Field freeze protection

Hi!

I am modeling a parabolic trough plant using the physical model. Solar Salt is used as HTF and therefore the system experiences high parasitic losses at night due to freeze protection. Being freeze protection modeled with electric heat trace, where does this electricity come from? The system has only 6 hours of storage (is not producing during the whole night) and no fossil backup.
Is electricity bought from the grid? If this is so, at what price?

Thanks,
Sincerely

Irene

Dear Irene,

SAM assumes that the electricity for freeze protection comes from the grid. SAM simply reduces the system output in each time step by the freeze protection energy required in that time step, so the electricity price is whatever the PPA price that applies in that time step is. If your project does not involved time-of-delivery (TOD) factors, then the price is equivalent to the PPA price reported on the Summary tab on the Results page.

Best regards,
Paul.