Thermal Capacity Estimation and 3 more question..

Hi all,

I'm working on a dissertation but I could not figure out some questions.
Hope you can help me..

Firstly, I would like to ask "what is the criteria to determine the thermal capacity of solar tower systems?"
Secondly, the programme ask us to enter a solar multiple value. How can we know what is the optimum solar multiple for our system.
Third question is, How does the programme determine the heliostat total reflective area?
Final one is, The hourly DNI value is W/m2 but the solar flux is MW/m2. How can I determine the solar flux by using hourly DNI value?

I'll be appreciate if you answer my any question..
Thanks for your answers guys..

Cheers
Kagan

Dear Kagan,

In SAM, the solar field thermal capacity is sized to meet the design requirements of the power cycle.

You may want to choose a solar multiple that minimizes the project LCOE. In the power tower models, the optimization process requires two steps: Optimizing the field layout, and optimizing the solar multiple. When the system includes storage, you may also want to optimize the size of the storage system. The sample file "Tower Field Optimization.zsam" illustrates how to use the SamUL scripting language to automate the optimization of field layout, solar multiple and storage capacity.

The heliostat reflective area is the product of the heliostat length and width for rectangular heliostats. For round heliostats, the heliostat width is the diameter, so the area is (Heliostat Width/2)^2 * pi. The field reflective area is the heliostat area times the number of heliostats.

SAM calculates the flux incident on the receiver as an internal calculation, and reports the equivalent total thermal energy on the receiver for each hour in MWh in the hourly results. SAM also writes flux data to a flux map file that you can see by pressing Shift-F9 after running simulations.

Best regards,
Paul.