The way I see it, as is it is destined to fail. I imagine National Grid/RI Energy will attempt to undercut to kill the program if it's going to damage the bottom line.

Looking at my current bill I'm seeing a 0.17785 charge so even paying the highest rate on the current notification will bring down 0.12321 I'll still be saving money as well as contributing as long as I can afford it.

Only been in RI for 7 billing cycles worth, however so I don't got personal historical data for it.
0.0781 x 2
0.14127498 x 1
0.17785 x 4