The higher level of expenditures is driven by a 21% increase in unit generation costs caused primarily by the emissions caps and offset only slightly by a small decrease in electricity demand.
The price increase of unit generations can be further offset. 
mnli hypothesis: The price increase of unit generations can be further offset.  premise: The higher level of expenditures is driven by a 21% increase in unit generation costs caused primarily by the emissions caps and offset only slightly by a small decrease in electricity demand.