The Supreme Court and Carbon Emissions

The Supreme Court ruled today that the EPA cannot rewrite law (in this case The Clean Air Act) to accommodate new information without Congressional approval. In this instance, EPA added carbon dioxide to its list of pollutants and most lawsuits raised to challenge this were dismissed. But one made it through and The Supreme Court took it up. This is a good explanation of the issue:

The CAA’s [Clean Air Act] Prevention of Significant Deterioration (“PSD”) permitting program was designed to prevent the significant deterioration of air quality in areas that were already complying with the national ambient air quality standards for at least one criteria pollutant. Taking up its charge following the Court's ruling in Mass. v. EPA, EPA introduced new regulations covering greenhouse gas emissions from motor vehicles.  EPA then extended the PSD permitting program to cover large stationary sources of greenhouse gas, as required by the plain text of the CAA and a three-decades-old interpretation of the Act followed by both Democratic and Republican Presidents alike.

This takes the issue from the other side.

When the EPA added carbon dioxide to the pollutants it regulates, the agency also decided to raise the established limits [from 250 tons per year to 100,000 tons per year] without congressional approval. That's because carbon dioxide is so plentiful that a literal interpretation of the Clean Air Act could have extended the new rules to thousands of houses, office buildings and shopping malls.

Naturally,industry was less than pleased with this and brought suit (through The Utility Air Regulatory Group). Today, the court agreed with them, at least in part, but as Justice Antonin Scalia pointed out, “EPA is getting almost everything it wanted in this case.”

Today the Supreme Court decided that the EPA is not obligated to regulate GHGs under the PSD and Title V programs and that the EPA is not permitted to rewrite the applicable statutory emission thresholds.  … [T]he Court also concluded that it was reasonable for the EPA to interpret the Act to allow for the regulation of GHG emissions from sources already subject to regulation under the PSD and Title V program.  What this means is that large stationary sources (think big power plants and industrial boilers) that are already regulated as major stationary sources under these programs will have to control GHG emissions when they control other emissions.  But sources that only emit large amounts of GHGs will not become subject to EPA’s regulatory authority under these provisions.

I wasn’t sure when I read this what it meant to the proposed carbon emission rules. As it turns out, very little:

But the ruling was confined to only one regulatory provision, and it is not likely to directly affect the broader climate-change policy that the administration announced earlier this month. That policy relies on a different part of the law that says states must take steps to reduce harmful air pollutants, which include greenhouse gases.

So EPA overstepped its authority in this instance (“not permitted to rewrite”), but it can still regulate carbon emissions under the Clean Air Act – which the Supreme Court had already affirmed in 2007. 
Though this has no nuclear pickup – maybe for some manufacturing outlets, but not much – there is still a seed of interest rooted in the courts as the third branch of government. With the new carbon rules, we may see suits brought against the EPA questioning its authority on issues both broad and narrow. Petitioners may win some and lose some, but the interested can have a say.
The new carbon emission rules have the capacity to truly value nuclear energy for its role in mitigating climate change. Various legal challenges to the rules, even if they occur, seem unlikely to mitigate that value, but I thought this current case was a good reminder that such rules are not graven in stone nor are they endlessly malleable. It’s early days for the new rules, of course, and likely to become increasingly interesting in the next couple of years as the review period ends and the rules are promulgated.
---
Speaking of the value of nuclear energy, the Department of Energy has released a paper called Electricity Generating Portfolios with SMRs, that is, small modular reactors. This is from the abstract:

This paper shows that SMRs can competitively replace coal units in a portfolio of coal and natural gas generating stations to reduce the levelized cost risk associated with the volatility of natural gas prices and unknown carbon costs.

Understanding the paper requires special knowledge, but it does explain itself effectively as it rolls along. Worth reading (well, the abstract definitely, the rest is up to you).