more Heat loss at design (receivers) has more energy output?

Dear sir
By duplicating two typical cases and only changing the value of the heat loss at design (receivers)
The strange result is that the case with more heat loss has more Q absorbed, Q dumped,
Q field output and more net annual energy.
Is this an error or maybe I have misunderstood something.
(These cases are done by SCHOTT 2008 and siemens tube, and both have the same errors.)

I appreciate your help
Thank you
Regards
Zeyad Yasser

Dear Zeyad Yasser,

I assume you are running either the physical trough model or the empirical trough model. In either case, on the Solar Field page under Field Layout, if you choose Option 1 Solar Multiple, SAM adjusts the solar field area to account for the heat loss at design value. That may explain why Q absorbed increased when when you increased the heat loss at design value -- SAM increased the field area to ensure that under design conditions, the solar field can drive the power block at its nameplate capacity.

Best regards,
Paul.