In early June 2014, the U.S. Environmental Protection Agency (U.S. EPA) announced proposed new rules that would cut emissions of carbon dioxide—a primary greenhouse gas (GHG)—from power plants by approximately 30%. The rules are part of the more comprehensive Climate Action Plan the Obama Administration rolled out in mid-2013, which included a series of discrete steps the United States will take to address the growing effects of climate change.
The proposed rules would require each state (except Vermont) to cut carbon dioxide emissions by a set amount predetermined by U.S. EPA based on a series of metrics, including the percentage of existing coal-fired power in the state, current use of renewables, and what is reasonably achievable without too great of a burden. Based on these reductions, U.S. EPA has estimated that when taken together, carbon-dioxide emissions from all power sources in the United States will decline by approximately 30% below 2005 levels by 2030.
It is important to note, however, that carbon dioxide emissions from power plants already have been reduced by approximately 12% from 2005 to 2013, so this rule would result in an additional “real” reduction of 18% on average by 2030 compared to today.
Since the industrial revolution, burning of fossil fuels and clearing of forests has led to increasing concentrations of GHGs in the Earth’s atmosphere. Documentation dating back to the late 1800s—when records started being kept—shows a clear relationship between the amount of carbon dioxide in the atmosphere and global temperature increases.
In addition, ice core samples taken from the Arctic Circle can confirm these changes going back thousands of years. The ice cores show that pre-industrial levels of atmospheric carbon dioxide remained relatively unchanged; it is only after the industrial revolution that a rapid increase in these concentrations occurred.
The presence of GHGs in the atmosphere is a concern because these gases act to absorb and trap solar radiation. Although a certain amount of carbon dioxide and other GHGs is necessary to maintain a relatively warm Earth that can support life, excess amounts are causing temperatures to increase beyond that to which most living organisms have adapted.
Industry and other special interest groups have been fighting U.S. EPA’s ability to regulate carbon dioxide emissions for decades. In fact, the United States has been reluctant to participate in any type of GHG emission cutting, and signed but did not ratify the Kyoto Protocol, an international agreement among industrialized nations to cut GHG emissions.
Fortunately, the Supreme Court eventually ruled in a recent finding that EPA did have the authority to regulate carbon dioxide as an air pollutant under the Clean Air Act. Obama’s Climate Action Plan, and the carbon dioxide rule in particular, is perhaps the most significant steps the federal government has ever taken to curb U.S. GHG emissions.
But although this rule to regulate carbon dioxide emissions is unprecedented in the United States, it may be too little, too late. Although the rule is a good first step, it may do little to slow the already occurring changes in the Earth’s climate.
Power generation is a significant source of carbon dioxide emissions in the United States, accounting for approximately one-third to one-half of all GHGs. In particular, aging, coal-fired power plants are the largest current sources of carbon-dioxide emissions. So by targeting these primary sources, U.S. EPA is focusing on the area most likely to result in a significant positive impact on reducing the effects of climate change.
In addition, the rule is designed to give States a significant amount of autonomy and flexibility on how they will achieve their reduction goals. For instance, states may choose to upgrade existing plants; migrate to more natural-gas powered plants (though many of these too are aging and, hence, produce significant GHG emissions); rely more on renewables; incentivize energy efficiency; or some combination of these.
While not calling other emissions out specifically, the rule also will lead to reductions in other GHGs such as sulfur dioxide, nitrogen oxides, and ozone, which are also typically produced by power plants.
As expected, much of the protest came from states with significant reliance on coal-fired power, industry groups, and others that are concerned with cost implementation. However, U.S. EPA addressed these concerns from the very beginning by illustrating how implementation costs will be far outstripped by the benefits that will be reaped through improvements in health and the environment.
Unfortunately, however, there are many concerns regarding the real, tangible value of this rule. First, as mentioned earlier, the estimated reduction in GHG emissions will likely only be around 18% below 2012 levels because approximately 12% has already been achieved since 2005 as states took measures to reduce emissions in anticipation of an impending rule. In addition, this additional 18% is really only an approximation. With the way the reductions are divided and vary between states, the actual reduction could be significantly less; though there is always the small chance that it could be more as well, though this is unlikely for a variety of reasons.
Assuming, however, that the rule passes as is, with the approximately 18% “real” reduction, the reality is that this will have little effect on climate change currently in progress. For most of the United States, 2012 was hottest year on record to date; several of the years in the last decade have been the hottest ever recorded worldwide. In fact, average temperatures have increased nearly 1 degree C since the industrial revolution began. Carbon dioxide concentrations are nearly 400 ppm compared with approximately 300 ppm for the entire period up until the industrial revolution.
Another problem with the rule is that it does not address transportation emissions at all, which is about equal to energy production in the amount of GHGs produced. Perhaps the biggest problem, however, with attempting to reduce carbon dioxide is the already existing excess levels of GHGs present in the atmosphere. Carbon dioxide and other GHGs can remain in the atmosphere for years if not decades (some even for millennium). In addition, rates of emissions greatly exceed rates of removal, through natural cycles such as absorption in sinks, breakdown, etc. As a result, some percentage of existing GHGs will remain in the atmosphere for thousands of years even if current emissions were cut to zero immediately. These gases will continue to negatively affect the Earth’s climate as long as they are present.
As a result, even with this pending reduction, atmospheric concentrations of GHGs will continue to increase. On the other hand, without any cuts, concentrations of GHGs will increase far more rapidly. The only scenario that might work is an immediate 50 to 100% cut from present day levels, and even then, it would be many years to several decades for temperature increases to stabilize. These moderate reductions as indicated in the proposed rule will have little tangible effects. Even complete removal of carbon dioxide emissions would only lead to a modest decrease in atmospheric concentrations in the coming decades.
Finally, the United States is only one of many countries in the world. Although the United States is a significant producer, contributing about 20% of total GHGs and carbon dioxide, there are many other countries that also would need to reduce emissions to have a measurable impact. Most problematic is that many developing nations—in particular, China and India with over 30% of the world’s population combined—are catching up with their GHG emissions.
Previously, many countries agreed on a somewhat arbitrary benchmark of keeping global temperature increase to less than 2 degrees C; unfortunately, based on current projections, it is not unlikely that an increase of almost 4 degrees C may occur by end of this century. Unfortunately, scientists do not really know what temperature increase the world can really absorb without significant environmental, economic, and health impacts. For example, California is already in a period of historic drought, a state that grows nearly 50% of U.S. fruits, nuts, and vegetables.
The proposed power plant rules are, however, a start.