Please dont go for UPS,that would not run for more than 1-2 hours.Generators are best,use them as long as you want,a 1200watts generator could run for almost 4-6 hours continous,the fuel consumption will be 4 hours per liter. According to you that load shedding is now for 1 after 1 hour,the UPS wont charge in 1 hour,it needs almost 3-4 hours continous to get completely charged.
So at the end,ill again say,buy Generator,1200watts generator is for 8-10k in sialkot.