Energy output/consumption at night

Hi Paul,

A few more questions:)

1. Is there a way to specify in an LK script that I want the system sizing to be on the "specify modules and inverters" setting rather than "specify desired array size" or do I just need to make that adjustment in a project and then set it to be the active case.


2. I printed "year1_hourly_system_to_load" which gave values of energy produced (or consumed) at each hour for the first year. At night time, the production is a nonzero value, for this case it was -3.64. I was wondering where the consumption is coming from. I don't think that the inverter running at night accounts for the entirety of this, and was wondering if the module also caused this? Or something else I'm missing?

Edit:
Today I printed "year1_hourly_system_to_load" and it has 0s for nighttime but it doesn't add up to the same amount as the annual energy and I don't understand why they wouldn't always be the same.

Thanks for always being so prompt and thorough. It's really appreciated.

Hello,
1. The variable name for the system sizing mode is , where a value of 0 is equivalent to "Specify desired array size" and 1 is equivalent to "Specify modules and inverters." Note that in LK, SAM will not run the sizing checks that it does in the user interface, so you'll want to be careful to verify that the values of , , and are correct. I just uploaded a sample script to the LK Cookbook that demonstrates how to work with those two options in LK.
2. The reason "electricity system to load" is not the same as "power generated by system" is that the system may generate more or less power than is required by the load. The power generated by the system may either go to the load, or go to the grid, or both. The sum of the totals of "electricity to grid" and "electricity from system to load" should equal "power generated by system." Negative values for "power generated by system" are caused by the inverter's nighttime consumption, and should be equal to the product of "Power consumption at night" on the Inverter page and the number of inverters on the System Design page.
Best regards,

Paul.

THANKS!