Basically, familiarity to all units is the main key in all engineering, sample of this are the question you mentionened above. e.g.
Kilo - a number times 1000
mega - a number times 1000000
Going back to your question " Kwh generation of 1 MW Power plant". First things first, you have to know the demand kW or MW of the power plant then multiply this with time usage (in this case you use hour). Simply you will get the result.
For Example,
Your 1MW Power Plant is operating at 100% demand with 8Hrs usage.
Simply mutiply 1000000*8
then you will have a product of 8000000 Wh
to convert it to Kwh you just devide it to 1000
8000 will be the KWhr consumption at 8hr 100% demand of the power plant.
Lastly, what do you mean by evacute in your question?
Thanks Benn, for the reply. What I would like to know that while sizing the Power Plant's Capacity, what PLF (Plant Load Factor) along with the average hours per day operation of the Plant should be considered.
With regards to evacuation, I meant that to transmit this generated power of 1 MW, what should be ideal KVA of the transmission line and how do we decide that?