An energy auditor was only provided with the prior two years of electric utility data for a facility. After studying the data, the energy auditor identified that the peak demand charges were the most significant portion of the utility bill. The monthly actual peak demand (in kW) and the rate structure for the facility are shown in Tables 1 and 2.

1. Calculate the total and monthly billed demand charges for year 2020..

For this problem, the ratchet clause should be applied using 65% of the maximum actual demand corrected for power factor during the prior 11 months, and pf_base = 0.85 and pf_actual = 0.75.

  

Table 1: The monthly actual peak demand (kW). Year Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 2019 455 505 610 675 755 920 1100 1200 895 650 605 550 2020 495 550 580 600 610 900 1150 1000 900 600 500 515 2021 ? ? ? ? ? ? ? ?