You are welcome.
Actually, I do not know figures of Pakistan, but here are some details (and numbers) what I know about Karachi that I believe is quite accurate:
Supply and demand: KESC (2007):
KESC own electricity generation capacity ~ 1540 MW
Further, KESC buys from:
IPP ~ 250 MW
KANUPP ~ 40 MW
Pak Steel Mills ~ 20 MW
Total Supplies (approximately) ~ 1850 MW
Demand at peak hours in Karachi is ~ 2500 MW**.**
So, demand at peak hours requires around 650 MW more electricity. KESC tries to cover this gap by buying electricity from WAPDA (if WAPDA can sell). If WAPDA do sell than there would be no load shedding other then due to technical problems. Unfortunately, WAPDA do promise but do not necessarily manage to sell electricity at peak hours, hence regular load shedding due to shortage of electricity.
Future: What I know, KESC after privatization has already started building two electricity generating plants, one should get completed in 2008. They are:
1: Korangi Thermal power plant (should have got completed in 2008) has generation capacity of 220 MW
2: Bin Qasim thermal power plant (would complete later) has electricity generation capacity of 575 MW.
If these two plants do get completed then there would be no dependence for electricity on WAPDA. Though, as electricity demand is increasing day by day, KESC has to start building more power plants (that I do not know if they have).
I do not think that there is any problem for Pakistan meeting off-peak demands. If there is no supply of electricity during off-peak hours, then that is due to mismanagement, incompetency, technical problems, or Transmission and distribution problems.