1) Most of our electric generation is fired by natural gas, not coal or oil.
2) Our public transit infrastructure uses low sulfur diesel fuel.
2a) Since it makes no sense for oil companies to deliver low sulfur fuel to just public transit it’s likely that the stations that sell diesel are also using low sulfur fuel.
3) We have had and probably still do good representation for environmental law in the state. So that likely had an impact.
Now if we could only do something about the gasoline powered vehicles. I keep saying, if you can get the range of electric vehicles up to 200 miles, quick re-charge on the order of 10 to 15 minutes and a price under $20K you could replace EVERY SINGLE gasoline powered passenger car within 5 to 7 years. And even though the cars allegedly only contribute 38% of the greenhouse gases it’s still a significant reduction in carbon dioxide, benzene etc. if we went pure electric.