Question 9.11: Using utility structure B of Table 9.8, calculate the utilit......
Using utility structure B of Table 9.8, calculate the utility bill for a commercial facility during a winter month when the energy use is 70,000 \ kWh, the billing demand is 400 \ kW, and the average reactive demand is 150 \ kVAR.
Accounting for all the charges considered by utility rate B (see Table 9.8), the electric energy bill for the winter month can be calculated as follows:
(a) Customer charge=\$0.00
(b) Energy charge=400 \ kW*\$0.059/kWh+30,000 \ kWh*\$0.042/kWh=\$3,620.00
(c) Demand change = 50 \ kW*\$12.39/kW+350 \ kW*\$11.29/kW=\$4571.00
(d) Fuel cost adjustment=70.00 \ kWh*\$0.01605=\$1,123.50
(e) Reactive demand change= 150 \ kVAR*\$0.20/kVAR=\$30.00
(d) Taxes= \$0.00
Total monthly charges =(a)+(b)+(c)+(e)+(f)=\$9344.50
The average cost of electricity for the month is then \$9,344.50/70,000 \ kWh or \$.1335/kWh.
TABLE 9.8
An Electric Utility Rate with Demand Charges for Commercial General
Service (Utility Rate B)
| Summer (Jun–Sep) | Winter (Oct–May) | Billing Item |
| 0.00 | 0.00 | Customer charge ($) |
| 25ز0 | 25.00 | Minimum charge ($) |
| 0.01377 | 0.02 | Fuel cost adjustment |
| 0.00 | 0.00 | Tax rate (%) |
| 3 | 3 | No. of energy blocks |
| 40,000 | 40,000 | Block 1 energy size (kWh) |
| 60,000 | 60,000 | Block 2 energy size (kWh) |
| >100,000 | >100,000 | Block 3 energy size (kWh) |
| 0.065 | 0.059 | Block 1 energy charge ($/kWh) |
| 0.047 | 0.042 | Block 2 energy charge ($/kWh) |
| 0.042 | 0.039 | Block 3 energy charge ($/kWh) |
| 2 | 2 | No. of demand blocks |
| 50 | 50 | Block 1 demand size (kWh) |
| >50 | >50 | Block 2 demand size (kWh) |
| 13.71 | 12.39 | Block 1 demand charge ($/kWh) |
| 12.52 | 11.29 | Block 2 demand charge ($/kWh) |
| 0.20 | 0.20 | Reactive demand charge ($/kVAR) |