Question

Estimate the generating cost per unit supplied from a power plant having data:
Output per year = 4 × 108 kWh, Load factor = 50%, Annual fixed charges = Rs. 40 per kW,
Annual running charges = 4 paisa per kWh

Answer 1

Given :

There are 4 generating units in the plants having 108 kW capacity.

Therefore, total capacity of the plant = 4 * 108 kW = 432 kW

Load factor for the plant = 50 % = 0.5

Since, load factor = Average power / Peak power

Therefore, average power supplied by the plant = Load factor * total capacity of the plant = 0.5 * 432 kW = 216 kW

Therefore, energy supplied by the plant in kWh = average power supplied by the plant * Number of hours in an year

Since, Number of hours in an year = 365*24+6 = 8766

Therefore, energy supplied by the plant in kWh = 216 * 8766 = 1893456 kWh

Now, since annual fixed charges = Rs. 40 per kW

Therefore, total annual fixed charges = Rs. 40 * total capacity of the plant in kW = Rs. 40 * 432 = Rs. 17280

Therefore, annual fixed charges per kWh = annual fixed charges / energy supplied by the plant in kWh

= 17280 / 1893456 (Rs. / kWh) = 0.00912616929 (Rs. / kWh) = 0.912616929 (paisa/ kWh) (1 Rs. = 100 paisa)

= 0.912616929 paisa per kWh   

Since, Annual running charges per kWh = 4 paisa per kWh

and generating cost per kWh = Annual fixed charges per kWh + Annual running charges per kWh

= 0.912616929 paisa per kWh + 4 paisa per kWh = 4.912616929 paisa per kWh

Since, 1 unit = 1 kWh

Therefore, generating cost per unit = 4.912616929 paisa ==> ANSWER

Hope the answer helps :)