Unless the Government agreed to incorporating these in its emissions trading scheme the Coalition would not vote for it this Thursday.

Yesterday Turnbull made public the independent research he and Nick Xenophon commissioned in June that claimed the Government's scheme could be made cheaper, greener and smarter. The report was not policy, Turnbull cautioned.

Both acts served the same purpose of buying time. Even if the Government was prepared to make changes along the lines suggested, it could not do so by Thursday. So the Coalition, in a rare act of unity, will vote down the bill on Thursday. The trouble comes after that. The Government will reintroduce it three months later, and if rejected again it becomes a trigger for a double dissolution.

Before then, Turnbull is banking on being able to negotiate amendments and Labor having to deal or risk being seen as obstinate. It is a gamble because there is a hard core of Liberals who oppose doing any deal with the Government, and they have the backing of the Nationals. They will be just as hostile in November.

There is a sentiment that the Liberals should bite the bullet and pass Labor's scheme this week. Some will cross the floor. It will be an ugly few days for Turnbull, but the issue will be off the books. If the scheme proves to be a stinker, voters will blame the Government, not the Opposition.

It is either that or another three months of squabbling.