Whatever he's posting is pretty misleading considering Massachusetts imports far more energy from the regional grid than it produces (and the regional grid is basically entirely natural gas and nuclear).
You can read more here: https://www.eia.gov/states/MA/overview
From my understanding, this seems largely like a sleight of hand: shut down nuclear & fossil fuel plants, replace a fraction of that capacity with renewable - but you can call yourself green because it's a larger share --- and then import the lion's share of your electric from a non-green heavy grid.
You can see MA's all source generation here (decreasing from 10 / 20 years ago): EIA.gov website. I know MA has installed a ton of residential and small scale solar, which is fine to celebrate but I see the data being used very loosely. In fairness, I think that chart is not including the 4,000 MWh of non utility solar, so a little overstating the reduction.