Electricity Purchases Load Rate Data issue

Hello,

I am presently engaged in a hybrid solar-plus-storage project and am interested in selling my energy at a PPA price while also purchasing energy at retail electricity rates. To input my own data, I saved the base CSV file and opened it in Excel. I only made changes to the sell rate and buy rate using my data file, also in CSV format. However, SAM failed to load the modified retail rate data file when I attempted to do so. Is there something I may have forget to do?

Best regards,
Benjamin

Hi Benjamin,

If I understand correctly, you used the Save rate to file button at the top of the Electricity Purchases page to save the rate data to a .csv file, used Excel to modify the .csv file to change the buy and sell rates, and then used the Load rate from file button on the Electricity Purchases page to load the modified rate data into SAM.

This should work, unless you changed the structure of the data in the .csv file. Sometimes Excel automatically changes the format of numbers, which could cause SAM to not recognize the file.

Please attach a copy of a .csv file that demonstrates the problem if you would like me to help troubleshoot.

Best regards,
Paul.

Hi Paul, 

Thank you for your fast answer, you did understand my problem. In the attached files you can find two csv files (one of the basic retail electricity price I firstly saved from SAM   , one of the retail electricity price with my modifications   . As I opened it in Excel, I attached a screen of the modification I made in Excel   and finally the error I have in SAM when I'm trying to load the modified csv   . 

Best regards, 

Benjamin LEMATTRE. 
 

Hi Benjamin,

There are a couple of problems with your modified file:

1. The first row has the text "Column1;Column2;Column3." It should have the data for the 'ur_ec_tou_mat' variable.
2. The columns are separated by semicolons instead of commas.

Attached is a version of your file that should work. You'll need to verify that the data is correct.

I used a good text editor to compare the original file with yours to identify these problems.

If you use a spreadsheet program to edit the file, please make sure to use commas as the column delimiter when you save the file.

Best regards,
Paul.

Hi Paul, 

Thank you for your answer, this new file worked pretty well. I'll use a text editor as well to not have problems with columns ! 
Last question, how is SAM considering the csv file ? For instance if my string with market data have the length of 8760, do SAM consider automatically that it is hourly variables for 1 year ? Or do I need to specify it somewhere ? 

If I want to do a 20 years simulation with electricity market data, do I need to put a string of 8760*20 long or is the first string of 8760 data enough and sam consider the electricity price to be the same each year ? 

I don't know if I'm clear enough in these questions, I'm sorry if I'm not. 

Best regards, 

Benjamin. 

Hi Benjamin,

SAM's electricity bill calculator assumes that the first time step in the simulation is in the first hour of Monday, January 1. When you provide time series electricity rate data as input, SAM automatically considers it to be hourly data if has 8,760 rows, 15-minute data if it has 35,040 rows, etc. You do not need to specify time stamps or time resolution in the .csv file.

SAM only accepts electricity rate data for Year 1. If you are providing hourly time series data, it should contain 8760 values.

You can use the electricity bill escalation rate to adjust the rates in future years.

Best regards,
Paul.