I live in the Hartford CT area and we have Trash to Energy AND single stream recycling. First - Trash to Energy. The poster above was correct about it not being much of a net energy gain. They burn it in an oil fired plant. Cardboard, food waste, etc. all gets burned. The big thing isn't the energy as much as it is that we don't need a dump anymore except for the ash, which is compact and easy to dispose of. The main garbage dump in Hartford was closed years ago. So overall, a good option to lower the volume of landfilled items and that is the main benefit.
As for single stream, we used to sort it, but now use a large single stream bin. A great improvement all around. Here's why: I toured the recycling center with my daughter's elementary school class. I watched the trucks pull in. This was in the "sort it" days. So a guy would pick up your bin, throw the cardboard with the cardboard, the plastic with the plastic (by type), the glass with the glass, etc. The truck had an opening for each. Anyway, the truck pulls into the recycling center, and the back opens, and the dumper rises, and all of it gets mixed together! I finally asked why, and they didn't have a good answer. So what was the point? It was totally inefficient in that the sorting process the guy did at every house was essentially a useless exercise. And he knew it too, so those sorts were not particularly well done. Bottom line, single stream makes far more sense - sort it at the recycling facility. Don't pay a guy to do it at the curb. Have a truck pick up a big bin automatically.
Finally, the financial end of this... When we went to single stream, we got a garbage can (95gal) and a recycle can (95gal). We found we were producing more garbage than recycling. So I sent my brother in law, who was living with us to go purchase another garbage can. They explained to him that they would like to sell him a recycling can instead. The town made money on the recycling, and garbage cost them. So he came home empty handed. I told him to go down and buy the extra garbage can - I didn't care what it cost the TOWN... I cared about keeping the garbage out of the recycling. So I sent him back and reluctantly they sold him another garbage can.
Roll the clock forward, and the town does what government does best. Since they made money on recycling, they announced that anyone who had more than one garbage can would be issued a new recycle bin and they would be taking the extra garbage can that I had paid for away. And recycling would only pick up every other week. And if I wanted to keep my extra garbage can, I had to pay a $150 a year subscription for it. So, they did what made economic sense for them at my expense.
Of course, my solution to this was simple. I had the same number of cans, it's just one went from Garbage Green to Recycle Blue. So I threw my garbage in the recycle bins. Problem solved for me. And probably part of the reason recycling is more expensive now because of short sighted government workers wishing things were different and turning me into a profit center!