Sloped Terrain inputs for backtracking algorithm, shadeFraction #648

mjprilliman · 2021-11-09T23:47:27Z

-new cross_axis_slope function to calculate cross axis slope from terrain tilt and azimuth
-PVsamv1 allows for terrain effects on shadeFraction for non-zero terrain inputs
-Additional inputs to shadeFraction function, given 0 values for flat terrain for all non-pvsamv1 instances
-Added test for non-zero terrain inputs
-Reference: https://www.nrel.gov/docs/fy20osti/76626.pdf

function; updated tests and function calls

terrain option only available for single axis tracking

backtracking functions

janinefreeman

Other than the one comment about changing the input to irradproc, looks good to me!

janinefreeman · 2021-11-11T18:01:38Z

ssc/cmod_irradproc.cpp

        { SSC_INPUT,        SSC_NUMBER,      "rotlim",                     "Rotational limit on tracker",    "deg",    "",                      "Irradiance Processor",      "?=45",                    "MIN=0,MAX=90",                             "" },
        { SSC_INPUT,        SSC_NUMBER,      "backtrack",                  "Enable backtracking",            "0/1",    "",                      "Irradiance Processor",      "?=0",                    "BOOLEAN",                                   "" },
        { SSC_INPUT,        SSC_NUMBER,      "gcr",                        "Ground coverage ratio",          "0..1",   "",                      "Irradiance Processor",      "backtrack=1",              "MIN=0,MAX=1",                             "" },
+        { SSC_INPUT,        SSC_NUMBER,      "cross_axis_slope",                        "Cross axis slope",          "deg",   "",                      "Irradiance Processor",      "backtrack=1",              "MIN=0,MAX=1",                             "" },


I think we don't want this input to be required, but rather to be set by default to zero (?=0).

reference to "cross_axis_slope" (unused)

kandersolar

Hi folks, thanks again for finishing this up! Here are some comments, maybe too little too late at this point.

@mikofski fyi

kandersolar · 2021-11-12T18:03:08Z

shared/lib_irradproc.cpp

            else if (en_backtrack) {
                // TODO: add cross-axis slope angle parameter
-                double backtracking_rotation = backtrack(truetracking_rotation * 180 / M_PI, gcr);
+                double axis_slope = cross_axis_slope(slope_tilt, azm, slope_azm);


axis_slope has potential to be misinterpreted as axis tilt if not reading carefully. Maybe rename the function to calc_cross_axis_slope and then the variable can be named cross_axis_slope? Just an idea :)

Also, I think the comment in the line above can be removed now. Similar comments appear in this file in a couple other places.

kandersolar · 2021-11-12T18:11:35Z

shared/lib_irradproc.h

 * \return fraction shaded (0-1) if system is shaded (0 for unshaded)
 */
-double shadeFraction1x(double solar_azimuth, double solar_zenith, double axis_tilt, double axis_azimuth, double gcr, double rotation);
+double shadeFraction1x(double solar_azimuth, double solar_zenith, double axis_tilt, double axis_azimuth, double gcr, double rotation, double slope_tilt, double slope_azimuth);


Do these new parameters need to be listed in the docs comment above?

kandersolar · 2021-11-12T18:12:10Z

shared/lib_irradproc.h

 * \return updated rotation angle in degrees after backtracking
 */
-double backtrack(double truetracking_rotation, double gcr);
+double backtrack(double truetracking_rotation, double gcr, double axis_slope);


Same comment re: listing new param in the doc comment

kandersolar · 2021-11-12T18:14:38Z

ssc/cmod_pvsamv1.cpp

        {SSC_INPUT, SSC_NUMBER,   "subarray2_rotlim",                     "Sub-array 2 Tracker rotation limit",                  "deg",    "",                                                                                                                                                                                      "System Design",                                         "?=45",                               "MIN=0,MAX=85",        "" },
        {SSC_INPUT, SSC_NUMBER,   "subarray2_shade_mode",                 "Sub-array 2 Shading mode (fixed tilt or 1x tracking)","0/1/2",  "0=none,1=standard(non-linear),2=thin film(linear)",                                                                                                                                     "Shading",                                               "subarray2_enable=1",                 "INTEGER,MIN=0,MAX=2", "" },
        {SSC_INPUT, SSC_NUMBER,   "subarray2_gcr",                        "Sub-array 2 Ground coverage ratio",                   "0..1",   "",                                                                                                                                                                                      "System Design",                                         "?=0.3",                              "MIN=0.01,MAX=0.99",   "" },
+        {SSC_INPUT, SSC_NUMBER,   "subarray2_slope_tilt",           "Sub-array 1 Cross axis slope",                        "deg",   "",                                                                                                                                                                                      "System Design",                                         "?=0.0",                                                "",   "" },


This is for subarray2 but says "Sub-array 1 Cross axis slope". Same for subarrays 3 and 4

kandersolar · 2021-11-12T18:16:51Z

ssc/cmod_pvsamv1.cpp

        {SSC_INPUT, SSC_NUMBER,   "subarray1_shade_mode",                 "Sub-array 1 shading mode (fixed tilt or 1x tracking)","0/1/2",  "0=none,1=standard(non-linear),2=thin film(linear)",                                                                                                                                     "Shading",                                               "*",                                  "INTEGER,MIN=0,MAX=2", "" },
        {SSC_INPUT, SSC_NUMBER,   "subarray1_gcr",                        "Sub-array 1 Ground coverage ratio",                   "0..1",   "",                                                                                                                                                                                      "System Design",                                         "?=0.3",                              "MIN=0.01,MAX=0.99",   "" },
+        {SSC_INPUT, SSC_NUMBER,   "subarray1_slope_tilt",           "Sub-array 1 Cross axis slope",                        "deg",   "",                                                                                                                                                                                      "System Design",                                         "?=0.0",                                                "",   "" },
+        {SSC_INPUT, SSC_NUMBER,   "subarray1_slope_azm",           "Sub-array 1 Cross axis slope",                        "deg",   "",                                                                                                                                                                                      "System Design",                                         "?=0.0",                                                "",   "" },


I think there are two issues in the description here -- first, Sub-array 1 Cross axis slope is used for both slope_tilt and slope_azm inputs. Second, I don't think either of these is actually a cross-axis slope :)

And same for subarrays 2-4

mjprilliman · 2021-11-12T18:42:24Z

Thanks Kevin! I'll add your edits in a separate commit as that will help eliminate a lot of confusion for anyone looking at this code in ssc. @janinefreeman these are all just text changes so I think I'll just commit them to develop

Revise description of load data time convention. Remove O&M cost content from Installation Costs topics. Add ETES topics and fix broken help links. Fix typo on battery storage FOM "BTM" insteasd of "FOM" Wind resource files can now be .csv in addition to .srw Revise capacity factor descriptions for PV and Battery storage configs, #905 Wave resource instructions for converting from time series to JPD, #892 Revise PV land area calculations to account for GCR and tilt angle, #928 Add pvlib column headings to SAM CSV format description, NREL/ssc#754 Revised Operating Cost input pages Check for "annual energy" vs new "electricity to grid". Change "battery autonomy" to "autonomy". Revise power tower heliostat field to better explain how check box vs button works. Add note for degradation by year that Year 1 value should be zero, #755 Remove debt from payback period description. Also remove detailed cash flow descriptions and replace with mention of send-to-Excel with equations and spreadsheets on website. See Amir Nashed email 1/19/21 and https://sam.nrel.gov/forum/forum-general/1052 Revise Electricity Purchases page to be specific for FOM projects New LCOS metrics: #529 Electricity rates revisions from Brian. Reporting of electricity bill in time series results, see NREL/ssc#652 New parametrics features Parametrics description of how to work with SchedNumeric variables like PPA price. See Brian email 7/21/2021 Update Heliostat Field per #717 New PV slope inputs on System Design page. See #742, NREL/ssc#648 New "Limit debt fraction" Input on Financial Parameters page for PPA models New ETES model. Fix outdated description of NSRDB in Location and Resource topic UDPC updates from Ty, see Revisions 2021 folder. Also post new PDF version of Ty and Matt's description under "CSP Power Cycle Models" on SAM website https://sam.nrel.gov/concentrating-solar-power/csp-publications.html, https://sam.nrel.gov/images/web_page_files/Neises-DRAFT-user-defined-power-cycle-v3-2018.pdf Fix excess generation descriptions in help: https://sam.nrel.gov/forum/forum-general/3485. Also maybe change "Excess generation" to "Excess generation for net metering" or similar. Note for URDB download that demand ratchet data in URDB is unreliable, so check with data sheet. Demand charges with ratcheting lookback months. See Revision Notes mirletz-RE Adding billing demand lookback to SAM.msg, see [[F:\OneDrive\SAM\Utility Rates\Demand Ratchets\Initial Tests May 2021]] Update pv smoothing per Steve's email 12/9/2021 "pv smoothing question" Improve description of FOM automated dispatch. See https://sam.nrel.gov/forum/forum-general/3681 Revise electricity rates page Consolidate weekday/weekend schedule descriptions. SWH remove old hot water draw import instructions. Revise electricity purchases PPA price option not available with Specify IRR target, and purchases treated as tax-deductible operating expense. Move electricity purchases page to from Battery section to Electricity Rates and Load section Edit Lifetime Data add note about pasting data from Excel: Thousands comma separator causes paste not to work correctly, e.g, 1,000 is pasted as 1.

mjprilliman added 8 commits October 18, 2021 17:30

Added cross axis slope input to backtracking algorithm, incidence

352c10a

function; updated tests and function calls

Merge branch 'develop' into cross_axis_slope

3f48ab2

Added slope tilt and azimuth variables to calculate cross axis slope

9138c50

Merge branch 'develop' into cross_axis_slope

971e43a

Updated shadeFraction1x function with terrain inputs, made sloped

368ce1c

terrain option only available for single axis tracking

Merge branch 'develop' into cross_axis_slope

efcd11a

Added tests for non-zero ground terrain inputs to test shadefraction and

a3c46eb

backtracking functions

Merge branch 'develop' into cross_axis_slope

90b6b47

mjprilliman added the pv photovoltaic, pvsam, pvwatts label Nov 9, 2021

mjprilliman added this to the SAM Fall 2021 Release milestone Nov 9, 2021

mjprilliman requested review from dguittet and janinefreeman November 9, 2021 23:47

mjprilliman self-assigned this Nov 9, 2021

janinefreeman removed the request for review from dguittet November 11, 2021 17:55

janinefreeman approved these changes Nov 11, 2021

View reviewed changes

mjprilliman added 3 commits November 11, 2021 20:58

Merge branch 'develop' into cross_axis_slope

4c5e6f7

Cleaned up var_table terrain angle inputs (default to 0), removed

042bb97

reference to "cross_axis_slope" (unused)

Merge branch 'develop' into cross_axis_slope

3120a3f

mjprilliman merged commit 44f15ca into develop Nov 12, 2021

mjprilliman deleted the cross_axis_slope branch November 12, 2021 18:09

kandersolar reviewed Nov 12, 2021

View reviewed changes

cpaulgilman mentioned this pull request Dec 1, 2021

Help revisions for SAM 2021.12.02 initial release NREL/SAM#832

Merged

cpaulgilman mentioned this pull request Feb 17, 2022

Help revisions for SAM 2020.12.02. r1 NREL/SAM#938

Merged

Provide feedback

Saved searches

Use saved searches to filter your results more quickly

Uh oh!

Sloped Terrain inputs for backtracking algorithm, shadeFraction #648

Sloped Terrain inputs for backtracking algorithm, shadeFraction #648

Uh oh!

mjprilliman commented Nov 9, 2021

Uh oh!

janinefreeman left a comment

Uh oh!

janinefreeman Nov 11, 2021

Uh oh!

kandersolar left a comment

Uh oh!

kandersolar Nov 12, 2021

Uh oh!

kandersolar Nov 12, 2021

Uh oh!

kandersolar Nov 12, 2021

Uh oh!

kandersolar Nov 12, 2021

Uh oh!

kandersolar Nov 12, 2021

Uh oh!

mjprilliman commented Nov 12, 2021

Uh oh!

Reviewers

Assignees

Labels

Projects

Milestone

Development

Uh oh!

4 participants

Sloped Terrain inputs for backtracking algorithm, shadeFraction #648

Sloped Terrain inputs for backtracking algorithm, shadeFraction #648

Uh oh!

Conversation

mjprilliman commented Nov 9, 2021

Uh oh!

janinefreeman left a comment

Choose a reason for hiding this comment

Uh oh!

janinefreeman Nov 11, 2021

Choose a reason for hiding this comment

Uh oh!

kandersolar left a comment

Choose a reason for hiding this comment

Uh oh!

kandersolar Nov 12, 2021

Choose a reason for hiding this comment

Uh oh!

kandersolar Nov 12, 2021

Choose a reason for hiding this comment

Uh oh!

kandersolar Nov 12, 2021

Choose a reason for hiding this comment

Uh oh!

kandersolar Nov 12, 2021

Choose a reason for hiding this comment

Uh oh!

kandersolar Nov 12, 2021

Choose a reason for hiding this comment

Uh oh!

mjprilliman commented Nov 12, 2021

Uh oh!

Reviewers

Assignees

Labels

Projects

Milestone

Development

Uh oh!

4 participants