The second shoe has dropped in EPA’s wondering about how to regulate CO2 emissions from power plants. As the shoe dropping metaphor suggests, EPA can now go to sleep for awhile. Everyone else is going to be very busy commenting on this complex issue.

The first shoe dropped in October when EPA proposed repeal of the Obama Clean Power Plan. The Agency correctly cited the well known legal arguments against the CPP, especially that it illegally required States to regulate their entire electric power systems, not just their power plants.

This meant changing (that is, restricting) people’s use of electricity, a favorite green goal. Not mentioned, but certainly there as well, is that the CPP killed off coal fired power. That EPA will follow through with this repeal is pretty certain.

Now comes the hard part, which is figuring out how to realistically regulate power plant CO2 emissions. Or maybe not, which is a big part of the uncertainty. Regulation is only required because of the Obama EPA’s false finding that CO2 emissions endanger public health and welfare. Reversing this Endangerment Finding should eliminate the entire issue of regulation.

EPA well might reverse the Endangerment Finding, but in the interim it is required to move ahead on the regulatory front. So now it is doing just that, but as slowly and carefully as possible.

Specifically it has issued what is officially known as an Advanced Notice of Proposed Rulemaking or simply an ANPRM. Despite the title, this is not a proposed rule. It is just a request for ideas. Imagine that!

The question that EPA is asking is “How can we realistically regulate CO2 emissions from power plants?” and it is a very hard question.

Unlike actual pollutants, which are incidental trace materials, CO2 is a natural product of the combustion process that the power plant is specifically built to execute. This means that CO2 emissions naturally occur in huge quantities. Even worse, these huge amounts of CO2 are embedded in the far greater amounts of nitrogen gas that make up most of the ocean of air that we live at the bottom of.

Thus the correct answer to EPA’s question is simply that it can’t be done, not realistically anyway. That it shouldn’t be done, because CO2 is actually beneficial, adds weight to this conclusion.

But EPA is presently trapped in a Green never-never land, where that obvious answer is not allowed. So the Agency is looking for ideas, which is a legally sanctioned step in the official rule making process.

Nor is EPA simply stalling for time. Then can, at the end of this ANPRM process, come out with a relatively harmless rule, saying that this is all that can realistically be done.

For example, CO2 emissions can be minimized by making the power plant burn its fuel as efficiently as possible. This might even be a realistic requirement, especially for new generating facilities.

There are also some well known wacky ideas out there. Such as burning coal in hugely expensive pure oxygen, rather than air, to avoid the nitrogen problem. Or removing the carbon from the fuel and just burning the hydrogen, even though in coal the carbon is most of the fuel. Or capturing the billions of tons of CO2 in the annual emission stream and sticking it into the ground somewhere. Obama’s EPA liked this one. All of them are absurdly expensive coal killers.

What this means is that the public comments are actually very important. There may be a lot of good ideas out there. In particular, let’s hear from the engineers, not the lawyers or the green economists.

Of course the real answer is to reverse the false Endangerment Finding and stop trying to regulate CO2. Full stop.