New to smart meter - confused!

Have a smart meter since last November, but only activated it last month. Ive been recording its readings every few days as im trying to figure out how it knows i have a night boost with EI for 2 hours.. to me, it seems it doesnt.. so not sure how EI know what i consume in these 2 hours..

Anyway, i also created an acc with ESN Networks and today im checking the downloadable HDF file...Filtered by March & reading type. then sum the import reading column (assume this is Kwh?).. to my dismay for march it sums to ~700.. but when i check the readings i took manually over the month, ive only used 387...

No that i look again, the numbers on the file are in KW every 30 mins.. so how do i figure out kWh's?