on your computer or a network.

11.	When SAM 2009 finishes converting the project to the .zsam format, click Yes to open the file.

If the SCIF file uses a weather file that is not included in the SAM 2009 standard library, before going to the next step, you will need to add the file to the library of weather file locations on the Climate page. See Managing Weather Files for details.

12.	Click Run all simulations to generate a set of SAM 2009 results. See Getting Started for help getting around the new user interface.

SS_Results-RunAllSimulations

Results Graphs and Tables

SAM 2009 displays tables and graphs of results on the Results page, whose appearance has significantly changed from SAM 3.0. See Reviewing Results for help getting started with the Results page, and see Results Page Reference for more details.

Some key differences include:

•	The run and results buttons still appear on at the bottom of the navigation menu, but their appearance has changed. See Running Simulations and Reviewing Results for details.

SAM 3.0	SAM 2009

•	The Metrics table and sliders appear under the navigation menu instead of on the Results page, freeing up space for graphs on the Results page.

SAM 3.0	SAM 2009

•	Choose graphs to display from the Graphing tab at the bottom of the Results page instead of from the list at the top.

SAM 3.0	SAM 2009

General Model Improvements

SAM 2009 uses the same cost, financing, and performance models to simulate systems as SAM 3.0, with some improvements that may cause results from the two versions to differ:

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The photovoltaic single-point efficiency models for flat-plate and concentrating photovoltaic modules have been replaced by the simple efficiency models, which allow you to enter efficiency values for a range of standard incident radiation levels, and to define the reference radiation used to calculate the module's rated power.

•	For CSP parabolic trough and power tower systems the storage dispatch logic has been improved.

•	For CSP power tower systems, the input variables have been reorganized, and duplication of variables in the input pages and optimization wizard removed.

•	For CSP trough and power tower systems, the backup boiler fuel cost is tracked and included in the cash flow and other economic metrics displayed on the Results page.

•	The photovoltaic technology option includes a new implementation of NREL's PVWatts model, which includes preliminary test versions of battery storage and electric load models.

•	Input variable libraries use the same format across all technologies and input variable types. The library format is text-based, and the library editor allows for data to be added to libraries without modifying the standard libraries. See Working with Libraries for details.

•	For projects with utility financing, the financial variable optimization no longer requires excel.

Improvements to Parametric Analysis

SAM 2009's Parametric Analysis simulation configuration option makes setting up and managing parametric analyses much simpler than in SAM 3.0 and earlier versions:

•	Parametric variables are defined on the Parametric Analysis Configuration page instead of by right-clicking variable names on the input pages.

•	The new optimization option uses a search algorithm to find optimal values of variables. providing an automated alternative to the manual method using parametric analyses and graphs.

•	The new Sensitivity Analysis option allows you to define ranges of variable values using upper and lower limits so that you can perform sensitivity studies without specifying individual values.

•	Parametric simulation configurations can be enabled or disabled for each model run, allowing you to set up as many parametric analyses as you like and choose which ones to include in a simulation run to save time.

Improvements to Linked Spreadsheet Functionality

The Excel Exchange simulation option allows you to manage data exchange between SAM 2009 input variables and Excel worksheet cells. The new implementation provides several advantages over SAM 3.0:

•	The Excel Exchange configuration page allows you to manage data sharing with Excel in a central location.

•	Excel can run simultaneously with SAM without causing any interference. You can edit the Excel workbook while SAM is running. SAM exchanges values with the saved copy of the workbook.

•	Excel workbooks can be stored in any location on your computer. They no longer have to be stored in the Worksheets folder.

•	User-defined variables (UDVs) from SAM 3.0 have been replaced by user variables.

Weather Data Enhancements

By default, SAM 2009 project files do not include data from weather files to minimize file size and improve the model's efficiency. During simulations, SAM 2009 reads data from the weather files, rather than from a database stored within the project file. The new weather file location library helps you manage weather file locations.

•	SAM 2009 reads the new TMY3 weather format, as well as the TMY2 and EPW formats recognized by SAM 3.0.

•	An Excel tool is available for converting your own weather data to TMY3 format. Contact solar.advisor.support@nrel.gov for a copy of the tool.

•	If you are sharing a project file with another person and want to include weather data in the file rather than sharing the weather file separately, you can copy the weather data to the project.

•	For SAM 3.0 or earlier projects with parametric variables or variables linked to Excel, you have to configure the simulations, see Configuring Simulations.