Power Engineering

The Air Really Is Getting Cleaner

By Robynn Andracsek, P.E., Burns & McDonnell and Contributing Editor

For those of us down in the trenches on a daily basis, trying to implement specific regulations of the Clean Air Act (CAA), it is instructive to step back and realize that the CAA really is working. When measured objectively, the air actually is getting cleaner. And, if cleaner air is the goal of the CAA, then it is successful.

The first principle of the CAA is defining what is, and what is not, clean air. This is accomplished numerically with the National Ambient Air Quality Standards (NAAQS). Compliance with the NAAQS is determined by monitoring air quality at stations all over the U.S and comparing the measured values to the standards. As seen in Figure 1, monitored concentrations of every pollutant measured (ozone, carbon monoxide, lead, nitrogen dioxide, and sulfur dioxide) have decreased since 1980. Particulate matter has been monitored nationally for a shorter period (since 1990 for PM10 and since 1999 for Pm2.5) but also shows a downward trend. This data was normalized so that all pollutants would fit on the same scale. Carbon dioxide and other greenhouse gases (GHGs) are not shown since there are no NAAQS for GHG and therefore no GHG non-attainment areas.

Cleaner air makes sense when you realize that the total tons of pollution emitted from factories, power plants, and other industrial sources has been cut by almost two-thirds, as shown in Figure 2. In addition, from 1990 to 2005, emissions of air toxics declined by approximately 42 percent. These reductions are the result of implementing stationary and mobile source regulations.

At the same time however, the total number of cities with "bad" air has not shown the same consistent downward trend. This is due to the EPA redefining "unhealthy" air. From 2003-2005, the number of nonattainment areas doubled. This does not mean that air quality became twice as bad. As required, EPA reexamines the NAAQS every five years and this dramatic uptick in the number of nonattainment areas is due to two actions by EPA. First, EPA shortened the ozone NAAQS averaging time from an 8-hour basis to a 1-hour basis. NAAQS with shorter averaging times are harder to meet. Secondly, EPA added particulate matter less than 2.5 microns in diameter (Pm2.5) as a NAAQS pollutant.

EPA recently added 1-hour averaging periods to the NO2 and SO2 NAAQS. When the nonattainment areas are designated for these new NAAQS in 2014-2015, another surge in nonattainment areas can be expected, without a causal increase in pollutant emissions or degradation of air quality.

The NAAQS aren't the only aspects of the CAA that works. The Acid Rain reduction program, emissions inventories, and Title V operating permits have also met their objectives of reducing pollution and better defining a source's emissions and responsibilities. Not so successful are Prevention of Significant Deterioration (PSD), Mercury and Air Toxics Standards (MATS), and Cross-State Air Pollution Rule (CSAPR). These programs have been riddled with errors, fraught with confusion, and haunted by legal delays.

Sometimes it's hard to see the forest for the trees. But the efforts of industry and yes, even coal-fired power plants, to operate in a cleaner manner are improving the nation's air quality.

More Power Engineering Issue Articles
Power Engineerng Issue Archives
View Power Generation Articles on PennEnergy.com

Sponsored by FLSmidth

Related Articles

Using Predictive Analytics to Minimize Risk Associated with Aging Assets

It's no secret that an aging asset infrastructure is of major concern to power generation companies.

Remote Vibration Monitoring Keeps Power Plants Running at Full Capacity

You can get the monitoring and analysis you need without requiring your equipment specialist to be on-site at the plant.

Follow Power Engineering on Twitter

Latest News

02-25 Henry Hub Average Natural Gas Spot Prices

02/25 Henry Hub Average Natural Gas Spot Prices

The Henry Hub is the pricing point for natural gas futures contracts traded on the New York M...
 GDF Suez wants Areva to deliver nuclear reactors, wind turbines

GDF Suez wants Areva to deliver nuclear reactors, wind turbines

GDF Suez says it received guarantees from Areva for planned nuclear reactors in Turkey and wi...
 CB&I: We’re not liable for $247mn nuclear power project penalties

CB&I: We’re not liable for $247mn nuclear power project penalties

Chicago Bridge & Iron (CB&I, NYSE: CBI) say they should not be liable for any of the ...
 Siemens upgrades I&C system of GE steam turbines for first time

Siemens upgrades I&C system of GE steam turbines for first time

Siemens (NYSE: SI) received an order to upgrade the instrumentation & controls (I&C) ...
 Weekly Coal Production

Weekly Coal Production

The Weekly Coal Production Report has been updated for the week ended February 21, 2015.

 North Dakota coal production increases 4 percent in 2014

North Dakota coal production increases 4 percent in 2014

North Dakota is known for its booming oil fields, but coal mining in the state also is a heal...
 Spanish company buying US utility serving northeast for $3B

Spanish company buying US utility serving northeast for $3B

Spain's leading electricity and natural gas utility, Iberdrola, says it will buy the northeas...
 Ohio utility regulators reject AEP plan for coal plants

Ohio utility regulators reject AEP plan for coal plants

Ohio utility regulators have rejected an American Electric Power proposal to guarantee profit...

Power Engineering Current Issue

03/01/2014
Volume 118, Issue 3
1403PE-cover

Products Showcase

Dynamic Fluoride Ion cleaning DFIC of industrial natural gas turbines Hi-Tech Furnace Systems

Dynamic Fluoride Ion Cleaning of IGT Parts

The Dynamic Fluoride Ion Cleaning (DFIC) Process from Hi-Tech Furnace Systems is able to clean deep, narrow cracks of oxides by cycling between negative, atmospheric, and positive pressure.

Archived Articles

2000 | 2001 | 2002 | 2003 | 2004 | 2005 | 2006 | 2007 | 2008 | 2009 | 2010 | 2011 | 2012 | 2013

Buyers Guide Product Listings

Amended Silicates HgX

Amended Silicates® HgX is an innovative, non-ca...

PowerPAC Premium®

This halogenated powdered activated carbon (PAC...

The NEW FastPAC™ Series

These patent-pending, next-generation powdered ...

Circulating Dry Scrubber

CDS removes acid gas pollutants and heavy metal...

Power Industry Wire News

Manitok Energy Inc.'s CEO Mass Geremia Interviewed by The Energy Report

Manitok Energy Inc.'s CEO Mass Geremia Interviewed by The Energy Report

UGE International Ltd. Announces Private Placement

UGE International Ltd. Announces Private Placement

REMINDER: Scorpio Tankers Inc. Announces Fourth Quarter and Year End Earnings Release Date and Conference Call Details

REMINDER: Scorpio Tankers Inc. Announces Fourth Quarter and Year End Earnings Release D...

Mountain High Acquisitions to Acquire Freedom Seed and Feed, the First Federally Permitted Hemp Seed and Fiber Farm in the USA

Mountain High Acquisitions to Acquire Freedom Seed and Feed, the First Federally Permit...

NW Natural Reports 2014 & Q4 Results

NW Natural Reports 2014 & Q4 Results

Power Engineering

Article Archives for Power Engineering Magazine

Continuing Education

Professional Development Hours

To access a course listing associated to a specific topic listed below, click on the topic of choice from the list below.

Latest Energy Jobs

View more Job Listings >>