IS it possible that the receiver that has more heat loss produce more power?

by simulating two identical cases (duplicating) having the same area and the same number of loops.
the case that contain a reliever with MORE HEAT LOSS produce more Q FIELD OUTPUT and MORE NET ANNUAL ENERGY.

although the two receivers used are identical but the only difference is the heat loss.

Zeyad,

This is a relatively common misunderstanding of how the Physical Trough model uses the receiver "estimated heat loss" values. The Physical Trough model uses a detailed, iterative performance model for receiver heat loss (see Forristall, 2003), and because of this, we aren't able to directly implement the model in the SAM interface. As a result, the interface does not have a good way of determining the receiver heat loss and total solar field efficiency when it sizes the solar field. We chose to work around this issue by providing an input for estimated receiver heat loss, and SAM uses this value ONLY to determine the estimated design point solar field efficiency for sizing calculations. This value is NOT used during annual performance calculations.

In your case, when you specified the solar field aperture area and changed the estimated heat loss, SAM recalculated the solar multiple to account for the poorer solar field efficiency. The new solar multiple impacted the sizing of the thermal energy storage heat exchanger, and the resulting system produces a slightly different annual output on the order of ~0.15%, which is well within the precision uncertainty of the model.

To alter receiver performance, you might instead consider changing the absorber emittance values, the absorptivity, or other physical parameters that affect the receiver performance.

Mike Wagner
NREL