Well I know one part of why the rates increased which is as follows:
The state (Lamont administration) has an aggressive carbon emission goal, and the states only nuclear plant (which is considered clean energy) Millstone which provides power to 50% of the state population was threatening to close as they stated that they were at risk to cease operations because of low market prices. Long story short Lamont offered them a new 10 year contract and required the state utilities to buy half of millstones power output through a power purchase agreement that was rather costly. Also there were tons of questions as to whether Dominion (who owns millstone) was even in financial trouble, they were reluctant to hand over the books and PURA said they were viable through at least 2022
Anyways not sure what else is going on with ES but this certainly is a driver, though it should be no means increase a bill by hundred(a) of dollars lol.