Final answer:
The maximum demand for the month is 1028 kW, and by reducing the demand by 15%, the new account total for the next month would be R 66582.25, with the same energy consumption.
Step-by-step explanation:
To calculate the electricity cost for an industrial concern using 325000 units of electricity, converting units to kWh is necessary as electricity prices are often quoted in cents per kilowatt-hour (c/kW.h). Since 1 unit of electricity is equal to 1 kilowatt-hour (kWh), the concern used 325000 kWh of electricity. To find the maximum demand, we use the demand charge formula: Total account = (Energy charge) + (Demand charge), where Energy charge = energy consumed × cost per unit, and Demand charge = maximum demand × demand cost per kW.
Given:
Total account (R) = R 73000,
Energy consumed (kWh) = 325000,
Cost per unit (c/kW.h) = 9.4,
Demand cost per kW (R/kW) = R 41.25.
First, calculate the energy charge by multiplying the cost per unit with the energy consumed, which is (325000 kWh) × (9.4 c/kWh) = R 3055000 c = R 30550. Then, to find the demand charge, subtract the energy charge from the total account: R 73000 - R 30550 = R 42450. Finally, divide the demand charge by the demand cost per kW to get: R 42450 / R 41.25 per kW = 1028 kW.
To find the new account for the next month with a 15% reduction in maximum demand, multiply the maximum demand by 85% (100% - 15%), which is (1028 kW) × (85%) = 873.8 kW. The new demand charge is (873.8 kW) × (R 41.25 per kW) = R 36032.25, and the energy charge remains the same at R 30550. Therefore, the new account total is R 36032.25 + R 30550 = R 66582.25.