I'm finding it hard to understand the notion that this produces "more" ENERGY than it requires. My guess is that this notion comes about from not factoring in all the energy inputs required to run the process and to produce the additives......Can someone respond to this??? Most processes I am familiar with, if not all, seem to balance out along the way, as much as we would love to have a better energy deal.....

Cool. Like having an undo button on a thing made from crude oil.
Which gets me to the stupid side of our usage of crude oil: Burning it for one-time purposes such as transportation. Once done, it's gone. No undo button.
What a difference.

I predict soon there will be a "Gold Rush" of harvesting vessels that will compete with each other to turn the huge "Vortex of Waste" now floating in the Northern Pacific Ocean into much needed raw materials in the most efficient way.
Good news for the Planets ecology!

In response to Carol Zedeck:
I do not know for certain, but here are my assumptions. They are calculated "energy used" as the input energy required to put the bag through pyrolysis, and the "energy output" as the usable energy derived through combustion of the resultant fuel.
In this way, it is not violating the 2nd law of thermodynamics, because there is significant chemical energy stored in the bag which is converted into a more useful form through the research team's process.
This is not dissimilar to the act of extracting and refining oil; if it took us more energy to extract and refine the oil than we actually got out of using the oil, it would be pointless to even go through the process :)
Hope that cleared it up a bit?

I am excited at all the calories that will be burned by people climbing trees to get the bags. O also walking waterways collecting all the bags caught there. As the Beatles sang, "Let It Be"

More reason & save & now reuse for Fuel vs waste, awesome theres our fuel America, no more from OPEC, all from plastic bags, & in CA we ban plastic bags, maybe reuse for Fuel then OK Governor Brown.

Shopping bags made from LDPE & HDPE are 100% recyclable so why not just turn them back into bags which is less effort and energy than turning them into petroleum products

@CaptD
I predict (and have done for ages) that, one day, we will start mining landfill sites for all those precious things that were once just rubbish.

@ BMFan
This process won't be ruined by a bit of the wrong plastic being put in the mix thereby saving huge amounts of energy from not having to sort the mix.

This was done before
A japanese scientist did Blest Machine
https://www.youtube.com/watch?v=KBUGAUGqaY4
A man from ethiopia made it
https://www.youtube.com/watch?v=1Qi54pTAXZ4